Genus Naja (Elapidae, Serpentes) (True cobras): Current systematics, toxinological characteristics, and ecological groups

   This review of world literature presents the topical taxonomy, zoogeography and toxinology of the most dangerous and poisonous snakes of the genus Naja (True cobras), including questions of origin, distribution and mechanism of toxic effect in the ecological group of “spitting cobras”. Cobras are among the most famous snakes in the world, but cobra taxonomy remained surprisingly poorly understood until the late 20th century. The application of molecular-phylogenetic research methods has led to the “Afro–Asian race for diversity”, i.e. an increase in the number of recognized African and Asian cobra species, which required the truly “revolutionary” introduction of the subgenera rank for herpetology, while maintaining the nomenclatural stability of the group of iconic species. The cobra taxonomy issues have not only an important theoretical aspect, but also purely applied (medical and zootoxinological) ones. Incomplete (or questionable) under-standing of the taxonomic position of some species may lead to dramatic errors in the treatment of snakebite poisonings, and most often – to the incorrect use of monovalent antisnake serums, since often closely and similar snake species may have poisons differing in composition, and therefore in the mechanism of action. Cobras belong to the group of primarily poisonous armed actively poisonous animals, with plastic adaptation to the environment. The current state of re-search of the unique set of polypeptide toxins in cobra venom, which serve as chemical factors (allomones) of interspecies (allelochemical) interactions, is of great theoretical and practical significance. Similar examples could be found among animals of many systematic groups, but cobras have a surprisingly balanced variety of hunting and defense methods using their poisonous apparatus – parenteral poison administration during a bite and “spitting” during remote contact.

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