Somewhat unexpectedly it was found that most circum-Holarctic species occupy the boreonemoral zone (41%), or may even have a polyzonal range (23%).
Species having polyzonal ranges or those that are synantropic have the widest ranges and can occur almost throughout the whole Holarctic.
Appendix 1): Arctic = tundra zone (ar); Boreal = taiga or coniferous forest belt (bo); Hypoarctic = arctic 1 northern taiga + mountain tundra in boreal zone (hy); Nemoral = zone south of boreal: mixed or deciduous forest, steppe, desert (ne); Polyzonal = wide range within above types (po); Montane = mountains in nemoral zone (mo); Cosmopolitan (cos), see also Fig.
However, it was found that most of circum-Holarctic species occur in the boreo-nemoral zone (41% or 43 species), and many even have a polyzonal range (23% or 24 species).
The distribution types used are: arctic (ar), boreal (bo), hypoarctic (hy), nemoral (ne), polyzonal (po), montane (mo) and cosmopolitan (cos), see also Methods.
tripunctata Holm 1978--hy-bo; Trachyzelotes jaxartensis (Kroneberg 1875)--steppe-semidesert; Zelotes puritanus Chamberlin 1922--disjunctive polyzonal range, restricted to warm and xeric habitats from tundra zone to steppes and mountains.
Previous studies have found that (1) each zone contains characteristic and polyzonal
species; (2) species richness declines with increasing latitude, and (3) that more holarctic species breed in northerly than southerly zones (Kistchinskii, 1988; Stishov et al., 1989).