Comparative Population Genomic Diversity and Differentiation in Trapdoor Spiders and Relatives (Araneae, Mygalomorphae).

Although patterns of population genomic variation are well-studied in animals, there remains room for studies that focus on non-model taxa with unique biologies. Here we characterise and attempt to explain such patterns in mygalomorph spiders, which are generally sedentary, often occur as spatially clustered demes and show remarkable longevity. Genome-wide single nucleotide polymorphism (SNP) data were collected for 500 individuals across a phylogenetically representative sample of taxa.

Broken Ring Speciation in California Mygalomorph Spiders (Nemesiidae, ).

AbstractIdealized ring species, with approximately continuous gene flow around a geographic barrier but singular reproductive isolation at a ring terminus, are rare in nature. A broken ring species model preserves the geographic setting and fundamental features of an idealized model but accommodates varying degrees of gene flow restriction over complex landscapes through evolutionary time. Here we examine broken ring species dynamics in spiders, which, like the classic ring species salamanders, are distributed around the Central Valley of California.

Species delimitation, biogeography, and natural history of dwarf funnel web spiders (Mygalomorphae, Hexurellidae, ) from the United States / Mexico borderlands.

The rarely encountered spider genus Gertsch & Platnick, 1979 includes some of the smallest mygalomorph spiders in the world, with four poorly known taxa from central and southeastern montane Arizona, southern California, and northern Baja California Norte. At time of description the genus was known from fewer than 20 individuals, with sparse natural history information suggesting a vagrant, web-building, litter-dwelling natural history. Here the first published taxonomic and natural history information for this taxon is provided in more than 50 years, working from extensive new geographic sampling, consideration of male and female morphology, and sequence capture-based nuclear phylogenomics and mitogenomics.

Five new species of Stenochrus (Schizomida: Hubbardiidae) from Oaxaca, Mexico.

The North American genus Stenochrus is represented by 22 species distributed mainly in Mexico, Central America and the U.S.A.

Taxonomic revision of the genus Mayazomus Reddell & Cokendolpher, 1995 (Schizomida: Hubbardiidae), with description of five new species from Chiapas, Mexico.

The genus Mayazomus currently contains two species from southeastern Mexico. It was originally characterized by a strongly elongated pedipalp trochanter, united in its entire width to the femur; the patella strongly curved; the tibia with a large mesal apophysis opposable to tarsus; the spermathecae with two pairs of thin lobes subequal in length; and the presence of four or more setae on tergite II. In the present contribution, the species of the genus Mayazomus are revised and new diagnostic characters for the genus are proposed, including the correction that the female flagellum bears three rather than two annuli.