Reproductive biology of Lychnorhiza lucerna (Cnidaria: Scyphozoa: Rhizostomeae): Individual traits related to sexual reproduction

We studied individual traits related with sexual reproduction of Lychnorhiza lucerna and review how sexual maturation has been studied for scyphomedusae, focusing on the particular case of non-brooding species. L. lucerna is a gonochoric species and sexual dimorphism was found in the colour of the g...

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Bibliographic Details
Authors: Schiariti, Agustin, Christiansen, Enesto, Morandini, Andre Carrara, da Silveira, Fabio Lang, Giberto, Diego Agustin, Mianzan, Hermes Walter
Format: article
Status:Published version
Publication Date:2012
Country:Argentina
Institution:Consejo Nacional de Investigaciones Científicas y Técnicas
Repository:CONICET Digital (CONICET)
Language:English
OAI Identifier:oai:ri.conicet.gov.ar:11336/107804
Online Access:http://hdl.handle.net/11336/107804
Access Level:Open access
Keyword:NON-BROODER SPECIES
OOGENESIS
SEXUAL MATURITY
SPERMATOGENESIS
https://purl.org/becyt/ford/1.6
https://purl.org/becyt/ford/1
Description
Summary:We studied individual traits related with sexual reproduction of Lychnorhiza lucerna and review how sexual maturation has been studied for scyphomedusae, focusing on the particular case of non-brooding species. L. lucerna is a gonochoric species and sexual dimorphism was found in the colour of the gonads. There were no brooding structures or any other distinguishable feature that enable macroscopic determination of sex. Gametogenesis in L. lucerna resembled the descriptions available for other rhizostomes and semaeostomes. Both processes are asynchronous since gametes at all stages of development occurred simultaneously. Oocytes arose from the gastrodermis and maintained contact with it via trophocytes throughout vitellogenesis. Spermatogenesis occurred within the spermatic follicles arising from nested primary spermatogonia in the mesoglea. Population features of sexual reproduction are defined by characterizing and quantifying individuals at different stages of sexual maturity. Regarding sexual maturation in Scyphozoa, sexually mature medusae can be detected by i) the presence of fully-developed gametes in the gonads indicating near future spawning, or ii) by the presence of spent spermatic follicles as evidence of ongoing or recent spawning events. Whereas the former allows getting a more detailed study of sexual reproduction patterns of any species, the later constitutes an option for non-brooders equivalent to the search of fertilized eggs or planulae for brooder species, as exemplified in this work.