Volume 23

Volume 23 Part 2

Pages
pp. 167 -
170

В лабораторных условиях определен знак фототаксиса брюхоногого легочного моллюска Radix peregra (Müller, 1774). R. peregra показывает положительный фототаксис, который согласуется с его дневным типом активности и высоким уровнем освещенности мест обитания. Положительная реакция на свет обеспечивает моллюску нахождение мест обитания с благоприятными для жизнедеятельности световыми условиями и реализацию функции дыхания.

Знак фототаксиса брюхоногого легочного моллюска Radix peregra (Müller, 1774) (Basommatophora, Lymnaeidae)
Шепелева И.П.;
Pages
pp. 171 -
175

The visual acuity of a gastropod pulmonate mollusk Radix peregra (Müller, 1774) was estimated on the basis of phototaxis in the laboratory conditions. White cards with black vertical stripes of different angular width were used as visual stimuli. A value of the resolving angular distance of photoreceptors was 1-2°, and the calculated on its basis visual acuity -33-16.5 rad-1. The mollusc has a diurnal type of activity and lives at well-illuminated surface patches of ponds on aquatic caulescent plants that it feeds on. The results of behavioral investigation presented in this work and morpho-optical study of the eye carried out earlier allow to consider that R. peregra can identify caulescent plants, suitable for its inhabitation, feeding and travelling to the water surface.

Острота зрения брюхоногого легочного моллюска Radix peregra (Müller, 1774) (Basommatophora, Lymnaeidae)
Шепелева И.П.;
Pages
pp. 177 -
180

The spectral sensitivity of the eye of a gastropod pulmonate mollusk Radix peregra (Müller,1774) was investigated on the basis of phototaxis in the laboratory conditions. The monochromatic light of tendifferent wavelengths in diapason 400-600 nm servedas a test stimulus. According to the results obtained R. peregra has monochromatic visual system with a possible visual pigment rhodopsin, that may be based on the retinal A and absorption maximum of which falls on a blue-green range of the spectrum about 490 nm.

Спектральная чувствительность глаза брюхоногого легочного моллюска Radix peregra (Müller, 1774) (Basommatophora, Lymnaeidae)
Шепелева И.П.;
Pages
pp. 181 -
185

Rare European species Pupilla pratensis is registered in the same calcareous fen in the Crimean Mountains, where Vertigo moulinsiana, another rare European species, was found earlier. Both species are known in Ukraine only from this one small site (less than 0.01 km2), which is disturbed and not protected, therefore both species are clearly “Critically Endangered” here. In the materials of Pupilla muscorum from Ukraine there are some unusual large specimens with shell width 1.9-2.0 mm were revealed, therefore these two species can’t be distinguished only by this characteristic, how it was partly considered before.

Первая находка Pupilla pratensis для Украины в Крымских горах с замечаниями о его природоохранном статусе и отличиях от Pupilla muscorum (Stylommatophora, Pupillidae)
Балашёв И. ;