White-edge freshwater whipray | |
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Scientific classification | |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Chondrichthyes |
Subclass: | Elasmobranchii |
Order: | Myliobatiformes |
Family: | Dasyatidae |
Genus: | Himantura |
Species: | H. signifer |
Binomial name | |
Himantura signifer Compagno & T. R. Roberts, 1982 |
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Range of the white-edge freshwater whipray |
The white-edge freshwater whipray (Himantura signifer) is an extremely rare species of stingray in the family Dasyatidae, native to four river systems in Southeast Asia. Measuring up to 60 cm (24 in) across, this ray has an oval pectoral fin disc and a very long, whip-like tail without fin folds. It can be identified by the presence of a sharply delineated white band running around the margin of its otherwise brown disc, as well as by its white tail and a band of dermal denticles along the middle of its back. This species feeds on benthic invertebrates and is aplacental viviparous. Its two long tail spines are potentially dangerous to humans. The International Union for Conservation of Nature (IUCN) has assessed the white-edge freshwater whipray as Endangered, as it is under heavy pressure from fishing and habitat loss, degradation, and fragmentation.
The white-edge freshwater whipray was described by Leonard Compagno and Tyson Roberts in a 1982 issue of Environmental Biology of Fishes, with the specific epithet signifer (Latin for "sign-bearing") in reference to its distinctive coloration. The type specimen is an immature female 29 cm (11 in) across, collected from the mouth of the Sungai Ketungau off the Kapuas River in West Kalimantan, Indonesia. Other common names for this species include freshwater stingray, pale whipray, and white-rimmed stingray. Within its genus, the white-edge freshwater whipway most closely resembles H. kittipongi, described in 2005. A 1999 phylogenetic analysis, based on sequences, found that it is closely related to H. gerrardi and H. imbricata, which form a sister species pair.