Skip to main content

Bobward’s Bluespotted Maskray: Neotrygon bobwardi

Family: Dasyatidae
Common names

Bobward’s Bluespotted Maskray, Sumatran Bluespotted Maskray.

Binomial

Neotrygon bobwardi.

Synonyms

None.

Identification

Bobward’s Bluespotted Maskray is identified through molecular markers (mitochondrial DNA) rather than unique physical traits. Consequently, the following physical characteristics are general approximations.

A small stingray with a kite-shaped disc that is wider than long. Snout bluntly angular. Tip of snout not extended. Anterior margins of disc weakly convex. Pectoral fin apices angular. Pelvic fins large; apices narrowly rounded.
Eyes large and protruding. Mouth small. Prominent labial furrows and folds around mouth. Nasal curtain narrow and skirt-shaped.
Tail broad and depressed at base, tapering gently to caudal sting, then thin but firm to tip. Tail length (when intact) approximately up to 1.5 x disc width. Ventral finfold long and low. Dorsal finfold very short; approximately .2 x ventral fold length. 1-2 tail stings usually present.

Colour

Colour description based on personal observations of numerous individuals from northern Sumatra. Dorsum brownish grey with a distinct golden to reddish brown band across eyes, a relatively sparse scattering of roughly eye-sized pale blue spots, and numerous small black flecks. Blue spots mostly confined to pectoral fins. Small oval gap in mask/band between eyes. Small cluster of black spots centrally posterior to eyes. Ventrum white/pale. Tail pale blue dorsally from base to beyond caudal stings, then irregular black and white bands to tip. Caudal finfolds pale blue.

Size

Maximum disc width unknown.

Bobward's Bluespotted Maskray, Neotrygon bobwardi, aka Sumatran Bluespotted Maskray. Pulau Weh, Sabang Island, Sumatra, Indonesia, Indian Ocean.

Conservation Status

NEAR THREATENED

Bobward’s bluespotted maskray has not been assessed by the IUCN. Most assessed maskrays in Southeast Asia are listed as ‘Least Concern’, but maskrays in general are targeted and a retained bycatch in fisheries throughout most of their ranges.

Bobward's Bluespotted Maskray, Neotrygon bobwardi, aka Sumatran Bluespotted Maskray. With Bluestreak Cleaner Wrasse (Labroides dimidiatus). Pulau Weh, Sabang Island, Sumatra, Indonesia, Indian Ocean.
Habitat

Tropical seas. On sandy substrates, often adjacent to reefs. Intertidal to at least 15m

Distribution

Bobward’s bluespotted maskray is found around northern Sumatra, from Sabang Island southward to at least Padang.

Reproduction

Aplacental viviparity. Litter size unknown.

Diet

Diet unknown.

Behavior

Rests in shallow water under a covering of sand by day. Becomes more active towards dusk. I have observed individuals closely following each other even when one animal was already clearly gravid.

Reaction to divers

Fairly easy to approach especially when accustomed to divers.

Diving logistics

Bobward’s bluespotted maskray is abundant off the northern tip of Sumatra around Pulau Weh (aka Sabang Island). In Sabang Bay, I have seen dozens on a single shore dive.