Microanatomy of the male and female reproductive tracts in the long-tailed butterfly ray Gymnura poecilura, an elasmobranch with unusual characteristics

Authors

  • A. C. Henderson,

    Corresponding author
    1. Department of Marine Science & Fisheries, College of Agricultural & Marine Sciences, Sultan Qaboos University, Muscat, Oman
    • Author to whom correspondence should be addressed at present address: The School for Field Studies, Center for Marine Resource Studies, South Caicos, Turks & Caicos Islands. Tel.: +649 332 3379; email: ahenderson@fieldstudies.org

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  • A. J. Reeve,

    1. Department of Marine Science & Fisheries, College of Agricultural & Marine Sciences, Sultan Qaboos University, Muscat, Oman
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  • A. Ambu-Ali

    1. Department of Marine Science & Fisheries, College of Agricultural & Marine Sciences, Sultan Qaboos University, Muscat, Oman
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Abstract

The anatomy of the male and female reproductive systems was investigated in the long-tailed butterfly ray Gymnura poecilura using gross observation and light microscopy. The testes are highly asymmetrical, to the extent that only the left testis is functional and the right testis is completely absent. Both of the male genital ducts are present and symmetrical, although spermatozoa only occur in the left duct. The genital ducts are straight and unconvoluted, with regular incomplete internal partitions throughout. Females do not possess a right ovary, nor do the oviducal glands exhibit distinct club and papillary zones, and the baffle zone lacks baffle plates. In all sections of the gland, the tubules display different secretory activities depending on the proximity to the gland lumen. The gland produces a thin egg membrane that encases each egg individually, while the endometrium is formed into trophonemata.

Ancillary