Hermaphroditism in a violet snail, Janthina pallida (Gastropoda, Caenogastropoda): a contribution
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The first data are provided on the gonad development of the violet snail Janthina pallida Thompson, 1840. Histological investigations were carried out on twenty-two specimens cast ashore alive in the Straits of Messina (central Mediterranean). All specimens had an ovotestis with distinct male and female gonads. In large individuals, germinative cells in different stages of spermatogenesis and flagellate spermatozoa were detected, together with oocytes in different stages of oogenesis and mature oocytes; in small specimens only immature male and female gonads were observed. No specimens of intermediate size were found. Simultaneous rather than size-related hermaphroditism in J. pallida contrasts with the current view of protandric hermaphroditism as a common trait in Janthina genus, instead suggesting a changing reproductive pattern, driven by population density and food availability.
KeywordsJanthina pallida Reproduction Spermatozeugma Hermaphroditism
We wish to thank the reviewer Alan Beu for the precious suggestions and language review, and Walter Renda for figures graphic composition.
This study was supported by the Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Italy (Research Programm “ORME09Y JE”).
Compliance with ethical standards
Conflict of interest
All authors declare that they have no conflict of interest.
In this article all applicable international, national, and/or institutional guidelines for the care and use of animals were followed.
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