Print Fact Sheet

Beddomeia franklinensis Ponder & Clark, 1993

Diagnostic features

Species in the B. tasmanica group have small shells (length 1.2-2.8 mm) with a depressed spire and open umbilicus. The penis is simple. 

This species differs from other members of this group in its smaller shell with thicker inner lip, small to closed umbilicus and protoconch of about 1.3 whorls with more distinct pitting; radula with heavily indented dorsal edge of central and lateral teeth, sharply pointed median cusps of central and lateral teeth, more cusps on outer side of lateral teeth (7-8 instead of 4-5) and fewer cusps on outer marginal teeth; pallial cavity with weak to absent rectal arch; female genital system with single bend in proximal coiled oviduct, capsule gland about equal in length to albumen gland and with simple ventral channel

Classification

Beddomeia franklinensis Ponder & Clark, 1993

Class Gastropoda

Subclass Caenogastropoda

Order Littorinimorpha

Superfamily Truncatelloidea

Family Tateidae

Genus Beddomeia Petterd, 1889

Original name: Beddomeia franklinensis Ponder & Clark, 1993 in Ponder, W.F., Clark, G.A., Miller, A.C. and Toluzzi, A. (1993). On a major radiation of freshwater snails in Tasmania and eastern Victoria: a preliminary overview of the Beddomeia group (Mollusca: Gastropoda: Hydrobiidae). Invertebrate Taxonomy 7: 501-750. 

Type locality: Franklin River, on riffle crossing at upper side of island-platform, Tasmania.

Biology and ecology

Under large stones and rock slabs in deeper parts of the river. The white egg capsules are laid on the undersides of rocks and are like those of other species of Beddomeia - dome-shaped, with broad attachment base, covered with minute, mainly white sand grains and other fragments and containing a single egg. Development direct..

Distribution

This species occurs in the Franklin River, Tasmania.

Notes

All species of Beddomeia are geographically isolated and have restricted ranges.

Further reading

Ponder, W. F., Clark, G. A., Miller, A. C. & Toluzzi, A. (1993). On a major radiation of freshwater snails in Tasmania and eastern Victoria: a preliminary overview of the Beddomeia group (Mollusca: Gastropoda: Hydrobiidae). Invertebrate Taxonomy 7: 501-750.