SciELO - Scientific Electronic Library Online

 
vol.10 número2Composición morfológica y rendimientos de maíces nativos sin uso de agroquímicos en Chiapas, MéxicoAtributos físicos y fisiológicos de las semillas de café (Coffea arabica L) índice de autoresíndice de assuntospesquisa de artigos
Home Pagelista alfabética de periódicos  

Serviços Personalizados

Journal

Artigo

Indicadores

Links relacionados

  • Não possue artigos similaresSimilares em SciELO

Compartilhar


Siembra

versão On-line ISSN 2477-8850

Siembra vol.10 no.2 Quito Jul./Dez. 2023

https://doi.org/10.29166/siembra.v10i2.04479 

Original Article

Ecophysiological observations on the body temperatures of the anurans Dendropsophus bifurcus, Rhinella marina, and Scinax ruber from upper basin Amazon in northeastern Ecuador

Observaciones ecofisiológicas sobre las temperaturas de cuerpo de los anuros Dendropsophus bifurcus, Rhinella marina y Scinax ruber de la Cuenca Amazónica Alta en el noreste de Ecuador

Marco A. Altamirano-Benavides1  2 
http://orcid.org/0000-0002-3082-8103

Guillermo A. Woolrich-Piña3 
http://orcid.org/0000-0002-3421-7246

1 Universidad Central del Ecuador, Facultad de Ciencias Agrícolas. Jerónimo Leiton y Gatto Sobral S/N. Ciudadela Universitaria. C. P. 170521. Quito, Pichincha, Ecuador. aaltamirano@uce.edu.ec

2 Universidad Iberoamericana del Ecuador. Dirección de Investigación. Av. 9 de Octubre N25-12 y Colón. Quito, Ecuador. maltamirano@unibe.edu.ec

3 Tecnológico Nacional de México, Campus Zacapoaxtla. División de Biología, Subdirección de Investigación y Posgrado, Laboratorio de Zoología y Ecofisiología. Carretera Acuaco-Zacapoaxtla km. 8, Col. Totoltepec, Zacapoaxtla. C. P. 73680. Puebla, México. gwoolrich@live.itsz.edu.mx


Abstract:

Ectothermic inhabitants of tropical forests are subjected to constant environmental temperatures, which determine their passive thermoregulatory strategies. We observe these trends during the summer of 2017, in the anurans Dendropsophus bifurcus, Rhinella marina, and Scinax ruber, in a tropical rainforest from the Upper Amazon Basin of Ecuador. D. bifurcus and S. ruber showed a tendency to tigmothermy, whereas R. marina presented tendencies towards heliothermy. Body temperatures (Tbs) did not differ between D. bifurcus and R. marina, but S. ruber presented a lower Tb. Our results suggest that thermal environment is influencing different thermoregulatory strategies as tigmothermy and heliothermy of frogs and toads distributed in tropical environments at low elevation.

Keywords: Amazon; anurans; field body temperatures; thermoconformers; thermoregulation

Resumen:

Los ectotermos que habitan los bosques tropicales están sujetos a temperaturas ambientales constantes, lo cual determina que sus estrategias termoregulatorias sean pasivas. Estas tendencias termoregulatorias fueron observadas durante el verano del 2017 en los anuros Dendropsophus bifurcus, Rhinella marina y Scinax ruber, en un bosque tropical de la cuenca amazónica alta del Ecuador. Una tendencia a la tigmotermia se presentó en D. bifurcus y S. ruber, mientras que R. marina presentó tendencia hacia la heliotermia. Las temperaturas de cuerpo (Tbs) no difirieron entre D. bifurcus y R. marina, pero S. ruber mostró una baja Tb. Nuestros resultados sugieren que el ambiente termal influencia las diferentes estrategias termoregulatorias como la tigmotermia y la heliotermia en ranas y sapos distribuidos en ambientes tropicales de baja elevación.

Palabras clave: Amazonía; anuros; temperaturas de cuerpo en campo; termoconformistas; termoregulación

1. Introduction

Body temperature (Tb) is a critical ecophysiological variable affecting the performance of ectotherms because intrinsic aspects of ecology, behavior and physiology are sensitive to Tb (Huey, 1982; Huey & Stevenson, 1979), including reproduction (Adolph & Porter, 1993), foraging (Ayers & Shine, 1997), growth (Kingsolver & Woods, 1997), locomotion (Ojanguren & Brañta, 2000), and courtship (Navas & Bevier, 2001).

Ectotherms can exhibit heliothermy or tigmothermy, obtaining energy by direct exposure to the sun or by direct contact with the substrate, respectively (Garrick, 2008). Tigmothermy has been recognized for species living in tropical rainforests and nocturnal species (Belliure & Carrascal, 2002). For species living in forests, there is a thermal refuge on the effect of the surrounding climate, creating particular microclimate conditions (higher relative humidity and lower temperatures respect to open habitats that allows avoid overheating and dehydration (Gaudio et al., 2017). Thus, some tropical forest ectotherms appear to be relatively passive with respect to environmental temperatures and behave as thermoconformers (Huey & Webster, 1976; Kohlsdorf & Navas, 2006).

The Western Amazon basin (Ecuador, Perú, and Colombia) has the higher diversity of amphibian (Frost, 2023; Vigle, 2008). Near of the Ecuadorian Amazon there are published studies on herpetofauna for several locations. Duellman (1978), showed that the herpetofauna of Santa Cecilia, on the Río Aguarico, Province of Napo, is composed of 173 species; Lescure and Gasc (1986) compared the spatial distribution between assemblages of lizards and anurans along the Río Putumayo and Ampiyacu (Perú), Igaraparana (Colombia), and Santa Cecilia Ecuador); Almendáriz (1987) reported 101 species of amphibians and reptiles of the Province of Pastaza (Ecuador); Duellman and Mendelson (1995) reported 68 amphibian and 46 reptile species north of the Department of Loreto in the Amazonian Perú. Izquierdo et al. (2000) found 34 amphibian and 27 reptile species in the Province of Sucumbios (Ecuador); however, data on the thermal biology of ectotherms in this region are insufficient. We explored the basic thermal biology of three frogs and their ecological implications in northeastern Ecuador. We describe here below the relationships among Tb and microenvironmental temperatures (e.g., Huey & Slatkin, 1976).

2. Materials and Methods

2.1 Study area

Fieldwork was carried out on July 16th and 17th, 2017, in the surroundings of the Juri-Juri Kawsay Amazon Scientific Station, located in the Protected Forest of Oglán Alto, Arajuno Canton, province of Pastaza, Ecuador (77.688583°N, 01.324152°W, Datum WGS84, elevation 604 m) (Figure 1). The local vegetation is premontane pluvial forest characterized by emergent trees (e.g., Ceiba pentandra, Pachira insignis, Ficus perisiana, and Otoba parviflora, among others); as well as abundant mosses and liverworts in the leaves and branches of the arboreal and shrubby vegetation (Cerón Martínez et al., 2007). Mean annual temperature is 18-24 °C, and annual precipitation ranges between 4,000 and 8,000 mm per year (Cerón Martínez et al., 2007).

Figure 1 Map of study area. 

2.2 Study species

Dendropsophus bifurcus (Figure 2-A) is distributed from the northwestern part of the Amazon Basin in Colombia, Ecuador and northern Perú (Jungfer et al., 2010). The native range of Rhinella marina (Figure 2-B) extends from the East Andes to Central Amazonia (Acevedo et al., 2016) although they have established populations in Australia, Eastern Asia and several islands of the Caribbean and the Pacific, as the result of translocations by humans (Lever, 2001); Scinax ruber (Figure 2-C) is widely distributed throughout the Guianas and Amazonia (Fouquet et al., 2007).

Figure 2 Study species. 

2.3 Body temperature

We collected 11 D. bifurcus, 17 R. marina, and 37 S. ruber (listening and following the direction of their songs, or through direct search in potential microhabitats: e.g. along water reservoirs, on stems, leaves, leaf litter, and logs, principally), by hand from 1,800 to 2,300 h (all individuals were active at the time of capture). Immediately upon capture, we measured body temperature (Tb), holding tightly on the tarsi to carefully insert a thermocouple into the vent. Air temperature (Ta) was recorded by placing the thermocouple 1 cm above substrate where the individual was first seen, and substrate temperature (Ts) was measured touching the substrate where individual first observed to the nearest 0.1°C with a thermocouple type K connected to quick-reading digital thermometer (Fluke 51-II®). Tb, Ta, and Ts were recorded during the first 5 seconds of the thermometer reading. On both days, the frogs and toads collection preceded intense rains, at temperatures close to 25 °C and relative humidity around 80 %. All organisms that required a capture time > 1 min were excluded from the statistical analyzes.

2.4 Statistical analysis

We used linear multiple regression [MLR] and best subsets regression [BSR] analysis for selecting the variables of MLR by systematically searching through the different combinations of Ta and Ts and selecting the subsets of variables that best contribute to predicting Tb for each species. We used the values of R 2 by BSR as best criterion to establish tigmothermy or heliothermy tendencies: if R 2 was higher between Tb vs Ta it indicates heliothermy, but if R 2 is higher between Tb vs Ts is a tendency to tigmothermy. On the other hand, we use the value of the slopes generates by BSR to establish active thermoregulation, or passive thermoregulation (thermoconformers) tendencies: if Tb vs Ta- Ts is close to zero, the organisms are active thermoregulators. If the value of the slope between Tb vs Ta- Ts is close to one, the organisms are thermoconformers (criterion of Huey & Slatkin, 1976). We used ANOVA and Bonferroni t-test post-hoc to compare Ta and Ts with the three species. To test the difference in Tbs among species, we realized a covariance analysis [ANCOVA], using Ts as covariable.

3. Results

Means Tb, Ta and Ts for each species are detailed in Table 1. The best equations obtained by BMR that explained the thermal relationships were: Tb = 8.39 + 0.74 * Ts (R2 = 0.27, p > 0.05, n = 11); Tb = 4.79 + 0.86 * Ta (R2 = 0.51, p < 0.05, n = 17); and Tb = 2.14 + 0.96 * Ts (R2 = 0.71, p < 0.05, n = 37) for D. bifurcus, R. marina, and S. ruber, respectively.

Table 1 Mean Tb, Ta, and Ts for D. bifurcus, R. marina, and S. ruber from Juri-Juri Kawsay Amazon Scientific Station, province of Pastaza, northeastern Ecuador. Means are given ± 1 S.E. In brackets are the minimum and maximum temperatures. 

Thermoconformity tendencies are observed in the three species; tigmothermy tendencies are presented by D. bifurcus and S. ruber, and a heliothermy tendency is presented by R. marina. Ts did not present differences between species (ANOVA; F2,65 = 0.84, p > 0.05), while Ta presented significant differences for the three species (ANOVA; F2,65 = 11.39, p < 0.05; Table 2). We observed different Tbs among the species (ANCOVA with Ts as the covariate; F1,44 = 4.16, p < 0.05).

Table 2 Differences in Ta between the three species. All Pairwise Multiple Comparison Procedures (Bonferroni t-test). Overall significance level = 0.05. 

4. Discussion

Dendropsophus bifurcus.-- The mean Tb of D. bifurcus (25.2 ± 0.5 °C; 23.2 - 28.3; n = 11), was within the range of Tbs observed for other Dendropsophus species found at lower elevation, range from 24.8° to 25.8°C (Navas et al., 2013), but higher than those found in the mountain, range from 12.2° to 15.8°C (Navas, 1996). Considering our observations on the Tbs of D. bifurcus, we suggest that it is not different from the other congeners that inhabit tropical sites at low altitudes (≤ 90 m): D. ebraccatus (24.8 °C); D. microcephalus (25.8 °C), and altitude can be a limiting factor to reach Tbs greater than 20 °C: D. labialis (15.8 °C and 12.2 °C at 2,900 meters; 14.7 °C and 10 °C, at 3,500 meters; Navas et al., 2013). Considering the values of BMR, we suggest that D. bifurcus showed tendencies towards thermoconformity and tigmothermy (Huey & Slatkin, 1976).

Rhinella marina. -- The mean Tb for this species (25.8 ± 0.5 °C; 22.6 - 31.2; n = 17), is similar to other populations, range 24.2 - 27 °C, mean 25.2 °C; (Brattstrom, 1963). Under controlled conditions, at a humidity close to 80%, R. marina presented a similar Tb, which could indicate the optimal physiological for this species (Malvin & Wood, 1991). We observed that Tbs were higher than others congeners (R. spinulosa) distributed at different altitudes in the North, Center, and South of Chile: 19.8 °C, near to 2,469 meters; 20.7 °C, at 2,390 meters; and 20.3 °C, at 1,410 meters, respectively (Alveal-Riquelme, 2015); Rhinella arenarum (18.3 °C, around 730 meters) in Argentina (Sanabria et al., 2011); and Rhinella schneideri (20.8 °C, near to 630 meters) in Brazil (Noronha-de-Souza et al., 2015). However, these Tbs fell within the activity ranges, because below 13.7 °C and above 37.4 °C, their locomotion is limited (Kearney et al., 2008). BMR showed trends towards heliothermy and thermoconformity, this trend is similar in invasive populations inhabiting the tropical east coast of Australia (Seebacher & Alford, 2002).

Scinax ruber.-- The mean Tb in this study (23.2 ± 0.6 °C; 18.1 - 29.9; n= 37), was lower that observed for other population: 24.1°C, at 218 meters of elevation (Romero Barreto, 2013), but higher than S. fuscovarius and S. hiemalis distributed at higher altitudes, 22.5 °C, at 1,800 meters, and 12.5 °C, 1,200 meters, respectively (Navas & Araujo, 2000). Our results may suggest that altitude is a determining factor in the Tbs presented by different populations of Sinax frogs, observing a decline in Tbs with elevation at tropical latitudes (Andrews, 1998; Janzen, 1967). BMR showed trends towards tigmothermy and thermoconformity, a tendency similar to S. acuminatus and S. nasicus from Argentina (Novo, 2009).

Species comparison.-- Tbs observed in D. bifurcus, and R. marina were similar, contrary to S. ruber which had a significantly lower Tb. The locomotor performance dependent of Tb can explain these differences, since the best performance has been observed at Tbs close to the one presented by R. marina (Malvin & Wood, 1991), and other Scinax species in similar environments (Navas et al., 2008). In tropical forests, at low elevations, Tbs tend to be stable (Navas et al., 2008), thus the thermoconformity tendency of the three species can obey to variation of few degrees between the coldest and the warmest month in tropical latitudes (Janzen, 1967), shade forest environments (Huey, 1974), and high thermal quality reported for tropical environments (Vickers et al., 2011); while the tigmothermy tendency presented by D. bifurcus and S. ruber is characteristic of shade-dwelling organisms (Ruibal, 1961), and heliothermy presented by R. marina seems a strategy to avoid potential impacts of thermal stressor on physiology, ecology and survival (Narayan & Hero, 2014).

Our results suggest that thermal environment is influencing different thermoregulatory strategies, such as the tigmothermy and heliothermy of frogs and toads distributed in tropical environments at low elevation. Further studies are needed, specifically focused on the effect of both, deforestation at local scale, and climate change at regional scale on these thermoregulatory strategies and performance at different Tbs.

5. Conclusions

The observations on Tbs of D. bifurcus, show that it is not similar to the other congeners that inhabiting tropical sites at low altitudes (≤ 90 m), yet it is higher than the one observed for those from high altitudes (over 2,900 m elevation). Thus, the values of BMR, suggest that D. bifurcus present tendencies towards thermoconformity, and tigmothermy.

The mean Tb for R. marina was 25.8 ± 0.5 °C (22.6 - 31.2; n= 17); a similar Tb was exhibited under controlled conditions, at a humidity close to 80%, which could indicate the optimal physiologicalfor this species. Also, its mean Tb is higher than the one recorded within other populations at similar altitudes (600-700 m elevation), but in different geographical areas of South America. Moreover, the mean Tb of this toad is higher than others congeners distributed at altitudes over 1,410 meters. The values of BMR showed trends towards heliothermy, and thermoconformity.

The mean Tb for S. ruber in this study was 23.2 ± 0.6 °C (18.1 - 29.9; n= 37), being reduced than other population at lower elevations, but higher than other congeners distributed over 1200 meters of altitude. These results may suggest that altitude is a determining factor in the Tbs, observing a decline in temperatures with elevation at tropical latitudes. The values BMR showed trends towards tigmothermy and thermoconformity.

The Tbs observed in D. bifurcus, and R. marina were similar contrary to S. ruber which showed a Tb significantly lower. Thus, the thermoconformity tendency of the three species may obey mainly to variation of few degrees between the coldest and the warmest month in tropical latitudes; while the tigmothermy tendency presented for D. bifurcus and S. ruber is more characteristic of shade-dwelling organisms, and finally, heliothermy presented for R. marina seems a strategy to avoid potential impacts of thermal stressor on physiology, ecology, and survival.

Acknowledgement

We thank to Kichwa community Pablo López del Oglán Alto, especially Mrs. María Tanguila and Mr. Eliseo López for the assistance provided during this study at the Juri Juri Kawsay Amazon Scientific Station of the Universidad Central de Ecuador. To Fabiola Gandarilla-Aizpuru, Jesús A. Loc-Barragán, Enrique Lozano, Diego Arenas, Rufino Santos, Francisco Muñóz, and Raúl Trejo for their support in the field work. We are especially grateful to Rafael A. Lara-Reséndiz, Norberto Martínez-Méndez, Saúl F. Domínguez-Guerrero, Natalia Fierro-Estrada, Fausto R. Méndez-De La Cruz for their support in the field work and critical comments to improve this manuscript. We also thank to the Ministerio del Ambiente del Ecuador-Pastaza office for the research authorization AC-FAU-DPAP/MAE-2017-006.

Contributor Roles

Marco A. Altamirano-Benavides: conceptualization, investigation, methodology, funding acquisition, resources, project administration, writing - review & editing.

Guillermo A. Woolrich-Piña: investigation, formal analysis, methodology, validation, visualization, writing - original draft, writing - review & editing.

Ethical Issues

Research authorization AC-FAU-DPAP/MAE-2017-006 by Ministerio del Ambiente del Ecuador-Pastaza office.

Conflict of Interest

The authors declare that they have no affiliation with any organization with a direct or indirect financial interest that could have appeared to influence the work reported.

Funding

The funding was granted by the Belgian Development Cooperation through the Académie de Recherche et D'Enseignement Supérieur-Universidad Central del Ecuador (ARES-UCE), and by the Fondo de Investigaciones de la Universidad Iberoamericana del Ecuador.

References

Acevedo, A. A., Lampo, M., & Cipriani, R. (2016). The cane or marine toad, Rhinella marina (Anura, Bufonidae): two genetically and morphologically distinct species. Zootaxa, 4103(6), 574-586. 10.11646/zootaxa.4103.6.7 [ Links ]

Adolph, S. C., & Porter, W. P. (1993). Temperature, activity, and lizard life histories. The American Naturalist, 142(2), 273-295. 10.1086/285538 [ Links ]

Almendáriz, A. (1987). Contribución al conocimiento de la herpetofauna centroriental Ecuatoriana. Politécnica, 12(4), 77-133. http://bibdigital.epn.edu.ec/handle/15000/4778Links ]

Alveal Riquelme, N. F. (2015). Relaciones entre la fisiología térmica y las características bioclimáticas de Rhinella spinulosa (Anura: Bufonidae) en Chile a través del enlace mecanicista de nicho térmico. Universidad de Concepción. http://repositorio.udec.cl/jspui/handle/11594/1797Links ]

Andrews, R. M. (1998). Geographic variation in field body temperature of Sceloporus lizards. Journal of Thermal Biology, 23(6), 329-334. 10.1016/S0306-4565(98)00018-7 [ Links ]

Ayers, D. Y., & Shine, R. (1997). Thermal influences on foraging ability: body size, posture and cooling rate of an ambush predator, the python Morelia spilota. Functional Ecology, 11(3), 342-347. 10.1046/j.1365-2435.1997.00093.x [ Links ]

Belliure, J., & Carrascal, L. M. (2002). Influence of heat transmission mode on heating rates and on the selection of patches for heating in a mediterranean lizard. Physiological and Biochemical Zoology, 75(4), 369-376. 10.1086/342768 [ Links ]

Brattstrom, B. H. (1963). A Preliminary Review of the Thermal Requirements of Amphibians. Ecology, 44(2), 238-255. 10.2307/1932171 [ Links ]

Cerón Martínez, C. E., Reyes, C. I., Montalvo Ayala, C., & Vargas Grefa, L. M. (2007). La cuenca alta del río Oglán, Pastaza-Ecuador, diversidad, ecología y flora. Editorial Universitaria. [ Links ]

Duellman, W. E. (1978). The biology of an equatorial herpetofauna in Amazonian Ecuador. University of Kansas. [ Links ]

Duellman, W. E., & Mendelson, J. R. III. (1995). Amphibians and reptiles from northern Departamento Loreto, Perú: Taxonomy and biogeography. The University of Kansas Science Bulletin, 55, 329-376. 10.5962/bhl.part.779 [ Links ]

Fouquet, A., Vences, M., Salducci, M. D., Meyer, A., Marty, C., Blanc, M., & Gilles, A. (2007). Revealing cryptic diversity using molecular phylogenetics and phylogeography in frogs of the Scinax ruber and Rhinella margaritifera species groups. Molecular Phylogenetics and Evolution, 43(2), 567-582. 10.1016/j.ympev.2006.12.006 [ Links ]

Frost, D. R. (2023). Amphibian Species of the World: an Online Reference. Version 6.2. American Museum of Natural History. 10.5531/db.vz.0001 [ Links ]

Garrick, D. (2008). Body surface temperature and length in relation to the thermal biology of lizards. Bioscience Horizons: The International Journal of Student Research, 1(2), 136-142. 10.1093/biohorizons/hzn014 [ Links ]

Gaudio, N., Gendre, X., Saudreau, M., Seigner, V., & Balandier, P. (2017). Impact of tree canopy on thermal and radiative microclimates in a mixed temperate forest: A new statistical method to analyze hourly temporal dynamics. Agricultural and Forest Meteorology, 237-238, 71-79. 10.1016/j.agrformet.2017.02.010 [ Links ]

Huey, R. B. (1974). Behavioral thermoregulation in lizards: importance of associated costs. Science, 184(4140), 1001-1003. 10.1126/science.184.4140.1001 [ Links ]

Huey, R. B. (1982). Temperature, physiology, and the ecology of reptiles. In C. Gans, & F. H. Pough (eds). Biology of the Reptilia. Vol. 12, Physiology C. Physiological Ecology (pp. 25-91). Academic Press. https://carlgans.org/bor-view/?borv=12&borp=6Links ]

Huey, R. B., & Slatkin, M. (1976). Costs and benefits of lizard thermoregulation. The Quarterly Review of Biology, 51(3), 363-384. 10.1086/409470 [ Links ]

Huey, R. B., & Stevenson, R. D. (1979). Integrating thermal physiology and ecology of ectotherms: a discussion of approaches. American Zoologist, 19(1), 357-366. 10.1093/icb/19.1.357 [ Links ]

Huey, R. B., & Webster, T. P. (1976). Thermal biology of Anolis lizards in a complex fauna: the cristatellus group on Puerto Rico. Ecology , 57(5), 985-994. 10.2307/1941063 [ Links ]

Izquierdo, J., Nogales, F., & Yánez, A. P. (2000). Análisis herpetofaunístico de un bosque húmedo tropical en la Amazonia Ecuatoriana. Ecotrópicos, 13(1), 29-42. http://www.saber.ula.ve/handle/123456789/25506Links ]

Janzen, D. H. (1967). Why mountain passes are higher in the tropics. The American Naturalist , 101(919), 233-249. 10.1086/282487 [ Links ]

Jungfer, K. H., Reichle, S., & Piskurek, O. (2010). Description of a new cryptic southwestern Amazonian species of leaf-gluing treefrog, genus Dendropsophus (Amphibia: Anura: Hylidae). Salamandra, 46(4), 204-213. https://www.salamandra-journal.com/index.php/home/contents/2010-vol-46/222-jungfer-k-h-s-reichle-o-piskurekLinks ]

Kearney, M., Phillips, B. L., Tracy, C. R., Christian, K., Betts, A. G., & Porter, W. P. (2008). Modelling species distributions without using species distributions: the cane toad in Australia under current and future climates. Ecography ,31(4), 423-434. 10.1111/j.0906-7590.2008.05457.x [ Links ]

Kingsolver, J. G., & Woods, H. A. (1997). Thermal sensitivity of growth and feeding in Manduca sexta caterpillars. Physiological Zoology, 70(6), 631-638. 10.1086/515872 [ Links ]

Kohlsdorf, T., & Navas, C. A. (2006). Ecological constraints on the evolutionary association between field and preferred temperatures in Tropidurinae lizards. Evolutionary Ecology , 20, 549-564. 10.1007/s10682-006-9116-x [ Links ]

Lescure, J., & Gasc, J. P. (1986). Partage de l’espace foretier par les amphibians et reptiles en Amazonie du nord-ouest. Caldasia, 15(71-75), 707-723. https://revistas.unal.edu.co/index.php/cal/article/view/35362Links ]

Lever, C. (2001). The cane toad. The history and ecology of a successful colonist. Westbury Academic and Scientific Publishing. [ Links ]

Malvin, G. M., & Wood, S. C. (1991). Behavioral thermoregulation of the toad, Bufo marinus: effects of air humidity. Journal of Experimental Zoology, 258(3), 322-326. 10.1002/jez.1402580307 [ Links ]

Narayan, E. J., & Hero, J. M. (2014). Acute thermal stressor increases glucocorticoid response but minimizes testosterone and locomotor performance in the cane toad (Rhinella marina). PLoS ONE, 9, e92090. 10.1371/journal.pone.0092090 [ Links ]

Navas, C. A. (1996). Implications of microhabitat selection and patterns of activity on the thermal ecology of high elevation neotropical anurans. Oecologia, 108, 617-626. 10.1007/BF00329034 [ Links ]

Navas, C. A., & Araujo, C. (2000). The use of agar models to study amphibian thermal ecology. Journal of Herpetology, 34(2), 330-334. 10.2307/1565438 [ Links ]

Navas, C. A., & Bevier, C. R. (2001). Thermal dependency of calling performance in the eurythermic frog, Colostethus subpunctatus. Herpetologica, 57(3), 384-395. https://www.jstor.org/stable/3893104Links ]

Navas, C. A., Carvajalino-Fernández, J. M., Saboya-Acosta, L. P., Rueda-Solano, L. A., & Carvajalino-Fernández, M. A. (2013). The body temperature of active amphibians along a tropical elevation gradient: patterns of mean and variance and inference from environmental data. Functional Ecology , 27(5), 1145-1154. 10.1111/1365-2435.12106 [ Links ]

Navas, C. A., Gomes, F. R., & Carvalho, J. E. (2008). Thermal relationships and exercise physiology in anuran amphibians: Integration and evolutionary implications. Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology, 151(3), 344-362. 10.1016/j.cbpa.2007.07.003 [ Links ]

Noronha-de-Souza, C. R., Bovo, R. P., Gargaglioni, L. H., Andrade, D. V., & Bícego, K. C. (2015). Thermal biology of the toad Rhinella schneideri in a seminatural environment in southeastern Brazil. Temperature, 2(4), 554-562. 10.1080/23328940.2015.1096437 [ Links ]

Novo, M. J. K. B. (2009). Thermal tolerance and sensitivity of amphibian larvae from paleartic and neotropical communities. Universidade de Lisboa. http://hdl.handle.net/10451/1416Links ]

Ojanguren, A. F., & Brañta, F. (2000). Thermal dependence of swimming endurance in juvenile brown trout. Journal of Fish Biology, 56, 1342-1347. 10.1111/j.1095-8649.2000.tb02147.x [ Links ]

Romero Barreto, P. G. (2013). Requerimientos fisiológicos y microambientales de dos especies de anfibios (Scinax ruber e Hyloxalus yasuni) del bosque tropical de Yasuní y sus implicaciones ante el cambio climático. Pontificia Universidad Católica del Ecuador. http://repositorio.puce.edu.ec/handle/22000/5726Links ]

Ruibal , R. (1961). Thermal relations of five species of tropical lizards. Evolution, 15(1), 98-111 10.1111/j.1558-5646.1961.tb03132.x [ Links ]

Sanabria, E. A., Quiroga, L. B., & Martino, A. L. (2011). Seasonal changes in the thermal tolerances of the toad Rhinella arenarum (Bufonidae) in the Monte Desert of Argentina. Journal of Thermal Biology, 37(6), 409-412. 10.1016/j.jtherbio.2012.04.002 [ Links ]

Seebacher, F., & Alford, R. A. (2002). Shelter microhabitats determine body temperature and dehydration rates of a terrestrial amphibian (Bufo marinus). Journal of Herpetology , 36(1), 69-75. 10.1670/0022-1511(2002)036[0069:SMDBTA]2.0.CO;2 [ Links ]

Vickers, M., Manicom, C., & Schwarzkopf, L. (2011). Extending the cost-benefit model of thermoregulation: high-temperature environments. The American Naturalist , 177(4), 452-461. 10.1086/658150 [ Links ]

Vigle, G. O. (2008). The amphibians and reptiles of the Estación Biológica Jatun Sacha in the lowland rainforest of Amazonian Ecuador: a 20-year record. Breviora, 514(1), 1-30. 10.3099/0006-9698-514.1.1 [ Links ]

Received: March 28, 2023; Revised: July 10, 2023; Accepted: August 02, 2023

Corresponding author: Marco Antonio Altamirano-Benavides (aaltamirano@uce.edu.ec)

Creative Commons License Esta obra está bajo una Licencia Creative Commons Atribución-NoComercial 4.0 Internacional.