Indonesian angelshark
| Indonesian angelshark | |
|---|---|
Scientific classification 
| |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Chondrichthyes |
| Subclass: | Elasmobranchii |
| Subdivision: | Selachimorpha |
| Order: | Squatiniformes |
| Family: | Squatinidae |
| Genus: | Squatina |
| Species: | S. legnota
|
| Binomial name | |
| Squatina legnota Last & W. T. White, 2008
| |
| |
| Range of the Indonesian angelshark | |
The Indonesian angelshark (Squatina legnota) is a rare
Critically Endangered
due to significant fishing pressure.
Taxonomy and phylogeny
The Indonesian angelshark was described by
Cilacap landing site in central Java, was designated the holotype. The specific epithet comes from the Greek legnotos ("having a colored border"), in reference to the dark leading margins of the pectoral fins.[2]
Björn Stelbrink and colleagues' 2010
sister species of the Indonesian angelshark is the Taiwan angelshark (S. formosa); the two were the closest genetically of all the species examined. The pair additionally formed a clade with the Japanese angelshark (S. japonica) and the ocellated angelshark (S. tergocellatoides), both also Asian species.[3]
Distribution and habitat
The known specimens of the Indonesian angelshark have come from fish landing sites at Palabuhanratu in
continental slope.[1]
Description
The largest known Indonesian angelshark specimen measured 1.34 m (4.4 ft) long. As in all angel sharks, it has a flattened body with greatly enlarged
pectoral and pelvic fins. The broad, flattened head has a very short, blunt snout and small, widely spaced eyes placed somewhat on top. The eyes are followed by much larger, crescent-shaped spiracles. The nostrils are large and preceded by well-developed flaps of skin that reach the mouth; each flap bears two prominent barbels, which are smooth rather than fringed. The capacious, gently curved mouth is placed at the front of the head. There are long, deep furrows extending from the mouth corners onto and away from the lower jaw. The teeth number around 18 rows in both jaws; each is small and dagger-like, with a single sharp cusp. The five pairs of gill slits are long and placed on the sides of the head.[2]
The pectoral fins are angular, with the anterior lobes of their bases free from the head, and their outer tips forming an angle of slightly under 120°. The tips of the pelvic fins are rounded; males have thick
dermal denticles. This species is grayish brown above, darkening around the eyes and on the snout and becoming translucent at the trailing fin margins. There are blackish saddle markings below the dorsal fin bases, and sometimes also large, dark blotches and "eyespots" scattered over the dorsal surface. The underside is almost completely white, with a black leading margin on the pectoral fins.[2]
Biology and ecology
Little is known of the Indonesian angelshark's natural history. It is presumably
aplacental viviparous like other members of its family. The smallest male specimen, an adult, measured 1.25 m (4.1 ft) long.[1]
Human interactions
The Indonesian angelshark is rarely
IUCN.[1]
References
- ^ doi:10.2305/IUCN.UK.2020-3.RLTS.T161638A113148785.en. Retrieved 19 November 2021.)
{{cite journal}}: CS1 maint: multiple names: authors list (link - ^ .
- PMID 19647086.