Pierre Moret

Biodiversity patterns and continental insularity in the tropical High Andes

Abstract Alpine areas of the tropical Andes constitute the largest of all tropical alpine regions worldwide. They experience a particularly harsh climate, and they are fragmented into tropical alpine islands at various spatial scales. These factors generate unique patterns of continental insularity, whose impacts on biodiversity remain to be examined precisely. By reviewing existing literature and by presenting unpublished data on beta-diversity and endemism for a wide array of taxonomic groups, we aimed at providing a clear, overall picture of the isolation-biodiversity relationship in the tropical alpine environments of the Andes. Our analyses showed that (1) taxa with better dispersal capacities and wider distributions (e.g., grasses and birds) were less restricted to alpine areas at local scale; (2) similarity among communities decreased with spatial distance between isolated alpine areas; and (3) endemism reached a peak in small alpine areas strongly isolated from main alpine islands. These results pinpoint continental insularity as a powerful driver of biodiversity in the tropical High Andes. A combination of human activities and warming is expected to increase the effects of continental insularity in the next decades, especially by amplifying the resistance of the lowland matrix that surrounds tropical alpine islands.

Climate warming effects in the tropical Andes: first evidence for upslope shifts of Carabidae (Coleoptera) in Ecuador

In order to assess the impact of global warming on the biodiversity of the tropical high Andean páramo ecosystem, we compared historical and recent surveys of ground beetle communities along elevational gradients of the Pichincha volcano (Northern Ecuador). The studied datasets date to 1880, 1985/86 and 2013/15. From 1880 to 1985, the bottom range of at least one stenotopic and wingless high‐altitude species, Dyscolus diopsis, has shifted approximately 300 m upward, with the resulting area reduction of more than 90% from >12 km2 to <1 km2, which highlights the probability of future local extinctions on the Pichincha as well as on other mountains of Ecuador. Over a shorter period of time, the comparison of the 1985/86 and 2013/14 datasets indicates that the lower limit of the superpáramo ground beetle community has shifted upwards from circa 4300 m to circa 4400 m. Different individual responses are recorded among the species. Some of them did not experience any significant change, whereas the upper limit of one of the grassland generalists has shifted upwards at least 400 m in 28 years. These results suggest that the response to global warming varies from one species to the other, depending on their degree of specialisation and tolerance. They call for the implementation of a monitoring programme that would use carabid assemblages as an indicator of the impact of climate change on the páramo ecosystem, in combination with other proxies.

Le peuplement du Bas Segura de la protohistoire au Moyen Âge (prospections 1989-1990)

Entre 1989 y 1990 un equipo hispano-frances emprendio una prospeccion al objeto de estudiar la dinamica y la organizacion del poblamiento en una region que fue durante mucho tiempo una encrucijada privilegiada. La investigacion geomorfologica desarrollada en colinas, dunas costeras y llanuras aluviales (la zona mas transformada desde la Edad Media) permite reconstruir la fisonomia antigua de la region. Desde la Edad del Bronce a la epoca islamica se observa una tendencia a la concentracion del poblamiento en las margenes del valle del rio Segura, pareja al despoblamiento de los macizos montanosos que no estan orientados hacia la llanura aluvial, al tiempo que los yacimentos se ocupan de forma discontinua.

Balligratus , new genus of wingless ground beetles from equatorial Andean montane forest (Coleoptera: Carabidae: Lachnophorini)

A new carabid beetle genus, Balligratus gen. nov., belonging to the tribe Lachnophorini, is described. It is geographically restricted to the equatorial Andes, and ecologically linked to the montane pluvial forest ecosystem, at elevations ranging from 1,200 to 3,600 m. As other carabid lineages that have radiated in such environments, Balligratus gen. nov. is a wingless clade, characterized by the loss of flight wings associated with metathoracic reduction, constriction of the elytral base, and reduced eye size. This evolution is unique among Lachnophorini. Four new species are described, all of them from Ecuador: Balligratus brevis sp. nov., Balligratus globosus sp. nov., Balligratus gracilis sp. nov. and Balligratus humerangulus sp. nov.