Ketengus
Creators: name: Alexandre P. Marceniuk
name: Naércio A. Menezes
Publisher: name: Zenodo
Year: 2007
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Actinopterygii
Siluriformes
Ariidae
Ketengus

description: Ketengus Bleeker, 1847
(fig. 58)
Ketengus Bleeker, 1847: 167. Type species: Ketengus typus Bleeker, 1847. Type by monotypy. Gender: masculine.
Diagnosis. Ketengus can be differentiated from all other members of the Ariidae by exclusive (1 to 9) and shared (10 to 19) characters: (1) fenestra delimited by mesethmoid and lateral ethmoid wide and filled with cartilage (fig. 59); (2) vomer diamond shaped (fig. 60); (3) vomerine lateral processes absent (fig. 60); (4) a single point of contact between lateral ethmoid and frontal (fig. 59); (5) lachrymal with three anterior branches (fig. 61); (6) tooth band on dentary reaching posterior end of bone; (7) dorsal crest of premaxilla, delimiting contact area between mesethmoid and premaxilla absent; (8) second and third basibranchials indistinct(fig. 62); (9) first and second hypobranchials boomerang shaped (fig. 62); (10) posterior horn of mesethmoid tubular and thin (fig. 59) [shared with Cathorops (with exception of C. dasycephalus)]; (11) mesethmoid posterior branches thin (fig. 59) [shared with Bagre (with exception of B. panamensis), Cathorops, Cephalocassis, Doiichthys, Nedystoma and Nemapteryx]; (12) mesethmoid posterior branches parallel over their entire length (fig. 59) (shared with Cathorops, Cephalocassis, Doiichthys, Nedystoma and Nemapteryx); (13) accessory tooth plates absent (shared with Cephalocassis borneensis, Nedystoma, Pachyula, Potamarius izabalensis and Potamosilurus velutinus); (14) anterior portion of opercle subtriangular (shared with Cochlefelis, Sciades emphysetus, S. passany and S. proops); (15) posteroventral portion of opercle little pronounced posteriorly [shared with Bagre panamensis, Carlarius (with exception of C. heudelotii), Galeichthys, Genidens, Plicofollis (with exception of P. platystomus) and Sciades (with exception of S. couma and S. felis)]; (16) hyomandibular lower crest absent (shared with Cathorops and Cephalocassis); (17) second epibranchial overlaying first (shared with Bagre and Galeichthys); (18) third pharyngobranchial not mesially angulated hourglass shaped (shared with Doiichthys and Potamarius grandoculis); (19) seventh vertebra anterior most element free from lower superficial ossification (shared with Amphiarius, Aspistor, Cathorops, Cephalocassis, Cinetodus, Cryptarius, Doiichthys, Galeichthys, Hemiarius, Nedystoma, Nemapteryx and Pachyula).
Supplementary morphological characters. Cephalic shield granulated visible under the skin; fenestra between lateral ethmoid and frontal absent; 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, short and moderately large, 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 absent; maxillary barbel fleshy; two pairs of mental barbels; base of adipose fin moderately long, about half as long as anal-fin base length; lateral line bifurcated at caudal region, reaching base of caudal-fin upper and lower lobes; cleithrum wide with second dorsal process on upper its portion; posterior cleithral process of moderate size, distinct from dorsal process of cleithrum.
Distribution and habitat. South and southeast Asia, brackish waters.
description: 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 69-72