Twins! Microsatellite analysis of two embryos within one egg case in oviparous elasmobranchs

Autoři: Samantha A. Hook aff001;  Syafiq M. Musa aff001;  Daniel M. Ripley aff001;  Jean-Denis Hibbitt aff004;  Bianka Grunow aff005;  Timo Moritz aff006;  Holly A. Shiels aff001
Působiště autorů: Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom aff001;  School of Earth and Environmental Sciences, University of Manchester, Manchester, United Kingdom aff002;  School of Environmental and Natural Resource Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Selangor, Malaysia aff003;  SEA LIFE Programmes and Engagement, SEA LIFE Weymouth, Weymouth, United Kingdom aff004;  Leibniz-Institute of Farm Animal Biology, Dummerstorf, Germany aff005;  Deutsches Meeresmuseum, Stralsund, Germany aff006;  Institut für Zoologie und Evolutionsforschung, Friedrich-Schiller-Universität Jena, Germany aff007
Vyšlo v časopise: PLoS ONE 14(12)
Kategorie: Research Article
doi: 10.1371/journal.pone.0224397


Elasmobranchs display various reproductive modes, which have been key to their evolutionary success. In recent decades there has been a rise in the number of reported cases of foetal abnormalities including fertilised, double-embryos held within one egg capsule, hereafter referred to as twins. Previously, the occurrences of twin egg cases have been reported in two batoid and one shark species. We report the first cases of twins in three species of oviparous elasmobranchs: the undulate ray (Raja undulata), the nursehound (Scyliorhinus stellaris), and the small-spotted catshark (Scyliorhinus canicula). We investigated the genetic relationships between the twins in S. stellaris, and S. canicula using microsatellite markers. Whilst the S. stellaris twins displayed the same genotypes, we found that the S. canicula twin individuals arose through heteropaternal superfecundation. This is the first reported incidence of such a paternity in elasmobranchs. The relationship between environmental change and reproductive strategy in elasmobranchs is unclear and further research is needed to determine its effect on the prevalence and mechanisms of formation of elasmobranch twins.

Klíčová slova:

Elasmobranchii – Embryos – Microsatellite loci – Sharks – Twins – Yolk sac – Skates and rays – Clutches


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2019 Číslo 12