Halobatrachus didactylus

Author: Schneider, 1801

Halobatrachus didactylus Schneider, 1801

Status in World Register of Marine Species:
Accepted name: Halobatrachus didactylus (Bloch and Schneider, 1801) (updated 2009-06-25)

Diagnosis: body robust, head wide and a little depressed. Eyes on top of head, widely separated, with a group of small tentacles from tubular anterior nostrils; mouth large, with 3 rows of small teeth at front, a series of small flaps of skin under lower jaw. Upper angle of operculum with 2 short spines and another on suboperculum. Two dorsal fins, the first with 3 short spines, the second with 19-24 soft finrays; pectoral fins large, reaching almost to anal fin origin; pelvic fins in advance of pectorals; anal finrays 15-17. Scales present, small, embedded and not obvious; 2 lateral lines, the upper with about 48 pores, the lower with about 40. Colour: body mottled with brown spots on white or yellow producing a reticulated pattern overlaid by 3 dark transverse bands on head and 3 or 4 on upper part of body, oblique lines of dark spots on soft dorsal and anal fins, and concentric spots on pectoral and caudal fins. Size: to 50 cm SL.

Habitat: benthic on soft sand or mud, often partly buried, or concealed in rock crevices, solitary, in shallow water down to about 50 m. Food: crustaceans, molluscs, small fishes. Reproduction: no data.

Distribution: eastern Atlantic (a single record from Kattegat, southern Bay of Biscay, Iberian coasts and southward, including Madeira) and Mediterranean (western part, but including Adriatic). Elsewhere, southward along coast of West Africa to Ghana.

Eggs, larvae and young stages. No data on the eastern Atlantic species but for useful information on the western Atlantic Opsanus Tau cf.: Storer, 1858: 272-273 | A. Agassiz, 1882: 279-280, pl. XVI (fig. 1)| Ryder, 1886, pl. 48, pl. I | Clapp, 1891: 494-501, fig. I-III | Wallace, 1898: 9-16, pl. II-III.
Otoliths (sagitta). Chaine, 1938: 88-94, pl. XI (3 upper rows) | Bauzá Rullán, 1959: 92-93, pl. I (fig. 15) and II (fig. 16) | Schmidt, 1968: 64, pl. 13 (fig. 182) and 25.