Lepore, E.; Sciscioli, M.; Liaci, L. S.; Santarelli, G.; Gaino, E. (2000). Sexual reproduction of Cinachyra tarentina (Porifera, Demospongiae). Italian Journal of Zoology. 67(2): 153-158.
The sexual reproductive cycle of the Tetractinomorpha Spirophorida Cinachyra tarentina was studied mainly using light microscopy on samples collected in South Italy over a 2-year period. Some aspects of the egg morphology were observed using transmission electron microscopy. Each year, young oocytes in pre-vitellogenesis appeared in May and coexisted with growing oocytes. Yolk-filled eggs were present in June and July. Oogenesis preceded spermatogenesis which occurred only in June. Cinachyra tarentina is an oviparous species having small eggs ranging from 40 to 50 pm in diameter which are scattered in the mesohyl and have a nucleolated nucleus surrounded by dictyosomes of the Golgi apparatus. Growing oocytes and yolk-filled eggs have an irregular surface because of the presence of numerous pseudopodia which protrude into the mesohyl. Even though apparently gonochoric individuals were mostly observed, the rare specimens with sperm clusters and young oocytes proved the occurrence of successive hermaphroditism as an underlying mechanism. Some aspects of the reproductive biology of C. tarentina are compared with that of other Tetractinomorpha.
