Yale-NUS College, 10 College Avenue West #01-101, Singapore 138609, Singapore.
Yale-NUS College, 10 College Avenue West #01-101, Singapore 138609, Singapore; National University of Singapore, Department of Biological Sciences, Singapore.
Mol Phylogenet Evol. 2018 Aug;125:213-219. doi: 10.1016/j.ympev.2018.03.035. Epub 2018 Apr 7.
Psechrids are an enigmatic family of S.E. Asian spiders. This small family builds sheet webs and even orb webs, yet unlike other orb weavers, its putative relatives are largely cursorial lycosoids - a superfamily of approximately seven spider families related to wolf spiders. The orb web was invented at least twice: first in a very ancient event, and then second, within this clade of wolf-like spiders that reinvented this ability. Exactly how the spiders modified their silks, anatomy, and behaviors to accomplish this transition requires that we identify their precise evolutionary origins - yet, thus far, molecular phylogenies show poor support and considerable disagreement. Using phylogenomic methods based on whole body transcriptomes for psechrids and their putative relatives, we have recovered a well-supported phylogeny that places the Psechridae sister to the Ctenidae - a family of mostly cursorial habits but that, as with all psechrids, retains some cribellate species. Although this position reinforces the prevailing view that orb weaving in psechrids is largely a consequence of convergence, it is still possible that some components of this behavior are retained or resurrected in common with more distant true orb weaving ancestors.
拟平腹蛛科是亚洲东南部一个神秘的蜘蛛家族。这个小家族会建造片网甚至圆网，但与其他圆蛛不同的是，它的近亲大多是行动迅速的狼蛛类——一个与狼蛛有关的大约七个蜘蛛家族的超家族。圆网至少被发明了两次：第一次是在一个非常古老的事件中，然后第二次是在这个类似狼的蜘蛛分支中重新发明了这种能力。蜘蛛如何改变它们的丝腺、解剖结构和行为来完成这种转变，这需要我们确定它们的确切进化起源——然而，到目前为止，分子系统发育显示出支持不足和相当大的分歧。我们使用基于整个转录组的系统基因组学方法来研究拟平腹蛛及其可能的近亲，我们已经重建了一个支持度很高的系统发育树，将拟平腹蛛科放在栉足蛛科旁边——栉足蛛科大多是行动迅速的习性，但与所有拟平腹蛛一样，它保留了一些具纺器的物种。虽然这个位置加强了圆网织网在拟平腹蛛中主要是趋同进化的观点，但仍有可能某些行为的成分与更遥远的真正圆网织网祖先共同保留或复活。
