The present research describes the histology of the midgut, gastric caeca, and pyloric valve of Tropidacris collaris (Stoll, 1813), (Orthopetera: Romaleidae). We used light microscopy, staining (Gomori's trichrome and periodic acid-Schiff (PAS)), and a routine histological analysis method (hematoxilin-eosin). The insects were obtained from, and also bred in, the Laboratory of Entomology, Department of Biology, of the Rural Federal University of Pernambuco (UFRPE). The collected material was fixed in alcoholic Boüin and embedded in paraplast. The results demonstrated that the midgut wall is composed of an inner epithelial layer and two outer layers of striate muscles: one internal (circular) and the other external (longitudinal), with connective tissue between the muscle fibers. The epithelium is single-layered, with two cell types: regenerative and elongated columnar. The gastric caeca presents muscle layers similar to those of the midgut. Simple columnar epithelium lines the gastric caeca, which presents villi and projects towards the lumen. The pyloric valve is of striate muscle tissue, covered by a single epithelial-cell layer.

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Neotropical Entomology 34(4): 585-591 (2005) Pathogenicity of Metarhizium anisopliae var. anisopliae and Metarhizium anisopliae var. acridum on Nasustitermes coxipoensis (Holmgren) (Isoptera: Termitidae)ABSTRACT -The action of Metarhizium anisopliae var. anisopliae and Metarhizium anisopliae var. acridum on the mound termite Nasutitermes coxipoensis (Holmgren) and the conidia production on dead insects were studied in laboratory. Infective doses were determined through direct contact of the insects with the fungi cultures with 12 days of growth followed by conidia quantification in Neübauer camera. The doses of 0.5 x 10 6 and 1.6 x 10 7 conidia/ml of M. anisopliae var. anisopliae, and 1.4 x 10 5 e 1.8 x 10 6 conidia/ml of M. anisopliae var. acridum were named dose A and dose B, for each fungus, respectively. These doses corresponded to 3-min and 15-min direct contact of 20 insects with the fungi cultures. Conidia production was evaluated using the insects inoculated with fungi. The bioassays were carried out in triplicate.

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RESUMO Pesquisas sobre patogenicidade necessitam de conhecimentos básicos em biologia e ecologia dos organismos envolvidos no estudo. O presente trabalho descreve uma técnica de manutenção do cupim Nasutitermes coxipoensis em condições de laboratório a fim de realização de testes com fungos entomopatogênicos. Os cupins foram mantidos em caixas plásticas contendo pedaço de ninho (20 g) e substratos alimentares diferentes: madeira em decomposição, madeira seca, colmo de cana-de-açúcar e papel madeira. Utilizou-se a função de sobrevivência S(t) com o objetivo de verificar a probabilidade de vida dos insetos até um tempo t (18 dias), a fim de mantê-los em condições de laboratório. Os resultados indicaram que o substrato que possibilitou maior tempo de sobrevivência foi cana-de-açúcar, seguido de papel madeira picado. Tais informações possibilitarão a realização de testes diversos com cupins, em condições de laboratório.