Lithobates catesbeianus

Leyte-Manrique, Adrian, Mata-Silva, Vicente, Báez-Montes, Óscar, Fucsko, Lydia Allison, DeSantis, Dominic L., García-Padilla, Elí, Rocha, Arturo, Johnson, Jerry D., Porras, Louis W. & Wilson, Larry David, 2022, The herpetofauna of Guanajuato, Mexico: composition, distribution, and conservation status, Amphibian & Reptile Conservation (e 321) 16 (2), pp. 133-180 : 144-152

Lithobates catesbeianus ** Gerrhonotus liocephalus

Hemidactylus frenatus **

Hemidactylus turcicus **

Plestiodon dugesii *

Geophis dugesii *

Geophis petersii *

Adelophis copei *

Five of the 10 single-region TVB species are country endemics (50.0%), two are non-endemics (20.0%), and the three indicated by double-asterisks are non-natives (30.0%).

In summary, of the 32 single-region species, 15 are non-endemics (46.9%), 14 are country endemics (43.8%), and three are non-natives (9.4%). Of the three physiographic regions, the SMO has considerable conservation significance (but see section on Relative Herpetofaunal Priority), inasmuch as it contains the highest numbers of species (75 of 101, or 74.3%), country endemics (37 of 56, or 66.1%), and single-region species (22 of 32, or 68.8%). No. 9. Lithobates neovolcanicus (Hillis and Frost, 1985) . The distribution of the Transverse Volcanic Leopard Frog is in pine-oak forest and mesquite-grassland at elevations from 1,500 to 2,500 m along the southern edge of the Mexican Plateau in the states of Guanajuato, Jalisco, Colima, Zacatecas, Michoacán, México, and Hidalgo, Mexico ( Frost 2022). This individual came from San Nicolás de los Agustinos, in the municipality of Salvatierra. Wilson et al. (2013b) calculated its EVS as 13, placing it at the upper limit of the medium vulnerability category. IUCN has judged its conservation status as Near Threatened, but SEMARNAT has not listed this species. Photo by Adrian Leyte-Manrique.

No. 11. Ambystoma velasci (Dugés, 1888) . The Plateau Tiger Salamander is a Mexican endemic occurring from “northwestern Chihuahua south along the eastern slope of the Sierra Madre Occidental and southern Nuevo Leon to Hidalgo in the Sierra Madre Oriental, west to Zacatecas, and south into the Transverse Volcanic range of central Mexico ” ( Frost 2022). This individual was photographed in pine-oak forest within the Reserva de la Biósfera Sierra Gorda in the community of El Ocotero, in the municipality of Xichú. Wilson et al. (2013b) calculated its EVS as 10, placing it at the lower limit of the medium vulnerability category. IUCN has considered its conservation status as Least Concern, and SEMARNAT as a species of Special Protection (Pr). Photo by Adrian Leyte-Manrique.

No. 10. Spea multiplicata (Cope, 1863) . The distribution of the Mexican Spade-foot Toad is in southeastern Utah and southern Colorado through western Oklahoma, Arizona, New Mexico, and West Texas, in the USA, southward to the southern edge of the Mexican Plateau as far as Nayarit, Guerrero, Oaxaca, Hidalgo, and Tlaxcala, Mexico, at elevations from sea level to 2,743 m ( Frost 2022). This individual came from La Torrecilla within Área Natural Protegida Las Musas, in the municipality of Manuel Doblado. Wilson et al. (2013b) reported its EVS as 6, placing it in the middle of the low vulnerability category. IUCN has not evaluated its conservation status, and SEMARNAT has not listed this species. Photo by Adrian Leyte-Manrique.

No. 12. Isthmura bellii (Gray, 1850) . Bell’s Salamander is a Mexican endemic occurring from “southern Tamaulipas, Tlaxcala, Hidalgo and the Sierra Madre del Sur of Guerrero, Mexico, and west and north to southern Nayarit and southern Zacatecas ” ( Frost 2022). This individual was found in the Sierra de los Agustinos, in the municipality of Guanajuato. Wilson et al. (2013b) established its EVS as 12, placing it in the upper portion of the medium vulnerability category. IUCN has judged its conservation status as Vulnerable, and SEMARNAT lists this species as Threatened (A). Photo by José Carlos Arenas-Monroy.

A Coefficient of Biogeographic Resemblance (CBR) matrix was constructed using the Duellman (1990) algorithm to assess the herpetofaunal similarity relationships among the three physiographic regions in Guanajuato ( Table 6). These data were then used to produce a UPGMA dendrogram ( Fig. 10 ; Sokal and Michener 1958). The SMO harbors the greatest amount of species richness (75 species), and the CP has the least (60 species). The average species richness value for the three regions is 69.7. The lowest number of shared species (44) is between the CP and the SMO, which is interesting inasmuch as these two regions of the state abut one another. The highest number of shared species (56) is between the CP and the TVB, two regions that also contact one another.

Distribution Status Categorizations

The system employed by Alvarado-Díaz et al. (2013) and the remainder of the MCS entries (see above) was used to analyze the distributional status of members of the Guanajuato herpetofauna. The three categories that apply to the Guanajuato herpetofauna are non-endemic, country endemic, and non-native. No state endemic species are known to occur in Guanajuato. The basic data are given in Table 7 and summarized in Table 8.

The numbers of species in each of these three categories, in descending order of size, are as follows: country endemics, 56 (55.4%); non-endemics, 40 (39.6%); and non-natives, five (5.0%). In this fashion, the Guanajuato herpetofauna resembles those of many of the other states dealt with in the MCS, i.e., the largest number of species occupies the country endemic category, as was found in Michoacán ( Alvarado-Díaz et al. 2013), Nayarit ( Woolrich-Piña et al. 2016), Jalisco (Cruz Sáenz et al. 2017), Puebla ( Woolrich-Piña et al. 2017), Hidalgo ( Ramírez-Bautista et al. 2020), and Querétaro ( Cruz-Elizalde et al. 2022). In other states, the number of non-endemic species exceeds that of the country endemic species: Oaxaca ( Mata-Silva et al. 2015); Chiapas ( Johnson et al. 2015a); Tamaulipas ( Terán-Juárez et al. 2016); Nuevo León (Nevárez-de los Reyes et al. 2016); the Mexican Yucatan Peninsula ( González-Sánchez et al. 2017), Coahuila ( Lazcano et al. 2019), Veracruz ( Torres-Hernández et al. 2021), and Tabasco ( Barragán-Vázquez et al. 2022).

As noted above, in some instances in the MCS the number of country endemics is higher than the number of non-endemic species, whereas in other cases the reverse is true. Therefore, the ratios of country endemics to non-endemic species vary extensively. The ratios in which the number of country endemics is higher than the number of non-endemics range from 0.53 in the case of Jalisco to 0.88 in Hidalgo. The ratios in which the number of non-endemics exceeds the number of country endemics range from 1.12 in the case of Oaxaca ( Mata-Silva et al. 2015) to 127.0 in the Yucatan Peninsula ( González-Sánchez et al. 2017). In general, the nature of this ratio depends on how close the state in question is to either the United States or Central America. This ratio also depends upon the size of these two aspects of a given herpetofauna as to whether the ratio will be more or less than one. So, we would expect that the herpetofaunas of states more or less equidistant from both the USA and Central America ( Guatemala and/or Belize) would have ratios closer to one. As noted in Torres-Hernández et al. (2021): “In the case of the three MCS states that border the USA, the ratios are 3.22 (100/ 31 in Coahuila; Lazcano et al. 2019), 2.44 (95/ 39 in Nuevo León; Navárez-de los Reyes et al. 2016), and 2.32 (130/ 56 in Tamaulipas; Terán-Juárez et al. 2016). In the case of the states or the region sharing a border with Central America, the ratios are 8.38 (268/ 32 in Chiapas; Johnson et al. 2015a) and 127.0 (127/ 1 in the Yucatan Peninsula; González-Sánchez et al. 2017). The extremely high ratio for the Yucatan Peninsula is due, at least in part, to this region lying adjacent to its southern portion lying in northern Guatemala.”

The five non-native species reported as occurring in Guanajuato are Lithobates catesbeianus , Hemidactylus frenatus , H. turcicus , Virgotyphlops braminus , and Trachemys scripta . Two of these species ( H. frenatus and V. braminus ) are the most widespread of the non-native species recorded in the previous 14 MCS entries, inasmuch as they have been reported in 14 and 15 states, respectively.

No. 13. Barisia imbricata (Wiegmann, 1828) . The Imbricate Alligator Lizard is a Mexican endemic inhabiting the mountains of the Transmexican Volcanic Belt and the Sierra Madre Occidental in the states of México, Distrito Federal, Querétaro, Hidalgo, Jalisco, Puebla, Michoacán, Morelos, and Tlaxcala; additional isolated populations have been recorded in Oaxaca and Veracruz ( Ramírez-Bautista et al. 2014). This individual was found in Sierra del Tigre, in the municipality of Mazamitla. Wilson et al. (2013a) determined its EVS as 14, placing it at the lower limit of the high vulnerability category. IUCN has judged its conservation status as Least Concern, and SEMARNAT as a species of Special Protection (Pr). Photo by Adrian Leyte-Manrique.

No. 15. Sceloporus spinosus (Wiegmann, 1828) . The Eastern Spiny Lizard is a widespread endemic species found over much of central Mexico, at elevations from 1,500 to 2,300 m asl (Florez and Gerez 1994). This individual was photographed in Temascatio, in the municipality of Irapuato. Wilson et al. (2013a) ascertained its EVS as 12, placing it in the upper portion of the medium vulnerability category. IUCN has assessed its conservation status as Least Concern, but SEMARNAT has not listed this species. Photo by Adrian Leyte -Manrique.

No. 14. Norops nebulosus (Wiegmann, 1834) . The Clouded Anole is a Mexican endemic distributed from “ Sinaloa to the Isthmus of Tehuantepec on the Pacific coast, extending to the states of Morelos, Puebla, and Durango ” (translation ours; Santiago-Pérez et al. 2012: 136). This individual was encountered at Cuchicuato, in the municipality of Irapuato. Wilson et al. (2013a) determined its EVS as 13, placing it at the upper limit of the medium vulnerability category. IUCN has assessed its conservation status as Least Concern, but SEMARNAT has not listed this species. Photo by Adrian Leyte-Manrique.

No. 16. Plestiodon lynxe (Wiegmann, 1834) . The Oak Forest Skink is a Mexican endemic distributed in southern San Luis Potosí, Guanajuato, Querétaro, Hidalgo, and the mountains of western Veracruz, with isolated populations occurring in southern Durango, southwestern Zacatecas, southeastern Nayarit, and Jalisco ( Webb 1968; Ponce-Campos and Romero-Contreras 2006; Canseco-Márquez et al. 2007; Lemos-Espinal and Dixon 2013). This individual was encountered at Puente de Camotlán, in the municipality of La Yesca. Wilson et al. (2013a) determined its EVS as 10, placing it at the lower limit of the medium vulnerability category. IUCN has judged its conservation status as Least Concern, and SEMARNAT as a species of Special Protection (Pr). Photo by Adrian Leyte-Manrique.

Wilson et al. (2017) originated a system for categorizing the distribution of the non-endemic species in the Mexican herpetofauna. The categorizations of the 40 non-endemic species in Guanajuato ( Table 9) indicate that the largest number of these 40 species (26, or 65.0%) are MXUS species, i.e., those that occur in both Mexico and the United States. The next highest number (six, or 15.0%) are USCA species, i.e., species that range from the United States through Mexico to some point in Central America. The remaining eight species are MXCA species (four, or 10.0%), MXSA species (three, or 7.5%), or USSA species (one, or 2.5%).

Figures

Fig. 10. UPGMA generated dendrogram illustrating the similarity relationships of species richness among the herpetofaunal components in the three physiographic regions of Guanajuato (based on the data in Table 6; Sokal and Michener 1958). Similarity values were calculated using the Coefficient of Biogeo- graphic Resemblance (CBR) of Duellman (1990).