This small bivalve is superficially similar to some sphaeriids, but differs in its anatomy and hinge features. It is most readily distinguished by the ligament which is housed in a pit below the posterior part of the hinge. In sphaeriids, the ligament is in a pit on the outer edge of the posterior hinge plate.
Arthritica korniushini Ponder, 2023
Class Bivalvia
Infraclass Heteroconchia
Cohort Heterodonta
Megaorder Neoheterodontei
Order Venerida
Superfamily Galeommatoidea
Family Lasaeidae
Genus Arthritica Finlay, 1926 (type species: Kellia bifurca Webster, 1908; New Zealand, marine)
Original name: Arthritica korniushini Ponder, 2023. In Ponder, W. F. (2023). The first galeommatoidean from inland waters: a new species of Arthritica (Bivalvia, Lasaeidae) from artesian springs in South Australia, with comments on other Australian members of the genus. Molluscan Research, 1-12. DOI: 10.1080/13235818.2022.2151070
Type locality: Billa Kalina Springs, spring at Old Billa Kalina ruin, Lake Eyre Supergroup, South Australia.
Ponder (2023) provided a review of the Australian species of Arthritica, all of which are marine or estuarine except for the present species. One of the estuarine species, A. semen, is found in estuaries and coastal lagoons around temperate Australia can be found in low salinities. It is distinguished from A. korniushini in having a more triangular, more inflated shell with purple streaks below the umbos.
This species lives in swampy springs, amongst vegetation and sediment. It is the only known freshwater galeommatoidean. The fertilized eggs are brooded in the gills and released as crawl-away juveniles.
In a few freshwater springs in the Lake Eyre basin spring complex, South Australia.
This species is only known from only three spring groups and is potentially threatened.
Beesley, P. L., Ross, G. J. B. & Wells, A., Eds. (1998). Mollusca: The Southern Synthesis. Parts A & B. Melbourne, CSIRO Publishing.
Lewis, M., White, D. & Gotch, T. (2013). Spatial Survey and Remote Sensing of Artesian Springs of the Western Great Artesian Basin, Allocating Water and Maintaining Springs in the Great Artesian Basin National Water Commission, Canberra ACT.
Ponder, W. F. (1965). The biology of the genus Arthritica. Transactions of the Royal Society of New Zealand: Zoology 6: 75-86.
Ponder, W. F. (2023). The first galeommatoidean from inland waters: a new species of Arthritica (Bivalvia, Lasaeidae) from artesian springs in South Australia, with comments on other Australian members of the genus. Molluscan Research, 1-12. DOI: 10.1080/13235818.2022.2151070
Ponder, W. F. & Walker, K. F. (2003). From mound springs to mighty rivers: The conservation status of freshwater molluscs in Australia. Aquatic Ecosystem Health & Management 6: 19-28.
Wells, F. E. & Threlfall, T. J. (1982a). Salinity and temperature tolerance of Hydrococcus brazieri (T. Woods, 1876) and Arthritica semen (Menke, 1843) from the Peel-Harvey estuarine system, Western Australia. Journal of the Malacological Society of Australia 5: 151-156.
Wells, F. E. & Threlfall, T. J. (1982b). Reproductive strategies of Hydrococcus brazieri (Tenison Woods, 1876) and Arthritica semen (Menke, 1843) in Peel Inlet, Western Australia. Journal of the Malacological Society of Australia 5: 157-166.
