"Os Gomphocerinae e (Orthoptera: Acrididae) Região Metropolitana de Belém-PA"

Abstract

The grasshoppers of the subfamilies Gomphocerinae and Acridinae are orthoptera with Nearctic and Neotropical distribution, being found from the south of the United States to Argentina. This work aims to contribute to the knowledge of these grasshoppers in the Metropolitan Region of Belém-PA, through inventories carried out in the municipalities of Belém, Ananindeua, Marituba, Benevides and Santa Bárbara do Pará. The collections were based on visual search with an entomological net during 90 minutes in selected localities in the aforementioned municipalities, considering open environments (pastures or shrublands) and closed environments (primary forest or old stands). The collected material was identified using dichotomous keys and by comparison with specimens from the Orthoptera collection of the Invertebrates collection of the Museu Paraense Emílio Goeldi. Six field trips (Aug-Oct/2006 - Jan-Mar/2007) were made to the municipalities of the Metropolitan Region of Belém and a total of 1029 specimens of grasshoppers were obtained. For the subfamily Gomphocerinae (n= 878) 5 species were recorded and for Acridinae (n= 151) 8 species. For the subfamily Gomphoceriae, up to 4 species of these locusts were recorded in the municipalities of Belém/Ananindeua, Marituba and Santa Bárbara do Pará, and for the municipality of Benevides 5 species; as for the subfamily Acridinae, 6 species were found in Belém/Ananindeua; in Benevides 2 species were recorded; Marituba up to 5 species and only 3 species in the municipality of Santa Bárbara do Pará. The species composition of grasshoppers in the Metropolitan Region of Belém is as follows: Gomphocerinae: Compsacris pulcher BOLIVAR, 1890, Orphulella concinnula (WALKER, 1870), Orphulella pelidna (BURMEISTER, 1838), Orphulella punctata (DE GEER, 1773) and Amblytropidia sp. ; Acridinae: Metaleptea adspersa (BLANCHARD, 1843), Eutryxalis filata filata REHN, 1944, Parorphula sp, Parorphula sp.l Orphula sp.l, Orphula sp.2, Orphula sp.3 and Orphula sp.4. The richness of grasshopper species of the subfamily Gomphocerinae in the Metropolitan Region of Belém is low (5 species), since 30 species are known to occur in the Amazon. The richness specific to the subfamily Acridinae, in the same study area, is considered high (8 species), because 8 species of this subfamily are known to occur in the Amazon region.