Two new arthropod toxins purified from the venom of the Mexican scorpion Centruroides nigrescens

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  Two new arthropod toxins purified from the venom of the Mexican scorpion Centruroides nigrescens Abstract The venom of the slender black scorpion Centruroides nigrescens , from the State of Guerrero México, was fractionated by Sephadex G–50 gel filtration, followed by carboxymethyl cellulose ion separation and high–performance liquid chromatography, permitting to obtain two new peptides toxic to arthropods. The estimate LD 50 of the soluble venom for the insect Acheta domesticus was 11.1 μg/g body weight, and for the arthropod Armadillidium vulgare was 61.1 μg body weight . The amino acid sequence of toxin Cnige1 (toxic to A. domesticus and A. vulgare ) contains 65 amino acids, with a molecular mass of 7273.37 mass units, whereas toxin Cnige2, toxic to A. domesticus , contains 68 amino acids, with a molecular mass of 7548.81 units. Both peptides are well packed, containing 8 cysteines, which in the native venoms are forming 4 disulfide bridges each. The amino acid sequences f...

Two new species of the remarkable scorpion genus Megacormus Karsch, 1881 (Scorpiones: Euscorpiidae)

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Two new species of the remarkable scorpion genus Megacormus Karsch, 1881 (Scorpiones: Euscorpiidae)


Abstract

Two new species of the very interesting euscorpiid scorpion genus Megacormus Karsch, 1881, are herein described from eastern Mexico. Both had been previously misidentified in the published literature, one as Megacormus segmentatus Pocock, 1900, the other as Megacormus granosus (Gervais, 1844), but the direct comparison of adults of both sexes to adult topotypes from all members of the genus currently accepted as valid taxa, revealed solid morphological characters that warrant their recognition as distinct taxa. Both new species seem also to be endemics with a small distribution area, but apparently not restricted to a single locality. This addition raises the known composition of the genus to eight species, all of them exclusively from mountain sites of eastern Mexico.


Teruel, R., Kovařík, F., Lowe, G., & Šťáhlavský, F. 2023 . Two new species of the remarkable scorpion genus Megacormus Karsch, 1881 (Scorpiones: Euscorpiidae). Euscorpius, No. 375: 1-22.