TL;DR: This investigation allowed us to integrate methodologies into an efficient, consistent, and more effective general methodological workflow for estimating species boundaries within the mygalomorph spider genus Aphonopelma.
TL;DR: The use of numerous species delimitation methods, in concert, provide an effective approach to dissecting species boundaries in this spider group, and seem to provide strong evidence for a number of nominal, previously undiscovered, and cryptic species.
Abstract: Background
The primary objective of this study is to reconstruct the phylogeny of the hentzi species group and sister species in the North American tarantula genus, Aphonopelma, using a set of mitochondrial DNA markers that include the animal “barcoding gene”. An mtDNA genealogy is used to consider questions regarding species boundary delimitation and to evaluate timing of divergence to infer historical biogeographic events that played a role in shaping the present-day diversity and distribution. We aimed to identify potential refugial locations, directionality of range expansion, and test whether A. hentzi post-glacial expansion fit a predicted time frame.
TL;DR: A pair of tarantulas discovered from an unsampled region in the Sierra de Bacadéhuachi (the westernmost range of the Sierra Madre Occidental) in northeastern Sonora was found to be closely related to four species from the Madrean "Sky Islands" in Arizona and New Mexico.
Abstract: The tarantula spider genus Aphonopelma Pocock, 1901 has received considerable attention in recent years but the group's diversity remains poorly understood in Mexico, particularly in the pine-oak woodlands of the Sierra Madre Occidental and associated Madrean "Sky Islands". A pair of tarantulas discovered from an unsampled region in the Sierra de Bacadehuachi (the westernmost range of the Sierra Madre Occidental) in northeastern Sonora was found to be closely related to four species from the Madrean "Sky Islands" in Arizona and New Mexico. An integrative approach for delimiting species (incorporating data from molecular phylogenetics, morphology, distributions, and breeding periods) suggests that the specimens from Sierra de Bacadehuachi belong to an undescribed species that is herein named Aphonopelma bacadehuachi sp. nov. This new species adds to our knowledge of an increasingly diverse assemblage of Aphonopelma from the Madrean Pine-Oak Woodlands Hotspot. Collaborations between Mexican and American researchers are needed to accelerate discovery and description of the group's remaining diversity, particularly in light of the many threats facing the ecoregion including habitat degradation and climate change.
TL;DR: This work employed five different approaches for delimiting species in a group of closely related tarantulas from the Mojave Desert in the southwestern United States, demonstrating that the taxonomy of these spiders as presently defined underestimates actual species-level diversity and the group is in need of revision.
TL;DR: Overall movement of males was in all directions and randomness could not be excluded as a factor, and individual males moved relatively large distances, up to 1300 m, and significant directedness was only found in three individuals.
Abstract: This study was designed to gain insight into the ''migratory'' life history component of the male brown tarantula, Aphonopelma hentzi (Girard 1854), and to determine if radio telemetry could successfully answer questions regarding the ecology of theraphosids. Tarantulas were equipped with radio transmitters and movement monitored using an antenna and radio receiver. Overall movement of males was in all directions and randomness could not be excluded as a factor. Individual males moved relatively large distances, up to 1300 m, and significant directedness was only found in three individuals. In addition, notes on habitat, ecology and behavior are presented.