Osteogeneiosus Bleeker, 1846 (fig. 71) Osteogeneiosus Bleeker, 1846: 173. Type species: Arius militaris Valenciennes, 1840 (= Silurus militaris Linnaeus, 1758). Type by subsequent designation by Bleeker (1862: 8; 1863: 93). Gender: Masculine. Diagnosis. Osteogeneiosus can be differentiated from all other members of the Ariidae by the combination of the following exclusive (1 to 9) and shared (10 to 15) characters: (1) nasal anterior portion notably curved; (2) bony blade anteriorly connecting nasal tubules absent; (3) lachrymal with three anterior and one lateral branches (fig. 72); (4) maxillary thin and very elongate (fig. 73); (5) maxillary condyles very large (fig. 73); (6) palatine cylindrical very thick and short (fig. 74); (7) posterior cartilage of palatine vestigial; (8) metapterygoid low and elongate, its greatest depth three times in its length (fig. 75); (9) mental barbels absent; (10) vomer posterior process very thin from its base [shared with Plicofollis (with exception of P. tenuispinis and P. platystomus)]; (11) fenestra delimited by lateral ethmoid and frontal bones well developed (shared with Amphiarius, Cathorops, Cephalocassis, Cryptarius, Doiichthys, Hemiarius, Nedystoma and Nemapteryx); (12) mesial laminar projection on frontal bones absent (shared with Amphiarius, Arius, Aspistor, Cathorops, Cephalocassis, Cryptarius, Doiichthys, Galeichthys, Hemiarius, Nedystoma, Nemapteryx, Potamarius and Potamosilurus latirostris); (13) anterior cartilage of palatine short, less than 1/3 on bone length (fig. 74) (shared with Bagre and Galeichthys); (14) urohyal medial process short (shared with Galeichthys); (15) space limited by posterior epioccipital process and crests associated with fourth vertebra very reduced, restricted to anterior portion [shared with Arius, Carlarius, Brustiarius, Cochlefelis, Genidens, Neoarius, Netuma, Plicofollis (with exception of P. platystomus and P. tenuispinis), Potamarius grandoculis, Potamosilurus and Sciades (with exception of S. platypogon)]. Supplementary morphological characters. Cephalic shield granulated visible under the skin; a large fenestra limited by lateral ethmoid and frontal visible under the skin; medial groove of neurocranium very distinct, limited by frontal bones and/or on supraoccipital; posterior cranial fontanel moderately developed, long and narrow; fenestra limited by supraoccipital, pterotic and sphenotic absent; fossa limited by pterotic, supracleithrum and extrascapular relatively large; epioccipital not invading dorsal portion of cephalic shield; occipital process triangular, moderately long and narrow, progressively narrower toward its posterior part; anterior and median nuchal plates fused and indistinct, forming a structure of semi-lunar aspect; tooth plates associated with vomer absent; accessory tooth plates longitudinally elongate, bearing molar-like teeth; maxillary barbel cylindrical and bony along its entire extension; base of adipose fin moderately long, about half as long as 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.

Published as part of Alexandre P. Marceniuk & Naércio A. Menezes, 2007, Systematics of the family Ariidae (Ostariophysi, Siluriformes), with a redefinition of the genera., pp. 1-126 in Zootaxa 1416 on pages 85-87