Sclerodermus


Sclerodermus is a genus of chrysidoid wasps in the family Bethylidae. There are at least 20 described species in Sclerodermus.

Reproduction and sex ratios

Species of Sclerodermus exhibit quasi-social behavior: multiple females cooperate to paralyze a host and care for a shared brood. Despite this cooperation, they consistently produce highly female-biased sex ratios often with less than 10% males, even when many mothers are present.
According to classical sex ratio theory, more mothers should lead to a more balanced ratio of sons and daughters, since males would no longer be competing only with their brothers to mate. The extreme female bias in Sclerodermus contradicts this expectation. Recent models suggest that dominant females may influence sex ratios by killing the sons of subordinates or preventing their production, a behavior known as infanticide. These social dynamics help explain the unusual patterns observed in this genus.

Species

Data sources: i = ITIS, c = Catalogue of Life, g = GBIF, b = Bugguide.net