Temporal and Spatial Variation in the Diet of the Endemic Lizard Gallotia galloti in an Insular Mediterranean Scrubland
نویسندگان
چکیده
—We analyzed 621 lizard fecal pellets to assess the diet of the endemic lizard Gallotia galloti (Lacertidae) throughout one year in the thermophilous scrubland, the most threatened habitat in the Canary Islands. Indicating the importance of frugivory, 98.1% of pellets contained seeds from fleshy-fruited plant species (8,028 seeds in total), and the fruit volume reached 47.5%. The Canarian endemic plants Rhamnus crenulata and Canarina canariensis were most important in frequency of occurrence and number of seeds found in pellets, respectively. Lizards were more frugivorous during the summer (63.0% of volume), and seasonal variation was associated with temporal changes in availability of ripe fleshy fruits. We detected microspatial differences in the consumption of fruits and plant material. Significant correlations were found between plant cover of each species and their respective consumption by lizards. Lizards consumed invertebrates throughout the year; Formicidae, Hemiptera, Coleoptera, and Hymenoptera were the most frequently consumed prey (76.5% of the animal prey items). Our results indicate that G. galloti is one of the most frugivorous lacertids studied. The high number of undamaged seeds removed by these lizards also implies an important role in the seed dispersal processes of many fleshy-fruited plant species from this
منابع مشابه
Phylogenetic relationships of the Canary Islands endemic lizard genus Gallotia (Sauria: Lacertidae), inferred from mitochondrial DNA sequences.
Phylogenetic relationships among species and subspecies of the Canary Island endemic lizard genus Gallotia are inferred based on nucleotide sequences of fragments of 12S ribosomal RNA and cytochrome b mitochondrial genes. The four morphologically established species have also been recognized at the molecular level. Relative affinities among species follow an eastern-western geographic transect....
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