Sarawak pygmy swellshark

The Sarawak pygmy swellshark (Cephaloscyllium sarawakensis) is a species of catshark, belonging to the family Scyliorhinidae. It is found in the benthic zone near the edge of the Pacific continental shelf, at depths of 118–165 m.^[2]

Sarawak pygmy swellshark
Conservation status
Critically Endangered  (IUCN 3.1)[1]
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Chondrichthyes
Subclass:	Elasmobranchii
Division:	Selachii
Order:	Carcharhiniformes
Family:	Scyliorhinidae
Genus:	Cephaloscyllium
Species:	C. sarawakensis
Binomial name
Cephaloscyllium sarawakensis Ka. Yano, A. Ahmad & Gambang, 2005
Synonyms
Cephaloscyllium circulopullum Ka. Yano, A. Ahmad & Gambang, 2005

Description

The species reaches a maximum size of 40.8 cm length; males mature at 32.5 cm length and females at 35.4–40.8 cm length.^[3] The species uniquely uses sustained single oviparity producing larger but fewer eggs than others.^[4]

Sustained single oviparity

The mode of oviparity in the Sarawak pygmy swellshark has been found to differ considerably from the two previously defined modes of oviparity found in Chondrichthyans. This unique form of oviparity has been described as "sustained single oviparity," a mode of oviparity characterized by the deposition and retention of a single egg case in each oviduct until the two embryos reach a length ranging 16.5–20.1% total length.^[5]