The Earthworm Fauna of Chréa National Park (Algeria)

The present work studied the ecobiological distribution of earthworms of Chrea National Park of Algeria. Three stations were investigated: Foret Noire, Hakou ferraoune, and Sidi Rabeh. Their separation is based on vegetation and soil characteristics. The determination of species is based on the morphology of the samples preserved in the 4% formalin. The morphological criteria considered are dimension, tegument, and segmentation regions of the body, silks, external sexual characters, pores, general anatomical plan, nephridia, digestive tract, and reproductive organs. 1628 earthworms were sampled and represented by three families: Acanthodrilidae, Megascolecidae, and Lumbricidae. Five genera represented by eight species were discovered. The individuals were identified as the following species: Nicodrilus caliginosa, Allolobophora rosea, Allolobophora cholorotica, Amynthas sp., Microscolex phosphoreus, Octodrilus complanatus, Octodrilus maghrebinus triginta, Dendrobaena pantaleonis. Dendrobaena pantaleonis is a new record for Algeria. High densities of earthworms have been recorded under the cork oak, where the soil is rich in organic matter, followed by cedar soils with less organic matter. Both species Nicodrilus caliginosus and Octodrilus complanatus are absent in a poor soil in organic matter and under Quercus canariensis.