Carlarius, Alexandre P. Marceniuk & Naércio A. Menezes, 2007

Alexandre P. Marceniuk & Naércio A. Menezes, 2007, Systematics of the family Ariidae (Ostariophysi, Siluriformes), with a redefinition of the genera., Zootaxa 1416, pp. 1-126 : 36-37

Carlarius new genus

(fig. 29)

Type species: Arius heudelotii Valenciennes, 1840.

Diagnosis. Three shared characters distinguishes Carlarius from the remaining ariid genera: (1) mesethmoid wide at its median portion (shared with Amphiarius , Arius caelatus , A. madagascariensis , Aspistor , Cryptarius , Galeichthys , Genidens , Hemiarius , Nedystoma , Nemapteryx , Neoarius , Netuma , Notarius , Plicofollis , Potamosilurus and Sciades assimilis , S. bonillai , S. felis , S. platypogon , S. sagor and S. seemanni ); (2) tooth plates associated with vomer absent [shared with Amphiarius , Arius , Batrachocephalus , Cathorops (with exception of C. dasycephalus ), Cephalocassis , Cinetodus , Cryptarius , Doiichthys , Genidens genidens , Ketengus , Nedystoma , Osteogeneiosus , Pachyula , Plicofollis platystomus , Potamarius and Potamosilurus velutinus ]; (3) epioccipital dorsally exposed [shared with Amphiarius rugispinis , Aspistor , Cinetodus , Pachyula and Plicofollis (with exception of P. platystomus and P. tenuispinis )].

Supplementary morphological characters. Cephalic shield conspicuously granulated visible under the skin; a moderately developed fenestra limited by frontal and lateral ethmoid bones visible under the skin; medial groove of neurocranium very distinct, limited by frontal bones and/or on supraoccipital; posterior cranial fontanel of moderate size, long and narrow; fenestra limited by supraoccipital, pterotic and sphenotic absent; fossa limited by pterotic, supracleithrum and extrascapular moderately large; epioccipital invading dorsal portion of cephalic shield; occipital process triangular, moderately long and wide, progressively narrower toward its posterior part; anterior and median nuchal plates fused and indistinct, forming a structure of semi-lunar aspect; vomerine tooth plates absent; accessory tooth plates well developed oval shaped, with conical teeth; maxillary barbel fleshy and cylindrical; two pairs of mental barbels; base of adipose fin moderately long, about half the length of anal-fin base; lateral line not bifurcated at caudal region, reaching base of caudal-fin upper lobe; cleithrum wide, with second dorsal process on its upper portion; posterior cleithral process moderately long and distinct from second dorsal process of cleithrum.

Remarks. Carlarius is established to accommodate all ariid species from the occidental portion of the African continent that in previous classifications were included in Arius (Fowler, 1936; Taylor, 1986, 1990; Burgess, 1989; Daget, 1992) and were recognized by Marceniuk (2003) as a monophyletic lineage. They can be easily differentiated from all members of Arius by having the lateral line not bifurcated at caudal region, reaching caudal-fin upper lobe and the epioccipital bone exposed on the dorsal part of the cranium (see also diagnosis of the genus). C. gigas (Boulenger, 1911) was not examined and its inclusion in the genus is based on diagnostic characters from the literature.

Distribution and habitat. Western Africa, brackish and fresh waters.

Etymology. The first part of the generic name honors Dr. Carl Ferraris, Research Associate at the California Academy of Sciences for his contribution to the knowledge of Siluriformes fishes and continuous support and encouragement throughout the development of this work. The second part is from the frequently used generic name Arius .