The distribution, spatial clustering, and density of trapdoor spiders in two California coastal dune ecosystems

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  The distribution, spatial clustering, and density of trapdoor spiders in two California coastal dune ecosystems Abstract Coastal dune ecosystems support endemic trapdoor spiders, yet population data for these species are limited. We conducted the first coastal dune trapdoor spider population estimation surveys at Moss Landing State Beach (California) and for Aptostichus stephencolberti Bond 2008 at Sunset State Beach using randomly selected 1m 2 quadrats across ~26,000 m 2 per site. Burrow densities were similar between sites (Sunset: 0.287 burrows/m 2 ; Moss: 0.453 burrows/m 2 ), yielding estimated population sizes of ~35,206 and ~30,959 individuals, respectively. However, spatial analyses revealed contrasting patterns of burrow distribution. At Sunset State Beach, burrow presence was strongly associated with vegetation and occurred closer to plants, despite vegetation being randomly distributed. In contrast, no vegetation–burrow association was detected at Moss Landing, alth...

The genus Thrixopelma Schmidt, 1994 from Peru: redescription of the male of T. ockerti Schmidt,1994 (Araneae: Theraphosidae: Theraphosinae), and a new species

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The genus Thrixopelma Schmidt, 1994 from Peru: redescription of the male of T. ockerti Schmidt,1994 (Araneae: Theraphosidae: Theraphosinae), and a new species

Abstract
We redescribe and illustrate the male of Thrixopelma ockerti Schmidt, 1994 presenting the first analysis of keels on the palpal bulb. Additionally, a new species Thrixopelma kimraykawsaki sp. nov. is described and illustrated from Peru, along with data on its natural history. This new species is known from Abancay, department of Apurimac, can be distinguished from other species by having a palpal bulb bearing a tegular heel, a spatu-late embolus with well developed prolateral keels, and the presence of a retrolateral keel. Females are differentiated from other known Thrixopelma species by the shape of the spermathecae and the number of labial cuspules. 

West, Rick.,Fiorella Signorotto, Nelson Ferretti,Juan C. Chaparro,José A. Ochoa,2025). The genus Thrixopelma Schmidt, 1994 from Peru: redescription of the male of T. ockerti Schmidt,1994 (Araneae: Theraphosidae: Theraphosinae), and a new species. Arachnology. 20. 107-114.