Land snail communities at Lake Hancza (NE. Poland)

The snail fauna of human-transformed forests (originally ranging from oak-hornbeam to alder swamps) at Lake Hañcza and two nearby lakes in NE. Poland includes 29 species, with 14–18 species per site. There are also four slug species. The ten sampling sites vary rather much in their species composition, the mean Nei index being 0.71 and IMAX 1.57; the heterogeneity does not seem to result from sampling error. In most sites 1–3 species contribute over 50% of total abundance. Most species recorded are common, euryoecious and widely distributed; restricted forest snails, timber-dwellers and vegetation climbers are nearly absent

Forest snail faunas in the Kaszuby Uplands (Pomerania): a rich northern refuge

Forest snail faunas were sampled in three river gorges in the Kaszuby Uplands, Pomorze. 43 species were found, including 10 species of Clausiliidae. Taken with earlier records, these gorges hold 48 species. These faunas are markedly richer than most of those recorded in north and west Poland, especially for clausiliids, where up to eight species could be found in the same sample site. The fauna overall is very similar to that of the ancient Bia³owie¿a Forest much further east. The results suggest that many lowland forests in Poland have impoverished faunas, probably due to human activities, but there are a few refugia in which nearly all of the original forest fauna has survived. These give a better picture of natural patterns of distribution and change across the North European Plain

Correlated phenotypic responses to habitat difference in Cepaea nemoralis (L.)

Using data from the Evolution Megalab Project paired samples of Cepaea nemoralis (L.) coming respectively from woodland and open habitats have been examined for joint response to habitat difference at different polymorphic loci. Throughout the range of the species there is a tendency for open habitat samples to have different frequencies at shell colour and pattern loci from those in neighbouring woods. In Britain, the chance that the frequency of yellow is higher in open than in wooded habitats is about 67 per cent. There is a 41 per cent chance that they will have both higher frequency of yellow and a lower frequency of unbanded at the linked banding locus. Responses of unbanded and the unlinked mid-banded locus are to a large extent independent, however. The chance that open habitats have higher yellow and a lower value for the sum of unbanded and mid-banded (effectively unbanded) is 42 per cent, while the chance that the open habitat sample is more yellow, less unbanded and less mid-banded is no more than 19 per cent. The colour, but not the banding difference was also found in the data for continental Europe. The effect of habitat acts within a polymorphic system. For Britain closely spaced sample pairs have an average frequency difference (Euclidean distance) between habitats at the three loci of about 0.26. As a result of other factors affecting the polymorphism this difference increases to 0.43 for pairs 1 km apart and 0.59 at 10 km apart. These results extend the original findings of CAIN & SHEPPARD (1954) and others but show clearly that the habitat is only part of the explanation for polymorphism in Cepaea

Cochlodina costata (C. Pfeiffer, 1828) (Gastropoda: pulmonata: Clausiliidae) in Poland

An endangered species, Cochlodina costata (C. Pfeiffer), believed to be extinct in Poland, was found on Mt. Miłek (Kaczawskie Mts, SW. Poland)

Cepaea vindobonensis (Férussac, 1821) in the Pieniny Mts

Cepaea vindobonensis (Fér.), previously thought not to occur in the Polish Carpathians, was found in the valley of Biała Woda (Pieniny Mts.: Małe Pieniny)