Multiple births by a captive swellshark Cephaloscyllium ventriosum via facultative parthenogenesis

Abstract

Using a novel set of 12 microsatellites, a captive, adult female swellshark Cephaloscyllium ventriosum that produced five pups via parthenogenesis is described; naturally occurring parthenogenesis has been observed in every vertebrate class with the exception of mammals. As demonstrated in this study, a captive environment is ideal for long-term monitoring of animals under controlled conditions, and easily allows the detection of particular facets of their biology.

Convergent recombination cessation between mating-type genes and centromeres in selfing anther-smut fungi

“…Automixis with central fusion can thus maintain long-term heterozygosity, which can lead to sheltering deleterious alleles or may be beneficial in cases of advantageous overdominance (i.e., heterozygote advantage) (Engelstädter 2017). Automixis and its genetic and evolutionary consequences are poorly studied despite being relatively frequent (Mogie 1986) across a variety of taxa such as in fungi (Hood and Antonovics 2000;Zakharov 2005;Menkis et al 2008;Grognet et al 2014), plants (Asker 1980;Walker 1985;Antonius and Nybom 1995;Cruden and Lloyd 1995;Schön et al 2009), reptiles (Watts et al 2006;Booth et al 2011;Booth and Schuett 2015), fishes (Chapman et al 2007;Dudgeon et al 2017;Feldheim et al 2017), birds (Schut et al 2008), crustaceans (Nougué et al 2015), nematodes (Van der Beek et al 1998), and insects (Suomalainen et al 1976;Normark 2003;Oldroyd et al 2008).…”

The Sandy Zebra Shark: A New Color Morph of the Zebra Shark Stegostoma tigrinum, with a Redescription of the Species and a Revision of Its Nomenclature

“…Kottelat (2013) mentions that Stegostoma tigrinum Forster, 1781 should have priority under code article 23.9.1, which states that if a name has been used after 1899, it cannot be suppressed. Stegostoma tigrinum has been used at least 21 times from 1903 (Kishinouye and Zashi, 1903) to 2016 (Feldheim et al, 2016). Nevertheless, Stegostoma fasciatum Hermann, 1783 has been accepted as the scientific name for the Zebra Shark by Compagno (1984) and most authors since, even though this description is based on Seba (1759) and not on an actual specimen.…”

Reproductive biology of the swell shark Cephaloscyllium ventriosum (Carcharhiniformes: Scyliorhinidae)

“…This species is oviparous and stores sperm in the oviducal gland (Grover, 1970). It has recently been documented that it can generate new organisms through parthenogenesis (Feldheim et al ., 2016), therefore histological studies are relevant to identify cellular characteristics that may provide useful insights into C. ventriosum 's reproductive strategies.…”