Archive for the ‘Spider News in North America’ Category


Great Article not relevant to North America but wonderful to the Americas in general.

 

Abstract

Eight new species of Charinus Simon, 1892 are described for the Brazilian Amazon, from the states of Pará (C. bichuetteae sp. n., C. bonaldoi sp. n., C. carajas sp. n., C. ferreus sp. n., C.guto sp. n. and C. orientalis sp. n.) and Amazonas (Charinus brescoviti sp. n. and C. ricardoi sp. n.). All new species can be differentiated from the other species of the genus by the number of pseudo-articles in basitibia IV, the presence/absence of median eyes, and the shape of the female gonopod. Brazil now becomes the country with the largest diversity of Amblypygi in the world, with 25 known species. Half of the new species described here have a high degree of endangerment: C. bichuetteae sp. n. is threatened by the flood caused by the hydroelectric dam of Belo Monte, and C. carajas sp. n., C. ferreus sp. n. and C. orientalis sp. n. are endangered by the iron mining in Carajás municipality and surroundings. The Charinus species here described are endemic to the Amazon Region, so in order to assure their preservation, it is strongly recommended a special care with their habitats (type localities) which are facing increasing rates of destruction and deforestation.

journal.pone.0148277.g001

PLOS ONE:  URL @ http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0148277

johnny-cash-tarantula-2 (1)

Abstract

This systematic study documents the taxonomy, diversity, and distribution of the tarantula spider genusAphonopelma Pocock, 1901 within the United States. By employing phylogenomic, morphological, and geospatial data, we evaluated all 55 nominal species in the United States to examine the evolutionary history of Aphonopelma and the group’s taxonomy by implementing an integrative approach to species delimitation. Based on our analyses, we now recognize only 29 distinct species in the United States. We propose 33 new synonymies (A. apacheum, A. minchi, A. rothi, A. schmidti, A. stahnkei = A. chalcodes; A.arnoldi = A. armada; A. behlei, A. vogelae = A. marxi; A. breenei = A. anax; A. chambersi, A. clarum, A.cryptethum, A. sandersoni, A. sullivani = A. eutylenum; A. clarki, A. coloradanum, A. echinum, A. gurleyi, A.harlingenum, A. odelli, A. waconum, A. wichitanum = A. hentzi; A. heterops = A. moderatum; A. jungi, A.punzoi = A. vorhiesi; A. brunnius, A. chamberlini, A. iviei, A. lithodomum, A. smithi, A. zionis = A. iodius; A.phanum, A. reversum = A. steindachneri), 14 new species (A. atomicumsp. n., A. catalinasp. n., A.chiricahuasp. n., A. icenogleisp. n., A. johnnycashisp. n., A. maderasp. n., A. marekisp. n., A. moellendorfisp. n., A. parvumsp. n., A. peloncillosp. n., A. prenticeisp. n., A. saguarosp. n., A. superstitionensesp. n., and A. xwalxwalsp. n.), and seven nomina dubia (A. baergi, A. cratium, A. hollyi, A. mordax, A. radinum, A.rusticum, A. texense). Our proposed species tree based on Anchored Enrichment data delimits five major lineages: a monotypic group confined to California, a western group, an eastern group, a group primarily distributed in high-elevation areas, and a group that comprises several miniaturized species. Multiple species are distributed throughout two biodiversity hotspots in the United States (i.e., California Floristic Province and Madrean Pine-Oak Woodlands). Keys are provided for identification of both males and females. By conducting the most comprehensive sampling of a single theraphosid genus to date, this research significantly broadens the scope of prior molecular and morphological investigations, finally bringing a modern understanding of species delimitation in this dynamic and charismatic group of spiders.

Awesome …

URL http://zookeys.pensoft.net/articles.php?id=6264

See also the National Geographic article at http://news.nationalgeographic.com/2016/02/160204-animals-spiders-tarantulas-science-nation/

LiveScience review at http://www.livescience.com/53616-tarantula-named-for-johnny-cash.html

Abstract1-s2.0-S1055790315002043-fx1

Camel spiders (Solifugae) are a diverse but poorly studied order of arachnids. No robust phylogenetic analysis has ever been carried out for the order or for any family within the Solifugae. We present a molecular phylogenetic analysis of the endemic North American family Eremobatidae Kraepelin, 1899, the first such analysis of a family of Solifugae. We use a multi-locus exemplar approach using DNA sequences from partial nuclear (28S rDNA and Histone H3) and mitochondrial (16S rRNA and Cytochrome c Oxidase I) gene loci for 81 ingroup exemplars representing all genera of Eremobatidae and most species groups within the genera Eremobates Banks, 1900, Eremochelis Roewer, 1934, andHemerotrecha Banks, 1903. Maximum Likelihood and two Bayesian analyses consistently recovered the monophyly of Eremobatidae, Eremorhax Roewer, 1934 andEremothera Muma, 1951 along with a group comprising all subfamily Eremobatinae Kraepelin, 1901 exemplars except Horribates bantai Muma, 1989 and a group comprising all Eremocosta Roewer, 1934 exemplars except Eremocosta acuitalpanensis (Vasquez and Gavin, 2000). The subfamily Therobatinae Muma, 1951 and the genera Chanbria Muma, 1951, Hemerotrecha, Eremochelis, and Eremobateswere polyphyletic or paraphyletic. Only the banksi group of Hemerotrecha was monophyletic; the other species groups recognized within Eremobates, Eremochelis, and Hemerotrecha were paraphyletic or polyphyletic. We found no support for the monophyly of the subfamily Therobatinae. A time-calibrated phylogeny dated the most recent common ancestor of extant eremobatids to the late Eocene to early Miocene, with a mean estimate in the late Oligocene (32.2 Ma)

Authors

Link http://www.sciencedirect.com/science/article/pii/S1055790315002043

JBI_large

Abstract

Aim

Phylogeographical studies in the Mojave and Sonoran deserts often find genetic discontinuities that pre-date the Pleistocene. A recent synthesis of phylogeographical data, called the Mojave Assembly Model, provides a hypothesis for the historical assembly of these desert biotas but does not adequately capture the complexity of pre-Pleistocene vicariance events. We tested this model and assessed pre-Pleistocene divergences by exploring the phylogeography of theAphonopelma mojave group, which is composed of turret-building tarantula species from the Mojave and Sonoran deserts.

Location

Mojave and Sonoran deserts, south-western USA.

Methods

We augmented the sampling from a previous study by sequencing mitochondrial DNA (COI) from new material of the A. mojave group. We used phylogenetic and network analyses to identify clades and a molecular clock and lineages-through-time plots (LTT plots) to explore the timing and tempo of diversification. We tested for demographic expansion using neutrality tests and mismatch distributions. Species distribution models (SDMs) were constructed to compare current suitable habitat to that at the Last Glacial Maximum (LGM).

Results

Phylogenetic, network and molecular-clock analyses identified six major clades that probably diverged during the late Miocene. The rate of diversification appears to have slowed during the Pliocene. Most clades exhibit signals of recent demographic expansion. SDMs predicted that suitable habitat shifted south and to lower elevations during the LGM.

Main conclusions

Phylogeographical analyses suggest that the A. mojave group experienced a burst of diversification in the late Miocene, followed by population expansions during the Pleistocene. Six major clades with origins in the late Miocene cannot be adequately explained by the Mojave Assembly Model. We propose the novel hypothesis that Miocene extensional tectonics caused populations to diverge in allopatry by producing low-elevation habitat barriers. Geological models, such as kinematic reconstructions, provide an ideal but underutilized framework for testing biogeographical hypotheses in these deserts and the wider Basin and Range Province.

Online URL Source http://onlinelibrary.wiley.com/enhanced/doi/10.1111/jbi.12494/

See credits and all those involved in this segment for this trip and my colleague Kari McWest  for the Power Point.

http://research.amnh.org/users/lorenzo/PPT/Chihuahua_2005.htm

 

Thank you Cesar for the picture in facebook and using it at UNAM.

I’m on the left, Oscar Francke and David Sissom

Lab

Random pictures from 2010 in Amarillo Texas:

T hawk 2 T hawk 1Peps

 

Blog title update:  Expanding  into news with general arachnids relevant to North America all in one place.  Mexico and the western states in the U.S. presents various transitions zones and micro habitats and is thus unique in arachnid taxa.

Hope you enjoy the site for educational and regional informations !

Sincerely,

Chad Lee B.Sc. 1995.

Biology and Natural Resource Management.  Texas Certified Applicator

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PrintAbstract

Tarantulas in the North American genus Aphonopelma are poorly known due to their challenging patterns of morphological variation and questionable taxonomy; few specimens can be confidently identified using existing keys or comparisons to original descriptions. In an effort to identify new strategies for resolving what has been characterized as a “taxonomic and nomenclatural nightmare”, we employed five different approaches for delimiting species in a group of closely related tarantulas from the Mojave Desert in the southwestern United States. These methods included the application of single techniques (morphology, DNA barcoding, shared genealogical exclusivity among independent loci, and generalized mixed Yule coalescent) and an integrative approach that incorporates genealogical and ecological information. Results demonstrate that the taxonomy of these spiders as presently defined underestimates actual species-level diversity and the group is in need of revision. The number of species delimited by each approach, however, was variable and we argue that it is this discordance that emphasizes the importance of incorporating multiple lines of evidence into an integrative taxonomic framework that can be used for constructing robust taxonomic hypotheses for Aphonopelma species

URL:  http://www.sciencedirect.com/science/article/pii/S1055790312004101

 

1-s2.0-S1055790313004223-fx1DNA

Abstract

The North American tarantula genus Aphonopelma provides one of the greatest challenges to species delimitation and downstream identification in spiders because traditional morphological characters appear ineffective for evaluating limits of intra- and interspecific variation in the group. We evaluated the efficacy of numerous molecular-based approaches to species delimitation within Aphonopelma based upon the most extensive sampling of theraphosids to date, while also investigating the sensitivity of randomized taxon sampling on the reproducibility of species boundaries. Mitochondrial DNA (cytochrome c oxidase subunit I) sequences were sampled from 682 specimens spanning the genetic, taxonomic, and geographic breadth of the genus within the United States. The effects of random taxon sampling compared traditional Neighbor-Joining with three modern quantitative species delimitation approaches (ABGD, P ID(Liberal), and GMYC). Our findings reveal remarkable consistency and congruence across various approaches and sampling regimes, while highlighting highly divergent outcomes in GMYC. Our 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. Taken alone, these approaches are not particularly useful – especially in the absence of prior knowledge of the focal taxa. Only through the incorporation of multiple lines of evidence, employed in a hypothesis-testing framework, can the identification and delimitation of confident species boundaries be determined. A key point in studying closely related species, and perhaps one of the most important aspects of DNA barcoding, is to combine a sampling strategy that broadly identifies the extent of genetic diversity across the distributions of the species of interest and incorporates previous knowledge into the “species equation” (morphology, molecules, and natural history).

URL:  http://www.sciencedirect.com/science/article/pii/S1055790313004223

journal.pone.0017731.g001brownrelcuse

Abstract:

Most spiders use venom to paralyze their prey and are commonly feared for their potential to cause injury to humans. In North America, one species in particular,Loxosceles reclusa (brown recluse spider, Sicariidae), causes the majority of necrotic wounds induced by the Araneae. However, its distributional limitations are poorly understood and, as a result, medical professionals routinely misdiagnose brown recluse bites outside endemic areas, confusing putative spider bites for other serious conditions. To address the issue of brown recluse distribution, we employ ecological niche modeling to investigate the present and future distributional potential of this species. We delineate range boundaries and demonstrate that under future climate change scenarios, the spider’s distribution may expand northward, invading previously unaffected regions of the USA. At present, the spider’s range is centered in the USA, from Kansas east to Kentucky and from southern Iowa south to Louisiana. Newly influenced areas may include parts of Nebraska, Minnesota, Wisconsin, Michigan, South Dakota, Ohio, and Pennsylvania. These results illustrate a potential negative consequence of climate change on humans and will aid medical professionals in proper bite identification/treatment, potentially reducing bite misdiagnoses.

Citation: Saupe EE, Papes M, Selden PA, Vetter RS (2011) Tracking a Medically Important Spider: Climate Change, Ecological Niche Modeling, and the Brown Recluse (Loxosceles reclusa). PLoS ONE 6(3): e17731. doi:10.1371/journal.pone.0017731

Online@http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0017731