Jaime Buestán

Scione Walker, 1850, is a Neotropical genus initially proposed as a subgenus of Pangonia Latreille, 1802, monotypic for P. incompleta Macquart, 1846. Currently, Scione has 46 valid species and has an exclusively neotropical distribution. The genus has been little studied, and only two reviews have been published; one by Szilády in 1926 and another by Kröber in 1930. Here, we review the genus Scione. We provide redescriptions, diagnoses, updated distribution records, identification key for the females, illustrations and comments for each species, and, additionally, made available photographs of 81% of the type specimens of the species. Furthermore, we designate a neotype for S. costaricana Szilády, 1926 and propose the status of nomen dubium for five species (S. albohirta Kröber, 1930, S. huancabambae Kröber, 1930, S. minuta Szilády, 1926, S. picta Szilády, 1926, and S. punctata Szilády, 1926), we treat S. grandis Philip, 1943 as incertae sedis, we consider S. lurida Enderlein, 1925 as a revised synonym of S. aurulans (Wiedemann, 1830), and nine new species (S. falsibilineata sp. nov., S. longibeccus sp. nov., S. nigella sp. nov., S. philipi sp. nov., S. peruviana sp. nov., S. smithi sp. nov., S. tinajillas sp. nov., S. walkeri sp. nov., and S. wilkersoni sp. nov.) are described.

The Equatorial Pacific Region (EPR) in Ecuador is characterized by high rates of vegetation diversity, and rapid loss of vegetation cover due to anthropogenic pressures. In this study, general ecological aspects of the Tabanidae family, including richness, endemism, and seasonality, were evaluated. Analyses reveal that approximately 42% of the species recorded for Ecuador are present in the EPR, and out of the 84 species cataloged in the EPR, 6 are endemic, representing an endemism of 7.14%. Furthermore, it was established that tabanid populations in a coastal dry forest significantly increased their population density during the dry season, while decreasing during the wet season.

After 94 years after the last revision of the genus and after 22 years since the last species was named, we describe four new species of Scione from Ecuador and Peru: S. cooperi sp. nov., S. gertrudeae sp. nov., S. kroeberi sp. nov. and S. merianae sp. nov. We provide diagnoses, descriptions, photographs and discussions for each of the species.

The genus Pityocera Giglio-Tos is revised based on examination of external morphology and genitalia of type material and specimens from Brazilian and foreign institutions. Five currently valid species in three subgenera are recognized: P. (Elaphella) cervus (Wiedemann, 1828); P. (Pityocera) festai Giglio-Tos, 1896; P. (Pseudelaphella) nana (Walker, 1850); P. (Pseudelaphella) nigribasis Fairchild, 1964; P. (Pseudelaphella) patellicornis (Kröber, 1930). Five new species are described: P. (Pseudelaphella) barrosi Gorayeb & Krolow sp. nov. (Brazil: Mato Grosso do Sul); P. (Pseudelaphella) gorayebi Limeira-de-Oliveira & Krolow sp. nov. (Brazil: Maranhão, Tocantins and Bahia); P. (Pseudelaphella) pernaquila Gorayeb & Krolow sp. nov. (Brazil: Pará and Rondônia); P. (Pseudelaphella) rhinolissa Krolow & Henriques sp. nov. (Brazil: Pará, Maranhão, Tocantins, Rondônia, Mato Grosso, Goiás and Mato Grosso do Sul; Bolivia: Santa Cruz); P. (Pseudelaphella) ecuadorensis Buestán & Krolow sp. nov. (Ecuador: Manabí, Guayas, Santa Elena and Loja). We provide diagnosis, descriptions, redescriptions, distribution records, illustrations and discussion for all species, as well as a key for identification of species.

Worldwide information about Tabanidae is biased toward taxonomical research, which has been the main source of diversity data for this group of fl ies. In Ecuador, studies on horse fl ies have been irregular since the first descriptions of three Andean specimens in 1848. Catalogues, checklists and collections in national museums demonstrate that despite its size, Ecuador is at present the richest country in number of tabanids species in the Neotropics after Brazil, Colombia and Mexico, and has one of the highest numbers of species per unit area. The tabanofauna is predominantly shared with Colombia (62.6%), Peru (47%), Brazil (35.9%), Panama (35.4%), and Venezuela (30.3%) that have biogeographic areas in common with Ecuador. Endemism rate of this group is around 12.6%, with Diachlorus, Dicladocera, Esenbeckia, Eristalotabanus (monotypic), and Leucotabanus genera as the most representatives. We add new records of Tabanidae for the country. The genus Hemichrysops was recorded for first time. The number of species in Ecuador now totals 198. A catalogue of all Ecuadorian species is compiled with a localities-gazetteer. We also present and discuss for the first time, the distribution of well known horse fl ies species (Chrysops varians var. tardus, Dicladocera macula and Fidena rhinophora) using georeferenced localities and niche modelling analyses.