Pyramidulidae
Pyramidula rupestris
The genus Pyramidula is the type genus ( and only genus ) of the pyramid snails ( Pyramidulidae ) from the subordination of terrestrial snails ( gastropod ). The few species (currently about twelve species) are inhabitants dry, warm and rocky sites.
Features
The dextral housing are flat - conical with strongly graded, strongly arched whorls ( " pyramid "). They measure about 2.5 to 2 mm in height and about 2.5 to 3 mm in diameter. The housings have about 4.5 whorls, the body whorl is in some populations even somewhat relieved, but usually lowered only slightly or not from the turns. The round mouth is opposite the turns slightly bevelled. The aperture rim is not thickened or folded. There are also no projections ( "teeth" ) in the mouth inside. The surface is reddish brown to dark brown and provided with irregular growth lines. Older animals are faded and almost white. In the male part of the reproductive system, the penis on a sac- like appendage. The Penisretraktormuskel is approximately in the middle of the epiphallus. The stem of the spermathecae is without diverticula. Reproduction is ovoviviparous.
Occurrence and life
The family is spread from Western Europe (Ireland), over central Europe, Asia Minor, Crimea, Caucasus and the Himalayas to Japan. You lack in Scandinavia, in the south of the area of distribution extends over southern Europe to North Africa. The animals live on dry, rocky sites on calcareous rocks. They live hidden in the crevices and columns and are active in wet weather. They feed on lichens growing on the rocks. The animals are ovoviviparous.
System
The pyramid snails ( Pyramidulidae ) family is one of 13 families of the superfamily Pupilloidea. It contains at the moment only one genus, the eponymous genus Pyramidula. Only two species occur in Central Europe.
- Pyramid snails ( Pyramidulidae Kennard & Woodward, 1914) Genus Pyramidula Fitzinger, 1833 Pyramidula cephalonica ( Westerlund, 1898)
- Pyramidula chorismenostoma ( Westerlund & Blanc, 1879)
- Pilsbry & Hirase Pyramidula conica, 1902, Japan
- Pyramidula euomphalus ( Blanford, 1861), India
- Pyramidula halyi ( Jousseaume, 1894), Sri Lanka
- Pyramidula humilis ( Hutton, 1838), India
- Pyramidula jaenensis ( Clessin, 1882)
- Pyramidula kuznetsovi Schileyko & Balashov, 2012
- Pyramidula przevalskii Lindholm, 1922
- Pyramidula pusilla ( Vallot, 1801)
- Pyramidula rupestris ( Draparnaud, 1801)
- Pyramidula umbilicata ( Montagu, 1803)