Rhinoptera javanica

Class: Chondrichthyes
Order: Myliobatiformes
Family: Myliobatidae

Distribution and habitat

  • Found in the Indo- Pacific off China, India, Indonesia, Iran, Japan, Madagascar, Malaysia, Mozambique, Pakistan, the Philippines, Seychelles, Somalia, South Africa, Sri Lanka, Taiwan, Tanzania, Thailand, Vietnam and possibly Australia.
  • Its natural habitats are open seas, estuaries, and near coral reefs, over sand and mud bottoms.
  • Occurs in inshore depths to 30 m.

About the fish

  • It is a large cartilaginous inshore batoid ray with double-lobed snout and indented forehead.
  • Its upper side is brown and underside white.
  • Maximum Size: 150 cm (Disc Width); Weight – 4.5 kg
  • Jaws usually have 7 rows of plate-like teeth.
  • It has rounded pelvic fins and a very small dorsal fin but lacks a caudal fin all together.
  • It possesses stinging spines, which can be found behind the dorsal fin, and a slender whip-like tail.
  • Males court by nipping the female’s dorsum, mating pair orient in venter to venter position, and male inserts claspers.
  • The female is positioned on top of the male, and mating lasts about 30 seconds – 1 minute.
  • Exhibit ovoviparity, with embryos feeding initially on yolk, then receiving additional nourishment from the mother by indirect absorption of uterine fluid enriched with mucus, fat or protein through specialized structures.
  • This species most likely has 1 to 2 young per litter due to the large size at birth.
  • Size at birth: one late term embryo was 63 cm DW
  • IUCN has listed this species as vulnerable.
  • The small litter size, tendency to form large schools, its inshore and estuarine habitat and hence availability to a wide variety of inshore fishing gear, its marketability warrants a global Vulnerable assessment.