Loricate choanoflagellates (Acanthoecidae) from warm water seas — a baseline study. I. Conioeca gen. nov. and Nannoeca Thomsen
Abstract
The main outcome of this and subsequent papers is to provide a baseline survey of heterotrophic protist diversity from warm water marine ecosystems, exemplified by loricate choanoflagellates (Acanthoecida). Loricate choanoflagellates are heterotrophic, nano-sized protists that are ubiquitous in marine and brackish water habitats. They dwell in a lorica formed by silicified costal strips organized in species specific patterns. The single anteriorly directed flagellum is surrounded by a collar formed by microvilli which together constitute the feeding apparatus. Keystone benefits from this warm water survey, which covers all three major oceans, is an improved understanding of global biogeographical patterns, and a further consolidation of the morphospecies matrix, that constitutes a highly essential reference framework for the current efforts to provide barcodes for as many species of loricate choanoflagellates as possible, based on e.g. single cell pipetting techniques. We describe here Conioeca gen. et sp. nov., which is so far distributionally confined to warm water habitats, and elaborate on the morphological variability encountered within the N. minuta complex. This leads to both the circumscription of a new N. minuta form A as well as the description of N. mexicana sp. nov.