Possibly Oxfordian (Upper Jurassic) cockroach assemblage (Insecta: Blattaria) from the Phra Wihan Formation in Thailand

The Jurassic is the most explored time period regarding the cockroach fossil record, with roughly 15,000 cockroach specimens already collected. Here we report a new assemblage from the Phra Wihan Formation of Thailand comprising four new species: Falcatusiblatta kohringi sp. n. ( n = 17), Raphidiomima predlzena sp. n. ( n = 1), Elisamoides cudak sp. n. ( n = 2) and Praeblattella krzeminskii sp. n. ( n = 1). The composition of this assemblage suggests the Upper Jurassic age (contemporaneous with the Karatau Lagerstätte in Kazakhstan), confirmed with the presence of predominantly Oxfordian spinicaudatan, Pseudograpta Novojilov, 1954, although, a Middle Jurassic age cannot be excluded. The low diversity of cockroach fossils encountered is surprising considering the tropical position of ancient Thailand. The taphocoenosis only contains disarticulated wings while mutations expressed as vein deformities are extremely rare.