The Republic of San Marino is a tiny nation, completely surrounded by Italian territories. Despite its very small dimensions (only 61,19 square kilometers), it is inhabited by several amphibian species, including the Italian cave salamander Speleomantes italicus. The Republic of San Marino has a strong touristic and industrial vocation, and largely consist of urbanized areas. Therefore, it is reasonable to assume that the population of Italian cave salamanders occurring in San Marino will diverge from the population inhabiting natural areas. 

In 2022,  Dr. Casali and co-authors tested the hypothesis, presenting their results in a paper that whas recently been published on Acta Herpetologica. Conducting surveys in Spring and in Autumn, the authors collected 67 individuals of Speleomantes italicus from urban habitats. Each salamander was sexed, measured and subjected to  stomach content analysis. A total of 1018 prey items were retrieved and identified at the order or family level. Surprisingly, the diet composition exhibited anomalies compared to the broader species pattern.

While generally Speleomantes italicus favors flying insects, the San marino populations consumed less than 20% of such prey. On the other hand, the studied populations strongly rely on Entomobryomorpha (about ¼ of the overall consumed prey), but the authors note that this finding might be biased by prey availability during the sampling periods. 

In spite of the relatively small sample size and of the limited number of survey performed, this study - the first describing the trophic niche of Speleomantes italicus in the Republic of San Marino - serves as an intriguing starting point for further investigation, aimed at exploring possible explanation to the observed dietary anomalies.

Click here to read the full paper.

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