Sarawak pygmy swellshark explained

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.

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. The species uniquely uses sustained single oviparity producing larger but fewer eggs than others.[1]

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.[2]

Notes and References

  1. News: Shiffman . David . This Mommy Shark Has a Unique Way of Making Babies . 26 October 2020 . . 21 October 2020.
  2. Nakaya . Kazuhiro . White . William T. . Ho . Hsuan-Ching . 2020-07-23 . Discovery of a new mode of oviparous reproduction in sharks and its evolutionary implications . Scientific Reports . en . 10 . 1 . 12280 . 10.1038/s41598-020-68923-1 . 2045-2322 . 7378224 . 32703969.