Vertigo ultimathule

Vertigo ultimathule is a species of minute, air-breathing land snail, terrestrial pulmonate gastropod molluscs or micromollusks in the family Vertiginidae, the whorl snails.

Vertigo ultimathule
Apertural view of the shell of the holotype of Vertigo ultimathule
Conservation status
Near Threatened  (IUCN 3.1)[1]
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Gastropoda
(unranked):	clade Heterobranchia clade Euthyneura clade Panpulmonata clade Eupulmonata clade Stylommatophora clade Orthurethra
Superfamily:	Pupilloidea
Family:	Vertiginidae
Subfamily:	Vertigininae
Tribe:	Vertiginini
Genus:	Vertigo
Species:	V. ultimathule
Binomial name
Vertigo ultimathule von Proschwitz, 2007[2]

Distribution

Distribution map of Vertigo ultimathule. The type locality in Sweden is marked with a larger dot.

Distribution of Vertigo ultimathule include:

• Finnmark County in the river valleys of the River Tana and its tributary Anarjohka,[3] Norway[1]
• Pältsan, the very northernmost part of Sweden,[1][3]

The type locality is Pältsan-area, in northernmost corner of Swedish Lapland.[3]

Occurrences are to be expected in other parts of Finnmark and adjacent parts of Finland and Sweden.[3] At the present state of knowledge, Vertigo ultimathule must be considered a rare element with a very limited distribution – endemic to northernmost Norway and Sweden.[3]

Description

Aperture.

Vertigo ultimathule is a medium-sized Vertigo, which reaches a height of 2.1–2.2 mm and a diameter of 1.3–1.4 mm, the number of whorls is 4.6–4.7.[3] The shell is almost cylindrical, with marked convex whorls, which are separated by a marked, deep suture. The shape is not distinctly ovoid, as in some other Vertigo-species, and the last whorl does not narrow markedly at the base. In side view from left the outer margin of the last whorl forms a blunt angle close to the umbilicus. The aperture is completely toothless or with only a small, delicate, rather deeply set parietal denticle. The mouth-edge is simple and scarcely thickened. The colour of the shell is light yellow – dark yellow-brown. The surface is glossy, with marked, but irregular, rather coarse striation.[3]

Apical view.

Umbilical view.

Lateral view.

Lateral view.

Ecology

The localities of Vertigo ultimathule are brook valleys or mountain slopes with mountain birch and often Salix shrubs. The pH of the ground litter was measured in two of the localities, the values obtained were 6.75 and 6.0.[3] The Norwegian localities are situated at 180–200 m altitude; the Swedish somewhat higher, at 520–620 m altitude.[3]

References

This article incorporates CC-BY-3.0 text from the reference[3]

1. von Proschwitz T. & Neubert E. (2011). "Vertigo ultimathule". The IUCN Red List of Threatened Species. Version 2014.3. <www.iucnredlist.org>. Downloaded on 03 February 2015.
2. Proschwitz T. von (2007). "Vertigo ultimathule n. sp., a new whorl-snail from northernmost Sweden (Gastropoda: Pulmonata: Vertiginidae)". Heldia 5(3): 73-74, Table 9.
3. von Proschwitz T. (2010). "Three land-snail species new to the Norwegian fauna: Pupilla pratensis (Clessin, 1871), Vertigo ultimathule von Proschwitz, 2007 and Balea sarsii Philippi, 1847 [= B. heydeni von Maltzan, 1881]". Fauna norvegica 30: 13-19. doi:10.5324/fn.v30i0.628

Further reading

• von Proschwitz T. (2008). "Faunistical news from the Göteborg Natural History Museum 2007 – snails, slugs and mussels – with some notes on Vertigo ultimathule von Proschwitz – a landsnail species from northernmost Sweden new to science". Göteborgs Naturhistoriska Museum, Årstryck 2008: 51-72.

External links