游蛇科8种蛇的鳞片显微皮纹结构观察

Microdermatoglyphic Structures of Eight Species of Snakes(Colubridae)

游蛇科8种蛇,分别为云南沾益采集的棕网腹链蛇(Hebius johannis),云南铜壁关采集的卡西腹链蛇(H.khasiensis)、八线腹链蛇(H.octolineatum)、双带腹链蛇(H.parallela)、八莫过树蛇(Dendrelaphis subocularis),云南澜沧采集的大眼斜鳞蛇(Pseudoxenodon macrops),云南昆明采集的虎斑颈槽蛇(Rhabdophis tigrinus),云南临沧采集的中国小头蛇(Oligodon chinensis)。于2014年4月对其背鳞显微皮纹结构进行扫描电镜观察,8种蛇每种使用1个个体,每个个体分别从蛇体的前、中、近尾部各采集3枚鳞片,共观察9枚鳞片。低倍下观察到鳞棱,高倍下观察到纵行小棱、条索、横纹、小孔结构,这些结构存在种间差异。八莫过树蛇和中国小头蛇无鳞棱,但是其余6种蛇鳞棱十分明显;大眼斜鳞蛇的纵行小棱短于100μm,其余7种蛇的纵行小棱均长于100μm;仅八莫过树蛇和双带腹链蛇背鳞上有明显的条索结构;八莫过树蛇的横纹为平缓波纹,其余7种蛇的横纹为"U"形波纹;小孔的形状、排列位置在种间变化较大,小孔的密集程度以八莫过树蛇、大眼斜鳞蛇、虎斑颈槽蛇较高。在8种蛇中,八莫过树蛇背鳞的显微皮纹结构最为复杂,可能与其栖息在热带雨林中有关。

Scanning electron microscopy was used to examine the microdermatoglyphic structures of the dorsal scales of eight species of colubridae snakes, which were collected from Yunnan Province（Table 1）. Species are Brown Netted Keelbacks（Hebius johannis）, Khasi Keelbacks（H. khasiensis）, Eight Lined Keelbacks（H. octolineatum）, Boulenger′s Keelbacks（H. parallela）, Bhamo Tree Snakes（Dendrelaphis subocularis）, Big-Eyed Mountain Keelbacks（Pseudoxenodon macrops）, Tiger Groove-necked Keelbacks（Rhabdophis tigrinus）, and Chinese Kukri Snakes（Oligodon chinensis）, and all the specimens are preserved in the zoological museum of southwest forestry university. We chose one individual for each species and examined 3 dorsal scales at neck, back, and rear respectively. Totally, five kinds of microstructures were found on the scales： keel, longitudinal ridge, thin ridge, vertical stripe, and pore. The characteristics of these microstructures varied among these species（Table 2）. Six species had keeled scales, which were not observed in Bhamo Tree Snake and Chinese Kukri Snake. The longitudinal ridge was longer than 100 μm in 7 speciess, but shorter than 100 μm in Big-eyed Mountain Keelback. The thin ridge was only found in Bhamo Tree Snake and Boulenger′s Keelback. The vertical stripe showed U-shape in 7 snakes but wave-shape in Bhamo Tree Snake. The position and structure of the pores differed significantly among these species, but more densely distributed in Bhamo Tree Snake, Big-eyed Mountain Keelback, and Tiger Groove-necked Keel back. The microdermatoglyphic structures of Bhamo Tree Snake were the most complex（Fig. 1） that might be due to the humid tropical rainforest they lived in.