Lampropeltis holbrooki ( Stejneger 1903 )

Pyron, Alexander & Burbrink, Frank T., 2009, Systematics of the Common Kingsnake (Lampropeltis getula; Serpentes: Colubridae) and the burden of heritage in taxonomy, Zootaxa 2241, pp. 22-32 : 26

Lampropeltis holbrooki ( Stejneger 1903)

( Figs. 1–3 )

Speckled Kingsnake

Holotype: Unknown

Type Locality: ‘Valley of the Mississippi’ (Holbrook 1842), restricted to Hot Springs, Arkansas ( Schmidt 1953).

Etymology: Specific epithet is a patronym honoring John Edwards Holbrook, a prominent American herpetologist of the 19th century, known as the ‘father of North American Herpetology’.

Synonymy: This species is essentially co-terminous with populations of the previously recognized subspecies L. g. holbrooki occurring west of the Mississippi River.

Diagnosis: The Speckled Kingsnake ( L. holbrooki ) is a medium- to large-bodied constrictor with a maximum adult size of 183cm and a mean adult range of 90–122cm ( Conant & Collins 1998). Scales are smooth, anal plate single, and midbody scale rows number 19–25 ( Blaney 1977). Ventral scales number 197– 222 in both sexes, with subcaudals ranging from 46–59 in males and 37–51 in females ( Blanchard 1921; Blaney 1977). The Speckled Kingsnake occurs west of the Mississippi River, from Iowa and Nebraska in the north to the Gulf Coast, and west to west-central Texas ( Fig. 2 ). The majority of the range of L. holbrooki is characterized by the ‘speckled’ pattern, which consists of a black ground color, with a white or yellow speckle in the center of each scale, and very occasionally a faint trace of dorsal crossbanding ( Fig. 3 ). Large geographical areas harboring at least superficial morphological intermediacy between the Speckled Kingsnake and the Desert lineage in west central Texas are apparently inhabited only by the Speckled Kingsnake, suggesting that such color pattern variation may be due to phenotypic responses to ecological gradation, rather than hybridization or introgression ( Pyron & Burbrink 2009 c). The precise western extent of the range of L. holbrooki is unclear, but ecological niche modeling predicts that the range extends approximately to the Pecos and Rio Grande River drainages (see Fig. 4 in Pyron & Burbrink 2009 c; Fig. 2 ).

Figures

FIGURE 1. Chronogram showing genetic structure, geographic location, and divergence times of the five species in the Lampropeltis getula complex, from Pyron & Burbrink (2009 c). The dates and depth of the terminal triangles represent the time of the most recent common ancestor of that lineage, while the height of the triangles is proportional to the number of samples in the clade. Dates at nodes represent the mean and 95 % credible interval for that node, while numbers above branches represent Bayesian posterior probability support. Divergence times and support values are from Pyron & Burbrink (2009 c).

FIGURE 2. Range map of the five lineages recovered by Pyron & Burbrink (2009 c), corresponding to five distinct species in North America. Note the zones of sympatry between L. californiae and L. splendida, and L. nigra and L. getula.

FIGURE 3. Primary color pattern variants of five species of the Lampropeltis getula group. Many additional variants occur regionally; these are simply the primary color pattern classes of the five species. See Blaney (1977), Conant & Collins (1998), Stebbins (2003), and Krysko & Judd (2006) for more detailed descriptions of color pattern variation. Photograps of L. getula (R), L. nigra (R), L. holbrooki (L), and L. californiae are compliments S. L. & J. T. Collins, CNAH. The photograph of L. holbrooki (R) is compliments D. B. Shepard, CUNY-CSI.