Bagre Cloquet, 1816

(fig. 14)

Bagre Cloquet, 1816: 52. Type species: Silurus bagre Linnaeus, 1766. Type by absolute tautonymy. Gender: masculine.

Bagre Oken, 1817: 1183. Type species: Silurus bagre Linnaeus, 1766. Type by absolute tautonymy. Gender: masculine.

Glanis Spix & Agassiz, 1829: 46. Type species: Silurus bagre Linnaeus, 1766. Type by subsequent designation by Kottelat(1988). Gender: Masculine.

Stearopterus Minding, 1832: 116. Type species: Stearopterus bagre Minding, 1832. Type by monotypy. Gender: masculine.

Breviceps Swainson, 1838: 328 and 343 (pre-occupied in Merrem, 1820). Type species: Silurus bagre Bloch, 1794. Type by monotypy. Gender: neuter.

Felichthys Swainson, 1839: 305. Type species: Silurus bagre Bloch, 1794. Type by being a replacement name. Replacement for Breviceps Swainson, 1838. Gender: masculine.

Ailurichthys Baird & Girard, 1854: 26. Type species: Silurus marinus Mitchill, 1815. Type by subsequent designation by Jordan & Evermann (1896). Gender: masculine.

Mystus Gray, 1854: 155 (pre-occupied in Scopoli, 1777). Type species: Mystus carolinensis Gronow, 1854. Type by subsequent designation by Jordan & Evermann (1896). Gender: masculine.

Anemanotus Fowler, 1944: 171. Type species: Ailurichthys panamensis Gill, 1863. Type by original designation. Originally a subgenus of Ailurichthys. Gender: masculine.

Diagnosis. The following exclusive (1 to 13) and shared (14 to 26) characters distinguishes Bagre from the remaining ariid genera: (1) about half of anterior cranial fontanel limited by posterior branches of mesethmoid (fig. 15); (2) anterior infraorbital shaped like number seven (fig. 16); (3) posterior infraorbital conspicuously curved medially (fig. 16); (4) lower end of subvertebral process rounded; (5) maxillary long and thin (fig. 17); (6) maxillary condyles well developed (fig. 17); (7) palatine claviform, anteriorly very broad (fig. 18); (8) lower part of palatine with a bony crest (fig. 18); (9) anterior process of metapterygoid very large (fig. 19); (10) third basibranchial hourglass shaped its posterior portion shorter and wider than anterior; (11) second dorsal process of cleithrum on inferior part of lateral face of this bone (fig. 20); (12) maxillary barbel compressed, tape-like; (13) one pair of mental barbells; (14) lachrymal with two anterior and one mesial branches (fig. 21) (shared with Batrachocephalus); (15) occipital process ventral crest developed through the entire length of the process (shared with Amphiarius, Aspistor, Cathorops, Cephalocassis, Cinetodus, Hemiarius, Nedystoma, Nemapteryx, Pachyula and Sciades platypogon); (16) contact face between transcapular process and basioccipital wide and depressed (shared with Amphiarius, Arius gagora, A. maculatus, A. manillensis, Aspistor, Cathorops, Cryptarius, Doiichthys, Nedystoma, Nemapteryx, Notarius, Plicofollis platystomus and Potamosilurus latirostris); (17) parasphenoid wing process very long and thin [shared with Amphiarius, Aspistor, Cathorops (with exception of C. dasycephalus), Cochlefelis, Hemiarius, Notarius (with exception of N. planiceps), Pachyula, Plicofollis platystomus, Potamarius, Potamosilurus (with exception of P. velutinus), Sciades emphysetus, S. passany and S. proops]; (18) face for articulation between palatine and lateral ethmoid slightly displaced to the anterior portion of former bone (fig. 18) (shared with Doiichthys); (19) tip of urohyal medial process bifid (fig. 22) (shared with Doiichthys); (20) urohyal lateral processes as long as or longer than medial process (fig. 22) (shared with Potamarius); (21) transversal crest associated with neural spine of fourth vertebra very high (shared with Amphiarius, Batrachocephalus, Cathorops, Cinetodus, Cryptarius, Ketengus, Hemiarius, Nemapteryx, Nedystoma, Notarius planiceps, Osteogeneiosus, Pachyula and Sciades platypogon); (22) median crest associated with neural spine of third vertebra very high (shared with Amphiarius, Aspistor, Cathorops, Cephalocassis, Cinetodus, Hemiarius, Nedystoma, Nemapteryx, Pachyula and Sciades platypogon); (23) more than 39 caudal vertebrae (shared with Cochlefelis); (24) base of adipose fin very short, less than one-half as long as anal-fin base [shared with Brustiarius, Cathorops, Cryptarius, Netuma and Plicofollis (with exception of P. platystomus)]; (25) pectoral-fin spine prolonged as a tape-like filament (shared with Arius madagascariensis); (26) lateral line bifurcated at caudal region (shared with Arius, Batrachocephalus, Ketengus, Netuma, Osteogeneiosus, Plicofollis and Sciades couma).

Supplementary morphological characters. Cephalic shield smooth, covered by muscle and scarcely visible under the skin; a well developed fenestra limited by frontal and lateral ethmoid bones visible under the skin, but sometimes obliterated by superficial ossifications; medial groove of neurocranium not very distinct, limited by frontal bones and/or on supraoccipital; posterior cranial fontanel very reduced in small specimens, sometimes completely closed in large adult specimens; fenestra limited by supraoccipital, pterotic and sphenotic absent; fossa limited by pterotic, supracleithrum and extrascapular varying in size; epioccipital not invading dorsal portion of cephalic shield; occipital process short, progressively narrower toward its posterior part; anterior and median nuchal plates fused, indistinct (except in B. bagre) forming a structure of semi-lunar aspect; vomerine tooth plates present and transversely elongate; accessory tooth plates narrow and transversely elongate, bearing conical teeth; maxillary barbel basally bony, fleshy for remaining part of its length and compressed in form of tape; a single pair of mental barbels; base of adipose fin very short, less than onehalf 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 lower portion; posterior cleithral process moderately long and distinct from second dorsal process of cleithrum.

Remarks. The genera Bagre Cloquet, 1816, Bagre Oken, 1817, Glanis, Stearopterus, Breviceps non Merrem, 1820, Felichthys, Mystus non Scopoli, 1777 were established based on the same type-species, Silurus bagre Linnaeus, 1766 and are therefore objective synonyms (Code of Zoological Nomenclature, article 61b).

Ailurichthys and Anemanotus, represented respectively by the type-species, Silurus marinus Mitchill, 1815 and Aelurichthys panamensis Gill, 1863, are subjective synonyms. The nominal genus Breviceps Swainson, 1838 and Mystus Gray, 1854 are invalid since the names are pre-occupied. Breviceps was replaced by Felichthys Swainson, 1839.

Distribution and habitat. Eastern and western America, predominantly marine waters, but also in brackish waters.