Rajella purpuriventralis

Batoids of moderate to very large size, disc width from 30 cm to more than 2 m. Body strongly depressed, with head, trunk, and broadly exp anded pectoral fins forming rhomboid or oval- shaped disc. Disc not more than 1.3 times as broad as long. Tail distinctly demarcated from disc. Pectoral fins continuous along sides of head, not forming subrostral lobes or cephalic fins. Snout obtuse, rounded, or more or less pointed. Eyes and spiracles on top of head. Floor of mouth with fleshy papillae. Sm all teeth in many series forming b ands along jaws. Nasal curtains well developed and continuous across narrow isthmus in front of mouth and deeply fringed. No dorsal fins or caudal fin. Tail very slender, taper- ing, much longer than disc, and with 1 or more saw-edged, long, poisonous spines on medial half of length. Some species with longitudinal tail folds (fin-folds) on upper and/or lower surface. Skin on dorsal side naked or armed with tubercles or prickles. Colour: dorsal surface usu ally grey to dark brown, sometimes with darker or paler markings; ventral surface gener ally whitish. pectoral fins continuous along sides of head slender tail no dorsal or caudal fin poisonous spine

Body shape: other.

Widely distri buted from New Jer- sey to Florida, throughout the Gulf of Mexico, Ba- hamas, and the Greater and Lesser Antilles, and bordering the nor thern coast of South America to sou theastern Brazil. Note: Records of Dasyatis pastinaca from Uru- guay are probably of this species or Dasyatis say.

Whiptail stingrays occur primarily in tropical to warm-temperate waters worldwide; they are usu ally found in sh allow coastal waters, lagoons, estuaries, and occasion ally fresh waters, but a few species may occur in deeper waters (beyond 100 m). In tropical regions some species are restricted to fresh waters. All but 1 species are benthic and often remain, for extended periods of time, parti ally buried in soft bottom substrates. The exception (Pteroplatytrygon violacea) is epipelagic in open oceans and along continental and insular shelf margins. All species are viviparous without placentas, young remain in oviducts of female until they are fully formed. Eight species in 3 genera occur in the area. Some stingrays are reportedly very abundant in certain localities and are regularly seen in local markets (e.g. in Venezuela). The flesh (thicker part of disc) is well esteemed as food; o ther parts are used in preparation of gelatin and liver oil. Some species are important for ecoturism (Dasyatis say and Dasyatis ameri cana of Gr and Cayman Isl and). disc more broad Similar families occurring in the area than long Gymnuridae: disc more than 1.5 times as broad as long; no papillae on floor of mouth; nasal curtains smooth-edged. Gymnuridae Myliobatidae, Rhinopteridae, Mobulidae: head distinctly demarcated from body, anterior portions of pectorals forming separate lobes or fins; eyes and spiracles on sides of head. Urotrygonidae: well-developed caudal fin, supported by cartilaginous radials. Other families of batoids: lack characteristic tail spine(s); tail stout to moderately slender; 1 or 2 dorsal fins and rudimentary caudal fin. head distinctly demarcated from body well-developed caudal fin Myliobatidae Urotrygonidae Key to the species of Dasyatidae occurring in area 1a. Anterior margin of disc evenly convex to nearly straight (Fig. 1a) . . . . . . . . . . . . . . .(cid:1) 2 1b. Anterior margin of disc subangular, with tip of snout forming apex of angle (Fig. 1b) . . . . . . .(cid:1) 3 anterior margin of disc evenly anterior margin of convex to nearly disc subangular straight a) b) Fig. 1 dorsal view of anterior margin of disc 2a. Dorsal surface uni formly c overed with numerous sm all tubercles, and with enlarged tuber- cles over scapular region; ventral surface of disc creamy white to yellowish, often with vari- ously coloured blotches and dusky margin; ventral surface of tail with very low and indistinct keel . . . . . . . . . . . . . . . . . . . . . . . . . . . . Himantura schmardae 2b. Dorsal surface of disc mostly naked, no enlarged tubercles over scapular region; ventral surface of disc uni formly brown to black; ventral surface of tail with well-developed fin-fold or flap, usu ally t aller than tail . . . . . . . . . . . . . . . . . . . . . Pteroplatytrygon violacea 3a. Pelvic fins greatly exp anded later ally, more than twice as wide as long, and with narrowly pointed outer corners; preorbital length more than 4 times distance between eyes (Fig. 2a) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Dasyatis geijskesi 3b. Pelvic fins not greatly exp anded later ally, only about as wide as long, and with broadly rounded outer corners; preorbital length between 1 and 2 times distance between eyes (Fig. 2b) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (cid:1) 4 pelvic fins later ally exp anded pelvic fins not greatly exp anded a) dorsal (upper figure) b) ventral view and ventral (lower figure) views Fig. 2 pelvic fins 564 Batoid Fishes 4a. Outer corners of disc broadly and evenly rounded (Fig. 3a) . . . . . . . . . . . . . . . . .(cid:1) 5 4b. Outer corners of disc narrowly rounded or subangular (Fig. 3b). . . . . . . . . . . . . . . .(cid:1) 6 outer corners of disc outer corners of rounded disc subangular a) b) Fig. 3 dorsal view of anterior portion of disc 5a. Preorbital length greater than distance between spiracles; pelvic fins projecting beyond posterior margin of disc by about 1/3 of their length (Fig. 4a). . . . . . . . . . . . Dasyatis sabina 5b. Preorbital length shorter than distance between spiracles; pelvic fins usu ally not projecting beyond posterior margin of disc, or, if projecting, never by as much as 1/3 their length (Fig. 4b) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Dasyatis say a) Dasyatis sabina b) Dasyatis say Fig. 4 preorbital and interorbital length 6a. Snout projecting beyond remainder of anterior margin of disc, forming a sm all triangular protuberance; dorsal disc region with dense and broad array of blunt tubercles from interorbital area to base of tail region on larger juveniles and adults (Fig. 5) . . . . . Dasyatis guttata 6b. Snout not projecting beyond remainder of anterior margin of disc, not forming a sm all trian- gular protuberance; dorsal disc region without dense and broad array of blunt tubercles from interorbital area to base of tail region on larger juveniles and adults (Fig. 6) . . . . . . . .(cid:1) 7 snout snout not projecting projecting Fig. 5 Dasyatis guttata (dorsal view) Fig. 6 dorsal view 7a. Lateral sides of tail without conspicuous tubercles or thorns; longitudinal fin-fold along ven- tral side of tail about as deep as height of tail . . . . . . . . . . . . . . . . Dasyatis ameri cana 7b. Lateral sides of tail with conspicuous tubercles and thorns in large juveniles and adults; longitudinal fin-fold along ventral side of tail about 1/2 as deep as height of tail . . Dasyatis centroura no conspicuous tubercles or conspicuous thorns tubercles and thorns a) Dasyatis ameri cana b) Dasyatis centroura Fig. 7 lateral view of tail List of species occurring in the area (cid:1) T(cid:1)he symbol is given when species accounts are include. (cid:1) Dasyatis ameri cana Hildebr and and Schroeder, 1928. (cid:1) Dasyatis centroura (Mitchill, 1815). (cid:1) Dasyatis geijskesi Boeseman, 1948. (cid:1) Dasyatis guttata (Bloch and Schneider, 1801). (cid:1) Dasyatis sabina (Lesueur, 1824). Dasyatis say (Lesueur, 1817). (cid:1) Himantura schmardae (Werner, 1904). (cid:1) Pteroplatytrygon violacea (Bonaparte, 1832).

Maximum: 150 cm disc width; males mature at 51 cm disc width, females mature at 75 to 80 cm disc width, and young are 17 to 18 cm at birth.

Oviparous (Ref. 50449). Eggs have horn-like projections on the shell (Ref. 205).

Reproductive mode: dioecism; fertilization: internal (oviduct); nonguarders (open water/substratum egg scatterers); parental care: none. Oviparous, paired eggs are laid. Embryos feed solely on yolk (Ref. 50449).

IUCN Red List Status: Least Concern (LC), assessed 2019-06-21. Resilience: Low (Fec assumed to be <100).