Data Collection

The practical fieldwork was performed from 06 December 1997 to 13 February 1998 (Afrophlaeoba and Parodontomelus). The data was recorded during a short period of time to avoid seasonal influences. In order to collect data on the microhabitat preferences, the method described by Hochkirch (1995, 2001) was used. All data were obtained between 8:00 and 18:00 at the exact location of undisturbed individuals, which were haphazardly chosen. For each grasshopper the following information was recorded: date, time, study site, species, sex, behaviour, vegetation cover (divided into grasses, forbs, mosses, litter and bare ground, estimated in a circle of 25 cm radius around the individual), vegetation height (highest plant in a circle of 25 cm radius) and the substrate, on which the insect perched (including the categories grasses, forbs, bare ground, leaf litter, grass litter). Temperature and radiation was also recorded, but not included in the analyses as these values depend too much on weather conditions. In total, 300 records were available for the four Afrophlaeoba species and for P. arach-niformis. For comparison, data of sympatric species of the East Usambara Mts. were included, which were recorded from 11 June 1994 to 13 November 1994 (R. usambaricum, P. pygmaeus, I. transiens). The data was obtained similarly to the above mentioned, but vegetation cover was not divided into different categories. In total, 732 records were obtained for R. usambaricum, 637 records for P. pygmaeus and 184 records for I. transiens.

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