Archive for the ‘Online Arachnid Publications’ Category


Abstract:
Genus Catalinia, gen. nov. (Scorpiones: Vaejovidae) is described from southern California, USA and Baja California, Mexico. The genus is composed of four species formerly placed inPseudouroctonusCatalinia minima (Kraepelin, 1911), comb. nov. (type species), C. andreas (Gertsch et Soleglad, 1972), comb. nov., C. castanea (Gertsch et Soleglad, 1972), comb. nov., and C. thompsoni, comb. nov. (Gertsch et Soleglad, 1972). Major diagnostic characters of Catalinia include a carapace with a very weak anterior indentation, a very stout metasoma with little or no tapering from segment I to V, and a mating plug with two partial bases. Evidence is presented suggesting that Catalinia is closely related to the “apacheanus” species group of Pseudouroctonus.

Link:  http://www.science.marshall.edu/fet/euscorpius/p2017_251.pdf

We present a mtDNA gene tree of tarantula spiders (Araneae: Mygalomorphae: Theraphosidae) based on the mitochondrial 16S-tRNA (leu)-ND1 gene region as a promising initial molecular hypothesis to clarify the taxonomy of the largest subfamily, Theraphosinae. Many species of this New World subfamily are traded widely as exotic pets, yet few scientific studies on them exist, and the robustness of many supposed taxonomic groupings is debatable. Yet the validity of taxon names and knowledge of their distinctiveness is vital for trade regulation, most notably for the Neotropical genus Brachypelma Simon 1891, which is listed under CITES (Appendix II, see online supplemental material, which is available from the article’s Taylor & Francis Online page at https://doi.org/10.1080/14772000.2017.1346719). The use of molecular markers for tarantula taxonomy has been limited until recently, with most previous studies relying on morphological methods. Our findings, from newly collected molecular data, have several nomenclatural implications, suggesting a need for a rigorous overhaul of Theraphosinae classification at multiple hierarchical levels. Here, we take steps toward a revised classification, favouring division of Theraphosinae into three tribes: the Theraphosini trib. nov., the Hapalopini trib. nov., and the Grammostolini trib. nov. We also make conservation recommendations for two non-monophyletic genera. Firstly, we recover Aphonopelma Pocock 1901 as polyphyletic, finding that the large radiation into the USA and Mexico is taxonomically distinct from at least three other lineages distributed throughout Central America, one of which includes the type species of the genus. Secondly, and importantly for conservation, we find diphyly in the CITES listed genus Brachypelma Simon 1891, where our data strongly favour a division into two distinct smaller genera. We consider only the lineage with endemics in the Pacific coastal zone of Mexico to be of conservation concern. Finally, we also make suggestions on the future direction of revisionary research for the Theraphosidae as a whole.

http://zoobank.org/urn:lsid:zoobank.org:pub:B37F7795-3F92-4334-A0C7-65C8026EE1FB

Update soon !

Morphology still plays a key role in the systematics and phylogenetics of most of the scorpion families and genera, including the Diplocentridae Karsch, 1880. The monophyly of this family, and the monophyly of its two subfamilies is supported by morphological characters; however, neither hypothesis has been tested using molecular data. The lack of a molecular phylogeny has prevented the study of the evolution of morphology within the family. Here, we examine the morphological evolution of several key character systems in diplocentrid systematics. We tested the monophyly of the Diplocentridae, and subsequently the validity of its two subfamilies using a five-locus phylogeny. We examined the variation and evolution of the shape of the carapace, the external surface of the pedipalp patella and the retrolateral surface of the pedipalp chelae of males and females. We also examined the phylogenetic signal of discrete and continuous characters previously reported. We show that Diplocentridae is monophyletic, but Nebinae is nested within Diplocentrinae. Therefore, Nebinae is synonymised with Diplocentrinae (new synonymy). Finally, we show that a new character system proposed here, tarsal spiniform and macrosetal counts, retains high phylogenetic signal and circumscribes independently evolving substructures within this character system.

See here http://www.publish.csiro.au/is/IS16078

Abstract

Recent syntheses of phylogeographical data from terrestrial animals in the Mojave and Sonoran deserts have revealed a complex history of geologic and climatic vicariance events. We studied the phylogeography of Smeringurus vachoni to see how vicariance events may have impacted a large, endemic rock scorpion. Additionally, we used the phylogeographical data to examine the validity of two subspecies of S. vachoni that were described using unconventional morphological characters. Phylogenetic, network and SAMOVA analyses indicate that S. vachoni consists of 11 clades mostly endemic to isolated desert mountain ranges. Molecular clock estimates suggest that clades diversified between the Miocene and early Pleistocene. Species distribution models predict a contraction of suitable habitat during the last glacial maximum. Landscape interpolations and Migrate-n analyses highlight areas of gene flow across the Colorado River. Smeringurus vachoni does not comprise two subspecies. Instead, the species represents at least 11 mitochondrial clades that probably diversified by vicariance associated with Pleistocene climate changes and formation of ancient lakes along the Colorado River corridor. Gene flow appears to have occurred from west to east across the Colorado River during periodic river avulsions  Thanks to Matt for sending PDF.See at
 https://academic.oup.com/biolinnean/article-abstract/doi/10.1093/biolinnean/blx058/3869551/Ancient-lakes-Pleistocene-climates-and-river?redirectedFrom=fulltext

Medical application in scorpion’s venom?A team of Mexican biotechnology researchers has identified a molecule in scorpion venom that could serve both as an aid in antibiotic delivery and as a bactericide disinfectant

Medical application in scorpion’s venom?

Abstract

Diplocentrus duende n. sp. is described based on adult males collected from a locality in the Tehuacán–Cuicatlán Valley, Mexico. This species has punctate pedipalp surfaces, a condition present only in four other species of this specious genus. As suggested here, this condition has evolved independently in these species within the “mexicanus” group of Diplocentrus from the rest of the diplocentrids

See at http://www.sciencedirect.com/science/article/pii/S163106911730063X

Mexican red-kneed tarantulas of the genus Brachypelma are regarded as some of the most desirable invertebrate pets, and although bred in captivity, they continue to be smuggled out of the wild in large numbers. Species are often difficult to identify based solely on morphology, therefore prompt and accurate identification is required for adequate protection. Thus, we explored the applicability of using COI-based DNA barcoding as a complementary identification tool. Brachypelma smithi (F. O. Pickard-Cambridge, 1897) and Brachypelma hamorii Tesmongt, Cleton & Verdez, 1997 are redescribed, and their morphological differences defined. Brachypelma annitha is proposed as a new synonym of B. smithi. The current distribution of red-kneed tarantulas shows that the Balsas River basin may act as a geographical barrier. Morphological and molecular evidence are concordant and together provide robust hypotheses for delimiting Mexican red-kneed tarantula species. DNA barcoding of these tarantulas is further shown to be useful for species-level identification and for potentially preventing black market trade in these spiders. As a Convention on International Trade in Endangered Species (CITES) listing does not protect habitat, or control wildlife management or human interactions with organisms, it is important to support environmental conservation activities to provide an alternative income for local communities and to avoid damage to wildlife populations.

See at : http://www.publish.csiro.au/IS/IS16023

See PDF at http://www.science.marshall.edu/fet/euscorpius/p2017_237.pdf

 

Summary:  Genus Graemeloweus, gen. nov. (Scorpiones: Vaejovidae) is described from northern California, USA. The genus is composed of three species formerly placed in Pseudouroctonus: Graemeloweus iviei (Gertsch et Soleglad, 1972), comb. nov. (type species), G. glimmei (Hjelle, 1972), comb. nov., and G. maidu (Savary et Bryson, 2016), comb. nov. Major diagnostic characters of Graemeloweus include a non-bifurcated primary lamellar hook, the presence of a secondary lamellar hook, a complex mating plug with a two part base and an asymmetric crescent-shape barb, and the presence of a well-developed ventromedian (V2) carina on the pedipalp chela. Evidence is presented suggesting that Graemeloweus is more closely related to Kovarikia than Pseudouroctonus.

Note:  See https://www.researchgate.net/profile/Graeme_Lowe/publications