RESUMO

Resumen En el presente estudio, los nichos trófico y bioclimático de Liolaemus annectens y L. etheridgei son evaluados. Ambas especies se distribuyen en la región andina del sur del Perú. La comparación interespecífica del nicho trófico reveló a Lygaeidae (Hemiptera) como presa fundamental de L. etheridgei, mientras que las presas fundamentales en la dieta de L. annectens fueron larvas de Lepidoptera, Araneae, Curculionidae (Coleoptera) y Lygaeidae. Asimismo, se observó un importante consumo de material vegetal en ambas especies, por lo que pueden considerarse omnívoras. Ambas especies presentaron una baja amplitud de nicho trófico, con una tendencia especialista de consumo de presas, y un bajo solapamiento de nicho trófico. En cuanto al nicho Grinnelliano, la evaluación y comparación de modelos de nichos ecológicos, permitieron identificar las áreas de mayor idoneidad para la sobrevivencia de estas especies. Estas se encuentran en áreas de Arequipa, Moquegua y Tacna para L. etheridgei y en Arequipa, Puno, y Cusco para L. annectens. Ambas especies mostraron una baja superposición de nicho ecológico, rechazando la hipótesis de que ocupan nichos idénticos.

Abstract In the present study, the trophic and bioclimatic niches of Liolaemus annectens and L. etheridgei are evaluated. Both species are distributed in the Andean region of southern Peru. Interspecific comparison of the trophic niche revealed Lygaeidae (Hemiptera) as a fundamental prey for L. etheridgei, while the fundamental preys in the diet of L. annectens were Lepidoptera larvae, Araneae, Curculionidae (Coleoptera), and Lygaeidae. Additionally, a significant consumption of plant material was observed in both species, indicating an omnivorous diet. Both species exhibited a narrow trophic niche breadth, with a specialist tendency in prey consumption and low trophic niche overlap. Regarding the Grinnellian niche, evaluation and comparison of ecological niche models allowed the identification of areas of highest suitability for the survival of these species. These include some areas in Arequipa, Moquegua and Tacna for L. etheridgei, and some areas in Arequipa, Puno and Cusco for L. annectens. Both species showed low ecological niche overlap, rejecting the hypothesis of identical niches.

RESUMO

This study describes the microhabitat use, daily activity pattern, and diet of Liolaemus etheridgei Laurent, 1998 in the El Simbral and Tuctumpaya Polylepis forests in Arequipa, Peru. El Simbral is a fragmented forest, whereas Tuctumpaya is unfragmented. Our results reveal that L. etheridgei shows no positive selection for any of the microhabitats we identified in Polylepis forests; on the contrary, it selects negatively against Polylepis trees and nonthorny bushes. The daily activity patterns indicate a bimodal pattern with peaks at 9:00-10:59 and 13:00-13:59 h. The diet of L. etheridgei consists mainly of plant material, and the most important animal prey category is Lygaeidae: Hemiptera, which is selected for positively. In particular, microhabitat selection varied for nonthorny bushes, which were selected negatively in the Tuctumpaya population but neither positively nor negatively in the El Simbral population. According to the proportions of plant material found, the L. etheridgei from El Simbral were found to be omnivorous, whereas the Tuctumpaya population was herbivorous. However, the percentage of plant material consumed in the El Simbral population was close to the critical value for herbivory-omnivory. We conclude that the three ecological aspects of L. etheridgei studied here are virtually identical in El Simbral and Tuctumpaya; therefore, this species is not affected significantly by the current fragmentation of forest.