Zoological Studies

Vol. 61, 2022

(update: 2022.2.23)

Genetic Structure of the Mangrove Killifish Kryptolebias hermaphroditus Costa, 2011 (Cyprinodontiformes: Aplocheiloidei) Supports A Wide Connection among Its Populations

Pedro F. Amorim1,*, Axel Makay Katz2, Felipe Polivanov Ottoni3, and Pedro Henrique Negreiros de Bragança4
doi:10.6620/ZS.2022.61-04

1Laboratory of Systematics and Evolution of Teleost Fishes, Genetic Graduation Program, Institute of Biology, Federal University of Rio de Janeiro, CEP 21941-902, Rio de Janeiro, Brazil. * Correspondence: E-mail: pedro_f_a@hotmail.com (Amorim)
2Laboratory of Systematics and Evolution of Teleost Fishes, Biodiversity and Evolutionary Biology Graduation Program, Institute of Biology, Federal University of Rio de Janeiro, CEP 21941-902, Rio de Janeiro, Brazil. E-mail: axelmk@gmail.com (Katz)
3Laboratory of Systematics and Ecology of Aquatic Organisms, Center for Agricultural and Environmental Sciences, Federal University of Maranhão, CEP 65500-000, BR-222, KM 04, Boa Vista, Chapadinha, MA, Brasil. E-mail: fpottoni@gmail.com (Ottoni)
4South African Institute for Aquatic Biodiversity, Private Bag 1015, Grahamstown, Eastern Cape, South Africa. E-mail: pedrobra88@gmail.com (Bragança)

Received 6 June 2021 / Accepted 19 December 2021
Communicated by Yasuyuki Hashiguchi

The Kryptolebias marmoratus species group is composed of the only three vertebrate species that lack females. These species present only males and simultaneously hermaphroditic individuals; that are able to reproduce by allogamy, with males, or by autogamy, performing  self-fertilization and generating clones of themselves. The proportion of males is variable among those species and even among their populations. Kryptolebias hermaphroditus has the smallest proportion of males. Indeed, no males have been recorded in most known populations. This is a mainly autogamous species, with small populations having a disjunct distribution along the eastern and northern coast of Brazil. Species presenting such adaptations would be expected to have an elevated rate of genetic population structure, reflecting any barriers that obstruct gene flow between populations. Partial sequences of the mitochondrial cytochrome c oxidase I (COI) gene from 335 individuals were sampled to perform a population analysis. Only a single haplotype of COI, widely distributed throughout all the sampled populations, was recovered for K. hermaphroditus. Here we hypothesize that the high degree of communication within populations is probably the main biological
feature leading to this pattern.

Key words: DNA-barcoding, Gene flow, Mitochondrial DNA, Neotropical, Self-fertilizing hermaphrodites, South America.

Citation: Amorim PF, Katz AM, Ottoni FP, Bragança PHN. 2022. Genetic structure of the mangrove killifish Kryptolebias hermaphroditus Costa, 2011 (Cyprinodontiformes: Aplocheiloidei) supports a wide connection among its populations. Zool Stud 61:4. doi:10.6620/ZS.2022.61-04.

Supplementary materials: Table S1