Karenia concordia sp. nov. (Gymnodiniales, Dinophyceae), a new nonthecate dinoflagellate isolated from the New Zealand northeast coast during the 2002 harmful algal bloom events

Abstract

A new nonthecate dinoflagellate, Karenia concordia Chang & Ryan sp. nov., is described from a culture isolated during the October 2002 toxic outbreaks in the Hauraki Gulf, New Zealand. Typically, the conical epicone of the cell is dorsally convex and ventrally concave, giving it a ‘droop-nose’ look similar to the Concord supersonic aircraft. Karenia concordia may be separated from all the other closely related species by having a very long, straight apical groove which extends beyond the sulcal intrusion and towards the edge of the cingulum on the ventral surface; it is mostly hidden beneath a ‘flap’ of transparent membrane on the lower right margin of the right epicone. This is the longest apical groove found in the genus to date. Moreover, the groove is located within a ‘keel-like’ structure or crest which extends from the apex to the sulcal intrusion on the ventral surface of the cell. The position of the spherical nucleus in the cell is variable, but it is predominantly in the left hypocone.