Morphology Data of Rhinobatos borneensis
Identification keys
Main Ref. Last, P.R., B. Séret and G.J.P. Naylor, 2016
Appearance refers to
Bones in OsteoBase

Sex attributes

Specialized organs
Different appearance
Different colors

Descriptive characteristics of juvenile and adult

Striking features
Body shape lateral elongated
Cross section flattened
Dorsal head profile
Type of eyes
Type of mouth/snout
Position of mouth
Type of scales placoid scales

This species is distinguished by the following characters in adults: a wedge-shaped disc, its width 29-31% TL and length 1.30-1.42 times width; snout length 2.5-3.3 times the interspiracular distance, 3.8-5.6 times the interorbital width; medium-sized orbit, 1.5-2.2 times the spiracle length; nostrils weakly oblique, length 1.5-1.7 times internarial distance; preoral length 7.4-8.1 times the internarial distance; anterior nasal flaps are penetrating slightly into internarial space but well separated at their insertion (not reaching level of inner corner of nostril); posterior nasal flaps are broad; spiracular folds 2, the outermost fold distinctly taller than inner fold; ridges of rostral cartilage almost parallel, converging slightly anteriorly but not constricted medially; anterior cartilage sickle-shaped, pointed or blunt posteriorly; distance between fifth gill slits 2.7-3.3 times in ventral head length; prebranchial sensory pore patch obvious, extending to just behind first gill slit; postscapular sensory canal apparent with exposed lateral pores, grooved; thorn patches present on supraorbit, scapular region, and dorsal midline rudimentary, not evident; in males pelvic-fin inner margin subequal to its base, shorter in females; interdorsal distance 2.5-3.3 times first dorsal-fin base; dorsal caudal margin 1.9-2.3 times preventral margin; upper jaw with ca. 90 tooth rows; post-synarcual centra 176-180; nasal lamellae 50-53; dorsal fin usually with a large, often faint, central dusky blotches; in adults dorsal disc yellowish or brownish, often with diffuse pale yellowish blotches, without white spots; young with ocellate markings (Ref. 108568).

Ease of Identification

Meristic characteristics of Rhinobatos borneensis

Lateral Lines Interrupted: No
Scales on lateral line
Pored lateral line scales
Scales in lateral series
Scale rows above lateral line
Scale rows below lateral line
Scales around caudal peduncle
Gill clefts (sharks/rays only)
Gill rakers
on lower limb
on upper limb


Dorsal fin(s)

Fins number
Finlets No. Dorsal   
Spines total
Soft-rays total
Adipose fin

Caudal fin


Anal fin(s)

Fins number
Spines total
Soft-rays total

Paired fins

Pectoral Attributes  
Pelvics Attributes  
Main Ref. (e.g. 9948)
Glossary ( e.g. cephalopods )
Entered by Capuli, Estelita Emily
Modified by Bailly, Nicolas
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cfm script by eagbayani, 17.10.00, php script by rolavides, 13/03/08 ,  last modified by sortiz, 06.27.17