BIODIVERSITY AND MICROHABITAT DISTRIBUTION OF EARTHWORMS AT “EVOLUTION CANYON,” A MEDITERRANEAN MICROSITE, MOUNT CARMEL, ISRAEL

ABSTRACT

Seven species of earthworms were identified at a Lower Nahal Oren microsite, Mt. Carmel, Israel, known as “Evolution Canyon": Bimastos syriacus (Rosa, 1893), Dendrobaena semitica (Rosa, 1893), D. orientalis (¤ernosvitov, 1940), D. veneta (Rosa, 1886), D. samarigera samarigera (Rosa, 1893), Microscolex dubius (Fletcher, 1887; the first record in Israel), and Allolobophora sp. Characteristic compositions of earthworms were found on the south-facing slope (SF), the north-facing slope (NF), and the bottom of the dry watercourse. B. syriacus was abundant in all three habitats together with 3–4 smaller Dendrobaena or Allolobophora species. D. semitica was prevalent on the bottom, while D. orientalis and M. dubius were found only there. D. veneta and D. s. samarigera were more abundant on NF and SF, respectively. Allolobophora sp. was found on both slopes in very low numbers. Earthworm density on ecologically warmer, drier, and more heterogeneous SF was significantly higher in the shade under tree canopies and bushes than in open sunny microhabitats, while on NF no significant differences were found between shady and sunny microhabitats.