Polypterus, 2006

Otero, Olga, Likius, Andossa, Vignaud, Patrick & Brunet, Michel, 2006, A new polypterid fish: Polypterus faraou sp. nov. (Cladistia, Polypteridae) from the Late Miocene, Toros-Menalla, Chad, Zoological Journal of the Linnean Society 146 (2), pp. 227-237 : 228

POLYPTERUS FARAOU SP. NOV.

Derivation of name. In Chadian Arabian, faraou means flattened. The name is given in reference to the dorso-ventrally depressed head of the fish.

Type specimen. TM 090-001-039, housed in the Centre National d’Appui à la Recherche ( CNAR, N’Djamena, Chad).

Diagnosis. A Polypterus species characterized by: depressed head (as in P. weeksii and P. endlicheri only), head length approximately 20% of body length (less than 20% in other Polypterus species except P. ansorgii , P. bichir and P. endlicheri ) and head width at the level of the preoperculum reaches 70% of its length (more than in any other Polypterus species); opening of the lateral line on the nasal 3 close to its posterior border (as in P. bichir and P. endlicheri , whereas it is central in other species); large and rounded snout, shorter than the interorbital distance (as in most Polypterus species except P. bichir and P. palmas the snout of which is longer than the interorbital distance); superolateral position of the orbit (as in P. ansorgii , P. weeksii , P. endlicheri and P. bichir , whereas the orbit is lateral in P. delhezi , P. ornatipinnis , P. senegalus , P. retropinnis and P. palmas ); orbit length around the half the interorbital space (as in P. bichir katangae and possibly in P. teugelsi , whereas it is more than 60% in P. ansorgii , and less than 45% in the other species) and orbit smaller than suboperculum width (as in P. bichir and P. endlicheri only); prognathus lower jaw (as in P. bichir and P. endlicheri only); at least 5–7 prespiracular bones (the number of prespiracular bones is possibly equal to or above seven only in P. weeksii , in P. bichir bichir and in P. endlicheri congicus ); deep body with approximately 23 transversal scales, 58–60 scale rows, and 14 predorsal scales (such body shape exists elsewhere only in P. ansorgii , P. bichir and P. endlicheri ); 15 finlets with successive pinnules of the finlets overlapping the base of the following one (such dorsal fin mophology elsewhere only in P. ansorgii , P. bichir and P. endlicheri congicus ); grooved lateral line scales with notched posterior margins (as in P. ansorgii , P. bichir and P. endlicheri only).

The holotype is 590 mm in standard length. Such dimensions are also reached in P. bichir and P. endlicheri only.

Occurrence. Anthracotheriid Unit of Toros-Menalla, Late Miocene of Chad.