The origin of exceptionally rich fish communities harboured within the freshwater systems of southern Europe is usually explained by allopatric speciation due to a long isolation of water basins. On the other hand, hybridization events have been recorded in several fish species, but they role in the speciation of freshwater fishes in the Southern Europe has not received significant attention. Contrary to most species within the Leuciscidae family, the genus Delminichthys inhabits a geographically restricted area (middle and southern Dinarides) and consists of only four endemic species. This study analysed the population genetic structure and demographic history of each Delminichthys species as a contribution to the understanding of the evolutionary peculiarities in Dinaric water systems. The obtained results revealed pronounced mito-nuclear and nuclear-nuclear discordance, likely the result of incomplete lineage sorting, as well as nuclear introgression observed in the Ombla River population in southernmost Croatia. In addition to allopatric speciation, ancient hybridization might have played an important role in the evolutionary history of this genus. The origin of the genus Delminichthys can be dated back to the Oligocene/Miocene boundary, to a period of significant tectonic activity in the Mediterranean region, and its ancestor likely inhabited the region of the central Dinarides. Intrageneric divergences occurred in the lower Miocene and Pliocene. Similarly, as previously proposed for Delminichthys adspersus, traces of underground migrations were found among Delminichthys ghetaldii populations, implying adaptations to underground life to be characteristic for the genus. All Delminichthys species express high levels of genetic diversity, likely as a consequence of their old origin. Size of D. adspersus is currently decreasing, while the remaining three species appear stable.
Examining the distribution patterns of sympatric large carnivores provides critical insights into the roles of prey availability and human disturbances in shaping the landscape use of these key predators. The Thung Yai Naresuan (East) Wildlife sanctuary (TYNE) in western Thailand has been presumed to be a natural stronghold for tigers (Panthera tigris), leopards (Panthera pardus), and large ungulates, but little was known about their habitat relationships there. During April 2010–February 2012, camera trap surveys (n = 106 camera trap locations; n = 1817 trap nights) and sign surveys (n = 493 km of transects) were designed to systematically cover overlapping areas of 925 km2 and 1421 km2, respectively, to characterize and evaluate tiger and leopard distribution in TYNE. Occupancy modeling was used to estimate the potential environmental and anthropogenic factors that best explained habitats used by these large carnivores. The predictive model of tiger and leopard occupancy from surveys at the same sampling scale revealed similar relationships between limiting factors and space use. Camera surveys show that tigers are more likely than leopards to inhabit areas where gaur (Bos gaurus) and sambar (Cervus unicolor) are frequently found.. Sign surveys from across TYNE also indicated tiger distribution was characterized by the presence of large ungulates, as well by areas with high ranger patrol effort; leopard distribution was characterized by a higher occurrence of smaller barking deer (Muntiacus vaginalis) and wild boar (Sus scrofa), and by areas with low human disturbance. Our findings suggest that tigers and leopards have specific habitat preferences within the TYNE, with tigers showing a preference for areas with larger ungulates. In contrast, leopards are more likely to be found in areas with smaller prey. Human settlement areas and disturbance activities were identified as key factors influencing the distribution of both species, limiting their range to the central to the eastern part of the sanctuary.
