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

Sclerodermus abdominalis Westwood, 1839^gSclerodermus brevicornis Kieffer, 1906^gSclerodermus cereicollis Kieffer, 1904^gSclerodermus concinnus Saunders, 1881^gSclerodermus cylindricus Westwood, 1839^gSclerodermus domesticus Latreille, 1809^gSclerodermus ephippius Saunders, 1881^gSclerodermus fasciatus Westwood, 1839^gSclerodermus fonscolombei Westwood, 1881^gSclerodermus formiciformis Westwood, 1839^gSclerodermus fulvicornis Westwood, 1839^gSclerodermus fuscicornis Westwood, 1839^gSclerodermus fuscus ^gSclerodermus gracilis Saunders, 1881^gSclerodermus intermedius Westwood, 1839^gSclerodermus linearis Westwood, 1881^gSclerodermus minutus Westwood, 1839^gSclerodermus nipponicus Yuasa, 1930^gSclerodermus nitidus Westwood, 1839^gSclerodermus pedunculus Westwood, 1839^gSclerodermus piceus Westwood, 1839^gSclerodermus rufus ^gSclerodermus rufescens ^gSclerodermus sidneyanus Westwood, 1874^g
Data sources: i = ITIS, c = Catalogue of Life, g = GBIF, b = Bugguide.net