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

Until now, Serraseius Moraes, Barbosa & Castro was a monotypic genus represented by Serraseius caicara Moraes, Barbosa & Castro, found in a fragment of the Atlantic Forest of the state of Sao Paulo, southeastern Brazil. This paper describes the second species of the genus, Serraseius nordestinus Araujo & 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.