The genus Cyclidiopsis: an obituary.

Since its creation in 1917 the genus Cyclidiopsis, and its validity, has been a source of debate among euglenid taxonomists. While many authors have supported its legitimacy, various other authors have considered it to be a subgenus of Astasia or even promoted its complete dissolution. In this study, we have sequenced the small subunit and large subunit ribosomal DNA of Cyclidiopsis acus, the type species for the genus. Subsequent phylogenetic analyses showed that C. acus grouped with taxa from the genus Lepocinclis, which necessitated the removal of this taxon from Cyclidiopsis and into Lepocinclis as Lepocinclis cyclidiopsis nom. nov. After an extensive literature search it was determined that only two other previously described Cyclidiopsis taxa were morphologically distinct, and the rest were reassigned as synonyms of L. cyclidiopsis. These findings prompted a re-examination of the initial description of Cyclidiopsis, and it was determined that the morphological characters establishing the genus as a distinct group were no longer valid in light of current phylogenetic analyses and the emended generic description for Lepocinclis. Therefore, the remaining two taxa were formally moved to the genus Lepocinclis as L. crescentia comb. nov. and L. pseudomermis comb. nov.