浙江猫蛛科一新种：蜘蛛目

在浙江三门发现猫蛛科一新种,暂归人哈猫蛛属,定名为三门哈猫蛛Hamataliwa sanmenensis sp.nov.本新种与三突哈猫蛛H.tricuspidata相近似,但有明显区别。本属为我国新纪录属。     

中国猫蛛属一新种(蜘蛛目:猫蛛科)

记述中国湖南省猫蛛科Oxyopidac猫蛛属Oxyopes 1新种：壶瓶猫蛛Oxyopes hupingensis sp.nov.。新种不同于本属内其它种。新种与Oxyppes daksina Sherriffs,1955略相似,两者的纳精囊都处于外雌器的中线位置上,但新种在如下几方面不同于后者：交媾腔大,葫芦状;纳精囊从内向外,从后向前扭曲成“U”形;两纳精囊彼此靠近。模式标本保存于湖南师范大学生命科学学院。文中量度单位为mm。     

The lethal and sublethal effects of three pesticides on the striped lynx spider (Oxyopes salticus Hentz)

The striped lynx spider, Oxyopes salticus Hentz, is found in high abundances in agricultural fields where it forages on many agricultural pests. Pesticides are applied to these fields and can therefore impact these natural pest predators. Researchers have examined the effects of a number of pesticides on this spider and other pest predators, but many of these studies only examine how these pesticides affect mortality. More recently, researchers have begun to examine the sublethal effects of these chemicals. We examined both the lethal and sublethal effects of three common pesticides with the active ingredients bifenthrin, carbaryl and malathion. We found that only malathion significantly reduced the post‐exposure lifespan of these spiders; however, each pesticide had sublethal effects on behaviour. Exposure to malathion reduced jumping, likely an important foraging and escape behaviour. Spiders exposed to bifenthrin spent increased time grooming, which can reduce the time spent performing other important behaviours. Finally, spiders that were exposed to carbaryl surprisingly increased their prey capture rate. We show here that pesticides can not only directly affect the lifespan of the striped lynx spider but that each pesticide can cause different sublethal effects that likely impact the survival and ecology of these important pest predators.     

中国猫蛛属三新种(蜘蛛目,猫蛛科)

记述了中国湖南省猫蛛科Oxyopidae猫蛛属Oxyopes 3新种：环缘猫蛛Oxyopes annularis sp.nov.,弓缘猫蛛Oxy-opes arcuatus sp.nov.和带缘猫蛛Oxyopes balteiformis sp.nov.3新种的主要鉴别特征。环缘猫蛛,新种Oxyopes annularis sp．nov．与条纹猫蛛Oxyopes striagntus Song,1991相似,但新种腹部细长,末端特别尖细;外雌器角质化后缘拱起较宽长,呈半圆形,其前缘正中尚有两个小疣突,后者角质化后缘拱起较窄短,呈蛇头状,正中没有成对小疣突。弓形猫蛛,新种Oxyopes arcuatus sp．nov．与尖峰猫蛛Oxyopes jianfeng Song,1991相似,但新种外雌器角质化后缘弯曲呈弓形,近乎半圆,后者条状,近乎平直,仅两侧端稍有弯曲;纳精囊较大,交媾管远端细,弯曲呈圆圈,近端变粗呈漏斗形,后者交媾管粗细均匀,远端平直折向近端。不呈漏斗状。带缘猫蛛,新种Oxyopes balteiformis sp．nov．与细纹猫蛛Oxyopes macilentus L.Koch,1878相似,但新种外雌器角质化后缘呈横向带状,较宽,正中无任何突起结构,后者角质化后缘腹面正中有一个三角形突起,背面观在阴门正中有一个“T”形脊。     

From lynx spiders to cotton: Behaviourally mediated predator effects over four trophic levels

Food web studies often examine density and behaviourally mediated effects of predators on herbivores, but are less likely to assess the plant targeted by the herbivore. We conducted a study that incorporated four trophic levels examining the effect of two generalist predators (damsel bugs, Nabis kinbergii Reuter; and lynx spiders, Oxyopes molarius L. Koch) on damage to cotton bolls caused by green mirids (Creontiades dilutus (Stål)). First we tested whether lynx spiders and damsel bugs could control mirid numbers and cotton boll damage in field cages. We found that in cages containing mirids and only lynx spiders, lynx spiders reduced both mirid numbers and boll damage. However, in cages which contained mirids and both predators (lynx spiders and damsel bugs) only mirid numbers were reduced. To explain the negative effect of damsel bugs on boll damage, we examined the interactions between lynx spiders, damsel bugs and mirids. We found that lynx spiders were better mirid predators than damsel bugs, and that lynx spiders attacked damsel bugs, but not vice versa. Behaviourally, mirids responded to increasing predator pressure regardless of whether the predators were lynx spiders or damsel bugs. However, damsel bugs seemed to alter the behaviour of lynx spiders because in their presence, a higher proportion of lynx spiders moved to the top of the plant, towards the damsel bugs but away from the bolls found lower on the plant. These results suggest that the most likely explanation for the increase in boll damage in the presence of damsel bugs was that lynx spiders moved to the top of the plant in the presence of damsel bugs, which then exposed the bolls lower down on the plant to mirid attack. This work emphasizes the importance of behaviourally mediated effects in food webs extending over four trophic levels.