The genital and anal papillae of Compsura heterura (Characidae: Cheirodontinae): morphological structure and possible role in insemination

Abstract

The function of the genital and anal papillae for insemination in Compsura heterura is discussed based on the description of their morphologies at different stages of the life cycle and during copulation and spawning. In males and females both the genital and anal papillae are involved in copulation in C. heterura. A pre-anal organ, anterior to the anus and stretched posteriorly, is present in adult males. The openings of the urinary channel and oviduct are separate in females. During copulation, there is an approximation between the female genital and anal papillae which become temporarily juxtaposed, forming a chamber enclosing the opening of the oviduct, which may also function in sperm capture. During spawning, the lateral edges of the female genital papilla are projected anteriorly, acquiring a tubular shape for oviposition.

Morphology of the urogenital papilla of the male marine teleost Black Rockfish, Sebastes schlegelii (Hilgendorf, 1880), and its role in internal fertilization

“…In this study, both the female and male Black Rockfish had three openings on the outside of their bodies-the anus, reproductive tract, and urethra. This is similar to that in the females of some fishes, including phallostethid fishes (Atherinomorpha) (Parenti, 2014), Compsura heterura (Characidae: Cheirodontinae) (Lezama & Malabarba, 2021), Nile tilapia (Oreochromis niloticus) (Moore & Roberts, 2017), and Astroblepus (Ostariophysi: Siluriformes: Astroblepidae) (Spadella et al, 2012); however, the sperm ducts in the males of these species merge with the urinary duct, and the combined urogenital duct passes through to the tip of the intromittent organ (Parenti, 2014;Spadella et al, 2012). Yellow perch and rainbow trout have two openings-anal and urogenital tracts (Malison et al, 2011;Strange & Kibenge, 2021).…”

“…One possible function of this separation of the reproductive tract and urethra in Black Rockfish is to increase the success of sperm entering a female's reproductive tract, so as not to be mixed with the urine from the opposite direction. Another possibility is that the separate genital opening allows for the formation of a chamber near the gonopore (Lezama & Malabarba, 2021). Black Rockfish generally mate in November, and the young are usually born in April or May of the following year; therefore, females need to store sperm in a chamber along the reproductive tract before fertilization.…”

Reprodução De Peixes De Riacho: Estado Da Arte, Métodos E Perspectivas

“…Muitas informações relevantes e inéditas podem ser obtidas com registro subaquático, por observação direta, fotos ou vídeos ou pela manutenção de indivíduos da espécie alvo em aquário (e.g. Anjos & Anjos, 2006;Lezama & Malabarba, 2021), sob condições controladas.…”

“…Com base nas situações descritas no tópico anterior, recomenda-se buscar padrões no aparecimento de variações de tamanho, cor, morfologia e presença de ganchos em nadadeiras (Characiformes), odontódeos (Siluriformes), tubérculos, morfologia das papilas. A função das papilas anal e genital de Compsura heterura (Characiformes, Characidae) foi discutida por Lezama & Malabarba (2021) com base em sua morfologia em diferentes estágios do ciclo de vida, e durante a cópula e a desova. Espécies de Hollandichthys e Rachoviscus (Characiformes, Characidae) são também inseminadores típicos de riachos (da Mata Atlântica), com modificações aparentemente associadas à transferência de esperma (Bertaco & Malabarba 2013).…”

“…A confirmação de zigoparidade (Fukakusa et al 2020) em C. heterura certamente é um estímulo para investigações semelhantes em outras espécies inseminadoras, assim como o estudo de Lezama & Malabarba (2021), que confirma e elucida a transferência dos espermatozoides na mesma espécie. Para L.R.…”