Seasonal dynamics and micro-climatic preference of two Alpine endemic hypogean beetles

• Published in: International journal of speleology Vol. 44; no. 3; pp. 239 - 249
• Main Authors: Mammola, Stefano, Piano, Elena, Giachino, Pier Mauro, Isaia, Marco
• Format: Journal Article
• Language: English
• Published: Bologna University of South Florida Board of Trustees, a public body corporate, having locations in Tampa, St. Petersburg, and Sarasota 01-09-2015; University of South Florida Libraries
• Subjects: Carabidae; Cholevidae; Coleoptera
• ISSN: 0392-6672; 1827-806X
• DOI: 10.5038/1827-806X.44.3.3

Hypogean beetles generally live in stable environments, characterized by constant temperature and high relative humidity. Changes in the underground microclimatic conditions generally induce local migrations of the beetles through the hypogean environment in search of suitable microhabitats. The researchers studied the seasonal dynamics and the micro-climatic preference of two Alpine endemic hypogean beetles -- Sphodropsis ghilianii (Coleoptera, Carabidae) and Dellabeffaella roccae (Coleoptera, Cholevidae) -- in the hypogean complex of Pugnetto. They surveyed the two species for one year, using baited pitfall traps and measuring temperature and humidity along the two main caves. They used logistic regression mixed models to relate the presence of the two species to several variables, namely microclimate, subjacency and cave length. In addition, we tested the attractive power of the bait on the two species. The thermic optimum for S. ghilianii was found to be around 7 degrees Celsius, with an increasing probability of finding the species in the vicinity of the cave entrance during summer, autumn and spring.