Factors influencing the distribution, abundance and diversity of geophilomorph and lithobiomorph centipedes

Geophilomorph and lithobiomorph centipedes were collected from 45 sampling sites spread across an area of c. 4000 km(2) in north-east England. Data on physical variables were also collected at these sites, including the soil variables of pH, moisture content, organic content and compaction, which have been generally neglected in previous studies of centipede ecology. Fourteen species were found overall, evenly split between the two orders. Of these 14, three were 'rare' ( less than or equal to three individuals), six were 'intermediate' (10-50 individuals), and five were 'common' (100+ individuals). Analysis of presence/absence data on the intermediate species showed that the geophilomorphs were markedly synanthropic whereas the lithobiomorphs were not. More extensive analysis of the data on the five common species revealed a number of patterns. including: ( 1) a negative association between the two largest lithobiomorphs (2) the importance of many predictor variables, including the soil variables, but with very different patterns for different species. Overall, synanthropic sites had the highest centipede diversities, but this effect was almost entirely caused by the synanthropic tendencies of the 'intermediate' geophilomorphs.