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Updated: Jun 20, 2026

Gamete Collection and In Vitro Fertilization of Astyanax mexicanus
Published on: May 25, 2019
Long-term retention of self-fertilization in a fish clade
Andrey Tatarenkov1, Sergio M Q Lima, D Scott Taylor
1Department of Ecology and Evolutionary Biology, University of California, Irvine, CA 92697, USA.
Abstract:
Among vertebrate animals, only the mangrove rivulus (Kryptolebias marmoratus) was known to self-fertilize. Here, we use microsatellite analyses to document a high selfing rate (97%) in a related nominal species, Kryptolebias ocellatus, which likewise is androdioecious (populations consist of males and hermaphrodites). In contrast, we find no evidence of self-fertilization in Kryptolebias caudomarginatus (an androdioecious species closely related to the marmoratus-ocellatus clade) or in Kryptolebias brasiliensis (a dioecious outgroup). These findings indicate that the initiation of self-fertilization predated the origin of the marmoratus-ocellatus clade. From mitochondrial DNA sequences and microsatellite data, we document a substantial genetic distance between Kryptolebias marmoratus and K. ocellatus, implying that the selfing capacity has persisted in these fishes for at least several hundred thousand years.
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