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The eggs are enclosed in a cocoon, which in aquatic species is usually attached to an underwater surface; members of one family, Glossiphoniidae, exhibit parental care, and the eggs being brooded by the parent. In terrestrial species, the cocoon is often concealed under a log, in a crevice or buried in damp soil.
Leech embryogenesis is the process by which the embryo of the leech forms and develops. The embryonic development of the larva occurs as a series of stages. During stage 1, the first cleavage occurs, which gives rise to an AB and a CD blastomere, and is in the interphase of this cell division when a yolk-free cytoplasm called teloplasm is formed. [1]
Male genitalia of Lepidoptera. The main component of the male reproductive system is the testicle, suspended in the body cavity by tracheae and the fat body.The more primitive apterygote insects have a single testis, and in some lepidopterans the two maturing testes are secondarily fused into one structure during the later stages of larval development, although the ducts leading from them ...
The clitellum is part of the reproductive system of clitellates, a subgroup of annelids which contains oligochaetes (earthworms) and hirudineans (leeches). The clitellum is a thick, saddle-like ring found in the epidermis (skin) of the worm, usually with a light-colored pigment. To form a cocoon for its eggs, the clitellum secretes a viscous ...
Fertilization and development of earthworm eggs takes place in the cocoon. Leeches' eggs are fertilized in the ovaries, and then transferred to the cocoon. In all clitellates the cocoon also either produces yolk when the eggs are fertilized or nutrients while they are developing. All clitellates hatch as miniature adults rather than larvae. [46]
Leeches are hermaphrodites, and mating may take place on or off the fish host, but in either case, the cocoon, usually containing a single egg, is deposited elsewhere, usually stuck to a stone or piece of vegetation, or even to the carapace of a crustacean. When the egg hatches, the juvenile leech has about a week to find a suitable fish host ...
Glossiphoniid leeches exhibit remarkable parental care, the most highly developed one among the known annelids. They produce a membranous bag to hold the eggs, which is carried on the underside. The young attach to the parent's belly after hatching and are thus ferried to their first meal. [6] Certain Glossiphoniidae parasitize amphibian species.
Macrobdella decora, also known as the North American medicinal leech, is a species of freshwater leech found in much of eastern North America in freshwater habitats, although there is one disjunct population in northern Mexico. M. decora is a parasite of vertebrates, including humans, and an aquatic predator of eggs, larvae, and other ...