Murphy John C, Charles Stevland P, Lehtinen Richard M, Koeller Krista L
Science & Education, Field Museum of Natural History, 1400 S. Lake Shore Drive, Chicago, IL 60605, USA.
Zootaxa. 2013;3718:561-74. doi: 10.11646/zootaxa.3718.6.4.
Currently, two snake species of the genus Leptophis occur in Trinidad and Tobago. One, L. stimsoni, is endemic to Trinidad's Northern Range and known from relatively few specimens. The second is the diurnal, arboreal, brightly colored parrot snake Leptophis coeruleodorsus Oliver. It was originally described based on 23 specimens from Trinidad, Tobago, and four locations in northern Venezuela but remains poorly known. It was later assigned as a subspecies of Leptophis ahaetulla; a widespread, polytypic species. Here we compare 11 specimens of the L. ahaetulla Group using DNA sequences from two mitochondrial genes (cytochrome b and 16S, 1,383 bp total) from island and mainland populations, report on the variation in the morphology of 54 museum specimens of Leptophis a. coeruleodorsus; describe the previously undescribed holotype of L. coeruleodorsus Oliver, and restrict its type locality. Additionally, we describe a new species of Leptophis from the island of Tobago that can be distinguished from L. coeruleodorsus on the basis of snout shape, upper labial architecture, elongated prefrontal scales, and ventral scale counts. The new Leptophis raises the number of endemic Tobago amphibians and reptiles to 11 taxa.
目前，特立尼达和多巴哥有两种细蛇属的蛇类。一种是史氏细蛇，它是特立尼达北部山脉的特有物种，已知标本相对较少。另一种是日行性、树栖、色彩鲜艳的鹦鹉蛇奥利弗氏细蛇。它最初是根据来自特立尼达、多巴哥以及委内瑞拉北部四个地点的23个标本描述的，但人们对它仍然知之甚少。后来它被归为细蛇的一个亚种；细蛇是一个分布广泛、多型的物种。在这里，我们使用来自岛屿和大陆种群的两个线粒体基因（细胞色素b和16S，总共1383个碱基对）的DNA序列，比较了11个细蛇种群的标本，报告了54个奥利弗氏细蛇博物馆标本的形态变异情况；描述了此前未描述过的奥利弗氏细蛇的模式标本，并限定了其模式产地。此外，我们还描述了一种来自多巴哥岛的新细蛇物种，它可以根据吻部形状、上唇结构、延长的额前鳞片和腹鳞数量与奥利弗氏细蛇区分开来。这种新的细蛇使多巴哥特有的两栖动物和爬行动物种类增加到了11种。
