Bluespot Damsel (species: Pomacentrus grammorhynchus) in taxonomy (Lizard Island Field Guide)
Pomacentrus grammorhynchus
Bluespot Damsel

©Andy Lewis: An adult Bluespot Damsel showing the distinct purple cheek spots bright blue dot on the caudal peduncle

©Andy Lewis: A juvenile Bluespot Damsel

©Andy Lewis: A subadult Bluespot Damsel
Kingdom Animalia
Phylum Chordata
Class Actinopterygii
Order Perciformes
Family Pomacentridae
Genus Pomacentrus
Species Pomacentrus grammorhynchus



Distinguishing features

A small herbivorous damselfish with a dark brown body, and yellowish brown tail. The small juveniles have dark upperparts, a yellow belly, an ocellus on the rear of the dorsal fin, and a series of electric blue lines on the forehead. There is a distinct electric blue dot on the caudal peduncle and pink-purple blotches on the lower cheek which are retained through to the adult stage. Distinguish from the closely related P. wardi adult by the blue dot on the caudal peduncle and pink-purple blotches on the lower cheek, and from the juvenile P. wardi by the thicker blue lines on the head and larger spot on the peduncle.


  • Up to 12 cm (Standard length)

Depth range

  • Depth range data is not yet available.



©Atlas of Living Australia: Australian distribution

Distribution and habitat preferences

Shallow patch reefs and reef flats with a mixture of hard coral cover and dead corals covered in turf algae.

Found in most locations around the Island, except reef crests.


The Blue spot Damsel is superficially similar to Ward's Damsel in appearance, however the Bluespot damsel is not as abundant, and usually lives in small colonies with a distinct algal farm, as opposed to Ward's damsels which are more widely dispersed and less manipulative of the algal community. The Bluespot is thicker set and dominant to Ward's damsel where the two cohabit, and tend to establish farms near thickets of staghorn Acropora coral, often on the edge of territories of Stegastes lividus. The small juveniles feed on plankton initially, but then soon stake out a territory of their own on the edge of an adult colony, and start to feed on benthic algae.

Web resources


  • Booth, D.J. and G.A. Beretta (2002). Changes in a fish assemblage after a coral bleaching event, Marine Ecology Progress Series, 245: 205-212. LIRS catalog number 90108.
  • Caley, M.J. (1991). Mechanisms of coexistence in communities of coral-reef fishes, Ph.D. thesis, University of Sydney. LIRS catalog number 307.
  • Caley, M.J. (1995). Community dynamics of tropical reef fishes: local patterns between latitudes, Marine Ecology Progress Series, 129: 7-18. LIRS catalog number 447.
  • View all references