Merodoras, Higuchi, Horácio, Birindelli, José L. O., Sousa, Leandro M. & Britski, Heraldo A., 2007

Higuchi, Horácio, Birindelli, José L. O., Sousa, Leandro M. & Britski, Heraldo A., 2007, Merodoras nheco, new genus and species from Rio Paraguay basin, Brazil (Siluriformes, Doradidae), and nomination of the new subfamily Astrodoradinae, Zootaxa 1446, pp. 31-42 : 33

Merodoras new genus

Type species. — Merodoras nheco new species.

Diagnosis. — Merodoras is diagnosed from all other doradids by having midlateral plates with medial thorns directed ventrally in adults, and from all doradids except Physopyxis cristata by having an incomplete lateral line. Merodoras also is diagnosed by the unique combination of the following characteristics: pectoral girdle entirely exposed ventrally, with the opening for the arrector ventralis inferior reduced to a small fossae on anterior edge of coracoid; caudal fin truncate; dorsal-fin spine smooth, without serrae; lacrimal serrated; lateral ethmoid serrated.

Comparisons. — Merodoras can be distinguished from Anadoras , Scorpiodoras , Astrodoras and Hypodoras by the pectoral girdle entirely exposed ventrally, with the opening for the arrector ventralis inferior reduced to a small fossae on anterior edge of coracoid; Merodoras is further distinguished from Scorpiodoras and Astrodoras by having dorsal-fin spine smooth (vs. serrated anteriorly), anterior cranial fontanel oval (vs. elongate), mesethmoid straight in dorsal profile (vs. mesethmoid concave with a median dorsal crest), and gas bladder simple (vs. gas bladder with terminal diverticulum); and from Astrodoras and Hypodoras by having procurrent rays not modified as plates (vs. procurrent rays modified as plates that frame caudal peduncle). Merodoras is further distinguished from Hypodoras by the absence of a pre-adipose plate (vs. present). Merodoras is yet distinguished from Anadoras by having lacrimal serrated (vs. lacrimal smooth) and from Amblydoras and Physopyxis by the smooth dorsal-fin spine (vs. serrated at the proximal portion on the anterior face) and smooth infraorbitals (vs. serrated). It is also distinguished from Physopyxis by presence of anterior nuchal plate (vs. anterior nuchal plate absent), tip of coracoid process extending posteriorly beyond tip of postcleithral process (vs. posterior tip of coracoid process falling short of tip of postcleithral process).

Etymology. — From the Greek meros (= part, portion), in reference to the incomplete lateral line, plus the suffix – doras , as traditionally applied to genera in this family. Gender masculine.