八种蜘蛛毒腺的形态学观察

Morphological Observation of Venom Glands in Eight Species of Spiders

为了解原蛛类和新蛛类蜘蛛毒腺的形态学差异,为今后蜘蛛毒腺的进化和形态研究提供参考。本实验选择了原蛛类和新蛛类各四种蜘蛛,对其毒腺的大小、位置及其外部形态特征和内部结构进行观察和比较研究。观察发现新蛛类的毒腺分布在头胸部,原蛛类的毒腺则分布在螯基中;原蛛类前端有细长的毒液导管,与螯牙相连,而尾端呈锥形向后延伸,逐渐变细,形成索状结构,可能是毒腺导管或神经束的韧带;新蛛类有一条导管,从前端伸出,深入螯基并与螯牙相连,而远端钝圆,没有索状结构。毒腺的大小和形态存在显著差异;观察毒腺的内部结构显示:原蛛类的腺腔数目较多且紧密,新蛛类的腺腔较少而疏松。这一结果在一定程度上表明了蜘蛛毒腺的位置变化和形态结构可能与蜘蛛毒腺的进化存在着一定关系。

This experiment aims at understanding the morphological differences between the venom glands of the Mygalomorphae and Araneomorphae,and to provide a reference for future study of the evolution and morphology of spider venom glands.In this experiment,four species of Mygalomorphae and four spiders of Araneomorphae were selected for observation and comparison of the size,location,external morphological characteristics,and internal structure of their venom glands.The results showed that the venom glands of the Araneomorphae are usually located in the prosoma and are distributed symmetrically,while those of the Mygalomorphae are usually located in the chelicera;they have ducts in the apex and extension from the prosoma or chelicera to the fang,The free ends of the former are blunt and round without ducts,and the venom glands of the latter have tapered ends that are elongated and tapered back,creating a cord-like structure;Different species of spider venom glands vary in size and shape;Observation of the internal structure of the venom gland showed that the glandular cavities of the Mygalomorphae were more numerous and compact,and the glandular cavities of the Araneomorphae were less and loose.To a certain extent,this result indicates that the position change and morphological structure of spider venom glands may be related to the evolution of spider venom glands.