Myozonaria fissipara

Description:

Photomicrographs of Myozonaria fissipara nov. sp. (Myozonariinae) (?C, MTP LS 651, paratype and hologenophore voucher; ?G, MTP LS 678, holotype and hologenophore voucher) (see Fig. 14 for taxonomic drawings). (A) The overall asexual habitus with two zooids in the process of fissioning at a clear fission plane (arrow head), both with clearly visible muscle rings (arrows) and pharynges. (B) Detail of the muscle ring of the anterior zooid showing circular muscle fibers. (C) Detail of the fission plane, clearly showing that the gut is still connected between the zooids (arrow). (D) The overall habitus of a sexual specimen with clearly visible muscle ring (arrow) and reproductive structures, including a mature oocyte (o), penis stylet (ps), accessory stylet (as), seminal vesicle (sv), and sperm tubes (st); note that the gut extends posteriorly (arrow head). (E) Bursal organ (bo) with attached sperm tube (st) filled with sperm (arrow). (F) Sperm cells released from the ruptured seminal vesicle; (G) accessory stylet (as) and penis stylet (ps). Note that panels ?G are from a highly squeezed preparation used to make the deposited permanent lactophenol preparation. Scale bars: 50 um, except A, D 100 um.