The Ptiliid Spermatheca

W. Eugene Hall

Structure of the ptiliid female spermatheca (sperm storage organ) is of such unique design that nothing compares to it within other groups of Coleoptera. It has proven to be the most critical taxonomic character when determining species of featherwing beetles. This is especially helpful, as most species of ptiliids within a genus generally appear identical when making identifications based on external morphology. However, spermatheca design is so varied between genera, that it has proven to be a poor character when determining higher groups of taxa.

The spermatheca is generally composed of a sac-like structure of variable form, possessing a spermathecal pump, a structure unique to Ptiliidae. In properly prepared specimens, the spermathecal pump muscles are visible laterally to the pump apparatus.

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Nossidium spermantheca Pteryx spermatheca Acrotrichis spermatheca

The images above illustrate the wide variety of spermatheca designs between various genera of Ptiliidae (Nossidium, Pteryx, Acrotrichis).

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University of Arizona

Page: Tree of Life The Ptiliid Spermatheca Authored by W. Eugene Hall. The TEXT of this page is licensed under the Creative Commons Attribution-NonCommercial-ShareAlike License - Version 3.0. Note that images and other media featured on this page are each governed by their own license, and they may or may not be available for reuse. Click on an image or a media link to access the media data window, which provides the relevant licensing information. For the general terms and conditions of ToL material reuse and redistribution, please see the Tree of Life Copyright Policies.

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