Ring-eye pygmygoby (Trimma benjamini)

Latin name

Trimma benjamini 

Other name

Trimma benjamini 

Identification

This species is characterized by the presence of the following features: Deep concave "U" shaped interorbital cavity; bony interorbital cavity about half the diameter of the pupil; with a small groove behind the eye; without medium sized anterorbital scales, sides of occiput covered with small scales reaching to or near the eye; cheeks and cap without scales; base of pectoral fin with medium sized oval scales; Pectoral region with 5-6 rows of cycloid scales, isthmus bare anteriorly, with one slightly enlarged scale on band between bases of pelvic fins; central 6-13 pectoral rays branched, uppermost and lowest rays unbranched; Fifth pelvic fin ray once dichotomously branched and about 60-75% of length of fourth; all other rays usually with one successive branch, basal membrane connecting two pelvic fins only at base; second dorsal spur longest, usually filiform, extending from base. 

Features of fish fins

Dorsal spines (total): 7; Dorsal soft rays (total): 9 - 10; Anal spines: 1; Anal soft rays: 8 - 10. 

Fish colouring

Head and trunk red in life, yellow in preservation, with a thin vertical band of gray (bluish gray in life) running from the anteroventral margin of the eye to the center of the jaws, and a second band running more or less vertically down the cheek from about the center of the eye. The orbit is bordered by a thin band of melanophores, more distinct on the dorsal side, but faded in the preserved material.

Distribution

Widespread in the western Pacific: from Sulawesi to Tonga; north to the Marshall Islands; south to New Caledonia and the Great Barrier Reef.

Habitat

A marine tropical species. Depth range 1 to 90 m, usually 4 to 35 m. Inhabits inshore and outer reef slopes. 

Size

Maximum length 3 cm. Maximum reported age 0.39 years.

Behavior

They inhabit the benthos and occur singly or in loose groups.  

Food and feeding habits

Ring-eyed pygmy gobies feed on plankton.

Reproduction

Larvae have a long pelagic life span of 33.9 days (= 24% of maximum life span) and linear postlarval growth. Daily mortality ranges from 2.9% to 6.3%; sex ratio 1:1.6 males/females).

Fishing

Of no commercial value or interest to fishermen.

Relationship with a person

Harmless.