Empty land snail shells collected under the assumption that they are devoid of life forms—other than protists and bacteria, which are unavoidably expendable—upon returning home occasionally bring forth previously hidden occupants, sometimes with tragic results.
This morning, while examining a bag of clausiliid shells that I had collected in Istanbul in May 2007, I noticed a small, about 5 mm long, object covered with stiff hairs. It turned out to be another hapless snail shell dweller that had died in the shell bag while trying to find a way out.
The hairs and the pair of cerci identify it as a larva or a larviform female of the beetle family Drilidae. Here is a closer look at it.
The larvae of drilids are quite common predators of snails in Europe and elsewhere. After a larva consumes a snail, it pupates within the empty shell of its victim, a process that may take several weeks. That's why they appear in containers of otherwise empty shells sometimes many days after the collection.
This post had another example of a drilid from a bag of shells. A recent paper about the drilids of Turkey is Kundrata R., Bocak L. 2007. A revision of Euanoma and Pseudeuanoma (Coleoptera: Drilidae). Annales Zoologici, 57: 427-441 (abstract). This post was about isopods that came out of snail shells.