Fluvidona petterdi (E. A. Smith, 1882)

Diagnostic features

Shell pupiform, with strongly convex whorls; operculum with 2.3 moderately long pegs. Fluvidona anodonta is very similar to F. petterdi in shell features but tends to be a little smaller and the spire is a little longer. In opercular characters if differs in having shorter opercular pegs. The two taxa also differ in several anatomical characters but both have a simple penis.

This is one of several species of Fluvidona found in northern New South Wales and southern Queensland. They are all very similar, being separated on small differences in size and shape of the shells and in anatomical details. They have elongate-conic shells with adults having a slightly thickened aperture and the operculum bears one or more pegs.

Classification

Fluvidona petterdi (E. A. Smith, 1882)

Class Gastropoda

Infraclass Caenogastropoda

Order Littorinida

Suborder Rissoidina

Superfamily Truncatelloidea

Family Tateidae

Genus Fluvidona Iredale, 1937

Original name: Hydrobia petterdi E. A. Smith, 1882.  In Smith, E. A. (1882). On the freshwater shells of Australia. Journal of the Linnean Society, Zoology 16(92): 255-316, plates 5-7.

Type locality: Small stream flowing into the Richmond River, New South Wales.

Synonym: Bithynia richmondiana Petterd, 1884.

Biology and ecology

Under stones in small stream, uncommon. Assumed to feed by scraping bacteria and possibly microalgae. Presumed solitary capsules with single egg.

Distribution

Known only from one small stream in Lismore, New South Wales.

Notes

Species of Fluvidona are geographically isolated and appear to have very restricted ranges. This species is known from only one stream in Lismore. The types are from a "small stream flowing into the Richmond River".

Further reading

Miller, A. C., Ponder, W. F. & Clark, S. A. (1999). Freshwater snails of the genera Fluvidona and Austropyrgus (Gastropoda, Hydrobiidae) from northern New South Wales and southern Queensland, Australia. Invertebrate Taxonomy 13: 461-493.

Iredale, T. (1944a). Guide to the freshwater shells of New South Wales. Part 2. Australian Naturalist (Sydney) 11: 113–127.