Convergencias y divergencias entre dos comunidades coprófagas de montaña europeas (Coleoptera, Scarabaeoidea)

We analyzed the altitudinal change in dung beetle species richness and the relative proportion of higher taxa, as well as the turnover in the type of distribution and range size of species in two mountain chains located at the two extremes of Europe (Western Rhodopes Mountains and the Iberian Central System). Both mountain ranges showed a clear substitution among higher taxa (Aphodiinae–Geotrupinae vs. Scarabaeidae) and species richness variation with the altitude was similar. We suggest that East European dung beetle assemblages are conditioned by a horizontal colonization process in which mountains had been reached in relatively recent geological time by elements coming from different latitudes. In spite of these convergences, Rhodopes dung beetle assemblages are characterized by a significantly lower proportion of narrowly distributed species and a lower relevance of Aphodiinae species in lowland places. Although these divergences can be partially attributed to the dissimilar sampling effort accomplished in both regions, we suggest that the low number on narrowly distributed species could be due to the different role of these two mountain zones as refuges during glaciar–interglaciar Pleistocene cycles. Key words: Scarabaeoidea, Dung beetles, Altitudinal variation, Rhodopes mountain range, Iberian Central System, Refuges.Compilando toda la información faunística disponible sobre los coleópteros coprófagos de dos zonas montañosas desconectadas, ubicadas a ambos extremos de Europa (los Rhodopes Occidentales y el Sistema Central Ibérico), hemos analizado el cambio altitudinal en la riqueza de especies, la modificación en la proporción relativa de los principales grupos taxonómicos implicados, así como el relevo en el tipo de distribución y el tamaño del rango geográfico de las especies implicadas. Ambas zonas de montaña muestran un patrón evidente de sustitución entre taxones de alto rango (Aphodiinae-Geotrupinae vs. Scarabaeidae) y también parecidas tasas de variación en la riqueza de especies con la altura. Sugerimos que las comunidades coprófagas del este de Europa están también condicionadas primordialmente por un proceso de colonización horizontal, en el cual las montañas serían colonizadas en periodos geológicos recientes por elementos procedentes de latitudes septentrionales. A pesar de estas convergencias, las comunidades de los Rhodopes se caracterizan por una significativa menor presencia de especies con rangos de distribución restringidos y una escasa relevancia de las especies de Aphodiinae en las zonas de menor altitud. Aunque estas divergencias pueden atribuirse parcialmente a diferencias en el esfuerzo de colecta realizado en ambas regiones, consideramos el escaso número de especies con distribución restringida estaría relacionado con el distinto papel ejercido por estas montañas como refugio durante los ciclos glaciares del Pleistoceno. Palabras clave: Scarabaeoidea, Escarabajos coprófagos, Variación altitudinal, Rhodopes, Sistema Ibérico Central, Refugios

The species of Scarabaeus Linnaeus (Coleoptera: Scarabaeidae) in Bulgaria and adjacent regions: faunal review and potential distribution

We compile the available georeferenced information on Bulgarian Scarabaeus species, including both bibliographic and natural history data to provide basic ecological and biogeographical information as well as maps of climatically favourable areas (potential distributions) for each one of the species. Scarabaeus species in Bulgaria seem to be generally distributed across low altitude areas mainly under warm temperate or Mediterranean conditions, although S. variolosus appears to be the species adapted to the warmest conditions and S. armeniacus inhabits areas of medium altitude. Our results indicate that it is necessary to carry out an extra survey effort in the northern lowlands, away the Stara Planina Mts. in order to validate current climatically suitable territories for some species. However, the recent land use transformations of these lowland areas, together with the general decline of roller dung beetle populations, suggest that this validation may not be possible

Convergences and divergences between two European mountain dung beetle assemblages (Coleoptera, Scarabaeoidea)

We analyzed the altitudinal change in dung beetle species richness and the relative proportion of higher taxa, as well as the turnover in the type of distribution and range size of species in two mountain chains located at the two extremes of Europe (Western Rhodopes Mountains and the Iberian Central System). Both mountain ranges showed a clear substitution among higher taxa (Aphodiinae-Geotrupinae vs. Scarabaeidae) and species richness variation with the altitude was similar. We suggest that East European dung beetle assemblages are conditioned by a horizontal colonization process in which mountains had been reached in relatively recent geological time by elements coming from different latitudes. In spite of these convergences, Rhodopes dung beetle assemblages are characterized by a significantly lower proportion of narrowly distributed species and a lower relevance of Aphodiinae species in lowland places. Although these divergences can be partially attributed to the dissimilar sampling effort accomplished in both regions, we suggest that the low number on narrowly distributed species could be due to the different role of these two mountain zones as refuges during glaciar-interglaciar Pleistocene cycles