Sexual-dimorphism-reversed
Guides
Bothriocyrtum californicum
California trapdoor spider, California cork-lid trapdoor spider
Bothriocyrtum californicum is a cork-lid trapdoor spider endemic to arid regions of the southwestern United States and northwestern Mexico. This mygalomorph spider constructs burrows with a hinged, cork-like door made of soil and silk, which it uses to ambush passing prey. Males are smaller than females, a reversal of typical sexual dimorphism in spiders. The species is notable as the first representative of its genus and family to have its mitochondrial genome sequenced.