Distribution and life-history traits of Calathus cinctus Motschulsky, 1850 (Coleoptera: Carabidae) in Croatia, with distribution of closely related species

Abstract

Calathus cinctus Motschulsky, 1850 was only recently separated from the group Calathus melanocephalus (Linnaeus, 1758). C. cinctus has now been recorded for the first time in Croatia, along the temporary Krčić River situated beneath Mt. Dinara. However, revision of museum collections revealed that this species also occurs at other localities in Croatia, in the Alpine region and along the Adriatic coast. Its sister species C. melanocephalus, as the type species of the group, is widely distributed in Croatia, whereas C. mollis Marsham, 1802 is mostly restricted to the coastal region, with a few records from Alpine and Continental Croatia. The distribution range of C. cinctus overlaps with the distribution ranges of its sister species. Life-history traits were studied using pitfall traps in a karst region of Croatia, including eu-Mediterranean and sub-Mediterranean zones, in riparian and karst habitats, and on agricultural land. Based on goodness-of-fit criteria, the zero-inflated negative binomial model and negative binomial model best described the distribution of C. cinctus. For both models, there was a statistically significant difference between habitat types for activity density, indicating that C. cinctus has a preference for open habitats. It was recorded above a range of soil types (e.g. red, brown, sandy, cultivated), with sparse vegetation, suggesting that sufficient sun exposure is a more important requirement than soil type. The seasonal dynamics of C. cinctus differed between eu-Mediterranean and sub-Mediterranean zones, despite the rather close proximity of the studied localities. Geographical variability of seasonal activity was most likely due to differences in climate, altitude and the vicinity of the high mountain. Calathus cinctus populations in both zones were wing-dimorphic, with brachypterous specimens prevailing in both populations, indicating population stability.