Borneo sand Skate

📖 Overview

Borneo sand Skate (Okamejei cairae) is a ray-finned fish of the family Rajidae. It inhabits marine (saltwater) waters. This species can reach a maximum total length of 36 cm. It occurs at depths between 65 and 150 metres. With a trophic level of 4, it is a mid-level predator. It is assessed as Vulnerable on the IUCN Red List.

🔬 Taxonomy

🐟 Physical Description

This species is distinguished by the following set of characters: disc with narrowly rounded apices, not broad, width 61-70% TL, 1.2-1.3 times its length; snout angle 84-106°; moderately long tail, length 0.9-1.1 in distance from snout tip to rear of cloaca; slender tail, width 1.2-1.7 times height at its midlength, 1.1-1.7 times at first dorsal-fin origin; pre-upper jaw length 14-16% TL, 1.8-2.1 times internasal width; ventral length 27-30% TL; snout length 2.8-3.6 times interorbital width; orbit diameter 93-103% interorbital width in large males, 69-89% in females; first dorsal-fin height 2.3-3.0 its base length; distance from first dorsal-fin origin to tail tip 4.1-5.4 times first dorsal-fin base length, 2.9-3.2 times caudal-fin length; medium sized pelvic fins, length of posterior lobe 15-17% TL, length of anterior lobe 78-92% of posterior lobe; adult clasper about 22% TL, connected to pelvic-fin inner margin at about 40% of its length from cloaca in adult male; clasper glans expanded slightly, soft, claw-like funnel; anterior margins of both surfaces of disc of males with denticle bands, no dorsal bands in females and juveniles; 1-3 nuchal thorns present; malar thorn patch elongate and posteriorly positioned; tail thorns very small (rudimentary and possibly deciduous in mature males), in 5 irregular rows in both sexes and juveniles; total pectoral radials 78-84; centra: trunk 24-31, predorsal 68-75, total 123-141; 40-51 tooth rows in upper jaw; mainly yellowish to brownish with variable size clusters of fine brownish spots (sometimes faint) over most of dorsal disc; rostral cartilage not strongly demarcated from rest of snout; prominent, dark brown ocellate markings near rear tip, and often near center of each pectoral fin; ventral surface usually pale to medium greyish brown over head and abdomen, distinctly darker than paler area around margin of disc; ventral sensory pores large, silvery white with dark margins when fresh, uniformly black in preservative, not surrounded by greyish blotches, none on abdomen and pelvic girdle; each dorsal fin with a dark anterior saddle, caudal fin with 2 dark bars .: other.

🌀 Behaviour

Behavioural data for Borneo sand Skate is currently being reviewed.

🦐 Diet

Diet information for Borneo sand Skate is currently being compiled.

🥚 Reproduction

🌍 Habitat & Distribution

Marine; benthopelagic; depth range 65 - 150 m . Tropical South China Sea.

🌿 Ecology

📐 Morphometrics

🌡️ Water Parameters & Tolerance

🛡️ Conservation Assessment

📊 Population Risk & Fisheries

🐠 Related Species

🔍 Similar Species

👥 Community & Contribute