P. karelini exhibits sexual dimorphism, with females being larger than males. Females may attain a total length of 94 cm (37 in), including a tail 23 centimetres (9.1 in) long. Males may attain a total length of 83.5 cm (32.9 in), with a tail 22.5 cm (8.9 in) long.[4]
Dorsally, it is pale gray or tan, with a series of black crossbars, which are narrower than the spaces between them. Some individuals lack the crossbars, and instead have an orange vertebral stripe. Ventrally, it is whitish, pinkish, or yellowish.[2][4]
^ abBoulenger GA (1893). Catalogue of the Snakes in the British Museum (Natural History). Volume I., Containing the Families ... Colubridæ Aglyphæ, part. London: Trustees of the British Museum (Natural History). (Taylor and Francis, printers). xiii + 448 pp. + Plates I-XXVIII. ("Zamenis karelinii [sic]", pp. 401–402).
^ abSmith MA (1943). The Fauna of British India, Ceylon and Burma, Including the Whole of the Indo-Chinese Sub-region. Reptilia and Amphibia. Vol. III.—Serpentes. London: Secretary of State for India. (Taylor and Francis, printers). xii + 583 pp. (Coluber karelini, pp. 169–170).
^Beolens, Bo; Watkins, Michael; Grayson, Michael (2011). The Eponym Dictionary of Reptiles. Baltimore: Johns Hopkins University Press. xiii + 296 pp. ISBN978-1-4214-0135-5. (Coluber karelini mintonorum, p. 179).
Further reading
Brandt [JF] (1838). "Note sur quatre nouvelles espèces de serpents de la côte occidentale de la mer Caspienne et de la Perse septentrionale, découvertes par M. Kareline ". Bulletin Scientifique de l'Académie Impériale des Sciences de Saint-Pétersbourg3 (16): 241-244. (Coluber karelini, new species, p. 243). (in French and Latin).
Latifi M (1991). The Snakes of Iran. Oxford, Ohio: Society for the Study of Amphibians and Reptiles. 156 pp. ISBN0-916984-22-2. (Coluber karelini, p. 104).
Nagy ZT, Lawson R, Joger U, Wink M (2004). "Molecular phylogeny and systematics of racers, whip snakes and relatives (Reptilia: Colubridae) using mitochondrial and nuclear markers". Journal of Zoological Systematics and Evolutionary Research42: 223-233. (Platceps karelini, new combination).
Szczerbak, Nikolai (2003). Guide to the Reptiles of the Eastern Palearctic. Malabar, Florida: Krieger Publishing. 350 pp. ISBN978-1-57524-004-6.