Species of the B. hullii group are found in the northern half of Tasmania. Their shells are small (1.7-3.7 mm in length; most less than 3.5 mm), simple, ovate-conic to broadly conic, with a thin inner lip and no columellar bulge. The periphery of the last whorl of the shell is rounded, subangled or angled and the penis simple.
This species closely resembles B. fallax in shell characters, but differs in having the bursal duct and oviduct join in front of the posterior pallial wall.
Beddomeia averni Ponder & Clark, 1993
Class Gastropoda
Infraclass Caenogastropoda
Order Littorinida
Suborder Rissoidina
Superfamily Truncatelloidea
Family Beddomeiidae
Original name: Beddomeia averni Ponder & Clark, 1993. In 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.
Type locality: Small stream, 3 km east of Preston, West Gawler, Tasmania.
In small stream, mainly living in tree fern roots, mosses and liverworts. Egg capsules assumed to be like those of other Beddomeia species (dome-shaped, with broad attachment base, covered with minute, mainly white sand grains and other fragments; contain a single egg). Development is direct.
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Only known from type locality near Preston, West Gawler, Tasmania.
All species of Beddomeia are geographically isolated and have restricted ranges.
Occurs sympatrically with two species of Austropyrgus.
This species is on the Tasmanian Threatened Species Protection Act 1995 as Endangered.
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.
