With 30 species and a natural distribution in North America, 28 confined to Mexico, Physocyclus Simon 1893 is the most diverse genus within the pholcid spider subfamily Arteminae. This paper provides the first phylogenetic test of the genus's monophyly through a cladistic analysis of 54 morphological characters using equal and implied weighting. The equally weighted analysis found 12 most parsimonious trees, whereas the analysis with implied weights varying the concavity values (K = 6–10) found five or six most parsimonious trees. The monophyly of the genus Physocyclus is supported by three synaphomorphies: 1) the paired ventral apophysis on the anterior part of the epigynum; 2) the lateral constraints in the middle part of the epigynum; and 3) the arc of the uterus, with a single sclerotized projection on the anterior part. The genus Physocyclus contains two clades treated as species groups: the globosus group, with 11 species, and the dugesi group with 19 species. The species relationships within the globosus group were better resolved than those in the dugesi group. The globosus group has a biogeographical distribution pattern in the Mesoamerican and Mexican Mountain biotic components, whereas the dugesi group has a distribution pattern in the Mesoamerican and Continental Nearctic biotic components. Given the complex biogeography in Mexico, apparently a large-scale vicariant event separated the two major clades within the genus Physocyclus.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.
Vol. 41 • No. 2