Microgobius thalassinus

Common Name

Green Goby

Year Described

Jordan & Gilbert, 1883


Dorsal Fin: VII, 15-17 (usually 16)
Anal Fin: 15-17
Pectoral Fin: 19-23 (usually 21-22)
Gill Rakers: 5+16
Scales: 43-50 rows

Body elongate. Mouth large and upturned. Dentary with 7-9 teeth. Females with a poorly developed fleshy dorsal crest. Males with no dorsal crest. There are two preopercular pores. Supraorbital canals usually joined between eyes. Dorsal spines slightly elongate in males but not elongate in females. Body covered in cycloid scales, except for a ctenoid patch under the pectoral fin.


Body greenish with a yellow cast dorsally. Area under pectoral fin brilliantly blue or at least chevrons of pale blue. Head same as body but with a reticulated network of iridescent green lines and spots over a reddish background. The markings form two rough lines. Base of pectoral fin blue. Belly and lower head pale yellowish. Eye greenish. Spiny dorsal pale green basally with a pale median band and red margin. Rear of fin with a black blotch. Soft dorsal with a strong yellow stripe bordered by red on both sides. Distal part of fin pale blue with a red margin. Caudal fin mottled with blues, greens, yellows, and a red upper margin. Anal fin dusky blue. Pelvic fin yellowish. Pectoral fin clear with a dark base.


Maximum size to 60mm SL.


Muddy sand to mud bottoms from 0-6m. Inhabits seagrass beds and estuaries.


Virginia to S. Florida, and the northern Gulf of Mexico from Florida to Texas.


Birdsong, R.S. 1981. A review of the gobiid fish genus Microgobius Poey. Bulletin of Marine Science v. 31 (no. 2): 267-306.

Tornabene, L. , J.L. van Tassell and D.R. Robertson. 2012. Microgobius urraca (Teleostei: Gobiidae), a new species of goby from the tropical eastern Pacific. Zootaxa No. 3447: 41-55.