| Abstract: | In three ecological studies in the southern parts of Nevada, Idaho, and Utah, spiders of 138 species, scorpions of 10, solpugids of 29, and phalangids of 2 species were obtained by pitfall capture. Significant differences in species occurrence were noted between the three geographic and ecologically distinct areas. Within each geographic area, arachnids differed in species occurrence and abundance in different plant communities. Only three species of spiders and four species of scorpions were common to all three geographic areas. |
