属模巨齿蛉末龄幼虫的打洞行为研究

The burrowing behavior of the final-instar larva of Acanthacorydalis asiatica(West-Wood,1884)(Megaloptera:Corydalidae)

本文以属模巨齿蛉为例,首次研究了广翅目末龄幼虫化蛹前的打洞行为及洞穴类型。试验通过昼夜录像等手段,较为详细地分析了属模巨齿蛉末龄幼虫的打洞行为,并对洞穴进行解剖、测量和拍照,获得了洞穴的相应数据和类型。研究结果表明,属模巨齿蛉末龄幼虫的打洞行为主要包括寻找洞址、用大颚衔土建洞、封洞等过程,主要在19∶00-次日12∶00时间段打洞,选择有遮蔽物的地方作为洞址;在选址或打洞的过程中,有时会出现多头幼虫争夺洞址的现象;打洞时,幼虫主要是用大颚衔土,衔土频率为1-12次/min,或用整个头部前端铲土,通过腹部肌肉伸缩为头部挖土提供动力;幼虫在打洞期间会有不同的休息时间,建造一个洞穴大约需要累计时间120-250 min,一次连续打洞的时间为37 s-17 min;洞穴类型分为封口洞穴和开口洞穴2大类,其中封口洞穴有5种类型,开口洞穴有2种类型;洞穴深度为3.0-7.5 cm,洞内最大直径为2.5-5.0 cm;幼虫在预蛹期间还可以从洞穴中爬出来到水中取食,之后再返回洞中。

This paper reported firstly the burrowing behavior and cave types of the final-instar larval Megaloptera before pupation,taking Acanthacorydalis asiatica（West-Wood,1884） for example.By videoing for day and night and other means,the test analyzed in detail the burrowing behavior of the final-instar larva of A.asiatica,and obtained the corresponding data and types of the caves by dissecting,measuring and photographing the dry caves.The results showed that the burrow behavior of A.asiatica included finding the burrow site,building the cave by carrying the sand and earth with mandibles,and sealing the cave.The larva usually chose shelters as burrow site and burrowed mainly in the 19 ∶ 00 to 12 ∶ 00 of the next day.In the course of siting or burrowing,sometimes some larvae would compete for the cave sites.When burrowing,the larva carried the sand and earth by mandibles with a frequency of 1-12 time（s）/min,or shoveled the sand and earth with the entire head,and the abdomen provided the head power to shovel by stretching the muscles.The larva would rest for different time during the burrowing,and need the accumulating time of about 120-250 min for borrowing a whole cave,and the time of continuous borrowing with 37 s-17 min.The cave types were divided into sealing-mouth caves with 5 types and opening-mouth caves with 2 types.The depth of cave was 3.0-7.5 cm and themaximum diameter of cave was 2.5-5.0 cm.The larva during the prepupal period could emerge from the cave and go into the water to feed,and then return to the cave.