Cold Resistance and the Distribution of Genetic Lineages of the Earthworm Eisenia nordenskioldi (Oligochaeta, Lumbricidae)

Resumo

It has been noted that the taxonomic status of genetic lineages isolated within the widespread earthworm species Eisenia nordenskioldi is not clear; differences in their cold resistance indicate in favor of advanced intraspecific differentiation. It was found that there are both moderately resistant (tolerating a cooling of –10…–12°C) and surviving at significantly lower temperatures (–28…–34°C) among the four E. n. nordenskioldi subspecies lines studied and the two E. n. pallida subspecies lines. It was established that the state of ranges of some genetic lines can be explained by worm resistance to negative temperatures, while in some other cases the ranges of genetic lines does not coincide with the expected spatial limits.