Thickshell pondsnail

Thickshell pondsnail
Drawing of apertural view of the shell of Stagnicola utahensis.
Conservation status
Scientific classification
Kingdom: Animalia
Phylum: Mollusca
Class: Gastropoda
(unranked): clade Heterobranchia
clade Euthyneura
clade Panpulmonata
clade Hygrophila
Superfamily: Lymnaeoidea
Family: Lymnaeidae
Subfamily: Lymnaeinae
Genus: Stagnicola
Species: S. utahensis
Binomial name
Stagnicola utahensis
(Call, 1884)[2]
Synonyms

Radix ampla var. utahensis Call, 1884
Radix utahensis (Call, 1884)
Galba utahensis (Call, 1884)
Polyrhytis utahensis (Call, 1884)

Stagnicola utahensis, common name the thickshell pondsnail, is a species of air-breathing freshwater snail, an aquatic pulmonate gastropod mollusk in the family Lymnaeidae, the pond snails.

Contents

Shell description

The shell is globose, somewhat umbilicated and irregularly costate. The color of the shell is light horn and nearly pellucid. The spire is rather small and conical. The shell has from 4 to 4 and half convex whorls, that are somewhat flattened above, giving rather a shouldered appearance to the whorls. Whorls are rapidly increasing in size. The last whorl is inflated, with numerous rather marked transverse costae and minutely wrinkled. The suture is somewhat deep, regularly impressed.[3]

The aperture is elongately ovate, effuse, approaching patulous and pearly white within. The outer lip is simple and its margin is connected by a slight calcareous deposit. The columella is somewhat twisted, but straight in front.[3]

The average width of the shell of Stagnicola utahensis is 7.10 mm. The average height of the shell is 13.40 mm. The maximum width of the shell is 8.88 mm. The height of the shell is 16.82 mm. The width of the aperture is 5.90 mm. The height of the aperure is 9.00 mm.[3]

Anatomy

The anatomy of the radula was not published.[3] (cf. [4])

Distribution

This species is endemic to the United States and it is known only from Utah Lake. The type locality is Lake Utah, Lehi, Utah.[3]

The species was "rare" in the lake Utah in 1880s already.[3]

The last living examples are reported from early 1930s.[4]

Ecology

It was associated with abundant specimens of the snails Valvata utahensis and Fluminicola fusca and with bivalve Sphaerium dentatum.[3]

References

This article incorporates public domain text from reference [3]

  1. ^ Mollusc Specialist Group (1996). Stagnicola utahensis. 2006 IUCN Red List of Threatened Species. Downloaded on 7 August 2007.
  2. ^ Call R. E. (1884). Bull. U. S. Geol. Sur. 11: p. 47, plate VI., figures 7-9.
  3. ^ a b c d e f g h Call R. E. (1886). "On certain recent, quarternary, and new fresh-water Mollusca". Proceeding Davenport Academy of Natural Sciences 5: page 5, plate I, figure 7-9.
  4. ^ a b THICKSHELL PONDSNAIL. Utah Division of Wildlife Resources, accessed 21 July 2009.