Neotrops poguazu Grismado and Ramírez, 2013

SPERM TRANSFER FORM (fig. 11): Ovalshaped synspermia (,10 Mm), comprising four sperm (fig. 11A). In the periphery of the sperm conjugate, numerous membranes are visible (fig. 11B, arrow). Synspermia surrounded by a thin (, 80 nm) secretion sheath (fig. 11B, C); cytoplasm electron dense within sperm conjugates of the ejaculatory duct (fig. 11D), some mitochondria present.

SPERMATOZOA (fig. 11): Acrosomal complex: AV conical with wide subacrosomal space (figs. 11A, C), proximally sunken into the anterior pole of prcN (fig. 11C). AF originates from subacrosomal space, extends into NC, but clearly ends before axonemal base. Nucleus: prcN deeply indented at its anterior pole (bowl shaped), irregularly shaped with irregularly condensed chromatin (fig. 11A, B). peN short, flattened, (fig. 11D). NC peripheral (fig. 11 A–C). Axoneme: proximal centriole longer than distal centriole, 9+3 microtubular pattern.

Note on Spermiogenesis (fig. 12): All stages of spermiogenesis present in the testis. Spermatids of the same developmental stage arranged in cysts. Early spermatids characterized by a large, oval nucleus surrounded by a manchette of microtubules and small AV (fig. 12A inset) that is separated from the nucleus by a distinct electron-dense border (fig. 12A). The AF originates from the subacrosomal space (12C). The chromatin begins condensing in the center of the nucleus and appears fibrillar (fig. 12A, B). The small implantation fossa is irregularly shaped in early spermatids (fig. 12B, B inset). There is always a small amount of electron-dense, granular material associated with the proximal centriole (fig. 12D). A collar of electron-dense, platelike secretions surrounds the base of the Ax (fig. 12E). At the end of spermiogenesis late spermatids that remained connected via cellular bridges start to fuse, finally resulting in synspermia.