Sulu Sea Skate

This small to medium-sized rostrorajin skate (to about 53 cm TL) is distinguished by the following combination of characters: disc possess narrowly to broadly rounded apices, its width 59-71% TL, 1.1-1.2 times its length; snout angle is 88-98°; tail relatively short in females (length 0.8-0.9 in distance from snout tip to rear of cloaca) and longer in adult male (length 1.1 times distance from snout tip to rear of cloaca); tail width 1.5-1.8 times height at its midlength, 1.4-1.7 times at first dorsal-fin origin; pre-upper jaw length is 17-18% TL, 2.0-2.2 times internasal width; ventral head length is 29-32% TL; snout length is 3.3-3.4 times interorbital width; orbit diameter 67-85% interorbital width; first dorsal-fin height 2.0-2.7 in its base length; long procaudal length, its distance from first dorsal-fin origin to tail tip 3.1-4.0 times first dorsal-fin base length, 3.2-6.3 times caudal-fin length; the pelvic fins of medium size, length of posterior lobe 16-18% TL, length of anterior lobe 71-83% of posterior lobe; adult male without malar thorn patches; alar thorn patches are small, broadly oval; adult clasper with greatly extended components spike and sentinel; accessory terminal 2 cartilage with strongly articulated medial distal extension, partly overlaying axial cartilage on median margin; anterior margins of both surfaces of disc of females with narrow denticle bands; the single median series of thorns extending along entire midline of disc; tail thorns are well developed, numerous, in 3 closely spaced median rows and irregular lateral row on each side (absent from dorsolateral region of tail); thorns in central median row fewer and smaller than in rows adjacent; 80-82 total pectoral radials; 26-31 trunk centra; 79-85 predorsal centra; 133-138 total centra; 61-76 tooth rows in upper jaw. Colouration: brownish and white spotted, with large dark pectoral spots bordered with smaller white spots when fresh; rostral cartilage is demarcated from rest of snout; ventral surface whitish with outer margins of pectoral fins yellowish; ventral sensory pores are minute, indistinct, not black-edged or surrounded by greyish blotches; dorsal fins are dark anteriorly, paler posteriorly; the caudal fin pale or brownish (Ref. 112881).