2009年4月6日 星期一

巴西阿拉圭亞-投肯廷斯河系兩個兔脂鯉屬新種

文獻來源: Garavello JC, Santos GM. 2009. Two new species of Leporinus Agassiz, 1829 from Araguaia-Tocantins system, Amazon basin, Brazil (Ostariophysi, Anostomidae). Brazilian Journal of Biology 69 (1): 109-116. [全文下載]

Abstract
Two new species of genus Leporinus from the Araguaia-Tocantins system, Amazon, Brazil, are described. Leporinus unitaeniatus n. sp. is distinguished from the remaining species of this genus by the presence of a conspicuous longitudinal dark brown bar along the lateral line on the flanks, and Leporinus geminis n. sp. is distinguished by an inconspicuous dark bar combined with three large and vertically elongated brown blotches on the trunk; the first on the dorsal fin region, the second anterior to the adipose fin and the third on the caudal peduncle. Both are medium-sized species of the genus (up to 150 mm SL) and share the following combination of meristic characters: 4 teeth on each premaxillary and dentary; 40-43 scales in the lateral line, 6/I/5 scales on the transversal line, and 16 series of scales around the caudal peduncle. L. unitaeniatus n. sp. has a sub-terminal mouth and tooth series formed by incisive-like elongated teeth frontally turned and with only a straight cutting edge decreasing in size like the steps of stairs from the teeth pair of symphysis. Leporinus geminis n. sp. has a sub-inferior mouth and the tooth series shaped by large incisive-like teeth forming an arched cutting edge, decreasing in size from the symphysal pair of teeth.

圖片連結: 雷魚圖鑑 (此圖並非L. unitaeniatusL. geminis, 只是一個在斑紋上較近似的種類)