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Posté le : 23/04/2020 12:44:11
Parthenogenèse confirmée ! " Melanoides tuberculata in the Kuala Lumpur area of Malaysia were found to be entirely female, reproducing parthenogenetically. The reproductive system is extremely simple in structure and histology, lacking all the glandular developments common in most mesogastropods. Eggs pass into a cephalic brood‐pouch where they develop to juveniles of 5–6 shell whorls before emergence. Numbers of developing young in the brood‐pouches increased with shell height of the parents except for a decline in the few very largest snails. The highest brood‐pouch count was 265, but average counts were much lower. "
Reproduction in the Malayan freshwater cerithiacean gastropod Melanoides tuberculata, 1974
" Ping Long M. tuberculata were exclusively female, as is typical of most populations of this species. Animals > 3.0 mm shell width (90–120 days old) had eggs and developing larvae in the brood pouch, and fully–developed larvae were recorded from brood pouches throughout the study although release of hatchlings was distinctly seasonal"
The life cycle, population dynamics and productivity of Melanoides tuberculata (Muller, 1774) (Gastropoda: Prosobranchia: Thiaridae) in Hong Kong, 1986
Il y a aussi une forme de reproduction sexuée, mais elle est plus minoritaire. "Although these snails are described as parthenogenetic, we find that some populations in Israel contain 20–33% of males producing motile spermia, while other populations consist only of females. In all populations the offspring are incubated in brood-pouches. The length of incubation is correlated to population density."
Biology and reproduction of the freshwater snail Melanoides tubercolata (Gastropoda: Prosobranchia) in Israël, 1983
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