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Ojanguren-Affilastro A.A.,Museo Argentino de Ciencias Naturales Bernardino Rivadavia | Mattoni C.I.,National University of Cordoba | Ochoa J.A.,Frankfurt Zoological Society Peru | Ramirez M.J.,Museo Argentino de Ciencias Naturales Bernardino Rivadavia | And 2 more authors.
Molecular Phylogenetics and Evolution | Year: 2016

A phylogenetic analysis of the scorpion genus Brachistosternus Pocock, 1893 (Bothriuridae Simon, 1880) is presented, based on a dataset including 41 of the 43 described species and five outgroups, 116 morphological characters and more than 4150 base-pairs of DNA sequence from the nuclear 18S rDNA and 28S rDNA gene loci, and the mitochondrial 12S rDNA, 16S rDNA, and Cytochrome c Oxidase Subunit I gene loci. Analyses conducted using parsimony, Maximum Likelihood and Bayesian Inference were largely congruent with high support for most clades. The results confirmed the monophyly of Brachistosternus, the nominal subgenus, and subgenus Ministernus Francke, 1985, as in previous analyses based only on morphology, but differed in several other respects. Species from the plains of the Atacama Desert diverged basally whereas the high altitude Andean species radiated from a more derived ancestor, presumably as a consequence of Andean uplift and associated changes in climate. Species limits were assessed among species that contain intraspecific variation (e.g., different morphs), are difficult to separate morphologically, and/or exhibit widespread or disjunct distributions. The extent of convergence in morphological adaptation to life on sandy substrata (psammophily) and the complexity of the male genitalia, or hemispermatophores, was investigated. Psammophily evolved on at least four independent occasions. The lobe regions of the hemispermatophore increased in complexity on three independent occasions, and decreased in complexity on another three independent occasions. © 2015 Elsevier Inc.

Escobar E.,National Major San Marcos University | Tincopa R.,National Major San Marcos University | Ochoa J.A.,Frankfurt Zoological Society Peru
Revista Peruana de Biologia | Year: 2013

The biochemistry of the venom of Tityus kaderkai Kovarik, 2005 from Madre de Dios depart?ment, has been studied. The soluble venom contains 47.6% of protein. The venom proteins were separated from 12.9 mg of venom using cationic exchange chromatography in CM Sephadex C-25 with a 0.05 M ammonium acetate buffer pH 7.0. The chromatography profiles show seven peaks of proteins (I - VII) and five protein bands were distinguished in the crude venom, by PAGE-SDS. The toxicity assays allowed the identification of three toxins affecting Mus musculus which were associated to peaks IV, V and VII. Toxic proteins to Gryllus sp. were also found associated to peaks IV, V, VI and VII. Through the enzymatic activity, the presence of proteolytic activity over casein was found related to the first peak. Hyaluronidase activity has also been found in the peak IV with a specific activity 205.6 μg/min/mg. However, the crude venom and collected fractions did not show any phospholipase, anticoagulant, nor hemolytic activity. Notes on the distribution pattern and habitat are also included. © Los autores.

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