Difference between revisions of "INTRODUCTION"

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INTRODUCTION

DINOFLAJ3 is the successor to DINOFLAJ2 (Fensome et al. 2008) and, like DINOFLAJ2, is based in large part on the latest of a series of publications known as "The Lentin and Williams Index" (hereafter "the Index"). DINOFLAJ2 was founded in large part on the 2004 edition of the Index (Fensome and Williams, 2004). This third version of DINOFLAJ is being released in tandem with a new version of the Lentin and Williams Index (Williams et al., 2017). DINOFLAJ2 also incorporated suprageneric classification information from Fensome et al. (1993b). DINOFLAJ3 also incorporates this information, but it has not been updated or modified for this new version. The merit of having both a web version of DINOFLAJ3 and a digital formal publication (the Index) is that the former (as well as providing additional information) offers a modern, flexible, easily accessible database, while the latter enables formal nomenclatural changes to be proposed (see the sections dealing with nomenclature below) and a more conventional presentation for users who prefer that style.

As with previous editions of the Index and versions of DINOFLAJ, the main objective of DINOFLAJ3 is to list all dinoflagellate genera, species and infraspecific taxa based on fossil or fossilizable types included in the literature (in both the 2017 Index and DINOFLAJ3 available to the authors by 31 July 2016), with an assessment of their nomenclatural and taxonomic status. Where life-cycle relationships are known for younger fossils, we indicate the name of the motile equivalent of the cyst name.

The various versions of the Index have three sections: Main Index, Appendix A and Appendix B. These are maintained in conventional fashion in the Index edition that parallels DINOFLAJ3, and can be accessed as such in the left side-panel of DINOFLAJ3. This part of the panel also allows access to subsets of calcareous and siliceous dinoflagellates, which are part of the Main Index. Items in the Appendices are also indicated as such in the list of genera and taxa at other ranks in the upper part of the left side-panel.

The Main Index contains the vast majority of entries, including all taxa in genera based on fossil or fossilizable types. Thus, the majority of taxa in the Main Index represent fossil cysts with dinosporin (organic), calcareous or siliceous walls. However, also included are genera based on mineralized skeletal elements (e.g. Actiniscus); and genera based on extant fossilizable cysts (e.g. Brigantedinium). For convenience, from now on when we refer to "fossils", we imply inclusion of such forms. Also now included among fossils is Succiniperidinium inopinatum, a species based on a motile form preserved in Cretaceous amber.

The line between fossil and living dinoflagellates is becoming increasingly blurred with the growing number of studies of cyst-forming modern species, promoted in large part by the paleoecological significance of these forms. Most researchers agree that a dual nomenclature of fossil and living dinoflagellates (effectively cysts and motile stages) needs to be maintained, even though many prefer to use just one or the other. Dual nomenclature is facilitated by the International Code of Nomenclature for Algae, Fungi and Plants (I.C.N.; see below and Head et al., 2016), but problems arise when a cyst name is based on a living type, which is not covered under the I.C.N.'s "special rules" for fossils. This also causes a quandary in terms of what to include in the main database of DINOFLAJ3, as we consider living dinoflagellates to be beyond our scope and mandate other than to identify equivalence with fossil taxa. For clarity, we include all genera typified by fossils, as well as genera based on preservable living cysts in the Main Index. We would not include modern cyst-based species assigned to extant, motile-based genera unless they are subsequently transferred to a fossilizable-cyst-based or fossil genus.

Appendices A and B contain, respectively, non-dinoflagellate genera (fossil and modern) and dinoflagellate genera that are not based on fossilizable forms. Taxa included in the appendices are those necessary to complete the histories of taxa in the main section, as well as forms that have at one time or other been considered to be, or have been associated with, fossil dinoflagellates. In Appendix B we list all extant dinoflagellate genera and species described from the motile stage and to which cyst taxa have been assigned: in early editions of the Index, such taxa were listed in the Main Index.

In DINOFLAJ3 (in parallel with the 2017 edition of the Index), unless there is a compelling reason not to do so, we have generally accepted the latest systematic treatment of a particular taxon in the literature, provided that the latest author indicates that previous taxononomic treatments and nomenclatural proposals have been considered and are in accord with the rules of the I.C.N.

The number of genera and species in the Main Index has increased remarkably since the first edition of the Index (Lentin and Williams, 1973). The 2017 Index (and DINOFLAJ3) now has 667 generic and 4,464 specific "correct" names, and includes in total 9,910 taxonomic entries in its main part (exclusive of appendices), as well as over 2,400 references. In this edition, 728 taxonomic entries are entirely new, and 1,468 entries have been modified.

A major effort in this edition has been the re-evaluation of 21 references by C. G. Ehrenberg, dating from the 1800s. Many of his papers were initially presented orally, then printed and distributed as separates, then published in journals, these events commonly taking place in different years. Given the convoluted nature of establishing actual effective publication dates, the years assigned to some of Ehrenberg's references have varied from publication to publication (by us and others). Thanks to access to digital reproductions of Ehrenberg's original papers and our re-assessment of information they record, we hope that many of the problems surrounding Ehrenberg's papers have been resolved herein. However, users should be aware that the dates we now assign to many of Ehrenberg's publications have changed from those given in previous editions of the Index and in DINOFLAJ2.

Important note regarding ages

The age cited for each taxon of species or infraspecific rank is, unless otherwise specified, that attributed to it in the protologue. The age cited in the Index is not intended to be a full or up-to-date statement of the range of the species; users are advised to consult the literature for potentially more detailed and precise information.

DINOFLAGELLATES

Dinoflagellates are primarily single-celled, eukaryotic organisms (protists) with at least one life-cycle stage bearing two distinctive flagella: a ribbon-like, wavy transverse flagellum that almost encircles the cell and a longitudinal flagellum that trails posteriorly. The combined motion of the two flagella causes the cell to move forward in a spirally rotating manner. The term "dinoflagellate", originated from the Greek "dinos" (= a whirl or eddy) and the Latin "flagellum" (= a small whip). Most dinoflagellates at some stage in their life cycle have a dinokaryon, a nucleus characterized by the absence of histones and by chromosomes that remain condensed between cell divisions. Mitosis is said to be closed, meaning that the nuclear membrane does not break down and the mitotic spindle remains outside the nucleus. The presence of characteristic dinoflagellate flagella and/or a dinokaryon are diagnostic for the division (or phylum) Dinoflagellata.

Dinoflagellates typically possess vesicles in the motile cell's peripheral region. The latter is termed the amphiesma and the vesicles are, accordingly, termed amphiesmal vesicles. These vesicles may be empty, or they may contain thin to thick, usually cellulosic, thecal plates, the overall assembly of thecal plates being termed the theca. The number and arrangement of the thecal plates is referred to as tabulation. Tabulation is an important criterion in the classification of several major groups, including the Peridiniphycidae, which includes the vast majority of fossil dinoflagellates. Other genera recognized as fossils are included in the Gymnodiniphycidae and Dinophysiphycidae (Fensome et al., 1993b).

Many dinoflagellates are known to have complex life cycles, which usually include one or more, non-motile or cyst stages. The main types of cyst are resting cysts, temporary cysts and vegetative cysts. Most fossil dinoflagellates are thought to be hypnozygotes, resting cysts resulting from sexual fusion (Dale, 1983), although this is unproven except for a few Holocene examples. That they are representative of a cyst stage is confirmed by their possession of an excystment opening, termed an "archeopyle". Several fossil dinoflagellate genera, however, appear to represent other stages in the life cycle. For example, Dinogymnium and its allies appear to represent the remains of discarded pellicles (Fensome et al., 1993b). The pellicle is a continuous layer that in some dinoflagellates occurs beneath the theca or amphiesmal vesicles of motile cells; it may be homologous with the cyst wall.

Dinoflagellates include both autotrophs and heterotrophs, and thus the group as a whole is properly referred to as protists rather than algae or protozoa. These organisms have been treated under both the International Code of Zoological Nomenclature (ICZN) and the International Code of Botanical Nomenclature (I.C.B.N.; now the I.C.N.). To bring a degree of stability to the nomenclature, Downie et al. (1961) proposed that all dinoflagellates be treated under the I.C.B.N. This proposal has been adopted widely (completely for fossils) and in this, as in previous editions of the Index, we follow the rules of "botanical" nomenclature as now found in the I.C.N. The latest version of the I.C.N. is the "Melbourne Code" (McNeill et al., 2012; http://www.iapt-taxon.org/nomen/main.php), and it is this version that we refer to unless otherwise stated. The rules expressed in the I.C.B.N./I.C.N. do change: for example the requirement for an English or Latin diagnosis or description for fossils was instituted in 1995; however, these are not usually retroactive, as that would cause great nomenclatural instability. In the following section we review the I.C.N., especially as it relates to fossil dinoflagellates. But we can't over-emphasize that this review should not be used in place of direct reference to the I.C.N.; note that we have generally omitted reference to measures and complications that we consider not relevant to the nomenclature of fossil dinoflagellates.

RULES OF NOMENCLATURE

General Remarks

The I.C.N. (also referred to herein as "the Code") assumes a hierarchical classification, the basic unit being the species. However, other than this basic exception, the Code is concerned with nomenclature, not taxonomy (Fensome and Skog, 1997). Provisions of the I.C.N. can be suspended through a formal process of conservation or rejection of names; names so affected are listed in an appendix to the Code. Below we highlight key sections of the Code, with examples mainly from this edition of the Index to illustrate the discussion. The Code is divided into chapters and these are divided into sections and articles. Here, for expediency, we focus on articles, which are numbered from 1 to 62 cumulatively across sections and chapters. Related topics are dealt with in paragraphs within an Article, which are generally referred to with numbers subordinate to the appropriate article number: thus the first paragraph in Article 1 is Article 1.1. Most terms are explained at first mention, but further elucidation for many terms can be found in the Glossary below. At the end of the section on Rules of Nomenclature we have compiled a list of key dates at which particular rules took effect.

Ranks of Taxa

Articles 1 to 5 of the I.C.N. are concerned with the ranks of taxa. Article 1.2 clarifies that a fossil-taxon is one based on a fossil type: it specifies that "A fossil-taxon comprises the remains of one or more parts of the parent organism, one or more of their life history stages, in one or more preservational states ...." Thus fossil dinoflagellate cysts clearly fall into the "life history stage category", and as such are well entrenched in the Code. The concept of fossil-taxa replaces earlier concepts of form-, organ- and morphotaxa. Articles 3.1, 4.1 and 4.2 list the ranks to which an organism can be assigned. The ranks referred to in the Index are, in descending scale: genus, subgenus, section, species, subspecies, variety and form

In the first edition of the Index, Lentin and Williams (1973, p.3–5) discussed the infraspecific classification then used for fossil dinoflagellates, and recommended that the ranks subspecies, variety and form not be used indiscriminately, which was a tendency at the time. Consequently, Lentin and Williams (1973, 1975, 1977b, 1981, 1985, 1989, 1993) consistently raised varieties and forms to subspecific rank. An example is Amphorosphaeridium fenestratum var. dividum Davey, 1969c, which Lentin and Williams (1973) raised to the subspecific rank. In the 1998 and 2004 editions (Williams et al., 1998 and Fensome and Williams, 2004), the latest taxonomic treatments in the literature were generally followed with regard to infraspecific rank. However, we still have misgivings about the value of uneven treatment and recommend that, if infraspecific taxa must be used, they be designated as subspecies, nuanced definitions of infraspecific ranks in our view being meaningless in our field. Although we list infrageneric taxa (subgenus and section) after the genus and all of its species, we similarly consider that use of these ranks adds unnecessary complication in the classification of fossil dinoflagellates.

Status, Typification and Priority

Articles 6 to 15 deal with general provisions for the status, typification and priority of names. Article 6 states that a name must be effectively published and validly published in order to be a legitimate name — i.e. one that satisfies the rules. It does not follow that names not in accordance with the rules are illegitimate, as discussed below (as are the definitions of effectively and validly published). Article 6.6 states that "At the rank of family or below, the correct name of a taxon with a particular circumscription, position, and rank is the legitimate name which must be adopted for it under the rules ...." This implies that the correct name is the senior (earliest) legitimate name of a group of legitimate names that are considered to be taxonomic synonyms. The species name Xanthidium (now Spiniferites) ramosum is legitimate, as are the names Xanthidium furcatum, Galea koryka, Hystrichosphaeridium echinoides, Areoligera birama, Geodia? tripunctata and Homotryblium distinctum. All seven names, as well as being legitimate, are correct as long as they are considered to represent separate species. However, the last six species have been considered taxonomic junior synonyms of Xanthidium (now Spiniferites) ramosum. Since we accept all these names to be synonyms, the correct name for the species is Spiniferites ramosus, as this name, being the earliest (or earliest-selected in cases where names are of the same vintage), has priority over the other six names. Note that the word "correct" thus has a specific meaning in this context. Article 6 also has paragraphs dealing with autonyms, new combinations and new (replacement) names.

Typification is the subject of Articles 7 to 10. According to Article 7.1, all names of taxa at the rank of family or below (and of names above family when based on a generic name) must have a nomenclatural type. A nomenclatural type, as defined in Article 7.2, is "... that element to which the name of a taxon is permanently attached, whether as a correct name or as a synonym" (see also the discussion under Article 10.1 below).

Article 7.4 states that: "A replacement name ... is typified by the type of the replaced synonym ...." Thus, Hystrichokolpoma wilsonii, proposed as a substitute name, has the same type as the illegitimate homonym, Hystrichokolpoma truncatum Wilson, which it replaced. Article 7.6 stipulates that the type of an autonym is the same specimen as the type of the (specific) name from which it is derived. Thus, the autonym Circulodinium distinctum subsp. distinctum has the same holotype as Circulodinium distinctum. Interspersed among its Articles, the I.C.N. has Recommendations that ought to be followed but are not binding. Recommendation 7A urges that material on which the name of a taxon is based, especially the holotype, be deposited in a public herbarium or other public collection with a policy of giving bona fide researchers access to deposited material, and that it be scrupulously conserved. Fortunately, this seems to happen more often than not for fossil dinoflagellates, with a very positive impact on the taxonomic stability of the group.

Holotypes, lectotypes, and neotypes of species and infraspecific taxa (e.g. subspecies) are defined in Articles 8 and 9. Articles 8.1 stipulates that the type is a single specimen or illustration, and Article 8.5 restricts this to only specimens (except for epitypes — see below) for fossils. Article 9.1 defines a holotype of a name as the specimen designated by an author as the nomenclatural type. As long as a holotype exists, it fixes the application of a name. When the holotype is missing or destroyed, or when the original author did not designate a holotype (prior to 1958), a lectotype can be designated from the original material (Articles 9.2). Note that the Code specifically uses the word "missing", so there is no need to demonstrate that a holotype has been destroyed in order for a lectotype to be designated. An example of a lectotype is that designated by Jan du Chêne and Londeix (1988) for Achomosphaera andalousiensis, this designation being necessary because the holotype is lost. Under Article 9.3, "original material" can include any specimens seen by the original author, whether or not cited in the original publication. Where no original material remains, a neotype is designated (Articles 9.7) from material not used by the original author. The first author to designate a lectotype or neotype for a particular name must be followed (Article 9.19) unless such a specimen is shown to be in conflict with the protologue (everything associated with the name at its valid publication); in that case the lectotype or neotype may be superseded (Articles 9.18, 9.19). Thus, Sarjeant (1984a) designated a lectotype for Gonyaulax (now Cribroperidinium) granulatum because the holotype had disintegrated. Brenner (1988) argued that the lectotype designated by Sarjeant was not conspecific with the holotype, and so designated as lectotype the specimen illustrated in Brenner (1988, pl.1, figs.3a–c). Inevitably, such debates involve subjective taxonomy. Authors who agree with Brenner must adhere to Brenner's lectotype; authors considering the holotype and both lectotypes to be conspecific are obliged to adhere to Sarjeant's lectotype.

Other sorts of type are accommodated in Article 9. Article 9.6 allows for paratypes, which are specimens cited in the protologue other than the holotype: the article does not specify that such a specimen needs to have been cited as a paratype in order to be considered one. Paratypes have no definitive nomenclatural role, although they are potential lectotypes if the holotype is lost. The term "isotype" has been used by some palynologists (e.g., Drugg, 1978). According to Article 9.4, an isotype is "any duplicate of the holotype". As with the broad definition of the word "specimen" in Article 8.3, the word "duplicate" in Article 9.4 is tacitly underpinned by genetic identity in a modern botanical context. Hence, the term isotype should be avoided in a fossil context. A syntype is any specimen cited in the protologue when no holotype has been designated (Article 9.5); hence this term is applicable only for names validated prior to 1958, when designation of holotypes became mandatory (see below).

An epitype is a specimen selected to serve as an interpretative type when the holotype, lectotype or neotype is "demonstrably ambiguous" (Article 9.8). Article 9.20 specifies that the author who first designates an epitype must be followed, and a new epitype may be designated only if the original epitype is lost or destroyed. As with other kinds of type, an epitype is not validly published unless its repository is specified (Article 9.19). As far as we are aware, no epitypes have yet been designated for fossil dinoflagellates. However, this device may prove a useful addition to the "tool box" in helping to solve some difficult taxonomic issues related to fossil dinoflagellates.

Fensome et al. (1990) and Fensome et al. (1998a) identified examples among acritarchs where an author listed a holotype in the text but did not specify which of the illustrations represented that specimen. The name Moyeria uticaensis Thusu, 1973 is an example. Fensome et al. (1990) faced a quandary as to whether such a name was validly published: they decided that it was not, since in effect no useful holotype had been designated. To resolve this issue, Fensome et al. (1998a) proposed new articles, incorporated in the St. Louis Code (Greuter et al., 2000) and now Articles 9.15 and 43.3. Article 9.15 effectively states that such a name, if published before 2001, should be considered as validly published, but one of the illustrated specimens should be designated as a lectotype until the identity of the holotype (if represented among the illustrations in the protologue) is confirmed. Hence, the name Moyeria uticaensis was validly published in 1973. Article 43.3 indicates that, after 2000, at least one illustration must be identified as the holotype: hence, if published now with the same material, Moyeria uticaensis would not be validly published.

Article 10.1 states that: "The type of a name of a genus or any subdivision of a genus is the type of the name of a species ...." This article, in conjunction with Article 7.2 on the permanence of types, implies that the type of a generic name remains the holotype of the name of the "type species" as designated by the author of the generic name. For example, Duxbury (1983, p.58) designated Cepadinium variabile as the "type species" of Cepadinium. Lister and Batten (1988b, p.43) considered Cepadinium ventriosum to be a taxonomic synonym of Cepadinium variabile. Since Cepadinium ventriosum is the senior name, it becomes the correct name for the "type species" of the genus Cepadinium. However, the nomenclatural type of the generic name Cepadinium remains the holotype of Cepadinium variabile (Duxbury, 1983, pl.9, fig.8; text-fig.27A–E). Article 10.1 also notes that "For purposes of designation or citation of a type [of a genus], the species name alone suffices ...." However, because the identity of the generic type has sometimes been misconstrued in the fossil dinoflagellate literature, we suggest that citing the type specimen of a genus rather than the correct name for the "type species" avoids confusion and misunderstanding. Article 10.6 indicates that the type of a name of a family or any subdivision of a family is the same as that of the genus on which its name is based. The same is true for taxa above the rank of family that are based on generic names (Article 10.7).

Articles 11 to 12 deal with priority. Each taxon of family or lower rank can bear only one correct name (Article 11.1). Of importance for fossil dinoflagellates is the second sentence in Article 11.1, which states: "However, the use of separate names is allowed for fossil-taxa that represent different parts, life-history stages, or preservational states of what may have been a single organismal taxon or even a single individual." In the past such variants were covered under provisions for form-, organ- and morphotaxa, but these terms have now been dropped in favour of a general reference to fossil-taxa. What this means is that a single biological taxon (however that may be defined) may have separate "extant" and "fossil" names (if the latter is based on a fossil specimen representing, say, a particular life-cycle stage such as a cyst). An example involves the species names Pyrophacus steinii and Tuberculodinium vancampoae: the former is typified by a living dinoflagellate, and the latter is based on a fossil cyst. The provision of Article 11.1 allows for an individual author to decide whether to treat the two generic names as taxonomic synonyms or to retain both separately. In the Index we retain all fossil-cyst based names separately from any known motile equivalents, following the generally accepted practice of dual nomenclature for dinoflagellates (Head et al., 2016). This is an excellent example of the flexibility in well-considered nomenclatural rules allowing for freedom in taxonomic decision-making. Not all nomenclatural rules are so well-considered!

At family to generic rank, the correct name is the earliest legitimate name at that rank (Article 11.3). For each species, subspecies, variety and form, the correct name is the combination of the final epithet of the earliest legitimate name at that rank (except for autonyms — Article 11.6 -- and a few other specified cases) combined with the correct name of the genus or species to which it is assigned (Article 11.4). In cases of equal priority, the first effectively published choice establishes priority (Article 11.5). The order in which names appear in an individual publication has no bearing on priority. The name Hystrichosphaeridium recurvatum subsp. polypes was proposed by Cookson and Eisenack (1962b) and was later raised to specific rank, as Polysphaeridium? polypes, by Davey and Williams (1966b). Two years earlier, Tasch in Tasch et al. (1964) had proposed the species name Hystrichosphaeridium unituberculatum, which is now considered synonymous with Polysphaeridium? polypes. Unfortunately, since "unituberculatum" was proposed at species rank in 1964 and "polypes" was not raised to species rank until 1966 (although proposed at subspecific rank in 1962), the more cumbersome epithet has to have priority over the more elegant one at species rank, as Kiokansium unituberculatum.

Article 11.7 states that "... names of fossil-taxa (diatom taxa excepted), compete only with names based on a fossil type." This is followed by Article 11.8, which states "Names of organisms (diatoms excepted) based on a non-fossil type are treated as having priority over names of the same rank based on a fossil type". As pointed out by Head et al. (2016), Article 11.8

"... is meant to address the priority of names based on a non-fossil type that are considered to be synonyms of those based on a fossil type when these names are applied to a non-fossil taxon. However, it could be interpreted to mean that a name based on a non-fossil type must also be applied to a fossil-taxon if both non-fossil and fossil-taxa are considered equivalent, such as when they represent different parts of the same life cycle. This would then be at odds with dual nomenclature and potentially contradict Art. 11.7."

Hence, Head et al. (2016) proposed an amendment of Article 11.8, as follows: "Names of organisms (diatoms excepted) based on a non-fossil type are treated as having priority over names of the same rank based on a fossil type where these names are treated as synonyms for a non-fossil taxon" (italics added here to indicate the additional phrase). If this amendment is accepted (ultimately at the 2017 International Botanical Congress), it will clarify and confirm the use of dual cyst (fossil) and motile nomenclature for dinoflagellates. For the purposes of this edition of the Index, we interpret Article 11.8 in the sense of the new proposed amendment, as we did in previous editions of the Index. Head et al. (2016) propose a new example to be added under Article 11.8. This example involves Votadinium calvum, which was proposed by Reid (1977) as a new fossil-species, acknowledging that it is the cyst of the extant species Peridinium oblongum. Votadinium calvum can be used as the correct name for the cyst because it has a fossil type and does not compete for priority with Peridinium oblongum.

Article 13.3 states that "For nomenclatural purposes, a name is treated as pertaining to a non-fossil taxon unless its type is fossil in origin. Fossil material is distinguished from non-fossil material by stratigraphic relations at the site of original occurrence." Thus, to paraphrase interpretively, a specimen is a fossil for nomenclatural purposes if it is found in strata. For example, based on this definition, and following Head et al. (2001) and Head (2003a), we consider the name Echinidinium granulatum to have been not validly published in its original proposal by Zonneveld (1997). The holotype is from a sediment trap and does not have a stratigraphic context; hence it must be treated as extant, its name (at the time of its proposal) requiring a Latin diagnosis. However, Echinidinium bispiniformum has a holotype from ocean floor sediment and has a stratigraphic context; hence it may be treated as a fossil, its name not requiring a Latin diagnosis for validation (Head, 2003a, p.171–172).

Article 12.1 states that: "A name of a taxon has no status under this Code unless it is validly published ...." Thus, only validly published names can be considered legitimate, illegitimate, correct, or for priority. Limitation of priority is covered in Articles 13 to 15. According to Article 13.1f, only names of fossil plants published after 1820 can be considered as validly published. Fortunately, this includes all names of fossil dinoflagellate taxa.

Conservation of names against others that would otherwise have priority is dealt with in Article 14. Names can only be conserved through submission to the General Committee (normally via a proposal in the journal Taxon), which refers the proposal to the appropriate subcommittee: in the case of fossil dinoflagellates this is the Committee for Fossil Plants. If recommended at the committee stages, proposals for conservation of names must be subjected to a decision of an International Botanical Congress (Article 14.14). Conservation cannot be achieved by individual taxonomists in general publications. Davey (1978) proposed in the general literature that the dinoflagellate generic name Tenua be "conserved" with a different type to that proposed by Eisenack (1958a), who first used the generic name Tenua. However, Davey's proposal is not in accordance with Article 14, and Tenua Davey (with the holotype of Tenua rioultii as type) must be considered an illegitimate junior homonym of Tenua Eisenack (with the holotype of Tenua hystrix as type). Similar situations surround the generic names Aiora and Compositosphaeridium. Among dinoflagellates, the family name Rhaetogonyaulaceae (Fensome et al., 1998c) and the generic name Diphyes (Harris and Fensome, 2000) have been formally conserved and are listed in the Code. Article 15 deals with sanctioned names, a concept that does not (yet) affect fossil dinoflagellates.

Nomenclature of Taxa According to their Rank

Articles 16 to 28 deal with the nomenclature of taxa in relation to their rank. Articles 16 to 19 are concerned with taxa above generic rank. Articles 20 to 22 cover names of genera and their subdivisions above the rank of species. Article 20.1 specifies that the name of a genus is a noun or a word treated as such; it must not coincide with an active Latin morphological term (Article 20.2). A generic name must not consist of two unhyphenated words (Article 20.3). Thus, Ovum hispidum is not an acceptable generic name; unhyphenated multiple word generic names apparently are not to be considered valid in their initial publication, though they may subsequently be made acceptable by the addition of a hyphen. Recommendation 20A encourages authors of generic names to use Latin terminations, to avoid names that are not adaptable to Latin, that are long, that are of mixed language, that are similar to a contained species name, and that are dedicated to individuals outside natural science.

Article 21.1 indicates that the name of a subdivision of a genus is a combination of a generic name and a subdivisional epithet, with a connecting term (e.g. "subgenus") to denote rank. Hence Protoperidinium subgenus Archaeperidinium is a proper rendition of the subgeneric name. When a specific epithet is added and the subdivisional epithet is deemed necessary, the subdivisional epithet should be placed in parentheses: for example, Protoperidinium (Archaeperidinium) minutum or Protoperidinium (subgenus Archaeperidinium) minutum are both acceptable (Recommendation 21A).

Under the provisions of Article 22.1, the name of any subdivision of a genus that includes the type of the genus is an autonym and repeats the generic name as its epithet; it is not followed by an author citation. An example is Protoperidinium subgenus Protoperidinium.

Article 23 deals with the names of species. Article 23.1 states that the name of a species is a binary combination consisting of the name of the genus followed by a single specific epithet. (Note that the term epithet refers to part of a name: thus, for Oligosphaeridium complex, Oligosphaeridium is the generic name, Oligosphaeridium complex is the specific name, and complex is the specific epithet. An epithet cannot stand alone.) The specific epithet can be in the form of an adjective (e.g. Kallosphaeridium granulatum) or a noun in the genitive (e.g. Cribroperidinium wilsonii) or in apposition (e.g. Trichodinium castanea). If an adjective and not a noun, a specific or infraspecific epithet must agree grammatically with the generic name, as in Riculacysta perforata (Article 23.5; see also Orthography and Gender below). Epithets not conforming with this rule are to be corrected; in the Index we treat such corrections as typographic errors and ordinarily make the changes without comment unless there are complications regarding the etymology or past understandings of it. If an epithet is a noun in apposition (N.I.A.), its ending is not changed to agree with the gender of the generic name, as for example with Cordosphaeridium cantharellus (the epithet referring to a specific type of mushroom). If the specific epithet is not of a single word, it can be considered valid in the initial publication (in contrast to the situation for generic names) but the words must be united or hyphenated in subsequent use if they were not originally thus proposed. An example of a name with a hyphenated epithet is Subtilisphaera pontis-mariae.

Article 23.4 states that a specific epithet may not be a tautonym — i.e. repeat exactly the generic name. Thus, the specific name Galea galea is not validly published, even if the generic name Galea were not a homonym. (This contrasts with the International Code of Zoological Nomenclature where such tautonyms are acceptable: e.g. Bison bison.) Recommendation 23A involves similar exhortations to those listed under Recommendation 20A above.

Names of taxa below the rank of species (infraspecific taxa) are covered in Articles 24 to 27. Article 24.1 states that the name of an infraspecific taxon is a combination of the name of a species and an infraspecific epithet, these being connected by a term denoting the rank (e.g. subspecies, varietas, forma). Article 24.2 notes that infraspecific epithets are formed in the same way as specific epithets: for example, where adjectival, they must agree grammatically with the generic name (e.g. Impagidinium paradoxum subsp. granulatum).

Article 26.1 stipulates that the name of any infraspecific taxon which includes the type of the species is an autonym and must repeat the specific epithet, but is not followed by an author's name. Article 26.3 notes that the first valid publication of a name of an infraspecific taxon that does not include the type of the species automatically establishes the corresponding autonym. Thus, when Yun Hyesu (1981) published the name Xenascus ceratioides subsp. procerus, which was the first subspecies proposed in this species, Xenascus ceratioides subsp. ceratioides was automatically established. Autonyms are indicated throughout the Index for species in which at any given time there has been a validly published infraspecific taxon. Thus, the entry for Apectodinium homomorphum includes an entry for the autonym Apectodinium homomorphum subsp. homomorphum, even though no other infraspecific taxa are now included in Apectodinium homomorphum. In such a situation, the autonym becomes (perhaps temporarily) redundant. A new infraspecific taxon is appropriately compared only with other infraspecific taxa (even if there is only the autonym), rather than with the species.

Effective Publication

Articles 29 to 31 deal with effective publication. Article 29.1 states that publication is effected by distribution of printed matter to the general public "or at least to scientific institutions with generally accessible libraries." However, Articles 30.4 and 30.5 permit "indelible autograph" prior to 1953. Article 30.1 stipulates that publication is not effected by communication of new names at a public meeting, by the placing of names in public collections, by the issue of microfilm, or via electronic material other than that specified in Article 29.1.

New in the Melbourne Code is an addition to Article 29.1 that states: "Publication is also effected by distribution on or after 1 January 2012 of electronic material in Portable Document Format (PDF ...) in an online publication with an International Standard Serial Number (ISSN) or an International Standard Book Number (ISBN). Article 30.2 specifies that an electronic publication is not effectively published if it is a preliminary version of something finalized later. The content of an electronic publication must not be altered after it is effectively published (Article 30.3). In preparing new entries for DINOFLAJ3, and hence this version of the Index, we encountered issues that illustrate the potential pitfalls of interpreting new rules such as those concerning electronic publishing in the Melbourne Code. The new genus Bianchina is proposed in the journal Palynology and first came to our attention in a PDF sent to us by the author, Poul Schiøler. The PDF appears essentially final, and the author has fulfilled all the conventional requirements for valid publication. However, the PDF bears the date 2015 and the pagination 1–6 (with the new genus proposed on pages 3 and 5). A little research involving "insider" connections confirmed that this pagination is not final and that the paper would be included as pages 406–412 in an issue of Palynology to appear in later 2016. Initially we considered Bianchina (and its single contained species Bianchina hieroglyphica) to be not effectively published because it was proposed in a non-final PDF — the pagination not being final. However, in discussion with Patrick Herendeen, a co-author of the Melbourne Code, we learned that during deliberations for the compilation of the Melbourne Code, final pagination was not considered a requirement for effective publication and was in fact regarded as "aesthetic and not substantive". While we go along with this decision apparently accepted among the nomenclatural hierarchy, and recognize the value of prompt publication of scientific data, we think it unfortunate that the article is not clearer (apparently "final" does not mean "final") and we are concerned about the confusion that will ensue. Thus, Bianchina was effectively published on pages 3,5 of a PDF of a paper that was posted online in 2015. The article will be part of an issue of Palynology to appear in its entirety and printed as a hard copy in later 2016, the article by Schiøler and containing Bianchina bearing the pagination 406–412. In future, the latter pagination will be the one referred to in the literature, but it will not be the formal pagination for effective (and valid) publication.

Another innovation in the Melbourne Code of potential importance (and confusion) to fossil dinoflagellate nomenclature is Article 30.8. This states: Publication on or after 1 January 1953 of an independent non-serial work stated to be a dissertation submitted to a university or other institute of education for the purpose of obtaining a degree does not constitute effective publication unless the work includes an explicit statement (referring to the requirements of the Code for effective publication) or other internal evidence that it is regarded as an effective publication by its author or publisher." Presumably, "dissertation" can be taken to be a synonym of "thesis" in this context. This new ruling may affect some names in this version of the Index that have been considered until now effectively published and consequently legitimate. For example, those introduced in the dissertation by Agelopoulos (1967), which has been considered effectively published supposedly in consideration of its broad distribution. Note 4 following Article 30.8 indicates that the presence of an ISBN number or a statement of the name of the printer, publisher, or distributor in the original printed version is regarded as internal evidence that the work was intended to be effectively published. In our view, Note 4 will cause confusion, especially regarding the statement of a printer's or related name. Moreover, the question arises as to whether theses that contain such indications should be considered effectively published; presumably, Article 29.1 would need to be considered in this context. Recommendation 30A notes that when publications exist only as printed matter, they should be deposited in "at least ten, but preferably more" generally accessible libraries". We have not made any changes in reaction to the present version of Article 30.8.

The date of effective publication is the date of availability as defined in Article 29 and that, in the absence of other proof, the date on the publication must be accepted (Article 31.1). When a publication is issued as both electronic material and printed matter, they must be treated as effectively published on the same date unless the dates of the versions are different (Article 31.2). Commonly, the electronic version is available at an earlier date than the printed version, as is the case with Schiøler (2015), as discussed above. In such cases, the date of effective publication will be that of the electronic publication. Article 31.3 clarifies that the date of effective publication can be that the distribution of separates (reprints) if earlier than the containing issue of the journal (echoing the case of Bianchina above and presumably with final pagination unnecessary). An example involves the fossil dinoflagellate taxa Quinquecuspis and Trinovantedinium concretum. Head (1993) contended that Quinquecuspis was not validly published by Harland (1977b) because he designated as its type Trinovantedinium concretum, which Head thought was not effectively published until 1978. However, although the journal in which Reid's paper appeared did indeed not come out until 1978, preprints of Reid's paper did appear in 1977 (P.C. Reid, personal communication, 1997).

Valid publication

Articles 32 to 45 deal with general provisions for valid publication. While the conditions for valid publication remain closely similar to those in previous versions of the I.C.B.N., the order and arrangement of Articles in the Melbourne Code (I.C.N.) is significantly different. According to Article 32.1, in order to be validly published, a name of a new taxon (other than an autonym) must be effectively published and have an acceptable form (for example, it must be in the Latin alphabet). Article 32.2 stipulates that use of incorrect Latin endings to epithets does not affect validity or authorship, but the endings should be corrected. The date of a name is that of its valid publication (Article 33.1). Prior to 1973, when conditions for fulfilment for valid publication are met in stages, the date of valid publication is the date when the final condition is met; after 1972, for a name to be validly published full and direct reference needs to be made in the validating publication to all places where the various elements have been fulfilled. The generic name Brigantedinium is a good example. It was not validly published in Reid (1977) since the type species, Chytroeisphaeridia simplicia Wall 1965b, was not validly published; Wall (1965b) had not provided a Latin diagnosis for Chytroeisphaeridia simplicia, a requirement since, although a cyst species, it was based on living material. Harland and Reid in Harland et al. (1980) provided a Latin diagnosis for the species, but did not validate the generic name Brigantedinium since they did not directly cite the Latin diagnosis provided for it by Reid (1977). It was not until Lentin and Williams (1993) brought all the pieces of the puzzle together that the names Brigantedinium and Brigantedinium simplex became validly published. (Although Wall, 1965b, had proposed the epithet originally as "simplicia", when eventually Lentin and Williams (1993) validly published the name, they rendered the epithet as "simplex", which is thus correct.) Article 35.1 specifies that the name of a taxon below the rank of genus is not validly published unless the name of the genus is also validly published. Thus, the name Palaeoperidinium muriciforme Conrad, 1941 was not validly published since the generic name Palaeoperidinium Deflandre, 1934 ex Sarjeant, 1967b, was not validly published until 1967. Note that species names attributed to validly published but illegitimate generic names (for example Albertia recticornis Vozzhennikova 1967) are validly published (Albertia in the example being a validly published name but an illegitimate junior homonym).

A combination is not validly published unless the final epithet is definitely associated with the genus or species to which it belongs (Article 35.2). Thus, in the Fensome and Williams (2004) Index, where we listed names within a genus by final epithet, for new combinations and other nomenclatural novelties, we deliberately used the full name of the taxon somewhere in the entry. Generic abbreviations are allowed in this context (but not recommended by us). Article 36.1 specifies that a name is not validly published when it is: not accepted by the author; proposed provisionally in anticipation of future acceptance; cited merely as a synonym; or merely mentioned as a subordinate taxon within a discussion of another taxon. Thus, the name Deflandrea eocenica was not validly published in Balteş (1969), since he considered it a provisional name. The correct citation is Deflandrea eocenica Balteş, 1969 ex Lentin and Williams, 1973. Bujak (1994, p. 119) stated that "Stover and Williams (in press) erected the genus Enneadocysta to accommodate ... species ... which have a partiform hypocystal configuration, with processes on paraplates 6'", 2"" and 1ps. They designated Enneadocysta pectiniformis (Gerlach) Stover and Williams as the type species." Bujak's paper represents the first published mention of the generic name Enneadocysta, since the paper by Stover and Williams did not appear until 1995. In most respects, Bujak fulfilled the requirements for validating the name Enneadocysta, providing a description, albeit brief, and indicating a type. However, since he was clearly mentioning the generic name in anticipation of Stover and Williams' paper, following Article 34.1b the name Enneadocysta was not validly published in Bujak (1994) and is correctly cited as Enneadocysta Stover and Williams, 1995. Similar situations surround the original publication of the names Tehamadinium and Chiropteridium lobospinosum. Article 36.1 also makes clear that names published with an indication of taxonomic doubt, such as a question mark, but otherwise in accordance with the Code, are validly published.

After 1952, the rank of a new name must be clear (Article 37.1). The name of a new taxon must also be accompanied by a description (any morphological statement) or diagnosis (a statement of the morphological features that distinguished the taxon form other taxa — Article 38.2) or a reference to such (Article 38.1). Article 38.5 specifies that the names of a genus and species can be validated simultaneously provided that the genus is monotypic at the time of validation. Thus, Palynodinium and its "type species" Palynodinium grallator were both validly published by Gocht (1970a), since Palynodinium was monospecific, even though Gocht gave only a diagnosis for Palynodinium grallator and did not separately describe the genus. Prior to 1908, an annotated illustration is acceptable in place of a written description or diagnosis (Article 38.7).

Article 39.1 deals with language of descriptions, but defers the language to be used for fossils and algae to later articles. Any name for a new taxon published after 2011 must have an English or Latin description or diagnosis or reference to such (Article 39.2) — prior to 2012, most groups governed by the Code had to have Latin descriptions, but not fossils (see below). After 1957, designation of the type of a new name of generic rank or lower is a requirement (Article 40.1). For the name of a genus, this can be reference to a species name, or the holotype of a species name (Article 40.3). After 1989, indication of a type must include the word "typus" or equivalent (Article 40.6). The generic name Kisselovia was proposed by Vozzhennikova (1963), who indicated a "type species" (Kisselovia ornata) but did not provide a description for that species. Hence, effectively, no type was designated in 1963 for Kisselovia. Vozzhennikova (1967) fulfilled the requirements for valid publication of the name of the proposed "type species", including the provision of a description and the designation of a type, thus also validating the generic name (with the spelling Kisselevia).

After 1989, the repository of the type must be specified (Article 40.7). Thus, the specific name Fibrocysta prolixa Harker and Sarjeant in Harker et al., 1990 was not validly published since those authors did not indicate where the holotype is lodged. This oversight was corrected in Harker and Sarjeant (1991). Therefore, the correct citation for the name of this species is Fibrocysta prolixa Harker and Sarjeant in Harker et al., 1990 ex Harker and Sarjeant, 1991, or more simply but less informatively Fibrocysta prolixa Harker and Sarjeant, 1991. Fensome et al. (1998b) noted, in correspondence with J. Jansonius, that the Chair of the then Code Editorial Committee, W. Greuter, considered that "the intent of [Article 40.7] is not to make deposition of types in a public herbarium mandatory, but to force authors to make the whereabouts of their types publically known." Greuter remarked also that the Article does not specify "public" herbarium, and he implied that reference to a private herbarium (i.e. collection) would fulfil this requirement of the Code. Fensome et al. (1998b) also suggested that if an author does not directly (i.e. fully) cite a repository but does give specimen numbers including abbreviations that clearly refer to a particular institute or collection (e.g. BS or BSIP for Birbal Sahni Institute of Palaeobotany), this is acceptable under Article [40.7]. This agrees with the spirit of Article 40.7, Note 4, which states that "Specification of the herbarium or institution may be made in an abbreviated form ...."

An additional requirement for valid publication of a new combination or replacement name is a citation to the basionym (the original version of the name of a taxon) (Article 41.1). After 1952, this citation must be a full and direct reference to its author and place of valid publication, with page or plate reference and date (Article 41.5). We interpret this to mean also that a full reference to the relevant publication must appear in the reference list of the paper in which the proposal is made, not a blanket reference to an earlier compendium, such as Fensome and Williams (2004) (cf. Article 41.7). Thus, the combination Stiphrosphaeridium dictyophorum (Cookson and Eisenack, 1958) Davey, 1982b, was not validly published in Davey (1982b), since although he provided page and plate references and a date, he did not provide a reference for Cookson and Eisenack (1958) in his reference list. The correct citation is Stiphrosphaeridium dictyophorum (Cookson and Eisenack, 1958) Lentin and Williams, 1985, since a complete reference to the protologue was given by the latter authors. However, errors in citation do not invalidate such nomenclatural proposals (Article 41.6).

After 1995, in order to be validly published, the name of a new fossil-taxon must be accompanied by a Latin or English description or diagnosis (Article 43.1). Thus the name Pervosphaeridium septatum, proposed in Slimani (1996), was not validly published since that author did not provide a description or diagnosis in Latin or English. Fossil taxa named prior to 1996 can be accompanied by a description or diagnosis in any language (Note 1). Article 43.2 stipulates that after 1911 the name of a new fossil-taxon of generic or lower rank must be accompanied by an illustration or reference to such. And as already noted, according to Article 43.3, after 2000 the name of a new fossil-species or infraspecific fossil-taxon is not validly published unless at least one of the validating illustrations is identified as the type.

As dinoflagellates are algae, aspects of the Code relating to that group as well as to fossils are of significance here. To be valid, the name of a non-fossil alga published between 1958 and 2011 inclusive must have a Latin diagnosis (Article 44.1), and from 1958 must be accompanied by an illustration (Article 44.2). There has been some confusion over what constitutes a fossil. Harland and Reid in Harland et al. (1980, p.223) considered that the name of a "Recent" species, Omanodinium alticinctum, was not validly published since its author (Bradford, 1975) did not provide a Latin diagnosis. However, the type is from not-avowedly living material and derived from sediments (i.e. having a stratigraphic context — see comments related to Article 11.7 above), and hence can appropriately be considered as a fossil. Thus, as noted by Lentin and Williams (1981), no Latin diagnosis or description of that name was required for valid publication.

Article 45.1 deals with names originally established under other codes, primarily the ICZN. It states that such a name need satisfy only requirements of the other code to be validly published under the I.C.N. Thus, many early names for fossil dinoflagellates were established under the ICZN. An example is the extant dinoflagellate genus Scrippsiella Balech 1959, which was "validly published" under the ICZN; when this genus is treated under the I.C.N. its name does not require further validation, regardless of the absence of a Latin diagnosis. The reverse situation also applies and this caused some notable re-interpretations in the 1998 edition of the Index. Thus the generic name Hystrichosphaera was "not validly published" in Wetzel (1932; 1933b), because no type was designated — a necessity since Wetzel was treating his fossils as protozoa and was using zoological nomenclature (ICZN Article 69). The name Hystrichosphaera was unwittingly validated by Deflandre (1937b) who designated a type. This re-interpretation changed the date of valid publication of several specific names: for example, Hystrichosphaera cornigera Wetzel, 1933b ex Deflandre, 1937b was cited in Lentin and Williams, 1993 as Hystrichosphaera cornigera Wetzel, 1933b.

Citations

Articles 46 to 50 deal with citations. Article 46.1 states that in some publications "... it may be desirable, even when no bibliographic reference to the protologue is made, to cite the author of the name ...." It is important to emphasize here the use of the word "may" in Article 46.1 — it is not a rule that authorship must be cited. Although useful, authorship citations can make text more difficult to read, and hence authors are increasingly including nomenclatural authorships in an Appendix (e.g. Schiøler et al., 1997) — a practice that we encourage.

Article 47.1 indicates that a change of a taxon's diagnostic characters (or, by implication, description) or circumscription "... does not warrant a change of the author citation." Recommendation 47A1 continues this theme by noting that, when such an alteration "... has been considerable, the nature of the change may be indicated by adding such words as ... "emendavit" (emend.) followed by the name of the author responsible for the change ..." (italics added here). Hence, an "emendation" is not a formal nomenclatural device (actually, it is not nomenclatural at all, but a taxonomic device), and an emending authorship is at no time part of the formal name of the taxon. An emendation should be cited for information purposes only — and generally only if the author making the citation agrees with the intent of the emendation. Long strings of cited emendations incorporated as part of a taxon's name should generally be avoided. In the Index, we list only those emendations avowedly acknowledged by the author at the time of the revision, and cite them separately from the formal nomenclatural authorship. We include as emendations cases where an author has used an equivalent term such as "revised description". We recommend that if authors feel they have something significant to say about the concept of a taxon, they should flag it as an emendation; otherwise important insights might be missed by later authors.

Article 48.1 stipulates that when an author adopts an existing name but explicitly excludes its original type, he has in effect created a later homonym of which he is sole author. Several examples, including Tenua Davey, 1978, were given above under the discussion of Article 14. For the citation of names at generic and lower rank, Article 49.1 requires the use of parentheses around the name of the author of an earlier, epithet-bringing legitimate name in cases of change of taxonomic rank or generic assignment. The name in parentheses is then followed, outside parentheses, by that of the author who effected the alteration in rank or assignment. For example, the species Cyclonephelium vitilare Cookson, 1965b was transferred to the genus Renidinium by Stover and Evitt (1978): the correct citation is Renidinium vitilare (Cookson, 1965b) Stover and Evitt, 1978. Hystrichosphaera ramosa var. granosa Davey and Williams, 1966a was transferred by Corradini (1973) to Spiniferites as Spiniferites ramosus var. granosus (Davey and Williams, 1966a) Corradini, 1973. Lentin and Williams (1973) raised this taxon to subspecific rank but retained it in Spiniferites. Thus, the correct citation is Spiniferites ramosus subsp. granosus (Davey and Williams, 1966a) Lentin and Williams, 1973. We emphasize that the protologue is the key reference for any taxon and should be fully referenced in taxonomic works; thus in our view the aforementioned species should not be cited as Renidinium vitilare (Cookson) Stover and Evitt, 1978; the key diagnostic information for this species is in Cookson (1965b).

Rejection of Names

Articles 51 to 58 deal with rejection of names. Article 52.1 states that a name is illegitimate if it was nomenclaturally superfluous when published — i.e. if the taxon to which the name was applied definitely included the type of another name, which ought to have been given priority. Thus, Agerasphaera Harland, 1979a is illegitimate since it is a nomenclatural junior synonym of Alisocysta Stover and Evitt, 1978, which has the same type.

However, Article 52.2 specifies that definite inclusion of the type of a name is effected, in part, by citation of the name itself "... unless the type is at the same time excluded either explicitly or by implication." In Fensome and Williams (2004) (and thus DINOFLAJ2), we invoked Article 52.2 to justify retention of the species name Votadinium calvum (and in consequence the generic name Votadinium), in future we may use a revised Article 11.8 (if ratified) to justify its acceptance (see discussion above). Lentin and Williams (1993) considered the name Votadinium calvum to be an illegitimate superfluous name (in the sense of Article 52.1), since in proposing the species as new, Reid (1977) considered it to represent the encysted stage of Protoperidinium oblongum; strict application of Article 52.1 thus prescribes that Votadinium calvum is a nomenclatural junior synonym of Protoperidinium oblongum, the two names referring to the same biological species according to Reid. However, as discussed above and by Head et al. (2016) duality of nomenclature is accepted practice for dinoflagellates. Since Reid (1977) clearly viewed the two names Votadinium calvum and Protoperidinium oblongum as representing distinct entities, one based on cysts, the other on the motile stage, and since he clearly did not propose the name Votadinium calvum to replace Protoperidinium oblongum, Fensome and Williams (2004) invoke Article 52.2 to retain the former name. Most names based on cysts are fossil and can be clearly retained under the I.C.N. as fossil-taxa, regardless of whether their motile equivalent is known.

Article 53.1 states that "A name of a family, genus or species ... is illegitimate if it is a later homonym, that is, if it is spelled exactly like a name based on a different type that was previously and validly published for a taxon of the same rank." An example is Albertia Vozzhennikova, 1967, a junior homonym of Albertia Schimper, 1837 and therefore an illegitimate name. Lentin and Williams (1976) thus proposed to replace it with the new name Alterbia, but while doing so inadvertently included the "type species" of the earlier generic names Senegalinium and Andalusiella. Following Article 52.1, therefore, Alterbia was a superfluous, and hence illegitimate, name. Consequently, Lentin and Williams (1985) proposed a second new name for Albertia Vozzhennikova, Alterbidinium, this time excluding the "type species" of Andalusiella and Senegalinium. Fensome et al. (1993b) considered the name Danea Morgenroth, 1968 to be a junior homonym of Danaea Smith 1793, an extant fern genus, and proposed the generic name Damassadinium as a replacement for Danea Morgenroth. However, we agree with the entry in the Index Nominum Algarum (http://ucjeps.berkeley.edu/cgi-bin/porp_cgi.pl?105660) that Damassadinium is an illegitimate superfluous name, as Danea Morgenroth is not an exact homonym of Danaea Smith; we have thus made the appropriate adjustments in in this version of the Index and DINOFLAJ3.

According to Article 55.1, a name of a species or subdivision of a genus may be legitimate even if its name/epithet was originally combined with an illegitimate generic name. Thus, Albertia curvicornis is a validly published name, even though the generic name Albertia Vozzhennikova is illegitimate.

Orthography and Gender

Articles 60 to 61 deal with the orthography of names and epithets. Some of the rules and recommendations are very hard to follow, especially for those of us without classical training. Article 60.1 specifies that the original spelling of a name or epithet is to be retained, except for, firstly, the correction of typographic or orthographic errors and, secondly, modifications indicated by standardizations specified in Articles 60.5 to 60.12. Article 60.2 states that the "original spelling" is the spelling of a name at its valid publication. Hence, the name Kisselevia is the correct version of the name as it was spelled at it the time of its validation by Vozzhennikova (1967), rather than Kisseljovia in Vozzhennikova (1961) and Kisselovia in Vozzhennikova (1963). Article 60.3 notes that the liberty of correcting a name is to be used with reserve, especially if it affects the first letter or syllable. According to Article 60.6, diacritical signs are not used in Latin plant names. In names "... drawn from words in which such signs appear, the signs are to be suppressed with the necessary transcription of the letters so modified ...." Thus, the specific name introduced by Morgenroth (1966a) as Impletosphaeridium krömmelbeinii is correctly cited as Impletosphaeridium kroemmelbeinii. The use of hyphens is treated differently depending on taxonomic rank. Article 60.9 specifies that use of a hyphen in a compound epithet is treated as an error to be corrected by deletion of the hyphen. "A hyphen is permitted only when the epithet is formed of words that usually stand independently, or when the letters before and after the hyphen are the same." Use of the word "epithet" implies that this article is dealing with names at species (or maybe subgenus) and lower rank. Applying this article to the species name Bonetocardiella ponce-de-leoni, we tentatively retain the hyphens as the three words would have presumably stood independently. Although not relating to dinoflagellates, but of interest as a palynological example, it has recently come to light that some well-used spore-based generic names were originally spelled with a hyphen — for example Cicatricosi-sporites. Although no palynologist as far as we know has used this spelling for decades, technically it is still the correct spelling. A proposal has been published to revise the Code so that hyphens in such generic names follow the same rule as specific epithets — that is that the hyphen be dropped in such cases (Anderson et al., 2016).

Article 60.12 states that "The use of an incorrect termination (for example -i, -ii, -ae, -iae, -anus, or -ianus ... is treated as an error to be corrected". Thus the name originally proposed as Canningia ringnesii Manum and Cookson, 1964, named after the Ringnes brothers, is correctly written as Canningia ringnesiorum Manum and Cookson, 1964. The species name Chatangiella bondarenkii (Vozzhennikova, 1967) Lentin and Williams, 1976, named after N.M. Bondarenko, is correctly cited as Chatangiella bondarenkoi (Vozzhennikova, 1967) Lentin and Williams, 1976. And we have changed the epithet proposed as Senoniasphaera whitenessii to Senoniasphaera whitenessensis because it is named after a place (White Ness) rather than a person.

Recommendations 60A through 60I provide further guidance on correct orthography. For example, Recommendation 60C.2 notes that personal names already in Greek or Latin, or possessing a well-established latinized form, should be given their appropriate Latin genitive, such as alexandri from Alexander, augusti from Augustus, martini from Martinus or Martin or linnaei from Linnaeus. To the present authors (and perhaps others lacking classical training), the limits of this recommendation are not clear, but we have tried to adhere to it in obvious situations, such as Achomosphaera neptuni, based in large part on advice from the late Jan Jansonius. According to Recommendation 60C.5a, "The Scottish patronymic prefix 'Mac', 'Mc' or 'M', meaning 'son of', should be spelled 'mac' and united with the rest of the name. However, this is a recommendation, not an Article, and the original spelling of the epithet must be followed. For example, with regard to the name Chatangiella mcintyrei, the preferred spelling of the epithet following Recommendation 60C.5a would be "macintyrei", but since the author, Nøhr–Hansen (1996), gave the epithet as "mcintyrei", the latter spelling is correct.

It is relevant to note again that specific epithets, if adjectival, must agree grammatically with the generic name (Article 23.5). However, when the specific epithet is a noun in apposition (N.I.A.), it is not to be changed as if it were an adjective, but stays in the nominative, as in Discorsia nannus (the epithet meaning dwarf). Recommendation 60G deals with the formation of compound epithets — i.e. those epithets that are derived from two or more words, for example perforoconum (as in Sentusidinium perforoconum). In this compound epithet, the first part is related to the Latin adjective "perforatus" (perforate) and the second part is derived from the Latin noun "conus" (cone). The recommendation is rather obtuse, but we follow Nicolson (1986, p.324), who averred that unless the original author indicates otherwise, it is general botanical practice to treat such compound epithets as adjectives, even though the last part (in this case "conus") may be a noun. Hence, "Sentusidinium perforoconum" is the correct orthography, rather than "Sentusidinium perforoconus"

Article 62 is concerned with gender. A generic name retains the gender assigned by botanical tradition. A generic name without a botanical tradition retains the gender assigned by its author. Thus, Hystrichokolpoma is regarded as neuter. For a further discussion of orthography in botanical taxonomic names, see Jansonius (1997a, b).

Key dates

Here are some key dates associated with the I.C.N.:

1820 onward — names for fossils can be considered (Article 13.1f)

1908 onward — an annotated illustration in place of written description or diagnosis not allowed (Article 38.7)

1912 onward — illustration required for new fossil-taxa of genus or lower rank (Article 43.2)

1953 onward — rank must be clear (Article 37.1)

1953 onward — for new combinations, etc., a full and direct reference to the basionym is required (Article 41.5)

1958 onward — designation of holotype necessary for valid publication (Article 40.1)

1958 onward — new taxa of living algae require an illustration (Article 44.2)

1973 onward — conditions for valid publication must be all met in one place (Article 33.1)

1990 onward — indication of a type must include the word typus or equivalent (Article 40.6)

1990 onward — the repository of the type must be specified (Article 40.7) in full or as abbreviation

1996 onward — each new fossil-taxon must be accompanied by a Latin or English description or diagnosis (Article 43.1)

2001 onward — for fossils, at least one illustration must be identified as the holotype (Article 43.3)

2012 onward — electronically published names considered for effective publication (Article 29.1)

2012 onward — all new taxa must have Latin or English description or diagnosis (as was already the case for fossils) (Article 39.1)

FORMAT

General Remarks on Format

As noted above in the Introduction, the three sections of the Index (Main Index, Appendix A and Appendix B) can be accessed as such in the left side-panel of DINOFLAJ3. This part of the panel also allows access to subsets of calcareous and siliceous dinoflagellates, which are part of the Main Index. Items in the Appendices are also indicated as such in the list of genera and taxa at other ranks in the upper part of the left side-panel.

With regard to reference citations, following Xu Zhaoran and Nicolson (1992), we give names of Chinese and Korean authors in full: i.e. "Mao Shaozhi" rather than just "Mao". We thus also cite Chinese names with family name first and personal name second ("Mao Shaozhi") as they themselves would cite the name, hence avoiding the nowadays common (but in our view discourteous) temptation to westernize the name ("Shaozhi Mao").

Throughout DINOFLAJ3, author citations are given as they appeared at publication. An example is Jiabo (1978). The word Jiabo, used on the publication, was given as a collective name for the authors. We were asked by He Chengquan, prior to publication of the 1981 Index, to list the individual contributors: thus, Bohaidina Jiabo would be cited as Bohaidina Sung Zhichen, He Chengquan, Qian Zeshu, Pan Zhaorin, Zheng Guoguang and Zheng Yuefang. Unfortunately, we could not accede to this request since, in accordance with I.C.N. (then I.C.B.N.) Article 46.2, we should maintain the integrity of the protologue, which cites the authorship as "Jiabo".

DINOFLAJ2 incorporated a suprageneric classification of dinoflagellates (fossil and living) based on Fensome et al. (1993b). This information is retained in DINOFLAJ3, but it is beyond the scope of the present update to revise the suprageneric classification, albeit much needed.

Entries

Taxonomic and nomenclatural information is accessed via the navigation panel at left, and entry can be made at one of several taxonomic ranks, of which the genus level can be considered a starting point. In each genus entry, the generic name is immediately followed by the authorship citation and, in a separate sentence, any emendations. Where the genus represents calcareous or siliceous fossils, there is a statement to that effect. Thus:

ORTHOCARINELLUM Keupp, 1987, p.41. Emendation: Kienel, 1994, p.37. Calcareous dinoflagellate genus.

This information is sequentially followed by information in the following categories, as appropriate: validity and legitimacy (including senior homonym), substitute name, nomenclatural history, senior synonym(s), junior synonym(s), junior homonym(s), other comments, and type. Subgenera and sections are treated in a similar way to genera, but species attributed to these are listed as formal entries under the genus, not under the subgenus or section. Beneath each genus entry is a list of all species names that have at some time or other been included in the genus, the currently correct ones in bold.

Entries for species can be accessed through clicking on a species name on the genus page, or via "species" on the navigation panel. For each species entry, the specific epithets is in bold, followed by citations for original and, where appropriate, validating or combining authors. There then follows information, where appropriate, on emendation(s), holotype, lectotype, neotype, validity and legitimacy (including senior homonym), substitute name, nomenclatural history (including retention and questionable assignment statements), senior synonym(s), junior synonym(s), junior homonym(s), motile equivalent, other comments, and age. The age cited for each species, unless otherwise specified, is that attributed to it in the protologue. It is not intended to be a full or up-to-date statement of the range of the species; users are advised to consult the literature for potentially more detailed and precise information. The letters "N.I.A." immediately before the age indicate that a particular epithet is a noun in apposition (see above and Glossary).

Infraspecific taxa are accessed similarly via listings in the species entries or via the navigation panel. The epithet is in bold and preceded by the name of the rank ("subsp.", "var.", "forma"). Except where a definite hierarchy of infraspecific taxa is clearly involved (e.g. Gonyaulacysta jurassica subsp. longicornis var. longicornuta), we treat all infraspecific taxa as being of equivalent rank. The format adopted for the infraspecific ranks is essentially the same as that for the specific entries, except in the case of autonyms. For each autonym, we give the word "autonym", emendation(s), holotype, lectotype, neotype, and nomenclatural history. If no other infraspecific taxa within a particular species are currently accepted, the phrase "Now redundant" will appear as part of the nomenclatural history. There is a tendency in the literature for autonyms and the taxa that they represent to be ignored or neglected. However, they are real entities — the subspecies, varieties and forms containing the type of the species — and should be referred to as such in descriptions and comparisons.

Names not enclosed by quotation marks are validly published, legitimate, and correct (in the sense of the I.C.N.). All other names are enclosed by quotation marks. For all names in quotation marks, one or more statements in bold type will explain the current status. Thus, under Pseudoceratium, there is:

"eopelliferum" Herngreen et al., 1994, p.386. Name not validly published: no description or illustration.

The statement of nomenclatural history of a particular taxon may include: a "NOW" statement, which indicates current assignment; a "sequencing" statement that provides the nomenclatural history in full; a "retention" statement if the taxon has been retained under a combination that was not the latest to be proposed; and a "questionable assignment" statement, discussed below. Thus the statement of nomenclatural history in the entry for Hystrichosphaeridium capitatum is:

NOW Prolixosphaeridium. Originally Hystrichosphaeridium, subsequently (and now) Prolixosphaeridium, thirdly Tenua Eisenack, fourthly Batiacasphaera.

And under Prolixosphaeridium capitatum:

Originally Hystrichosphaeridium, subsequently (and now) Prolixosphaeridium, thirdly Tenua Eisenack, fourthly Batiacasphaera. Lentin and Williams (1981, p.233) retained this species in Prolixosphaeridium.

The citation "Tenua Eisenack" is given to distinguish the name from its homonym, "Tenua Davey".

The sequencing statement for Achilleodinium biformoides is as follows:

Originally Hystrichosphaeridium, subsequently Baltisphaeridium (Appendix A), thirdly Hystrichokolpoma, fourthly (and now) Achilleodinium, fifthly Florentinia. Lentin and Williams (1981, p.2) retained this species in Achilleodinium.

The parenthetic statement after "subsequently Baltisphaeridium" indicates that the entry for Baltisphaeridium biformoides can be found in Appendix A.

Names or combinations that are not validly published or illegitimate are similarly indicated. Where a species has been questionably assigned to a genus, this is indicated in the "sequencing" statement and in a "questionable assignment" statement. For example, the entry for Canningia? granulata in part reads as follows:

Originally Canningia, subsequently (and now) Canningia?. Questionable assignment: Stover and Evitt (1978, p.25), as a problematic species.

Where taxa have changed rank, this is reflected in the "sequencing" statement. For example, the statement for Sophismatia crassiramosa is:

Originally Wetzeliella tenuivirgula var. crassoramosa, subsequently Wetzeliella tenuivirgula subsp. crassoramosa, thirdly Kisselevia tenuivirgula subsp. crassoramosa, fourthly Kisselevia crassoramosa, fifthly Charlesdowniea crassoramosa, sixthly (and now) Sophismatia crassoramosa.

In such cases, the full taxon names, rather than just generic names, are included for clarity.

In cases where a motile equivalent for a cyst can be identified, we have provided this information. For example, under the entry for Tuberculodinium vancampoae, we include the statement:

Motile equivalent: Pyrophacus steinii (Schiller, 1935) Wall and Dale, 1971, according to Matsuoka et al. (1989, p.94).

GLOSSARY

autonym: According to I.C.N. Article 26.1: "The name of any infraspecific taxon that includes the type of the ... legitimate name of the species to which it is assigned is to repeat the specific epithet unaltered as its final epithet, not followed by an author citation. .... Such names are termed autonyms ...." An autonym may be a subspecies, variety or form; and the taxon that an autonym represents may be referred to as the "type subspecies", "type variety" or "type form" of the species. Subspecific taxa not including the type species are most appropriately compared with the type infraspecific taxon, not with the species.

basionym: The first validly published, legitimate name of a taxon.

Code: An abbreviation for the International Code of Nomenclature for Algae, Fungi, and Plants (McNeill et al., 2012; the Melbourne Code). Previous editions of the Code were published as the International Code for Botanical Nomenclature (see Williams and Fensome 2016 for further discussion).

combination not validly published: statement used when a species or infraspecific taxon with a validly published basionym is assigned to another genus or species and the combination is not validly published.

comb. nov., combinatio nova: Latin, new combination: "... a combination ... validly published ... for the first time, and based on a previously ... validly published combination (basionym ...), from which the word peculiar to the taxon (epithet ...) is transferred ..." (Jeffrey, 1977, p.57).

compound name/epithet: A compound name or epithet is one that combines elements from two or more words, e.g. "conispiniferum" in Hystrichosphaeridium conispiniferum. Compound epithets for species and infraspecific taxa, regardless of whether their components are nouns or adjectives, are generally made to agree with the gender of the generic name. See further discussion under Orthography and Gender above.

correct name: "... the correct name of a taxon with a particular circumscription, position and rank is the legitimate name which must be adopted for it under the rules ...." (I.C.N. Article 6.6.) The one senior, validly published and legitimate name among a group of names, legitimate and validly published or otherwise, that are considered to be taxonomic synonyms.

description: "... a statement of the attributes of a specimen or taxon" (Jeffrey, 1977, p.58).

diagnosis: "... a statement of that which in the opinion of its author distinguishes the taxon from others" (I.C.N. Article 37.2). A statement, terse by comparison to a description, that is restricted to answering the question "How is this taxon different from other described taxa?"

emend., emendatus, emendavit, emendavunt: Latin: "... altered (by); "indicates a change in circumscription of a taxon without exclusion of the type of its name: the abbreviation emend. follows the authority [i.e. original author of the taxon] and precedes the name of the author who effected the change." (Jeffrey, 1977, p.59.) We prefer to use the English word "emendation". Especially in palynology, emendations have been cited as if they were part of the name of the taxon. However, emendations have no formal status under the I.C.N. (see discussion above relating to I.C.N. Article 47.1).

emendation: see "emend."

epithet: "... a word, other than a generic name or a term indicative of rank, forming part of a combination ...." (Jeffrey, 1977, p.59.) For example, in the name Gonyaulacysta jurassica subsp. desmos, the words "jurassica" and "desmos" are the specific and subspecific epithets respectively.

epitype: "... a specimen ... selected to serve as an interpretative type when the holotype, lectotype or ... neotype ..." or any protologue material are "... demonstrably ambiguous ..." (Article 9.8). Article 9.20 specifies that the author who first designates an epitype must be followed, and a new epitype may be designated only if the original epitype is lost, destroyed, or in conflict with the protologue.

ex: Latin: "... from, according to ... used to connect two author citations, the second of which validly published a name proposed but not validly published by the first." (Jeffrey, 1977, p.59.) For example, the authorship of the species Areoligera medusettiformis is "Wetzel, 1933b ex Lejeune-Carpentier, 1938[a]". The name Hystrichosphaera penicillata forma medusettiformis was not validly published in Wetzel (1933b); it was subsequently validated by Lejeune–Carpentier (1938a). It is technically correct, but less informative (and courteous), to give the citation as Areoligera medusettiformis Lejeune-Carpentier, 1938a.

form, forma: The rank of infraspecific taxa immediately below variety.

holotype: "... the one specimen ... used by the author, or designated by the author as the nomenclatural type" of a species or infraspecific taxon (I.C.N. Article 9.1).

homonym: "... a name identical in orthography with another (or treated as such ...) and based on a different type" (Jeffrey, 1977, p.61). For example, the dinoflagellate generic name Speetonia Duxbury, 1977 is a junior homonym of the coccolith generic name Speetonia Black, 1971. Names with similar pronunciation but different spellings are generally not considered to be homonyms; for example Danea Morgenroth, 1968 is not considered a homonym of Danaea Smith 1793.

I.C.B.N.: Previous editions of the I.C.N. (see below) were called the International Code of Botanical Nomenclature.

I.C.N.: The International Code of Nomenclature for Algae, Fungi, and Plants (Melbourne Code) (McNeill et al., 2012). See also I.C.B.N. Changes to a Code must be proposed to the General Committee, generally via publication in the journal Taxon. Proposals concerning fossils and (modern) algae are referred to special committees for the respective groups for consideration and recommendations. Changes to the Code, based on this process, must be validated at an International Botanical Congress, these being held usually every six years.

ICZN: International Code of Zoological Nomenclature (Ride et al., 2012).

illegitimate name: "... a validly published name that is not in accordance with the rules in such a way that it must not be taken into consideration for the purposes of priority (except for the purposes of homonymy ...) when the correct name of a taxon is being decided." (Jeffrey, 1977, p.65.) Note that names that are not validly published can be referred to as "not legitimate" but not "illegitimate". Illegitimate names cannot be re-used, since a homonym would be created; if a name is simply "not legitimate", it may be validated and thus rendered legitimate as long as it is neither a homonym nor includes the type of an earlier name.

junior homonym: "... the later [validly] published of two homonyms" (Jeffrey, 1977, p.61).

junior synonym, junior taxonomic synonym: see "nomenclatural synonym" and "taxonomic synonym".

lectotype: "... a specimen ... designated from the original material as the nomenclatural type ... when no holotype was indicated at the time of publication [or] when it is missing..." (I.C.N. Article 9.2).

legitimate name: a name "... that is in accordance with the rules ..." (I.C.N. Article 6.5). Note that legitimate in the sense of the I.C.N. is not the converse of illegitimate (which see).

misspelling: an unintentional, incorrect spelling of a taxon name.

name not validly published: a name that is not in accordance with Articles 32 to 45 of the I.C.N.

neotype: "... a specimen ... selected to serve as nomenclatural type as long as all of the material on which the name of the taxon was based is missing" (I.C.N. Article 9.7).

new combination: see comb. nov.

new name: "A new name published as a replacement name (... nomen novum) for an older name is typified by the type of the older name ..." (I.C.N. Article 7.4).

new species: a species name validly published for the first time.

N.I.A.: noun in apposition; refers to the use of the substantive as a specific or infraspecific epithet of a species name. The nominative orthography ("original correct spelling") of such an epithet is retained, regardless of the gender of the generic name — e.g. "Cordosphaeridium cantharellus" not "Cordosphaeridium cantharellum". ("Cantharellus" is a genus of mushroom — all generic names are nouns.)

nomenclatural synonym: a synonym of the same rank and based on the same type; in the ICZN the equivalent term is objective synonym. An earlier, validly published nomenclatural synonym is a "nomenclatural senior synonym" relative to a later, validly published nomenclatural synonym, which is thus a "nomenclatural junior synonym". (See also the discussion above under I.C.N. Article 52.)

nomenclatural type: "A nomenclatural type ... is that element to which the name of a taxon is permanently attached, whether as a correct name or as a synonym. The nomenclatural type is not necessarily the most typical or representative element of a taxon" (I.C.N. Article 7.2). See also "holotype" and "type".

nom. nov. subst. pro: Latin, a new name in substitution for. This Latin phrase is used in the publication in which the new name is proposed; subsequent publications should use the term "nom. subst. pro".

nom. nud., nomen nudum: Latin for "naked name"; a name that is not validly published. In DINOFLAJ3 we prefer the clearer equivalent "name not validly published".

nom. subst. pro: Latin, a name in substitution for. This Latin phrase is used to signify replacement names proposed in earlier publications. We prefer to use the term "substitute name" in this Index.

Now redundant: indicates an autonym that has been required in the past but is no longer needed because the species currently contains no other correct ("active") infraspecific taxa .

objective synonym: the ICZN term for a nomenclatural synonym. Also termed obligate synonym.

obligate synonym: see objective synonym.

original material: "... those specimens and illustrations ... upon which it can be shown that the description or diagnosis validating the name was based ..." (I.C.N. Article 9.3).

orthographic variant: an incorrect, but intentional spelling of a name, as opposed to an unintentional misspelling.

protologue: "... everything associated with a name at its valid publication, i.e. description or diagnosis, illustrations, references, synonymy, geographical data, citation of specimens, discussion, and comments" (I.C.N., footnote to Recommendation 8A.4.)

senior homonym: "... the earlier published of two homonyms" (Jeffrey, 1977, p.61).

senior synonym; senior taxonomic synonym: see nomenclatural synonym and taxonomic synonym.

sp. nov., species nova: Latin, new species; indicates a species name validly published for the first time.

stat. nov., status novus: Latin, new status; "... used in citation to indicate that a taxon has been altered in rank but retains in its name the epithet from its name in the former rank" (Jeffrey, 1977, p.69).

subjective synonym: the ICZN term for taxonomic synonym.

subsp.: subspecies: the rank of infraspecific taxa immediately below species.

substitute name: A replacement name substituting for an illegitimate name.

synonym: "One of two or more names applied to the same taxon" (Jeffrey, 1977, p.70). In DINOFLAJ3, without further qualifiers, "synonym" refers to a taxonomic synonym.

tautonym: a name of a species in which the specific epithet exactly repeats the generic name.

taxonomic synonym: a synonym based on a different type; in the ICZN the equivalent term is subjective synonym. An earlier taxonomic synonym is a "taxonomic senior synonym" relative to a later, validly published taxonomic synonym, which is thus a "taxonomic junior synonym". (The terms junior taxonomic synonym and senior taxonomic synonym are also used.)

type (of a genus): "The type of a name of a genus ... is the type of the name of a species ...." (I.C.N. Article 10.1.) See holotype.

type species: the now informal designation of the correct name of the species that includes the type of the generic name. See explanation of the symbols "*" and "+" below.

validly published: In order to be validly published, a name of a taxon (autonyms excepted) must be in accordance with I.C.N. articles 32 to 45. Requirements for the valid publication of a name include effective publication (Articles 29–31), the provision of a description or diagnosis or by a reference to a previously and effectively published description or diagnosis, and the designation of a type. For a more comprehensive summary of articles relating to valid publication, see above.

var., varietas: Latin, variety. The rank of infraspecific taxa immediately below subspecies.

*: species containing the type of the genus, as designated at the valid publication of the generic name.

+: the taxonomic senior synonym of the species name containing the nomenclatural type of the genus. Thus, correct (in the sense of the I.C.N.), but not the originally designated name of the "type species".