Rediscovery of the ghost bush-cricket Roeseliana oporina (Orthoptera: Tettigoniidae) in Central Spain

Roeseliana oporina (Bolivar in An Soc Esp Hist Nat 16:86–114, 1887), the ghost bush-cricket, became a mystery shortly after its original description in Central Spain. There was initial confusion about its type locality, original collector and failure to locate the species in 1890. More than 50 years after, the type specimens of Platycleis oporina were revised, but damage of the terminal segments of the male type prevented further taxonomic discussions. Since then the species was treated as “incertae sedis” and subsequently ignored. We recently rediscovered a living population of R. oporina near the type locality. The specimens found permitted the evaluation of its taxonomic status and to validate the veracity of the earlier findings. The morphological characters of the adult specimens fit precisely those of Bolivar’s description and match those of the type specimens. General appearance of R. oporina resembles that of R. azami and R. roeselii. However, the shape and distribution of spines on the branches of titillators, allow for a clear distinction from R. azami as well as from all other European species of Roeseliana. The known distribution of R. oporina is very restricted and subjected to intense man-made alterations, mostly due to the lack of knowledge of the presence of the species and the subsequent absence of conservation management. From a conservation perspective, it is important to declare “Critically Endangered-Possibly Extinct” species not seen for years, because ignoring them, or simply treating them as fully extinct not only will discourage searchers, but will facilitate the opening for development of habitat where the species could have been present, as was the case for R. oporina.