Taiwanassiminea affinis commonly occurs sympatrically with Cryptassiminea spp. in New South Wales, also banded species, but T. affinis is distinguishable from the latter in having a taller spire, strong umbilical ridge and a subsutural spiral cord.
Taiwanassiminea affinis (Böttger, 1887)
Class Gastropoda
Infraclass Caenogastropoda
Order Littorinida
Suborder Rissoidina
Superfamily Truncatelloidea
Family Assimineidae
Subfamily: Assimineinae
Genus Taiwanassiminea Kuroda & Habe, 1950
Original name: Assiminea affinis Böttger, 1887. In Böttger, O. (1887) Aufzählung der zur Gattung Assiminea Fleming gehörigen Arten. Jahrbücher der Deutschen Malakozoologischen Gesellschaft 14, 147–234, pl. 6.
Type locality: Rockhampton, Queensland.
Synonym: Assiminea queenslandica ‘Pilsbry’ Thiele, 1927 (nom. nud.).
Lives in low salinity conditions in the upper tidal reaches of rivers and large streams. It lives under dead leaves, bark on dead wood and stones or around the bases of plants, including grasses, on muddy banks. It occurs in the upper half of the intertidal zone to the high tidal line or slightly above and can be abundant.
Taiwanassiminea affinis is found in the upper tidal reaches of the larger rivers from northern Queensland to the Shoalhaven River in the southern half of New South Wales.
Willan and Kessner (2021) record an apparently undescribed species that is somewhat similar to T. affinis known from two freshwater creeks flowing into the Daly River, Northern Territory. This is figured by them (their figure 22).
Böttger, O. (1887). Aufzählung der zur Gattung Assiminea Fleming gehörigen Arten. Jahrbücher der Deutschen Malakozoologischen Gesellschaft 14: 147-234.
Cotton, B. C. (1942). Australian Gastropoda of the families Hydrobiidae, Assimineidae and Acmeidae. Transactions of the Royal Society of South Australia 66: 124–131.
Fukuda, H. & Ponder, W. F. (2003). Australian freshwater assimineids, with a synopsis of the Recent genus-group taxa of the Assimineidae (Mollusca: Caenogastropoda: Rissooidea). Journal of Natural History 37: 1977-2032.
Fukuda, H. & Ponder, W. F. (2005). A revision of the Australian taxa previously attributed to Assiminea buccinoides (Quoy and Gaimard) and Assiminea tasmanica (Tenison Woods) (Mollusca: Gastropoda: Caenogastropoda: Assimineidae). Invertebrate Systematics 19: 325-360.
Fukuda, H., Ponder, W. F. & Hallan, A. (2015). Anatomy, relationships and distribution of Taiwanassiminea affinis (Böttger)(Caenogastropoda: Assimineidae), with a reassessment of Cyclotropis Tapparone-Canefri. Molluscan Research 35: 24-36.
Hallan, A. & Fukuda, H. (2015). Taiwanassiminea phantasma n. sp.: a terrestrial assimineid (Caenogastropoda: Truncatelloidea) from Middle Osborn Island, Kimberley, Western Australia. Molluscan Research 35: 112-122.
Thiele, J. (1927). Über die Schneckenfamilie der Assimineidae. Zoologische Jahrbücher. Abteilung für Systematik Oekologie und Geographie der Tiere 53: 113-146.
Willan, E. C. & Kessner, V. (2021). A conspectus of the freshwater molluscs of the Daly River catchment, Northern Territory. Northern Territory Naturalist 30: 108-137.
