Lampropeltis zonata complex

In 1952 Richard Zweifel, based upon his examination of 238 specimens, recognized seven subspecies of Lampropeltis zonata, including two taxa he newly described (parvirubra and pulchra). His findings were limited to pattern and color variations observed within his sample, specifically the number of body triads, percentage of confluent triads, the position of the first white ring, and the presence or absence of red on the snout (Zweifel, 1952). Zweifel affirmed his results 22 years later in a species account for the Catalogue of American Amphibians and Reptiles, citing newer literature without fundamentally altering his diagnoses for the seven geographic races (Zweifel, 1974).

In 1999 Rodriguez-Robles et al. examined an additional 321 specimens of L. zonata and found that Zweifel’s diagnostic characters overlapped to such an extent as to render them of little value in determining the identity of the seven subspecies recognized in the 1952 study. Additionally, Rodriguez-Robles et al. performed a mitochondrial DNA sequencing analysis based on 34 tissue samples that produced 32 haplotypes (also showing considerable overlap among the recognized subspecies) within two major clades (Northern and Southern) and two subclades within the Northern clade (Rodriguez-Robles et al., 1999). We at SWCHR generally consider mtDNA analyses inappropriate tools (in and of themselves) for determining the validity of subspecies, but when taken in tandem with their evaluation of pattern and coloration in this species, this molecular data appears to support the contention that seven subspecies of L. zonata are not supported.

Brian Hubbs (2004), in his thorough review of the natural history of this species, provided accounts for all seven subspecies while acknowledging the possibility that several of them were perhaps invalid. Most L. zonata fanciers who continue to assert an ability to distinguish between the Zweifel subspecies cannot provide testable diagnoses other than the “gestalt” of the animals, leading us to suspect that what they are actually seeing are localized geographical morphs rather than valid, definable subspecies.

Consequently, we at SWCHR, while suspecting that several valid subspecies are included within the L. zonata complex, agree with the determination of the Rodriguez-Robles et al. paper that it would not be prudent to recognize taxa that cannot currently be meaningfully defined. In fact, we can do no better than to quote one of the conclusions of those authors while commending them for their remarkable taxonomic restraint, given the current tendency of phylogenetics: ” . . . (W)e hesitate to propose nomenclatural changes using mtDNA patterns as the sole criterion for determining species boundaries, and thus await the completion of morphological and other studies before determining which taxonomic arrangement better reflects evolutionary relationships within the L. zonata complex.” (Rodriguez-Robles et al., op. cit.).


Literature Cited

Hubbs, B. 2004. Mountain Kings: A Collective Natural History of California, Sonoran, Durango and Queretaro Mountain Kingsnakes. Tempe, AZ: Tricolor Books

Rodríguez-Robles, J. A., D. F. DeNardo, and R. E. Staub. 1999. Phylogeography of the California Mountain Kingsnake, Lampropeltis zonata (Colubridae). Molecular Ecology. 8(11): pp. 1923-1934.

Zweifel, R. 1952. Pattern variation and evolution of the Mountain Kingsnake, Lampropeltis zonata. Copeia (1952) 3:152-168.

Zweifel, R. 1974. Lampropeltis zonata. Catalogue of American Amphibians and Reptiles, 174.1-174.4. Society for the Study of Amphibians and Reptiles, Athens, OH.


19 Apr 2010

SWCHR Committee on Common and Scientific Names
Tom Lott, Committee Chair
Terry Cox
Riley J. Campbell
Gerald Keown (ex officio member)

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