西藏自治区发现贡山白环蛇兼记其半阴茎形态及一新色型

Lycodon gongshan Found in Tibet, China, with Description of Hemipenes and a New Color Type

2019年8至9月,在西藏自治区察隅县察瓦龙乡和云南省怒江州泸水市鲁掌镇分别采集到1号和2号白环蛇属(Lycodon)标本。经过形态特征比较和线粒体Cytb基因序列分析,鉴定所采集3号标本均为贡山白环蛇(L. gongshan)。此次在察隅所采集到的贡山白环蛇为西藏自治区蛇类分布新记录种。察隅标本体背以橄榄褐色为主,具不规则黑色窄横纹,腹面为不规则斑纹,为该物种的一个新色型。此外,本文补充了该物种的半阴茎形态描述。

One specimen of Lycodon was collected from Chawalong Town, Zayu County, Tibet Autonomous Region, China during filed work in August and September 2018. The specimen from Zayu was similar to holotype for morphological comparison(Table 2). Analysis of mitochondrial DNA Cyt b sequences revealed that the sample from Zayu cluster with samples from Lushui and Lincang, Yunnan Province. The genetic distance within this clade was limited in 0.004-0.018(Table 3). The specimen from Zayu was more related with specimens from Lushui with a minor distance between 0.004-0.006. Combined with morphological comparison, the Zayu specimen was finally identified as L. gongshan. This was the first record for the species in Tibet Autonomous Region. We also presented description of the hemipenes morphology of L. gongshan for the first time. Hemipenes of L. gongshan near bulbous, covered with small spine;spine on hemipenis larger and keratinized on base;no calyculate zone on top. Hemipenes not bifurcate;sulcus shallow, distinct, without spines;reaches 5 th subcaudals when everted(Fig. 3). Two known body coloration of the species were recorded: rufous with black banded from Lushui and the type locality Gongshan County, Yunnan Province;white with black banded from Panzhihua in Sichuan Province. However, the body of Zayu specimen are olive-brown with black banded, which is reported for the first time.