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Permanent 1 m^2 vegetation plots were established near each of the 88 Saddle grid stakes in 1989 by Marilyn Walker, who led the sampling effort until 1997. To estimate plant canopy cover, point quadrat measurements have been made at irregular intervals from 1989 to the present (1989, 1990, 1995, 1997, 2006, 2008 and yearly from 2010 onward). The point-quadrat technique used for sampling was described in Spasojevic et al. (2013) and Auerbach (1992). Auerbach, N. 1992. Effects of road and dust disturbance in minerotrophic and acidic tundra ecosystems, northern Alaska. University of Colorado, Boulder, Colorado, USA. Spasojevic, Marko J, William D Bowman, Hope C Humphries, Timothy R Seastedt, and Katharine N Suding. Changes in alpine vegetation over 21 years: Are patterns across a heterogeneous landscape consistent with predictions?” Ecosphere 4, no. 9 (2013): 1–18. https://doi.org/10.1890/es13-00133.1.
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Diploid Parthenogenetic Common Checkered Whiptail (Aspidoscelis tesselatus): Observations on the Species in Cimarron County in Extreme Western Oklahoma
Copyright © Notice: Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) SONORAN HERPETOLOGIST 37 (3) 2024 139 Introduction The Common Checkered Whiptail (Aspidoscelis tesselatus; Say, 1823) has the most extensive natural geographic distribution among the eight diploid parthenogenetic species recognized in that genus [i.e., A. cozumela (Gadow, 1906), A. maslini (Fritts, 1969), and A. rodecki (McCoy and Maslin, 1962) in the A. cozumela species group; A. laredoensis (McKinney et al., 1973) and A. preopatae (Barley et al., 2021) in the A. sexlineatus group; A. dixoni (Scudday, 1973), A. neomexicanus (Lowe and Zweifel, 1952), and A. tesselatus (Say in James, 1823) in the A. tesselatus group]. The adaptability of A. tesselatus will become even more apparent in a forthcoming report by other scientists on its introduction to and establishment in habitats in California a great distance west of its natural geographic distribution area. Although Zweifel (1965) categorized the extensive color pattern variation in Cnemidophorus = Aspidoscelis tesselatus by recognition of informal pattern classes A, B, C, D, E, and F, subsequent studies have recognized A and B as belonging to the triploid parthenogenetic species Cnemidophorus = Aspidoscelis neotesselatus (Walker, Cordes, and Taylor, 1997) described by Walker et al. (1997) from southeastern Colorado and F as belonging to the diploid parthenogenetic species Cnemidophorus = Aspidoscelis dixoni (Scudday, 1973) described by Scudday (1973) from Hidalgo County, New Mexico, and arrays in Presidio County, Texas. These taxonomic reallocations of some of the pattern classes recognized by Zweifel (1965) to different species reduced the known distribution area of what we currently recognize as A. tesselatus by relatively small areas in Colorado, New Mexico, and Texas, USA. Walker et al. (1994), Walker et al. (1997), Cordes and Walker (2006), and Cole et al. (2007) recognized the arrays (we reserve the term population for species with males and females) of lizards in a small area of Hidalgo County, New Mexico, USA, as pattern class C of A. dixoni, and restricted pattern classes A and B of that species to relatively small areas in Presidio County, Texas. Two of us (JEC and JMW) have found one or more arrays of pattern classes C, D, and E of diploid A. tesselatus to be easily located, abundant, and readily observable at close range in a variety of habitats in parts of Colorado, New Mexico, and Texas, and Chihuahua state, México, as also indicated by Zweifel (1965), Taylor et al. (1996, 2005), Walker et al. (1997), and Taylor (2021). The only exception to the preceding statement pertains to the small geographic area of occurrence of A. tesselatus in Oklahoma, specifically in Cimarron County, which is the westernmost extension of the panhandle of the state. In fact, all the whiptail lizard specialists coauthoring this report (i.e., MAP, JEC, and JMW) have felt the sting of disappointment during repeated attempts to locate and study this species in the state! The total number of A. tesselatus pattern class C lizards observed during the many individual visits to Cimarron County by members of that group was one adult by JEC on 31 July 2015. The purpose of this report is to review what little is known about A. tesselatus in the state of Oklahoma and to document its current presence in the state through a series of recent observations made of this species in Cimarron County, Oklahoma.
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- Award ID(s):
- 1911370
- PAR ID:
- 10637622
- Publisher / Repository:
- ResearchGate
- Date Published:
- Journal Name:
- ResearchGate.net
- ISSN:
- 384113725
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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