Yeargan K V, Quate L W
Department of Entomology, University of Kentucky, 40546-0091, Lexington, KY, USA.
, 16239 Oak Tree Trail, 92064, Poway, CA, USA.
Oecologia. 1996 Apr;106(2):266-271. doi: 10.1007/BF00328607.
Large immature and mature female bolas spiders of the genus Mastophora attract certain male moths by aggressive chemical mimicry of those moth species' sex pheromones. These older spiders capture moths by swinging a "bolas" (i.e., a sticky globule suspended on a thread) at the approaching male moths. Juvenile bolas spiders do not use a bolas, but instead use their first two pairs of legs to grab prey, which our field observations suggested were primarily nematocerous Diptera. Our field experiments over a 2-year period demonstrated that juvenile bolas spiders attract moth flies (Psychodidae), with each species apparently specializing on a particular prey species. In three experiments, sticky traps containing young Mastophora phrynosoma spiderlings consistently captured significantly more male Psychoda phalaenoides than were captured on traps containing spiderlings of other Mastophora species or no spiderlings (control traps). Results from two of the three experiments suggested that Mastophora hutchinsoni spiderlings attract male Psychoda trinodulosa. Only two of our experiments included Mastophora bisaccata and those produced contrasting results. In the first experiment, M. bisaccata appeared to attract P. phalaenoides, albeit in lower numbers than were captured on traps containing M. phrynosoma. However, in a second experiment the following year, M. bisaccata spiderlings attracted Psychoda satchelli, a species that had not been caught on any traps the previous year. As suggested by a systematist four decades ago, the taxon currently called M. bisaccata may consist of two or more sibling species, which could account for the contrasting results obtained from our two experiments involving M. bisaccata. This is the first reported evidence that, during early developmental stadia before these spiders attract moths, juvenile bolas spiders attract their prey.
大齿猛蛛属的大型未成熟和成熟雌性流星锤蜘蛛，通过对某些蛾类物种性信息素的攻击性化学模拟，来吸引特定的雄性蛾类。这些成熟的蜘蛛通过向靠近的雄性蛾类挥舞一个“流星锤”（即一个悬挂在丝线上的粘性小球）来捕获蛾类。幼年流星锤蜘蛛并不使用流星锤，而是用它们的前两对腿来抓取猎物，我们的野外观察表明，其猎物主要是长角亚目双翅目昆虫。我们在两年时间里进行的野外实验表明，幼年流星锤蜘蛛会吸引蛾蠓（蛾蠓科），每个物种显然都专门捕食一种特定的猎物。在三个实验中，装有幼年弗氏大齿猛蛛的粘性陷阱持续捕获到的雄性法老蛾蠓，明显多于装有其他大齿猛蛛属蜘蛛幼体的陷阱或没有蜘蛛幼体的陷阱（对照陷阱）。三个实验中的两个实验结果表明，哈钦森大齿猛蛛幼体会吸引三瘤蛾蠓雄蛾。我们的实验中只有两个包括了双囊大齿猛蛛，结果却相互矛盾。在第一个实验中，双囊大齿猛蛛似乎能吸引法老蛾蠓，尽管捕获数量比装有弗氏大齿猛蛛的陷阱要少。然而，在次年的第二个实验中，双囊大齿猛蛛幼体吸引了萨氏蛾蠓，该物种在前一年的任何陷阱中都未被捕获。正如一位系统学家在四十年前所指出的，目前被称为双囊大齿猛蛛的分类单元可能由两个或更多的姐妹物种组成，这可以解释我们涉及双囊大齿猛蛛的两个实验所得到的相互矛盾的结果。这是首次有报道证明，在这些蜘蛛吸引蛾类之前的早期发育阶段，幼年流星锤蜘蛛就能吸引它们的猎物。
