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, Arrows indicate follicle cells

, Tedania ignis: Spermatocytes and spermatids. (a) Spermatogonia (sp) and primary 484 spermatocytes (sc1) in a spermatic cyst(mes -mesohyl). (b) Primary spermatocyte with a large 485 nucleus (n) in prophase I (arrows indicate synaptonemal complex) clear cytoplasm (cy) and, vol.3

, spermatids (spd) 487 and spermatozoa (spz). (d) Secondary spermatocytes connected through cytoplasmic bridges 488 (cb) (mi -mitochondria; n -nucleus). (e) Secondary spermatocyte in a late stage of transition 489 towards spermatid, with compacting heterochromatin (hc) in the nucleus (n) (fl -flagellum; mi 490 -mitochondria). (f) Mid stage spermatid, Golgi apparatus (ga). (c) Spermatic cyst withsecondary spermatocytes (sp2)

, (g) Spermatid in a late stage, with 492 stretched out nucleus (n) in the apical portion of the elongated cell.The base of the flagellum (fl) 493 appears in the cytoplasm. (h) Basal portion of the spermatid (neck) showing the flagellum (fl) 494 emerging from the cytoplasm, several mitochondria (mi)and clear vesicles (cv). (i) Tip of a late 495

, Iophon proximum: Spermatic cysts, spermatogonia, and primary spermatocytes

, Spermatic cysts (sc) at different maturation stages in the choanosome. (b) Detail of a spermatic 499 cyst (sc),(fc -follicle cells; mes -mesohyl). (c) Detail of a follicle cell with membranous 500 protuberances (mb). (d) Spermatogonia with a large nucleus

, Primary spermatocyte showing basal body and accesory centriole (ac) of the flagellum (fl).(f)

, Detail of the long basal body (bb) close to the Golgi apparatus (ga) and the accessory centriole 503 (ac). (g) Primary spermatocyte with nucleus (n) in prophase I (arrows indicate synaptonemal 504 complexes). (h) Secondary spermatocyte with a large nucleus (n) and compacting chromatin

, Mitochondria (mi) are abundant in all stages

, Iophon proximum: Secondary spermatocytes and spermatids of I. proximum. (a), vol.5

, Secondary spermatocyte (spc2) soon after nuclear division. (b) Detail of a secondary 509 spermatocyte with a large nucleus. (c) Two secondary spermatocytes united by cytoplasmic 510 bridges (cb). (d) Spermatids with compacted and elongated nucleus and cytoplasm being shed

, Several mitochondria (mi) are located in the putative neck of the sperm cell and the flagellum 512 (fl) is emerging from a deep pit (arrows) in the cytoplasm. (e) Detail of the neck of the 513 spermatids with the flagellum insertion in the invagination of the cell (arrows). (f) Late 514 spermatid with stretched nucleus and residual cytoplasm (rc) being shed alongside the cell.(cy -515 cytoplasm; mi -mitochondria