Research Article |
Corresponding author: Francisco Martín Huerta Martínez ( martin.huerta@academicos.udg.mx ) Academic editor: Uri García-Vázquez
© 2024 Verónica Carolina Rosas-Espinoza, Eliza Álvarez-Grzybowska, Arquímedes Alfredo Godoy González, Ana Luisa Santiago-Pérez, Karen Elizabeth Peña-Joya, Fabián Alejandro Rodríguez-Zaragoza, Leopoldo Díaz Pérez, Francisco Martín Huerta Martínez.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Rosas-Espinoza VC, Álvarez-Grzybowska E, Godoy González AA, Santiago-Pérez AL, Peña-Joya KE, Rodríguez-Zaragoza FA, Díaz Pérez L, Huerta Martínez FM (2024) Taxonomic diversity of amphibians (Amphibia, Anura) and reptiles (Reptilia, Testudines, Squamata) in a heterogeneous landscape in west-central Mexico: a checklist and notes on geographical distributions. ZooKeys 1211: 29-55. https://doi.org/10.3897/zookeys.1211.122565
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In Mexico, land use changes have significantly impacted the diversity of amphibians and reptiles in a negative way. In light of this, we evaluate the alpha and beta components of the taxonomic diversity of amphibians and reptiles in a heterogeneous landscape in west-central Mexico. Additionally, we provide a checklist of amphibian and reptile species recorded over nine years of observations within the studied landscape and surrounding areas. The land cover/use types with the highest species richness and alpha taxonomic diversity differed between amphibians and reptiles. Overall beta taxonomic diversity was high for both groups, but slightly higher in reptiles. This taxonomic differentiation mainly corresponded to a difference in the turnover component and was greater in pristine habitats compared to disturbed ones. The checklist records 20 species of amphibians (ten of which are endemic) and 48 of reptiles (30 endemics). Additionally, the study expands the known geographical distribution range of one species of frog and three species of snakes. Our findings suggest that heterogeneous landscapes with diverse land cover/use types can provide essential habitats for the conservation of amphibian and reptile species.
Crops, herpetofauna, Jalisco state, native vegetation, range extension
Amphibians and reptiles are abundant and diverse components of terrestrial and freshwater ecosystems, serving various ecological functions (
Human pressure on natural environments has been intensifying mainly with agricultural landscapes becoming increasingly dominant. Land-use changes threaten biodiversity, primarily through habitat loss and degradation (
One approach used to quantify the taxonomic complexity of species assemblages at the local level and to evaluate the response of organisms to spatial gradients and differentiation at the regional level has been to analyze the alpha (local) and beta (turnover) diversity of these assemblages (
The alpha component of taxonomic diversity consists in the distinctiveness of taxa which measures the degree of taxonomic relatedness of species present in each sample, a reflection of the ecological and evolutionary mechanisms that have contributed to taxonomic composition (
Our understanding of taxonomic diversity of amphibians and reptiles in Mexico has been enriched by several studies.
Although in Mexico amphibians and reptile species have been documented as disappearing because of human activity such as habitat fragmentation, pollution, pet trade, invasive species, emerging diseases, and global warming, they are still the less well-studied vertebrate groups (
The study area consisted of different land cover/use types within the municipalities of Ahualulco de Mercado (main population 20°42'6.84″N, 103°58'24.96″W) and Teuchitlán (20°40'59.88″N, 103°50'51.72″W), both located in the west-central state of Jalisco, México (Fig.
A study area in Jalisco, Mexico B sampling points in the landscape. Sampling plots (C, D). Codes: sugar cane field (SCF), riparian habitat surrounded by crops (RH-C), cornfield (C), highly perturbed tropical dry forest (HPTDF), tropical dry forest (TDF), riparian habitat surrounded by tropical dry forest (RH-TDF), riparian habitat surrounded temperate forest (RH-TF), secondary vegetation surrounded by temperate forest (SV-TF), oak forest (OF) and pine-oak forest (POF) (modified after
The municipalities of Ahualulco de Mercado and Teuchitlán have similar territorial areas of 235.25 and 211.18 square kilometers, respectively. The two neighboring municipalities share a broad valley. The predominant land use types are agricultural and livestock activity, covering 60% of its surface, followed by secondary vegetation at 17% (
The RH-C land cover type is found between 1265 and 1270 m a.s.l. along a stretch of the Teuchitlán River. The dominant tree species were Salix humboldtiana, Fraxinus uhdei, Ficus insipida, Lysiloma acapulcense, Baccharis salicifolia, Salix taxifolia, Arundo donax and Scirpus californicus. One riverbank is used for crops, the other for recreational activities. HPTDF, with a high disturbance level, was found between 1200 and 1500 m a.s.l., and the dominant tree species were Acacia farnesiana, A. pennatula, Prosopis laevigata, and Pithecellobium dulce. The TDF was found between 1200 and 1700 m a.s.l. and included Bursera bipinnata, Ipomoea murucoides, L. acapulcense, Opuntia fuliginosa, and Tecoma stans as dominant species (
The RH-TDF had permanent streams. It was found between 1450 and 1750 m a.s.l. and was dominated by L. acapulcense, Lippia umbellata, Eysenhardtia polystachya and I. intrapilosa. The RH-TF had both permanent and temporal streams. It was located between 1500 and 1800 m a.s.l., and the dominant tree species were Salix bonplandiana, Quercus magnoliifolia, Q. splendens, Q. obtusata, Aiouea pachypoda, and Oreopanax peltatus (
We established circular diurnal (500 m2 each one) and rectangular nocturnal (10,000 m2) survey plots in each land cover/use type. The diurnal plots were separated 400 m of distance from each one. At each plot an intensive unrestricted visual search was carried out on the microhabitats preferred by these reptile species in each point count (i.e., logs and rocks). We recorded all individuals observed, and when possible, measured and photographed them. They were later released at the capture site. We conducted nine, monthly, samplings of the amphibian and reptile communities from July 2011 to August 2012 in TDF, RH-TDF, RH-TF, SV-TF, OF, and POF. Additionally, we surveyed both groups of taxa for eight months from September 2012 to September 2013 in SCF, RH-C, C, and HPTDF. Once a month during the day, we surveyed 12,500 m2 in TDF, RH-TDF, and RH-TF; 15,000 m2 in SCF, C, and HPTDF; 17,500 m2 in SV-TF; 25,000 m2 in OF and POF; and 22,500 m2 in RH-C. And at night we surveyed 10,000 m2 in each land cover/use type.
We included in the checklist all species whose presence within the study area or surroundings was confirmed by direct observation between August 2011 and December 2020. To corroborate a species’ identity, we took and deposited photographs in the Colección Herpetológica of the Museo de Zoología in the Facultad de Estudios Superiores Zaragoza, Universidad Autónoma de México. We followed
We generated monthly matrices of presence-absence of amphibian and reptile species. We determined sampling effort in each land/use type and the whole study area using sample-based rarefaction curves using the non-parametric estimators Chao 2, Jackknife 1, and Jackknife 2. All rarefaction curves were built using 10,000 randomizations without replacement. We performed these analyses using EstimateS 9.1.0 (
We measured the alpha component of taxonomic diversity by computing taxonomic distinctness. It takes into consideration the degree of taxonomic relatedness among species in each sample as a reflection of the ecological and evolutionary mechanisms that contribute to taxonomic composition (
We measured the beta component of taxonomic diversity by calculating and partitioned taxonomic beta into turnover (β.3) and differences in richness (βrich) components following
We recorded 20 species of amphibians and 39 of reptiles in the study area between August 2011 and September 2013. The average sampling effort for amphibians was 81.8% of representativity for the study area and that for reptiles, 80.5% (Fig.
Sample-based rarefaction curves for amphibians and reptiles generated using presence-absence data, showing observed and expected species for the different land cover/use types using non-parametric estimators. Codes: sugar cane field (SCF), riparian habitat surrounded by crops (RH-C), cornfield (C), highly perturbated tropical dry forest (HPTDF), tropical dry forest (TDF), riparian habitat surrounded by tropical forest (RH-TDF), riparian habitat surrounded temperate forest (RH-TF), secondary vegetation surrounded by temperate forest (SV-TF), oak forest (OF), pine-oak forest (POF), and number of species observed (Sobs).
Numerically, we recorded the lowest amphibian species richness in POF (three species) compared to the highest richness in HPTDF (eight), RH-C (nine), and RH-TDF (ten). Medium species richness was recorded in OF (five), TDF (five), RH-TF (six), CO (six), SCF (seven), and SV-TF (seven). In contrast, we recorded the lowest species richness for reptiles in RH-TF (five), CA (seven), C (seven), and POF (nine). SV-TF (18) had the highest richness. Medium species richness was registered in RH-TDF (10), OF (12), HPTDF (12), RH-C (13), and TDF (14).
The average taxonomic distinctness for amphibians and reptiles had all the ∆+ and Λ+ values within the probability funnels (p>0.05) (Fig.
The taxonomic beta diversity of amphibians and reptiles was high overall in both groups, being slightly higher in reptiles (βmulti = 0.70) than in amphibians (βmulti = 0.60). The turnover component (β.3 = 0.43 and β.3 = 0.32, respectively) was the most significant contributor to taxonomic differentiation in all comparisons. In turn, the two groups had a low contribution from the differences in richness component (βrich = 0.27 for reptiles and βrich = 0.27 for amphibians) (Fig.
Taxonomic beta diversity of amphibians and reptiles considering the turnover (β.3) and differences in richness (βrich) components by land cover/use types A total and B paired beta diversity of amphibians; and C total and D paired beta diversity of reptiles. Codes: sugar cane field (SCF), riparian habitat surrounded by crops (RH-C), cornfield (C), highly perturbated tropical dry forest (HPTDF), tropical dry forest (TDF), riparian habitat surrounded by tropical forest (RH-TDF), riparian habitat surrounded temperate forest (RH-TF), secondary vegetation surrounded by temperate forest (SV-TF), oak forest (OF) and pine-oak forest (POF).
In contrast, amphibians and reptiles had divergent patterns in regard to beta diversity (both turnover and richness differences) in pairwise comparisons between land cover/use types. Only POF and OF showed differences in richness in amphibians and reptiles without the turnover component (Fig.
For amphibians, the pairwise comparisons with the highest beta taxonomic diversity were between POF and SCF (0.92), POF and RH-C (0.86), and TDF and SCF (0.82), while the lowest were between RH-C and SCF (0.19), SV-TF and RH-TF (0.26), and RH-TF and TDF (0.35). The comparisons with the highest turnover were between SV-TF and C (0.69), SV-TF and SCF (0.81), RH-TF and SCF, and SV-TF and HPTDF (0.77 respectively) (Fig.
In relation to land cover/use types taxonomic beta diversity among reptiles was highest when comparing RH-TF and C (0.17), RH-TF and RH-C (0.54), and POF-C (0.11). The comparisons with the lowest values were POF-OF (0.21), HPTDF and RH-C (0.10), RH-TDF and TDF (0.20). The comparisons with the highest contribution of turnover component were between POF-C (0.11), RH-TF and C (0.17), and POF-SCF (0.05) comparisons, and for differences in richness component were between SV-TF and RH-TF (0.63), RH-TF and RH-C (0.54), and RH-TF-TDF (0.52). Similarly to amphibians, the comparison between POF-OF (0.21) was uniquely represented by differences in richness (Fig.
During nine years of observations, we recorded 20 species of amphibians belonging to 14 genera, nine families, and one order. The families with the highest species richness were Hylidae (seven species), Craugastoridae (three species) and Ranidae (three species). Ten of these species are endemic and under some protection category. Four species are under the Special Protection category, and one is under the Threatened category (
Checklist of amphibians and reptiles (August 2011 to December 2020) present in the various land/use types in a heterogenous landscape in west-central Mexico. Codes: sugar cane field (SCF), riparian habitat surrounded by crops (RH-C), cornfield (C), highly perturbed tropical dry forest (HPTDF), tropical dry forest (TDF), riparian habitat surrounded by tropical forest (RH-TDF), riparian habitat surrounded temperate forest (RH-TF), secondary vegetation surrounded by temperate forest (SV-TF), oak forest (OF), pine-oak forest (POF), endemic to Mexico (E), exotic (F), Special Protection (Pr), Threatened (A), Least Concern (LC), Near Threatened (NT), Vulnerable (VU), Endangered (EN), Low (L), Medium (M), High (H), records with distribution range extensions (*).
Taxonomic hierarchies and species | Common name | Endemism | Conservation status | SCF | RH-C | C | HPTDF | TDF | RH-TDF | RH-TF | SV-TF | OF | POF | Other land cover/use |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
AMPHIBIA | ||||||||||||||
Order Anura | ||||||||||||||
Craugastoridae | ||||||||||||||
Craugastor cf. hobarthsmithi (Taylor, 1937) | Smith’s pigmy tropical frog | E | EN, LC, L | X | X | X | X | |||||||
Craugastor occidentalis (Taylor, 1941) | Taylor’s Barking Frog | E | LC, M | X | X | X | X | X | X | X | ||||
Craugastor augusti (Dugès, 1879) | Barking Frog | LC, L | X | X | X | X | X | X | X | |||||
Eleutherodactylidae | ||||||||||||||
Eleutherodactylus sp. | X | X | X | X | X | X | ||||||||
Bufonidae | ||||||||||||||
Incilius occidentalis (Camerano, 1879) | Pine Toad | E | LC, M | X | X | X | ||||||||
Rhinella horribilis (Wiegmann, 1833) | Giant Marine Toad | L | X | X | X | X | ||||||||
Hylidae | ||||||||||||||
Exerodonta smaragdina (Taylor, 1940) | Emerald Tree Frog | E | Pr, LC, M | X | ||||||||||
Dryophytes arenicolor (Cope, 1866) | Canyon Tree Frog | LC, L | X | X | X | X | ||||||||
Dryophytes eximius (Baird, 1854) | Mountain Tree Frog | E | LC, M | X | X | |||||||||
Sarcohyla hapsa* Campbell, Brodie, Caviedes-Solis, Nieto-Montes de Oca, Luja, Flores-Villela, Garcia-Vazquez, Sarker & Wostl, 2018 | Northern Streamside Tree Frog | E | Pr, LC, L | X | ||||||||||
Smilisca baudinii (Duméril & Bibron, 1841) | Common Mexican treefrog | LC, L | ||||||||||||
Smilisca fodiens (Boulenger, 1882) | Lowland Burrowing Tree Frog | LC, L | ||||||||||||
Tlalocohyla smithii (Boulenger, 1902) | Dwarf Mexican Tree Frog | E | LC, M | |||||||||||
Leptodactylidae | ||||||||||||||
Leptodactylus melanonotus (Hallowell, 1861) | Black Jungle-Frog | LC. L | X | X | X | |||||||||
Microhylidae | ||||||||||||||
Hypopachus variolous (Cope, 1866) | Mexican Narrow-mouthed Toad | LC, L | X | |||||||||||
Phyllomedusidae | ||||||||||||||
Agalychnis dacnicolor (Cope, 1864) | Mexican Giant Tree Frog | E | LC, M | X | ||||||||||
Ranidae | ||||||||||||||
Rana cf. forreri (Boulenger, 1883) | Forrer’s leopard frog | Pr, LC, L | X | |||||||||||
Rana neovolcanica Hillis & Frost, 1985 | Transverse Volcanic Leopard Frog | E | A, NT, M | X | X | X | X | X | ||||||
Rana megapoda Taylor, 1942 | Big-footed Leopard Frog | E | Pr, VU, H | X | ||||||||||
Scaphiopodidae | ||||||||||||||
Spea multiplicate (Cope, 1863) | Mexican Spadefoot | LC, L | X | |||||||||||
REPTILIA | ||||||||||||||
Orden Squamata | ||||||||||||||
Anguidae | ||||||||||||||
Elgaria kingii Gray, 1838 | Arizona Alligator Lizard | Pr, LC, M | X | X | X | X | ||||||||
Anolidae | ||||||||||||||
Anolis nebulosus (Wiegmann, 1834) | Clouded Anole | E | LC, M | X | X | X | X | X | X | X | X | X | ||
Geckonidae | ||||||||||||||
Hemidactylus frenatus Duméril & Bibron, 1836 | Asian House Gecko | F | X | |||||||||||
Iguanidae | ||||||||||||||
Ctenosaura pectinata (Wiegmann, 1834) | Mexican Spinytail Iguana | E | A, H | X | X | X | X | X | X | |||||
Phrynosomatidae | ||||||||||||||
Sceloporus dugesii Bocourt, 1874 | Duges’ Spiny Lizard | E | LC, M | X | X | |||||||||
Sceloporus heterolepis Boulenger, 1895 | Dorsalkeel Spiny Lizard | E | LC, H | X | X | X | X | X | X | |||||
Sceloporus horridus Wiegmann, 1834 | Horrible Spiny Lizard | LC, M | X | X | X | X | X | |||||||
Sceloporus nelson Cochran, 1923 | Nelson’s Spiny Lizard | E | LC, M | X | ||||||||||
Sceloporus torquatus Wiegmann, 1828 | Torquate Lizard | E | LC, M | X | ||||||||||
Sceloporus spinosus Wiegmann, 1828 | Eastern Spiny Lizard | E | LC, M | X | ||||||||||
Sceloporus utiformis Cope, 1864 | Antesator | E | LC, H | X | X | X | X | X | ||||||
Urosaurus bicarinatus (Duméril, 1856) | Tropical tree lizard | E | LC, M | X | X | X | ||||||||
Phyllodactylidae | ||||||||||||||
Phyllodactylus lanei Smith, 1935 | Lane’s Leaf-toed Gecko | E | LC, H | X | ||||||||||
Scincidae | ||||||||||||||
Plestiodon dugesii (Thominot, 1883) | Duges’ Skink | E | Pr, VU, H | X | X | X | X | |||||||
Plestiodon callicephalus (Bocourt, 1879) | Mountain Skink | LC, M | X | X | ||||||||||
Teiidae | ||||||||||||||
Aspidoscelis costatus (Cope, 1878) | Western Mexico Whiptail | E | Pr | X | X | X | X | |||||||
Aspidoscelis communis (Cope, 1878) | Colima Giant Whiptail | E | Pr, LC, M | X | ||||||||||
Boidae | ||||||||||||||
Boa sigma (Smith, 1943) | Boa | A, LC, M | X | X | ||||||||||
Colubridae | ||||||||||||||
Masticophis mentovarius (Duméril, Bibron & Duméril, 1854) | Neotropical Whip Snake | E | LC, L | X | X | X | X | X | ||||||
Drymarchon melanurus (Duméril, Bibron & Duméril, 1854) | Blacktail Cribo | LC, L | X | X | X | X | ||||||||
Lampropeltis ruthveni* Blanchard, 1920 | Ruthvens Kingsnake | A, NT, H | X | X | X | X | ||||||||
Leptophis diplotropis (Günther, 1872) | Pacific Coast Parrot Snake | E | A, LC, H | X | ||||||||||
Masticophis bilineatus (Jan, 1863) | Sonoran Whipsnake | LC, M | X | |||||||||||
Oxybelis aeneus (Wagler, 1824) | Mexican Vine Snake | L | X | X | ||||||||||
Pituophis deppei (Duméril, 1853) | Mexican Bull Snake | E | A, LC, H | X | X | |||||||||
Senticolis triaspis (Cope, 1866) | Green Rat Snake | LC, L | X | X | ||||||||||
Sonora mutabilis Stickel, 1943 | Mexican Groundsnake | E | LC, H | X | ||||||||||
Tantilla bocourti (Günther, 1895) | Bocourt’s Black-headed Snake | E | LC, L | X | X | X | ||||||||
Trimorphodon tau Cope, 1870 | Mexican Lyre Snake | E | LC, M | X | X | |||||||||
Dipsadidae | ||||||||||||||
Diadophis punctatus (Linnaeus, 1766) | Ring-necked snake | LC, L | X | X | ||||||||||
Hypsiglena torquata (Günther, 1860) | Sinaloan Nightsnake | Pr, LC, L | X | |||||||||||
Imantodes gemmistratus* (Cope, 1861) | Central American Tree Snake | Pr, L | X | |||||||||||
Leptodeira maculata (Hallowell, 1861) | Southwestern Cat-eyed Snake | E | Pr, LC, L | X | ||||||||||
Leptodeira splendida Günther, 1885 | Splendid Cat-eyed Snake | E | Pr, LC, H | X | X | |||||||||
Rhadinaea Hesperia Bailey, 1940 | Western Graceful Brown Snake | E | LC, M | X | X | |||||||||
Rhadinaea taeniata (Peters, 1863) | Pine-Oak Snake | E | LC, M | X | ||||||||||
Elapidae | ||||||||||||||
Micrurus distans* Kennicott, 1860 | West Mexican Coral Snake | E | Pr, LC, H | X | X | X | ||||||||
Leptotyphlopidae | ||||||||||||||
Rena humilis Baird & Girard, 1853 | Western Blind Snake | LC, L | X | X | ||||||||||
Natricidae | ||||||||||||||
Thamnophis copei* (Dugès, 1879) | Cope’s mountain meadow snake | E | Pr, VU, H | X | ||||||||||
Storeria storerioides (Cope, 1866) | Mexican Brown Snake | E | LC, M | X | X | X | ||||||||
Thamnophis eques (Reuss, 1834) | Mexican Garter Snake | A | X | X | ||||||||||
Thamnophis melanogaster (Peters, 1864) | Blackbelly Garter Snake | E | A, LC, L | X | ||||||||||
Thamnophis cyrtopsis (Kennicott, 1860) | Black-necked Garter Snake | A, LC, L | X | X | X | |||||||||
Typhlopidae | ||||||||||||||
Indotyphlops braminus (Daudin, 1803) | Bootlace Snake | F | X | X | X | |||||||||
Viperidae | ||||||||||||||
Agkistrodon bilineatus Günther, 1863 | Cantil Viper | Pr, NT, M | X | X | X | |||||||||
Crotalus Basiliscus (Cope, 1864) | Basilisk Rattlesnake | E | Pr, LC, H | X | X | X | ||||||||
Crotalus triseriatus Wagler, 1830 | Western Dusky Rattlesnake | E | H | X | ||||||||||
Order Testudines | ||||||||||||||
Kinosternidae | ||||||||||||||
Kinosternon integrum Le Conte, 1854 | Mexican Mud Turtle | E | Pr, M | X | X | X |
We documented extensions in the known distribution range of Sarcohyla hapsa (Suppl.material
We recorded 48 species of reptiles belonging to 34 genera, 17 families, and two orders (Table
We documented extensions in the known distribution range of three species of reptiles. Lampropeltis ruthveni was observed in September 2011 in SV-TF (20°40'01"N, 103°52'23"W) (Suppl.material
Thamnophis copei is endemic to Mexico (Suppl.material
Imantodes gemmistratus was observed in September 2012 in HPTDF (20°41’,41"N, 103°50'33"W) (Suppl.material
We achieved high sampling efforts for both amphibians and reptiles at all sites, so the samples can be considered representative of both groups. Support for this assessment comes also from having recorded the same number of species of amphibians in another seven years of non-systematic surveys and species observations within the study area. In contrast, the number of species of reptiles increased from 39 to 48 species, the earlier systematic survey (August 2011 to September 2013) detected 81% of the reptile species present there.
Monitoring taxonomic diversity has been proposed as a tool to develop ecosystem management plans, ecological restoration projects, and the creation of protected areas (
Only the RH-C (five species) had higher taxonomic distinctiveness of amphibians than expected from the model. RH-TDF (ten species) and SCF (four species) had the highest alpha taxonomy diversity within the model. TDF did not have the highest alpha taxonomic richness against what we expected, even though it is recognized as a neotropical ecosystem with an important amphibian richness (23% of Mexican amphibians) (
Almost all the land cover/use types used by reptiles had a higher alpha taxonomic distinctiveness than the average within the model. These results suggest that reptiles can maintain high alpha taxonomic diversity even in heterogeneous landscapes. SCF (nine species), RH-C (14 species), and RH-TF (seven species) had the highest alpha taxonomic diversity within the model, and RH-TDF (eight species) and HPTDF medium ones (24 species). Agricultural systems can vary greatly in structure; uniform agroecosystems like monocultures exhibit shallow levels of biodiversity (
Factors that contribute to different components of beta diversity in amphibians and reptiles include the physiological limits of the species (βrich) and speciation processes (β.3), especially in taxa with low mobility (
For the region evaluated, the turnover component (β.3) contributed the most to taxonomic differentiation because of the configuration with abrupt changes in patches mentioned earlier. Because of the narrow distribution ranges of amphibians and reptiles, this is consistent with previous work (
Taxonomic beta diversity can also be expected to differ between groups with different evolutionary histories; notably, it has been reported that amphibians show higher taxonomic beta diversity due to dispersal limitations and their dependence on water bodies (
The relationship between alpha and beta taxonomic diversity remains poorly understood (
Although paired comparisons between the two groups reveal differences in beta diversity, we also documented common responses. In amphibians, the highest beta diversity occurred between conserved (POF, TDF) and disturbed (SCF, RHC) habitats. This reflects a high sensitivity to local disturbance, especially considering that this group was strongly influenced by the differences in richness component of beta diversity, as in the case of the comparison of POF with RH-C (one of the comparisons with the highest beta diversity). This indicates that despite shared taxa, supra-specific levels are aggregated to cause differences in richness between the paired comparisons. In the same way, in reptiles, we found that the comparisons with the highest beta diversity occurred between conserved (RH-TF, POF) and disturbed (C, RH-C) habitats, showing a consistent pattern with a predominance of the turnover component. This resulted from changes in the taxa set between these habitats. These results suggest that disturbance could become more important for taxonomic beta diversity of amphibians and reptiles than temperate vs. tropical conditions, given its high potential to threaten species and populations, acting more aggressively than the evolutionary history of species (
Our work found that the study area shelters 40.4% and 28.1% of Jalisco’s state amphibians (52 species) and reptiles (171 species), respectively (
Many of the recorded species (56.5%) in this heterogeneous landscape are endemic to Mexico. This was true for more than half of the species of reptiles, highlighting the area’s role in conserving existing native biodiversity. This could be due to its geographical position and the influence of the Trans-Mexican Volcanic Belt which, through the complexity of the landscape, promotes processes of speciation and endemism and is considered one of the most diverse zones in the country (
Knowing the local distribution of species is essential to monitor and manage local wildlife (
We found that the amphibian and reptile taxonomic diversity in the studied landscape results from i) remnants of native vegetation, even with some level of disturbance, ii) the existence of a heterogeneous matrix with different land cover/use types, albeit with a higher number of land cover types, iii) availability of water during the whole year in some of the land cover types, iv) connectivity between areas allowing the animals to move between different land cover/use types. Finally, the proximity of the study area to mountainous areas like La Primavera or Tequila Volcano is probably another factor to consider. These mountains are natural areas that harbor wildlife and that might act as species pools that could disperse to the study area.
Knowing the distribution of species at different spatial scales, having complete checklists, and analyzing diversity in its various facets at both alpha and beta levels are essentials for species management and conservation. Variation in alpha and beta taxonomic diversity presents a challenge for conservation strategies and management plans as they need to consider differences between sites. It is vital to consider endemic species, particularly those under conservation categories or those associated with native vegetation cover types with low disturbance, so management practices can encourage their presence and abundance. In this sense, preserving remaining natural forests and those with different levels of disturbance is necessary for conserving amphibian and reptile communities. Moreover, this study highlights the need for specific conservation strategies and recommendations to be integrated into broader landscape-level conservation planning. Nowadays, the great rate of land cover changes highlights the need to promote the existence of a connected heterogeneous landscape with different land cover/use types, thus enhancing the ability to conserve amphibians and reptiles. The other patches can offer shelter, water, and food permanently or temporarily. Even more, encouraging the connection among different land cover/use types will ensure that amphibians and reptiles can move between patches of this matrix.
We thank Uri Omar García Vázquez and Matias Domínguez Laso for helping as with the digital deposits of the species photographs in the Museo de Zoología in the Facultad de Estudios Superiores Zaragoza, UNAM. We are grateful to Leobardo Padilla Miranda and Ericka Blanco Morales (Centro Interpretativo Guachimontones Phil Weigand), Mónica Ureña Díaz (Ayuntamiento de Teuchitlán 2012–2015), Ricarda Orozco Wences (Restaurant Soky) and Edgar Lucke Gracián (Hacienda Labor de Rivera). We thank Jachar Aguirre, Alvaro Urzúa, Héctor Franz, Jesús Navarro, and Ramón Vázquez for their field assistance. We are grateful to Robert Cushman, Jocelyn Hudon, and the anonymous reviewers for their valuable comments and reviews which significantly improved the manuscript’s quality.
The authors have declared that no competing interests exist.
No ethical statement was reported.
Funding support for this research project were provided through Leobardo Padilla Miranda and Ericka Blanco Morales (Centro Interpretativo Guachimontones Phil Weigand), Mónica Ureña Díaz (Ayuntamiento de Teuchitlán 2012-2015), Ricarda Orozco Wences (Restaurant Soky) and Edgar Lucke Gracián (Hacienda Labor de Rivera).
Conceptualization: VCRE, FARZ, ALSP. Data curation: VCRE, AAGG, EAG, ALSP. Formal analysis: VCRE, EAG, ALSP. Investigation: VCRE, ALSP, EAG, AAGG. Methodology: FARZ, VCRE, ALSP, EAG, KEPJ, FMHM, LDP. Project administration: VCRE, ALSP. Writing-review and editing: VCRE, FMHM, KEPJ, FARZ.
Verónica Carolina Rosas-Espinoza https://orcid.org/0000-0001-8595-3203
Eliza Álvarez-Grzybowska https://orcid.org/0000-0003-3580-3869
Arquímedes Alfredo Godoy González https://orcid.org/0000-0002-6313-0238
Ana Luisa Santiago-Pérez https://orcid.org/0000-0001-7494-9129
Karen Elizabeth Peña-Joya https://orcid.org/0000-0002-7237-5894
Fabián Alejandro Rodríguez-Zaragoza https://orcid.org/0000-0002-0066-4275
Leopoldo Díaz Pérez https://orcid.org/0000-0003-0271-9257
Francisco Martín Huerta Martínez https://orcid.org/0000-0001-6923-3425
All of the data that support the findings of this study are available in the main text or Supplementary Information.
Supplementary information
Data type: docx
Explanation note: table S1. Sample-based rarefaction curves generated using presence-absence data for both amphibians and reptiles. We report observed and expected species by land cover/use type using non-parametric estimators. Codes: sugar cane field (SCF), riparian habitat surrounded by crops (RH-C), cornfield (C), highly perturbated tropical dry forest (HPTDF), tropical dry forest (TDF), riparian habitat surrounded by tropical forest (RH-TDF), riparian habitat surrounded temperate forest (RH-TF), secondary vegetation surrounded by temperate forest (SV-TF), oak forest (OF), pine-oak forest (POF) and number of species observed (Sobs). fig. S1. Species with the documented range extensions. A Sarcohyla hapsa B Lampropeltis ruthveni C Thamnophis copei D Imantodes gemmistratus in a heterogeneous landscape in west-central Mexico. All photos by Eliza Álvarez-Grzybowska, except B) by Aldo Dávalos Martínez. fig. S2. Records of Sarcohyla hapsa in Jalisco state (black triangles,