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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. 

Porous non-woven fibrous media are widely used in various industrial applications such as filtration, insulation, and medical textiles due to their unique structural and functional properties. However, predicting the mechanical behavior of these materials is challenging due to their complex microstructure and anisotropic nature. In this study, a computational model is developed to simulate the mechanical response of porous non-woven fibrous media under external loading. The model is based on the finite element method and takes into account the geometric and material properties of the fibers and the void spaces between them. The effects of various factors such as fiber size, porosity, and fibers’ intersection ratio on the mechanical behavior of the material are investigated. The results reveal that the material’s porosity and fibers’ intersection ratio are the most significant factors influencing its mechanical properties. Additionally, the increase in fiber diameter has a relatively minor effect on the material’s elastic properties. However, such changes in elastic properties are primarily attributed to the increase in randomness within the fibrous network, which is directly related to the fiber diameter for the investigated structure. The proposed computational model predicts the mechanical properties of porous non-woven fibrous media and can provide invaluable insights into the design and optimization of porous non-woven fibrous media for various scientific and engineering applications. 

A natural history note describing unusual coloration of a very old female Aspidoscelis gularis that we observed while doing fieldwork in South Texas. 

This is a natural history note that we published based on an observation of a caudal bifurcation in Aspidoscelis gularis that we witnessed during fieldwork in South Texas. 

With 2.3 billion people around the world lacking adequate sanitation services, attention has turned to alternative service provision models. This study suggests an approach for meeting the sanitation challenge, especially as expressed in Sustainable Development Goal 6.2, using a toilet technology system, such as Pee Power® that generates electricity using diverted urine as a fuel. A field trial was carried out in a girls’ school in Kisoro, Uganda, where the generated electricity was used to light the existing toilet block. The trial was evaluated in terms of social acceptability and user experience using a multidimensional assessment protocol. The results of our assessment show that users felt safer when visiting the toilets at night. Lights provided from the technology also helped with the perceived cleanliness of the toilets. The technology was well accepted, with 97% of the respondents saying that they liked the idea of the Pee Power® technology and 94% preferring it over other facilities on site. This shows how the technology helps meet SDG target 6.2, with its particular focus on vulnerable populations. 

Abstract Unisexual vertebrates typically form through hybridization events between sexual species in which reproductive mode transitions occur in the hybrid offspring. This evolutionary history is thought to have important consequences for the ecology of unisexual lineages and their interactions with congeners in natural communities. However, these consequences have proven challenging to study owing to uncertainty about patterns of population genetic diversity in unisexual lineages. Of particular interest is resolving the contribution of historical hybridization events versus post formational mutation to patterns of genetic diversity in nature. Here we use restriction site associated DNA genotyping to evaluate genetic diversity and demographic history inAspidoscelis laredoensis, a diploid unisexual lizard species from the vicinity of the Rio Grande River in southern Texas and northern Mexico. The sexual progenitor species from which one or more lineages are derived also occur in the Rio Grande Valley region, although patterns of distribution across individual sites are quite variable. Results from population genetic and phylogenetic analyses resolved the major axes of genetic variation in this species and highlight how these match predictions based on historical patterns of hybridization. We also found discordance between results of demographic modelling using different statistical approaches with the genomic data. We discuss these insights within the context of the ecological and evolutionary mechanisms that generate and maintain lineage diversity in unisexual species. As one of the most dynamic, intriguing, and geographically well investigated groups of whiptail lizards, these species hold substantial promise for future studies on the constraints of diversification in unisexual vertebrates.