Order Gonyaulacales diagnosis
|Citation: Gonyaulacales Taylor 1980.|
Diagnosis:Peridiniphycideans with a tabulation which accords with, or clearly derives from, a pattern in which one or both of the following arrangements occur: (a) the first apical plate (1\') or its homologue (*1\') is asymmetrical, its left lateral triple junction being higher (i.e. more anterior) than the right lateral triple junction; (b) there are two to four fundital plates - always the posterior intercalary plate (1p) and first antapical plate (1\'\'\'\') or their homologues (*1p, *1\'\'\'\'), sometimes the posterior sulcal homologue (*ps), and possibly in rare cases also the right sulcal homologue (*rs) or subdivisions of these plates. Among the fundital plates, 1\'\'\'\' (or *1\'\'\'\') is almost always larger and is in a clearly more dorsal position than the other(s).