Cocos Pygmygoby, Trimma insularum Winterbottom & Hoese 2015

A pygmygoby with a broad oblique yellow stripe across the cheek. The spcies is endemic to the Australian territory of Cocos (Keeling) Islands in the eastern Indian Ocean.

Cite this page as:
Bray, D.J. 2017, Trimma insularum in Fishes of Australia, accessed 21 Jul 2018,

Cocos Pygmygoby, Trimma insularum Winterbottom & Hoese 2015

More Info


Known only from Cocos (Keeling) Islands (Indian Ocean). 


A species of Trimma with a vertically-sided, ‘U’-shaped interorbital trench and well developed postorbital trench, scales centred on the predorsal midline usually absent (although there may be 1–3 scales anteriorly in the midline, with a narrowly triangular naked area in front of the first dorsal spine); second dorsal spine elongated in adults (>20 mm SL), and may reach posteriorly to the dorsal procurrent caudal fin rays; third spine somewhat elongated, often extending beyond the spine of the second dorsal fin; usually 10 dorsal, 9 anal and 17–19 pectoral-fin rays, the latter with 5–12 branched rays at the middle of the fin, fifth pelvic ray usually branched once and about half the length of the fourth (47–64%); 18–20 total gill rakers on the first gill arch; and bony interorbital width less than half pupil-diameter. 

Similar Species

When freshly collected, this species is immediately distinguishable from all other described species of Trimma by the broad oblique yellow stripe across the cheek.


The specific name insularum is from the Latin ‘insularis’ meaning ‘of an island’, in reference to the distribution of the species, which is apparently confined to the Cocos (Keeling) Islands.

Species Citation

Trimma insularum Winterbottom & Hoese 2015, Zootaxa 3934: 36. Type locality: tidal channel and adjacent sandy area at south end of Direction Is,, Cocos (Keeling) Islands, 12°05'35"S, 96°53'10"E.


Bray, D.J. 2017


Australian Faunal Directory

Cocos Pygmygoby, Trimma insularum Winterbottom & Hoese 2015


Winterbottom, R. & Hoese, D.F. 2015. A revision of the Australian species of Trimma (Actinopterygii, Gobiidae), with descriptions of six new species and redescriptions of twenty-three valid species. Zootaxa 3934: 1-102. DOI: Abstract

Quick Facts

CAAB Code:37428426

Depth:1-49 m

Habitat:Reef associated

Max Size:2.8 cm SL

Native:Endemic (AUS EEZ)

Species Maps

CAAB distribution map