Description of the second species of Serraseius (Acari: Mesostigmata: Phytoseiidae) and adjustments of the concept of the genus

Until now, Serraseius Moraes, Barbosa and Castro was a monotypic genus represented by Serraseius caicara Moraes, Barbosa and Castro, found in a fragment of the Atlantic Forest of the state of São Paulo, southeastern Brazil. This paper describes the second species of the genus, Serraseius nordestinus Araújo and Oliveira sp. nov., found in a fragment of the Atlantic Forest of the state of Pernambuco, northeastern Brazil. The examination of the specimens of this new species led to a need to adjust the morphological concept of the genus, changing the interpretation of one of the dorsal shield setae from Z1 to S2 (hence changing the idiosomal pattern to 10A:7F/JV-3:ZV-3), including trumpet-shaped as an additional type of spermathecal calyx for species of the genus and the possibility to have S5 inserted in the unsclerotized cuticle.