REVUE SUISSE DE ZOOLOGIE, vol.108, no.1, pp.11-30, 2001 (SCI-Expanded, Scopus)
Zamenis dahlii collaris Muller, 1878 is the oldest available name for the red headed or Muller's whip snake. Following the principle of priority, it replaces Z. d. rubriceps Venzmer, 1919. A lectotype is designated for Coluber (sensu late) collaris (Muller). This monotypic eastern Mediterranean species has been recorded from the littoral of the Black Sea in Bulgaria south of Burgas, the coastal areas of Turkey, and the Levant as far as southern Jordan. The number and arrangement of certain head scales, and in particular the preoculars and temporals, are variable. Usually, there are 19 longitudinal rows of dorsal scales at midbody followed by lateral and paravertebral reduction levels; specimens from southwestern Anatolia mostly have 17 rows on the anterior half and at midbody, and paravertebral reductions. Ventral and subcaudal values follow a west-east dine; the highest counts occur in Near East populations. C. collaris differs from its sister species, C. (s. l.) najadum (Eichwald, 1831), in body scale counts and details of the colour pattern.