Two slug species (Krynickillus melanocephalus Kaleniczenko, 1851 and Tandonia kusceri (H. Wagner, 1931)) are reported from Hungary for the first time. Identification was supported by anatomical examination in both, and molecular data in the latter species. A citizen science survey applying a Realtime Social Networking Service (RSNS) method using Facebook posts revealed that both species are already widespread in Hungary, i.e. Krynickillus melanocephalus is reported from 14 and Tandonia kusceri from 25 sites. So far, we received no reports on any damage caused by these two slug species. Nevertheless, we treat them as potential horticultural pests requiring further attention.

No abstract

Apertural barriers of land snails are thought to increase their shell’s effectiveness against dehydration and predation. The most complex apertural barrier among stylommatophoran snails is the clausiliar apparatus (CA) of Clausiliidae. Alopia is a unique genus in having a remarkably high proportion of taxa with a naturally reduced CA, representing at least five independent reduction events. We tested the prevailing hypothesis that the primary role of the CA within the door snail family is to help retain body moisture. In a laboratory experiment, we compared the water loss of two Alopia taxa with naturally reduced and two Alopia taxa with complete CAs. There was a detectable difference in the rate of water loss, but no relationship with the presence/absence of the CA could be shown. In another laboratory experiment, this time in Alinda biplicata, we did not detect significantly higher water loss in specimens from which the clausiliar plate was artificially removed compared to those left intact. These results suggest that the CA has no significant role in water retention but its actual function remains speculative. A possible explanation, which requires further work, could be that the CA provides protection against specific predators intruding through the aperture.