Onychogomphus costae in Andalusia, southern Spain - mapping an overlooked species (Odonata: Gomphidae)

摘要

Onychogomphus costae is an Ibero-Maghrebian endemic, which is rare in the Iberian Peninsula. This study updates its distribution in Andalusia, southern Spain, based on a targeted survey carried out in 2015-2017 and the compilation of all available records. The species appears to be more widespread than previously documented, with a core distribution along the river Guadalquivir and its tributaries in the province of Cordoba. The altitudinal distribution of Onychogomphus costae reflects its general preferences for permanent, seasonally flooding, lowland rivers. The period of most observations of adults stretches over two months from mid-May to mid-July. Factors likely to explain why the species has been overlooked in past decades are discussed. These include recording effort, habitat features, adult behaviour, larval ecology and general water quality.