Biosystématique et écologie des orthoptères (Insecta, Orthoptera) dans l’Est algérien.

Abstract

A study of the orthopterans in the Eastern Algerian region was conducted with two main objectives : The first one is a survey of the fauna in 16 localities located in seven regions (Constantine, Batna, Mila, Khenchela, Oum El Bouaghi, Jijel and Skikda) and three bioclimatic stages (semi-arid, subhumid and humid) by an adequate methodology. The total orthopteran fauna is composed of 51 species belonging to both suborders of orthoptera, seven (7) families and 17 subfamilies. Most of the species inventoried belong to the suborder Caelifera (43 species). While the suborder Ensifera is represented by only eight (8) species. The second main objective is to study the orthopteran bioecology, several aspects were discussed. The specific richness is clearly higher in the locality of Fesdis. The family Acrididae is dominant regarding the taxonomic richness, being present in all the study localities. A comparative study using different methods between the localities was carried out. It is emphasized that the species Sciobia algirica (Gogorza, 1881), belonging to the suborder Ensifera, Gryllidae family and Gryllinae subfamily, has never been reported in Eastern Algeria. The family Tetrigidae is only represented by one species ; Paratettix meridionalis (Rambur, 1838), whose bio-ecological study was carried out. Surveys and monitoring of this species show that it has two generations annually. Regarding the diet study of this species, the results of the feces analysis of males and females reveal that it consumes plants belonging to two main families : Asteraceae and Poaceae. The bioecological study of the species Praephippigera pachygaster (Lucas, 1849) belonging to the family Tettigoniidae indicates that this species is polyphagous and prefers plants belonging to the family Asteraceae. It occurs with significant pullulation at Fesdis and El Hamma stations during the study period. The bioclimagrams carried out for the orthopterans of Eastern Algeria show that the largest number of species belongs to the semi-arid bioclimatic stage. The availability of orthopterans is influenced by high temperatures, rainfall and altitude. According to the literature reviewed, the main focus of research on orthopterans has been on caelifera, a few publications have been published on ensifera, thus our work coming to enrich the fauna of Eastern Algeria.