Comprehensive DescriptionRead full entry
Batrachocephalus ZBK Bleeker, 1846
Diagnosis. The combination of exclusive (1 to 6) and non-exclusive (7 to 14) characters define and distinguishes Batrachocephalus ZBK from all other ariid genera: (1) accessory tooth plates located between lateral ethmoid and premaxilla; (2) nasal fan shaped; (3) anterior part of opercle subrectangular (fig. 24); (4) lateral portion of ceratohyal columnar and very strong; (5) third basibranchial cup-shaped, very long and thin (fig. 25); (6) maxillary barbel absent; (7) mesethmoid very wide at median portion (shared with Bagre , Brustiarius ZBK , Carlarius , Cochlefelis ZBK , Doiichthys ZBK , Sciades couma , S. emphysetus ZBK , S. guatemalensis , S. herzbergii ZBK , S. leptaspis , S. passany and S. proops ); (8) accessory tooth plates small and oval-shaped (shared with Cathorops , Cephalocassis melanochir , Cryptarius ZBK , Doiichthys ZBK and Hemiarius ZBK ); (9) posterior cranial fontanel absent [shared with Sciades (with exception of S. platypogon )]; (10) epiphyseal bar indistinct [shared with Sciades (with exception of S. platypogon )]; (11) lachrymal with two anterior and one mesial branches (fig. 26) (shared with Bagre ); (12) epihyal long its length more than 1.5 longer than its depth (fig. 27) (shared with Bagre , Brustiarius ZBK and Cochlefelis ZBK ); (13) urohyal anterior margin not notched (shared with Cathorops and Plicofollis ZBK platystomus ); (14) second dorsal process of cleithrum parallel to posterior cleithral process [shared with Aspistor ZBK , Bagre , Brustiarius ZBK , Carlarius , Cinetodus ZBK , Cochlefelis ZBK , Neoarius ZBK , Netuma , Notarius ZBK , Pachyula ZBK , Potamosilurus (with exception of P. velutinus ) and Sciades ].
Supplementary morphological characters. Cephalic shield granulated visible under the skin; very small fenestra limited by frontal and lateral ethmoid bones barely visible under the skin; medial groove of neurocranium very distinct, limited by frontal bones and/or on supraoccipital; posterior cranial fontanel entirely closed at all stages of development; fenestra limited by supraoccipital, pterotic and sphenotic absent; fossa limited by pterotic, supracleithrum and extrascapular very well developed; epioccipital not invading into dorsal portion of cephalic shield; occipital process short, progressively narrower toward its posterior part; anterior and median nuchal plates fused, indistinct forming a structure of semi-lunar aspect; vomerine tooth plates absent; accessory tooth plates narrow and transversely elongate, bearing molariform teeth; maxillary barbel absent; two pairs of mental barbels; base of adipose fin moderately long, about half the length of anal-fin base; lateral line bifurcated at caudal region, reaching base of caudal-fin upper and lower lobes; cleithrum wide, with second dorsal process on its upper portion; posterior cleithral process moderately long and distinct from second dorsal process of cleithrum.
Distribution and habitat. South and southeast Asia, marine and brackish waters.