Columella nymphaepratensis
| Columella nymphaepratensis | ||||||||||||
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| Scientific name | ||||||||||||
| Columella nymphaepratensis | ||||||||||||
| Hlaváč & Pokryszko , 2009 |
Columella nymphaepratensis is a land snail species from the family of diaper snails (Vertinigidae); the family belongs to the subordination of land snails (Stylommatophora). The species is only known from a few localities in Kashmir .
features
The right-hand wound, cylindrical housing is 2.1 to 3.1 mm high and 1.1 to 1.3 mm wide. The height / width index is up to 2.62 (2.6 for the holotype). The adult cases have 6.0 to 7.6 turns (on average 6.8, holotype = 6.8). Specimens with less than six turns are not yet sexually mature. The turns are relatively flat at the periphery, and the seam is correspondingly shallow. The apex is rounded. Most specimens do not have the last turn, and in a few specimens only slightly expanded. In the side view, the mouth edge is almost straight, so it does not rise or fall. The mouth is egg-shaped, in adult animals the width is always greater than the height. The skin is relatively thin, light brown in color and semi-translucent. The surface shows not very clear, very fine and somewhat irregular spiral stripes. The comparatively large navel is open and rounded in outline.
In the hermaphroditic genitalia, the male ducts are often reduced (aphallic, four out of five specimens examined). The gonads are two-sided with short exits. The pigment spots above the fans are separate and not fused together. The top spot is slightly smaller than the bottom spot. The spermatic duct is moderately long and not very tortuous. It opens apically into the short epiphallus, which merges into the penis after a slight constriction. The penis is comparatively long and thick. The penis retractor inserts approximately in the middle of the total length of the penis.
Similar species
Columella nymphaepratensis resembles Columella columella (Martens) and Columella edentula (Draparnaud) due to its cylindrical shape . It differs from the first type in that the turns flattened at the periphery and the flat seam, as well as the less bloated last turn. The skin is shinier and shows more through, and the striations are weaker. In addition, the mouth is almost straight when viewed from the side. Also Columella edentalus (Draparnaud) and Columella aspera Waldén have more arched turns and deeper seams. In addition, the housing of the latter two types is more ovoid-conical. Columella asperas is more ribbed. Columella intermedia has more arched turns and deeper seams, a more translucent shell, ribs or regular growth strips and a somewhat heavily inflated last turn. Columella acicularis Almukhambetova has an egg-shaped housing with also more strongly arched coils and deeper seam. The mouth is almost square.
Geographical distribution and habitat
The species has only been found in a few locations in the Diamir and Skardu districts of the Federally Administered Northern Areas in the Pakistani part of Kashmir.
The animals occur there between 2900 and 3900 meters above sea level on a subsoil consisting of granodiorite or gneiss . They live in the leaf litter and under stones in light birch forests or bushes, also a pine forest and on damp meadows.
Taxonomy
The species was first described in 2009 by Jaroslav Hlaváč and Beata Pokryszko . The species name is derived from the Latin "nymphae", spirits that were believed to live in the sea, rivers and springs, and the Latin "pratensis", found in meadows. Type locality are the Fairy Meadows, Raikhot Gah, north side of Nanga Parbat , 6.5 km south of the village of Tato, 35 ° 20'N, 74 ° 36'E in the Diamir district, FANA, Kashmir, Pakistan. The type locality is in the western part of the Fairy Meadows at 3300 m above sea level.
literature
- Beata M. Pokryszko, Kurt Auffenberg, Jaroslav Č. Hlaváč, Fred Naggs: Pupilloidea of Pakistan (Gastropoda: Pulmonata): Truncatellininae, Vertigininae, Gastrocoptinae, Pupillinae (In Part). Annales Zoologici, 59 (4): 423-458, 2009 doi : 10.3161 / 000345409X484847