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

  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 Kiekie Polotow & Brescovit, 2018 (Araneae: Ctenidae) from the highlands of Panama

 



Two new species of Kiekie Polotow & Brescovit, 2018 (Araneae: Ctenidae) from the highlands of Panama


Abstract

Two new species, Kiekie almae sp. n. and K. dietrichi sp. n. are described based on both sexes collected in highlands of Central America (Panama). Live males and females of both species were photographed in situ. A distribution map of all Panamanian Kiekie species is given based on new and literature-derived records.