Abstract
A new species of palaeodictyopteridan insect, Heolus martinclosasi sp. nov., based on a partial wing, has been identified in the uppermost Pennsylvanian (Stephanian C local stage) deposits of the Castellar de N’Hug-Camprodon Basin, located in the Surroca-Ogassa coalfield within the Pyrenees of Catalonia, Spain. This species belongs to the Palaeodictyoptera, and is the first of this order described from the Paleozoic deposits of Spain. Heolus martinclosasi sp. nov. is the second species within the relatively small Heolidae family, originally described by Handlirsch in 1906, in the USA. This new species was found alongside remains of in situ fossil plants such as Calamites suckowii, Sphenophyllum oblongifolium, and marattialean tree ferns, all of which grew between river channels. This suggests that these insects possibly lived in lake-like, permanently inundated floodplain deposits.