Phrantela Iredale, 1943

Diagnostic features

Shell pupiform to conic to trochiform, small to medium size for family (between about 1.7 and 7.0 mm in maximum dimension). Periostracum thin to well developed, colourless to dark brown. Teleoconch sculpture usually of faint, prosocline growth lines, weak spiral threads sometimes present; periphery of last whorl usually evenly rounded, sometimes subangled, rarely sharply angled. Aperture ovate, inner lip thin and narrow, columellar swelling typically absent (weakly developed in one taxon). Outer lip thin, slightly opisthocline to prosocline. Umbilicus wide to small, or closed and represented by chink. Operculum oval, thin, transparent pale yellow, simple, with eccentric nucleus. Bursa copulatrix in the female genital system reaches to the posterior pallial wall [or (rarely) almost reaches it or extends into the pallial roof] and has the duct emerging from the ventro-posterior comer. This is one of the main anatomical features that distinguishes this taxon from Beddomeia. The pallial genital ducts in both males and females are thinner in section than in Beddomeia and the female genital opening is typically slit-like, rather than a short, pore-like opening. Generally a posterior pallial tentacle is present.

Classification

Phrantela Iredale, 1943

Class Gastropoda

Infraclass Caenogastropoda

Order Littorinida

Suborder Rissoidina

Superfamily Truncatelloidea

Family Beddomeiidae

Genus Phrantela Iredale, 1943

Type species: Potamopyrgus (?) marginata Petterd, 1889 by original designation.

Original reference: Iredale, T. (1943). A basic list of the fresh water Mollusca of Australia. The Australian Zoologist 10: 188–230.

Type locality: A small trickling stream near Heazlewood River, Tasmania

Biology and ecology

In rivers, streams and seeps, and under small waterfalls. Found on weed along stream edges, on roots and wood, under lichens, sedges and leaves, in moss, under stones or large boulders on sand/gravel base, or in black sticky mud. Egg capsules known from only one unnamed species; small, with single embryo, and covered in coarse sand grains. Development direct.

Distribution

Western and southern Tasmania.

Notes

Wilke et al. (2013) revealed that this genus, like Phrantela and Victodrobia,  are not closely related to Tateidae. Recently Ponder et. al. (2023) recognised these three genera as a separate family, Beddomeiidae.

Further reading

 

Beesley, P. L., Ross, G. J. B. & Wells, A., Eds. (1998). Mollusca: The Southern Synthesis. Parts A & B. Melbourne, CSIRO Publishing.

Ponder, W. (2019). Tateidae Thiele, 1925. Pp. 134-138 in C. Lydeard & Cummings, K. S. Freshwater Mollusks of the World: a Distribution Atlas. Baltimore, John Hopkins University Press.

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. 

Ponder, W. F., Nimbs, M. J. & Shea, M. E. (2023). Hyporheic Tateidae (Gastropoda: Truncatelloidea) from the Flinders Ranges, South Australia and Judbarra (Gregory) National Park, western Northern Territory, Australia, with some taxonomic notes on the family. Molluscan Research 44: 63-83.

Smith, B. J. (1992). Non-marine Mollusca. Pp. i-xii, 1-408 in W. W. K. Houston. Zoological Catalogue of Australia, 8. Canberra, Australian Government Publishing Service.

Smith, B. J. & Kershaw, R. C. (1979). Field guide to the non-marine Molluscs of South-eastern Australia. Canberra, A.N.U. Press.

Smith, B. J. & Kershaw, R. C. (1981). Tasmanian Land and Freshwater Molluscs. Hobart, University of Tasmania.

Wilke, T., Haase, M., Hershler, R., Liu, H.-P., Misof, B. & Ponder, W. (2013). Pushing short DNA fragments to the limit: Phylogenetic relationships of 'hydrobioid' gastropods (Caenogastropoda: Rissooidea). Molecular Phylogenetics and Evolution 66: 715-736.