Les Simulies d'Algérie (Diptera : Simuliidae). I. Premières données biogéographiques et écologiques sur les espèces de l'Ouest-algérien

Abstract

Les Simulies d'Algérie (Diptera : Simuliidae). I. Premières données biogéographiques et écologiques sur les espèces de T Ouest-algérienJ. Gagneur! M. Clergue-Gazeau^ Mois clés : Stmuliidae, Algérie, faunistique, zoogéographie.48 stations ont été prospectées sur les oueds du Nord-Ouest de l'Algérie, entre 1145 m d'altitude et le niveau de la mer : 20 espèces de Simulies ont été récoltées. Un genre, un sous-genre et 7 espèces sont cités pour la première fois en Algérie ; une espèce est nouvelle pour l'Afrique du Nord.Mis à part Simulium (Witheimia) pseudeqtdnum, d'origine orientale, la faune appartient à la zone paléarctique (au Sud de la sous-région méditerranéenne) et s'adapte à de nouvelles caractéristiques des cours d'eau (température, salinité...) ; ainsi, les espèces de plaine de la bordure septentrionale méditerranéenne remontent dans un crénal de moyenne altitude et se retrouvent ici avec les espèces de sources.Les éléments oi-ophiles sont très peu représentés. Simuliidae of Algeria (Diptera : TVematocera). I. Biogeographical and ecological data on the species of West Algeria.Keywords ; SimuHdae. Algeria, faunistic, zoogeography.48 sites have been examined in the « oueds » (-wadi) of North-West Algeria between sea-level and a height of 1145 m. 20 species of Simuliidae have been collected. One genus, one sub-genus and seven species are recorded for the first time for Algeria ; one species is a new record for North Africa.Apart from Simulium fWilhelmia) pseudequinum which is of eastern origin, the fauna belongs to the palaearctic zone (to the south of the mediterranean subregion), and is adapted to the new characteristics of the watercourses (temperature, salinity.,.). Therefore, the species of the plain next to the mediterranean in the north have ascended to a mean altitude and are found together with species occurring at the source.Orophilic (moutain-loving) elements are very poorly represented.

Habitat Characterization of Black Flies (Diptera: Simuliidae) in the Tafna Catchment of Western Algeria

“…Of the 10 species in our samples, seven previously have been reported in Tafna catchment by Gagneur and Clergue-Gazeau [6]: S. velutinum, S. ruficorne, S. bezzii, S. intermedium, S. ornatum (complex), S. pseudequinum, and S. sergenti. They have also found in wadis of the Djurdjura Mountains in northern Algeria [8] and in the Seybouse River Basin in northeastern Algeria [10].…”

“…Larvae and pupae of these species are abundant in shallow waters, rich in organic material and filamentous algae [8]. The ability of these species to inhabit a large range of ecological factors was reported by several authors [6] [7] [21] [31] [36]. Larvae of S. velutinum are found at moderate velocities, but also can be found in slow currents [24].…”

“…Measurements of the instantaneous stream velocity, using the weighted float technique [6], allowed five classes of currents velocity to be identified (VF: very fast, F: fast, M: medium, S: slow, VS: very slow). The substrate nature ( Table 1) was determined from the erosion facies (coarse grains: rocks, stones and pebbles) or from sedimentation (fine grains: sand, silt, and mud).…”

“…Apart from the first inventory [1], the early studies were devoted to the description of species but rarely to their ecology [2]- [5]. During the last three decades, the only available ecological data are scarce [6]- [8] and more recently those of Chaoui Boudghane-Bendiouis [9] and Cherairia [10].…”

“…The present study, performed 25 years after the work by Gagneur and Clergue-Gazeau [6] on Simuliidae in the Tafna catchment, aims to identify the faunal composition, to provide update simuliid geographic observations and understand the organization of the community by analysis of the micro-distribution of species within differentiated microhabitats according to the current-substrate complex. The concept of a relationship between the specific characteristics of microhabitats and the micro-distribution of macroinvertebrates has been highlighted by numerous authors [11]- [14].…”