The comparative mitogenomics and phylogenetics of the two grouse-grasshoppers (Insecta, Orthoptera, Tetrigoidea)

OBJECTIVE: This study aimed to reveal the mitochondrial genomes (mtgenomes) of Tetrix japonica and Alulatettix yunnanensis, and the phylogenetics of Orthoptera species. METHODS: The mtgenomes of A. yunnanensis and T. japonica were firstly sequenced and assembled through partial sequences amplification, and then the genome organization and gene arrangement were analyzed. Based on nucleotide/amino acid sequences of 13 protein-coding genes and whole mtgenomes, phylogenetic trees were established on 37 Orthoptera species and 5 outgroups, respectively. RESULTS: Except for a regulation region (A+T rich region), a total of 37 genes were found in mtgenomes of T. japonicaand A. yunnanensis, including 13 protein-coding genes, 2 ribosomal RNA genes, and 22 transfer RNA genes, which exhibited similar characters with other Orthoptera species. Phylogenetic tree based on 13 concatenated protein-coding nucleotide sequences were considered to be more suitable for phylogenetic reconstruction of Orthoptera species than amino acid sequences and mtgenomes. The phylogenetic relationships of Caelifera species were Acridoidea and Pamphagoidea > Pyrgomorphoidea > Pneumoroidea > Eumastacoidea > Tetrigoidea > Tridactyloidea. Besides, a sister-group relationship between Tettigonioidea and Rhaphidophoroidea was revealed in Ensifera. CONCLUSION: Concatenated protein-coding nucleotide sequences of 13 genes were suitable for reconstruction of phylogenetic relationship in orthopteroid species. Tridactyloidea was a sister group of Tetrigoidea in Caelifera, and Rhaphidophoroidea was a sister group of Tettigonioidea in Ensifera.

Flutuação populacional de gafanhotos na Floresta Nacional de Chapecó, Santa Catarina / Grasshopper Population fluctuation in the National Forest of Chapeco, Santa Catarina

Com o objetivo de verificar a flutuação populacional de gafanhotos na Floresta Nacional de Chapecó (FLONA), em Santa Catarina, foram realizadas coletas semanais durante o período de dezembro de 2003 a dezembro de 2004 com armadilhas do tipo pit-fall, rede de varredura, guarda-chuva entomológico e malaise. Os picos populacionais para a maioria das espécies ocorreram durante os meses de dezembro, janeiro e fevereiro. A análise de regressão (5 por cento) apontou relação significativa entre os fatores climáticos e os níveis populacionais de Allotruxalis gracilis (Giglio-Tos, 1897), Parorphula graminea Bruner, 1900, Rhammatocerus brunneri (Giglio – Tos, 1895) e Xyleus discoideus discoideus (Serville, 1831).

In order to verify the grasshopper population dynamics in the National Forest of Chapecó, SC., weekly collections were made between December 2003 and December 2004, using pit-fall traps, sweep nets, entomological umbrellas and malaises traps. The population peaks for most of the species was reached in December, January and February. The regression analysis (5 percent) showed significant relation between the climatic factors and the population levels of Allotruxalis gracilis (Giglio-Tos, 1897), Parorphula graminea Bruner, 1900, Rhammatocerus brunneri (Giglio – Tos, 1895) and Xyleus discoideus discoideus (Serville, 1831).