A parasite without host: The first fossil pterygosomatid mite (Acari: Prostigmata: Pterygosomatidae) from French Lower Cretaceous amber

The oldest-known member of a small parasitic mite family Pterygosomatidae (Trombidiformes: Eleutherengona) was found in the Lower Cretaceous (Albian) amber locality of Archingeay-Les Nouillers in Charente-Maritime, France. The majority of the extant members of the family are obligate parasites of lizards, and only one genus of twelve, Pimeliaphilus TrägÃ¥rdh, 1905, is known to infest arthropods - kissing bugs, scorpions, beetles and cockroaches. The excellent preservation of the fossil, its 3D preparation and optical microscopy allowed for its detailed morphological study and direct comparison to extant pterygosomatids. The fossil undoubtedly belongs to the genus Pimeliaphilus, regarded as the earliest-derivative genus in the family. Morphological comparison suggests that the Cretaceous species could be parasitic on some of the many cockroach families described from Archingeay. The discovery of another fossil specimen or an extant larva of the same Pimeliaphilus sp. in association with its host would test our hypothesis.