ABSTRACT Species of two genera of the tribe Discocerinini from the Neotropics are reviewed with an emphasis on the fauna from Brazil. The two species, Orasiopa (Reymontopa ) mera (Cresson, 1939) and Pectinifer aeneus (Cresson, 1918), are described, illustrated and new occurrence data are provided. Phylogenetic relationships of these two genera into the tribe are discussed. To facilitate identification of these species, we have included diagnoses of the Discocerinini and both genera and have also provided an annotated key to the New World genera in this tribe. We have also provided illustrations, photographs, and scanning electron micrographs of external structures and of structures of the male terminalia for included species.

Scatellini was proposed by Wirth & Stone, 1956 and currently includes 242 described species in nine genera. The tribe has representatives in all biogeographic regions and about 70 species occur in the Neotropical Region. Prior to this study, only two species were recorded from Brazil: Scatella obscura and Limnellia itatiaia. In this paper, species of Scatellini from Brazil are reviewed with an emphasis on the fauna from southern Brazil, where six new species have been discovered and are described herein: Scatella praia, S. plaumanni, S. rara, Scatophila darrowae, S. dianneae, and S. prainha. To facilitate identification of the tribe and included genera and species, we have included diagnoses of these taxa and have also provided an annotated key to the Neotropical genera in Scatellini. We have also provided illustrations of structures of the male terminalia of all included species of the genus Scatophila.

Species of the shore-fly Parydra Stenhammar, 1844 from Brazil are reviewed with an emphasis on the fauna from southern Brazil, where one new species, Parydra arcuata sp. nov. - state of Paraná, municipality of Castro (8 km N, 24º45.3'S, 49º58.9'W) -, has been discovered and is herein described. To facilitate identification of species, we have included a diagnosis of the genus. We have also provided illustrations of structures of the male terminalia for all included species.

The species of Diphuia Cresson, 1944 are reviewed with an emphasis on the fauna from southern Brazil, where two new species have been discovered and herein are described: Diphuia antonina sp. nov. and Diphuia grandis sp. nov. All known species are placed into two species groups (the anomala and nitida groups), which are characterized, and a key to these species is included. To facilitate identification of species of this uncommon genus, we have included diagnoses of the genus and tribe Hecamedini and have also provided an annotated key to New World genera in the tribe and to the known species of Diphuia. We have also provided illustrations of structures of the male terminalia of all included species.The species from southern Brazil, including the new ones, are illustrated.

Redescrição do gênero Diopsosoma Malloch (Diptera, Periscelididae). Diopsosoma Malloch, 1932 e sua única espécie conhecida, D. primum Malloch, 1932 são redescritos. O gênero, embora facilmente reconhecível pela cabeça projetada lateralmente em pedúnculos oculares, é praticamente desconhecido. Por isso, apresenta-se sua redescrição em conjunto com breves redescrições de Periscelididae e da subfamília Periscelidinae. Chave para os gêneros de Periscelididae e fotomontagem do holótipo, talvez o único exemplar preservado da espécie, são fornecidas.

Diopsosoma Malloch, 1932 and its only included species, D. primum Malloch, 1932 are redescribed. While the genus is remarkable and easily recognized by its laterally elongate head that is produced into eyestalks, it is otherwise virtually unknown. To bring attention to this extraordinary fly we redescribe it within the context of brief descriptions of the family Periscelididae and subfamily Periscelidinae. We also provide an annotated key to the described genera of Periscelididae and a photographic montage of the holotype, which is perhaps the only preserved specimen of this genus and species.