We examined the seasonal patterns of physiology and biochemical composition in the rock-dwelling clausiliid land snail Albinariacaerulea in relation to its ecology, morphology and climatic data. We found that A. caerulea displayed significant seasonal changes in biochemical composition and enzyme activity, especially during aestivation. Sugars were catabolized early in aestivation, and proteins and lipids seem to be the primary metabolic substrates after sugar reserves were depleted. Atypical for aestivating land snails was the accumulation of lactate and LDH during the first weeks of aestivation, possibly suggesting that anaerobic pathways can provide additional energy. Moreover, mortality was not significantly higher during aestivation, fresh-mass differences between the aestivation and active period were not substantial and the rate of fresh-mass decline during aestivation was low. In addition, A. caerulea shows a series of morphological (thick white shell, strengthened and reflected apertural lips, thick epiphragm, internal lamellae, door-like clausilium) and behavioural (high aggregation) characteristics that support survival during adverse climatic conditions by preventing desiccation. We did not find a correlation of biochemical variables (except LDH) with climatic conditions. Yet, the biochemical variables, taken as a whole, are sufficient to distinguish the periods of aestivation and activity. The above suggest that the start of aestivation is primarily controlled by an endogenous component, and perhaps changes in the biochemical composition are a by-product of this component and not a direct response to climatic conditions. These results, in conjunction with the non-elevated mortality during aestivation, indicate that in this Albinaria population morphological, behavioural and physiological adaptations to the dry conditions of the climatically unpredictable Mediterranean-type ecosystems are in effect, and seem to ensure sufficient water and fuel reserves.

Land snails usually exhibit cycles of activity and dormancy (aestivation or hibernation). The transition between these two states is accompanied by a range of behavioural and physiological responses to ensure their survival under adverse environmental conditions. Furthermore, aestivation plays an important role in shaping species' distribution patterns. We examined the seasonal patterns in biochemical tissue composition in relation to aspects of behavioural ecology in three land snail populations: one mainland and one insular population of the widespread Helix aspersa and a population (sympatric with the latter) of Helix figulina, a congeneric species with a narrow and declining distribution. Helix figulina aestivates in underground borrows, while H. aspersa spends the summer under stones and may interrupt aestivation when conditions become favourable. Prior to aestivation H. figulina accumulates metabolic fuels, which it consumes later during summer, and at the same time loses substantial body water and increases lactate dehydrogenase (LDH) activity. The insular H. aspersa population follows a similar pattern (regarding metabolites and LDH activity), with the difference that water loss is limited. However, the mainland population of H. aspersa deviates from this model with energy metabolites and water levels showing little variation throughout the year, while LDH activity is reduced. These differences probably reflect the particular behavioural and physiological patterns adopted by each species. The specialist and range-restricted H. figulina shows a constant and more predictable seasonal pattern, which may be effective for surviving in its historical biogeographic range, but it seems to be more vulnerable to possibly changing environmental conditions. On the other hand the generalist and cosmopolitan H. aspersa adopts a more flexible pattern that compensates for the effects of adverse conditions during aestivation and permits a more effective exploitation of energy resources.

Anatolian mountains have played an important role in speciation and definition of biogeographical subregions and have been defined as “hotspots” of biodiversity. Because of its position and its long palaeogeographic and palaeoclimatic history, Anatolia acted in the past as a bridge or as a barrier for species' dispersal, providing natural pathways or acting as a vicariant agent, respectively. In this study we investigated the phylogeny and biogeography of a small fossorial snake, Typhlops vermicularis , in Anatolia, using formalin-preserved specimens and following a special protocol. We inferred phylogenetic relationships using partial 12S and ND2 sequences, and estimated divergence times of major lineages. Our mtDNA analysis revealed a hidden genetic diversity within Anatolian T. vermicularis . Four well-supported lineages occur within our sampled populations corresponding to respective refugia, which represent humid areas with dense forest vegetation in high altitude. The remaining populations, from the western and southeastern Anatolia, are almost genetically identical, representing a recent geographic expansion. A distributional disruption and a following allopatric fragmentation for T. vermicularis possibly resulted from climatic oscillations that occurred during the Miocene and Pliocene. We propose that extreme and sudden aridification led to distribution shrinkage of T. vermicularis , with genetic lineages surviving in refugia.