First description of the male genitalia in a short-tailed whipscorpion (Arachnida: Schizomida), description of the female, and comments on pygidial glands and cuticular ultrastructure of Surazomus algodoal Ruiz & Valente, 2017.

The male genitalia of Surazomus algodoal Ruiz & Valente, 2017 are described. Since this is the first attempt to describe male genitalia in the schizomids, we propose new terminology to describe the sclerites of the male genital chamber in the order. We believe that the male genitalia may provide a large set of characters for taxonomic research in schizomids, as the female genitalia have proven to do. The setae and other cuticular structures were investigated using light and scanning electron microscopy (SEM). The female of S. algodoal is described for the first time, including the genitalia, and we highlight the sexual dimorphism present in the species. We also present descriptions of: 1) microtrichia, with respect to their presence/length/distribution, 2) cuticular sensilla, glandular openings and other cuticular structures, proposing new terminology, 3) setae of the pedipalpal trochanter and tarsus. Some changes on the terminology of setae of pedipalpal tibia are also given. These advances may be useful for description in other schizomids. The pygidial glands, mostly ignored in modern papers, were assessed and commented upon.

A new species from the eastern Amazon rainforest with lectotype designations and key for Brazilian Oxarthrius Reitter, 1883 (Coleoptera: Staphylinidae: Pselaphinae).

Oxarthrius spiculatus sp. nov. from the Brazilian Amazon is described. Major diagnostic features of male and female genitalia are illustrated. Female genitalia is described for the genus for the first time. The specimens of the new species were collected from bauxite mining area in the State of Par, Brazil where they seem to live in leaf litter. The distribution of the genus is covered and a key to the known Brazilian species is given. Additionally, the lectotype is designated for the Brazilian species Oxarthrius anthicoides (L.W.Schaufuss) and Oxarthrius bispinosus (Reitter).

On the Amazonian cricket Phalangopsis Serville, 1831 (Orthoptera: Grylloidea: Phalangopsidae): biology, morphology, and a new species.

Phalangopsis mimbypysara n. sp. is described from specimens collected in natural cavities in the region of Altamira and Vitória do Xingu, state of Pará, Brazil. Phalangopsis gaudichaudi Saussure, 1874 is considered nomen dubium. We provide new data about biology, distribution, habitat selection, morphology, and natural history of the genus Phalangopsis.

The first species of Cotithene Voss (Coleoptera: Curculionidae: Curculioninae) from Amazonian Brazil, with notes on its role as a pollinator of Evodianthus funifer (Poit.) Lindm. (Cyclanthaceae).

Cotithene gorayebi Valente, da Silva de Medeiros, sp. nov. is the first species of Cotithene Voss, 1940 described from the Amazonian forest in Brazil. The new species differs from other described species of Cotithene by its integument color pattern dissimilar between sexes and by the procoxal cavities separated by only a narrow septum in both male and female. It furthers differs by the unique morphology of male and female genitalia. A previously published key and phylogenetic matrix to Cotithene species were each modified to include the new species. The historical trajectory of host associations (inflorescences of Cyclanthaceae) in Cotithene is reanalyzed with the inclusion of the host of the new species. Previously known species are believed to be non-pollinators of various Cyclanthaceae; however, field observations of adults of the new species on inflorescences in anthesis of Evodianthus funifer (Cyclanthaceae) strongly suggest that this may be the first species of Cotithene known to play a role as a pollinator of Cyclanthaceae.

Description of a new species of Surazomus (Arachnida: Schizomida), with comments on homology of male flagellum and mating march anchorage in the genus.

Surazomus saturninoae sp. nov. is described from eastern Amazon. The male has a pentagonal flagellum, similar to those of three other species in the genus. These four species are herein gathered as the arboreus-group of Surazomus. We present a brief synopsis of chaetotaxy description in hubbardiines and several homology proposals for the flagellum of the species in the arboreus-group: the posterior lobes may be homologous to the lateral lobes of hubbardiine species with trilobed flagella; the setal brush with 4-5 setae on the posterior lobe may be composed of one Dl2 seta and enlarged lobular microsetae; the single, median posterior coupling pocket may be homologous to the pair of posterior pockets seen in other hubbardiines; the single, median anterior coupling pocket may be homologous to the pair of pockets on the anterior border of the flagellum seen in other hubbardiines. Based on the morphology of these pockets and the chelicerae within Surazomus, we discuss the anchoring mechanism during the mating march.