A Schistostega pennata (Bryophyta) spore devourer in flagranti—a troglophyle mite Kunstidamaeus lengersdorfi (Acari, Oribatida: Damaeidae)

Abstract

This is the first record of the intentional consumption of moss spores by an arthropod. A moss mite Kunstidamaeus lengersdorfi (Oribatida: Damaeidae) was observed in Moscow Province, Russia, as regularly visiting mature capsules of the moss Schistostega pennata (Schistostegaceae) and eating spores from the opened capsules. The spores of Schistostega are thin-walled, sticky, not dispersed by wind, and exposed at the capsule mouth for easy consumption, being very similar in this respect to the spores of the entomochorous mosses of the Splachnaceae family. Walking through Schistostega population, these mites carry a lot of its spores of their bodies. According to published data, Kunstidamaeus is mostly feeding on saprotrophic fungi and green algae. Behavioral observations as well as the gut content study show that Kunstidamaeus lengersdorfi can also feed on spores of Schistostega pennata. This is the first record of Kunstidamaeus lengersdorfi in Russia. Previously it was known in Central Europe at cave entrances. In a parallel way, Schistostega grows in Central Europe mostly in caves, while it recently explosively spread in boreal, especially spruce-dominated forests in the Central European Russia. The available data indicate that the mite range expansion had followed the expansion of its forage plant.