Often, female insects store sperm in a tube-like structure known as the spermatheca. In most staphylinids, spermathecae are sclerotized and in several groups the structures are unique at the species level. Interspecific differences are particularly prevalent in aleocharines and spermathecal morphology can be extremely elaborate.
This is a spermatheca which starts (it ends in the large bulb) out as a tight coil, only to back-track as large loops that circumvent the original tight coil – strange. This morpho-type has evolved independently in several aleocharine lineages. In some cases, the length of the male copulatory structures correlate to female spermathecal length, possibly due to some sort of “lock and key” relationship, but this is not the case in this species. Another possible explanation for this morphology, is that the sperm themselves have extremely long flagella, and the coils are merely to keep the structure compact. This would be an interesting avenue of inquiry.