Clinus

Abstract: The study follows the embryogenesis of 16 species of viviparous clinid fishes (Clinidae, Teleostei), from the Cape south coast of South Africa and from Australia, with comparative remarks on the development of juveniles in oviparous species. The sperm intromitted into the female duct fertilise the eggs within the follicles. The embryos then develop in individual follicles, nourished by nutrients derived from the mother, until they are mature for release. During the reproductive season in the South African genera Clinus and Muraenoclinus, the female's ovaries harbour eggs and embryos at various stages of development, whereas in species of the Australian genera Heteroclinus and Cristiceps, most embryos in each ovary are at an approximately equal stage of development. The ovaries of the studied species fall into two groups: species of Heteroclinus and Cristiceps that produce numerous small eggs, and species of Clinus and Blennophis that produce fewer, larger eggs. As a consequence, Heteroclinus spp. and Cris...

Abstract: The anatomy and histology of the ovaries of C. superciliosus and C. dorsalis are descriptionbed. The ovaries are extensively modified as trophic organs since embryos of both species develop intrafollicularly and are dependent on maternal nutrient secretions during development. The follicular epithelia of the two species are modified to perform a secretory function and follicular cells are hypertrophied in areas producing embryotrophe. In nonhypertrophied areas the follicular cells remain thin to bring about close contact between the embryos and the maternal vascular system underlying the epithelium. In C. superciliosus embryonic epidermal macroridges are closely aligned to areas of follicular hypertrophy thus forming a pseudoplacenta. A similar arrangement is not found in C. dorsalis.