Geographical distribution of Discocyrtus prospicuus (Arachnida: Opiliones: Gonyleptidae): Is there a pattern?

ACOSTA, L.E.; GUERRERO, E.L.

ZOOTAXA

MAGNOLIA PRESS

Lugar: Auckland; Año: 2011 vol. 3043 p. 1 - 24

1175-5326

The environmental constraints determining the distribution of the harvestman Discocyrtus prospicuus in Argentina and Uruguay are addressed. Habitat observations across the entire range (Rio de la Plata-Atlantic coast area; Córdoba sierras; northwestern Argentina) are provided. Previous published localities, depurated for accuracy, new records and bioclimatic predictors were used to characterize the species bioclimatic profile and to build predictive distributional models with Bioclim and Maxent algorithms. Relative importance of each bioclimatic variable in the final models is assessed. It was determined that D. prospicuus is primarily a gallery forest dweller, with preferred climate temperate to temperate-cold; variables related to thermic uniformity rank among the most influencing. Results consistently support the alleged yungas-mesopotamian disjunction; but the link between the Rio de la Plata and Córdoba sierras areas show disagreement between methods (predicted continuous with Bioclim, separate with Maxent). It is suggested that the need of constant air humidity (favoured in the core area by its closeness to large rivers and the seacoast) and competitive exclusion with congener D. testudineus may represent additional limiting factors. Some observations on the species tolerance to human activity are also given.