A revised classification of the family Dasyatidae (Chondrichthyes: Myliobatiformes) based on new morphological and molecular insights Author Last, Peter R. Author Naylor, Gavin J. P. Author Manjaji-Matsumoto, B. Mabel text Zootaxa 2016 4139 3 345 368 journal article 10.11646/zootaxa.4139.3.2 51358935-98b0-4d89-a47f-e4341171e5b9 1175-5326 262765 DCF4220B-4A73-407C-837C-54DEAE29F435 Genus Brevitrygon gen. nov. Type species Dasyatis javaensis Last & White, 2013 ; newly proposed. Definition. Small dasyatids (adults typically to 23–32 cm DW) characterised by the following: strongly depressed, oval to suboval disc with pectoral-fin apex broadly rounded; snout acutely angular and elongate (1.9–3.6 times combined orbit and spiracle length); eye small and protruding slightly; nasal curtain broadly skirt shaped; mouth medium-sized with 2–4 oral papillae; tail rather short and semi-rigid or filamentous distally (length 1–2.2 times DW), its base broad and strongly or weakly depressed; pelvic fins small to medium-sized, protruding slightly beyond disc; dorsal fold and ventral folds absent (low ridges present in B. walga ); caudal sting close to tail base (distance from pectoral-fin insertion to caudal-sting base 1.4–2 times interspiracular width); denticle band well developed with edge sharply defined, skin on rest of disc naked; median thorns on disc weak, those on tail larger when present; no scapular thorns and rarely denticles on posterior tail; dorsal coloration plain; ventral surface white, disc margin dark edged; posterior tail plain or with pale lateral stripe; marine, Indo– West Pacific. Species . B. heterura (Bleeker, 1852) , B. imbricata (Bloch & Schneider, 1801) , B. javaensis (Last & White, 2013) , and B. walga (Müller & Henle, 1841) . Etymology . Combination of the Latin brevi (short) and Greek trygon (stingray) reflects the short and semirigid tail of all members of the genus. Remarks . Newly erected, morphologically conservative genus with four small species previously placed in Himantura . The taxonomy of this group is very confused and is the subject of a generic review in progress (PL, unpublished). Brevitrygon heterura (Bleeker, 1852) is the correct name of a common Western Pacific species, misidentified as Himantura (= Brevitrygon ) walga (Müller & Henle, 1841) . Brevitrygon walga and B. imbricata (Bloch & Schneider, 1801) are both confined to the Indian Ocean.