This special fish is seen most frequently at remote sites like Richelieu Rock and Koh Tachai, but has been seen at several other sites with less frequency.

For more information on the other kinds of sharks we see at the Similan islands check our Shark Page. If you are interested in Rays – please see our Similan Island Rays page

Shark Ray

Rhina ancylostoma

Endangered!

Much of this information is from the Australian Museum, as there is little information on this rare shark….

The Shark Ray is a very distinctive, deep-bodied fish which is found widely in the Indo-Pacific.

The upper surface of this species is a blue-grey color with white spots. There is a large blue-edged, black blotch above each pectoral fin and dark bands between the eyes. Unfortunately the specimen in the images has faded and these markings are not visible. This colouration is often not as distinct in large individuals which may only have faint markings.

Some of the most obvious features of this species are the wide, blunt snout, the large thorns on the bony ridges on the head and the large spiracles (the holes in the head behind the eyes). The tail of this species is much longer than the disc. The Shark Ray belongs in the family Rhinchobatidae (the guitarfishes). Two of the characters that separate the guitarfishes from other fishes are the well developed lower caudal fin lobe and the distinct demarcation between the head and pectoral fins. Both of these characters are clearly visible in the top image.

The Shark Ray is a very distinctive, deep-bodied fish which is found widely in the Indo-Pacific.

The upper surface of this species is a blue-grey colour with white spots. There is a large blue-edged, black blotch above each pectoral fin and dark bands between the eyes. Unfortunately the specimen in the images has faded and these markings are not visible. This coloration is often not as distinct in large individuals which may only have faint markings.

Some of the most obvious features of this species are the wide, blunt snout, the large thorns on the bony ridges on the head and the large spiracles (the holes in the head behind the eyes). The tail of this species is much longer than the disc. The Shark Ray belongs in the family Rhinchobatidae (the guitarfishes). Two of the characters that separate the guitarfishes from other fishes are the well developed lower caudal fin lobe and the distinct demarcation between the head and pectoral fins. Both of these characters are clearly visible in the top image.

The Shark Ray is not dangerous to humans. It uses its flattened pavement-like teeth to feed on crabs and shellfish.

On the Similan Islands we find these most frequently at Richelieu Rock. In addition sightings have occurred at Koh Tachai, Shark Fin Reef and Boulder city.