Honeycomb whipray
The honeycomb whipray is a species of stingray in the family Dasyatidae, found widely in the shallow coastal waters of the Indo-Pacific from India to the Malay Archipelago. This large species grows to across and has a diamond-shaped disc with rounded corners and a projecting, pointed snout. Its tail is long and whip-like, without fin folds. Adults have a striking dorsal color pattern consisting of large, dark brown rings and reticulations delineated by thin yellow lines, while juveniles have a pattern of large dark spots. This ray can also be distinguished from its similar relatives by an enlarged, pearl-like dermal denticle at the center of the back, which is followed by a few thorns. The International Union for Conservation of Nature has assessed the honeycomb whipray as endangered, as it faces heavy fishing pressure and habitat degradation across much of its range.
Taxonomy
Dutch ichthyologist Pieter Bleeker first referenced the honeycomb whipray as Trygon undulata, in an 1850 list of Javanese fishes. Two years later, he formally described the species in the scientific journal Verhandelingen van het Bataviaasch Genootschap van Kunsten en Wetenschappen, based on three specimens caught off Jakarta and Semarang. Later authors assigned it to the genus Himantura. Other common names for this ray include Bleeker's variegate ray and ocellate whipray.The reticulate whipray, the leopard whipray, the fine-spotted leopard whipray, and the Australian whipray are closely related to the honeycomb whipray. The five species are very similar in size, shape, and coloration, which has resulted in a great deal of confusion: H. undulata, H. leoparda and H. tutul have often been misidentified as H. uarnak, while many references to "H. undulata" are in fact of H. leoparda, with the synonym H. fava used instead for the real H. undulata.
Description
The honeycomb whipray has a diamond-shaped, rather thin pectoral fin disc slightly wider than long, with broadly rounded outer corners and concave leading margins converging on a pointed, protruding snout. The eyes are small and immediately followed by much larger spiracles. There is a skirt-shaped flap of skin with a finely fringed posterior margin between the long, narrow nostrils. The mouth is strongly bow-shaped, with shallow furrows at the corners, and contains a pair of papillae on the floor. The teeth are small and have a low, transverse ridge on the crown. The pelvic fins are small and roughly triangular.The tail is thin and whip-like, measuring about twice as long as the disc, and lacks fin folds. Usually a single serrated, stinging spine is placed on the dorsal surface, relatively close to the tail base. Adults have a broad band of small, flattened dermal denticles running centrally from before the eyes, over the back, onto the tail. At the center of the disc, there is an enlarged, round "pearl" denticle trailed by 2-3 smaller thorns along the midline; there are no enlarged denticles on the base of the tail. Newborns have large, well-spaced dark spots covering the disc. With age, the dorsal coloration becomes a honeycomb-like pattern of large, nearly black rings and reticulations, that are separated from each other by thin yellow lines. The tail is covered by alternating dark and light bands or other markings past the sting. The underside is white. This species has been reported to a disc width of.