Male dimorphism in Oedothorax gibbosus (Araneae, Linyphiidae): A morphometric analysis

The linyphiid spiders Oedothorax gibbosus (Blackwall 1841) and Oedothorax t uberosus (Blackwall 1841) were formerly described as separate species due t o marked differences in prosomal structures of the males. During the last d ecade if was demonstrated that they are two forms of a single species. Howe ver, it remained to be shown whether the former species represent two disti nct morphs or extremes of a continuum of variation. A morphometric examinat ion of 246 alcohol-preserved specimens revealed that individual spiders can clearly be assigned to one of two forms. No intermediates were found, demo nstrating that there are two distinct morphs.