Diaphanoeca W. Ellis 1930

Cells solitary or colonial;; lorica barrel-shaped, constructed of rod-shaped costal strips and with projections; 10-16 longitudinal costae extending anteriorly as projections, 2-6 transverse costae; cell in some species suspended from anterior portion of the lorica; lorica sometimes with simple pedicel; division tectiform; morphologically diverse; marine and brackish-water; worldwide.

Choanoflagellates with obovoid cell about 9 microns long x 4 microns wide; funnel-shaped collar of 40-60 tentacles about 7 microns long. Lorica 90-130 microns high consisting of one chamber 65-110 microns high formed by 9 longitudinal and 2 transverse costae. Longitudinal costae from spines at anterior end of lorica, each spine containes two costal strips. 3 longitudinal costae extend beyond the posterior transverse costa and converge to join with a stalk 22-26 microns long formed by 3 or more costal strips.

Choanoflagellates with a hyaline ribbed lorica; said by some to have a faintly pigmented pale green portion ovoid; 5 microns wide by 8 microns long; single flagellum 15-17 microns long. Enclosed in transparent, slightly flattened, basket-like lorica 16 microns wide by 24 microns long (including spines); lorica invaginated where flagellum emerges, tapering to a point opposite closed end. The lorica usually ornamented with three peripheral ridges transverse to longitudinal axis, and 10 emergent longitudinal ridges that merge at closed end but extend freely a distance of 10 microns to form a fringe of spines beyond open end.

Similar to the typical form of D. multiannulata but with smaller overall dimensions and only 3 distinct transverse costae. Associated with sea ice.

Diaphanoeca is a genus of choanoflagellates belonging to the family Acanthoecidae.

Species:

Diaphanoeca aperta B.S.C.Leadbeater Diaphanoeca cylindrica B.S.C.Leadbeater Diaphanoeca fiordensis (R.F.Scagel & J.R.Stein) R.E.Norris Diaphanoeca grandis Ellis Diaphanoeca multiannulata Buck Diaphanoeca parva W.Ellis Diaphanoeca pedicellata Leadbeater Diaphanoeca sphaerica Thomsen Diaphanoeca undulata Thomsen