Belongs within: Mangeliidae. Dazed and Cythara Published 19 August 2026 I’ve had occasion multiple times on this site to comment on the taxonomic complications surrounding the conoid gastropods, ‘turrids’ in the broad sense. Nevertheless, among the more complicated cases is that of the genus name Cythara. Cythara striata was established by Christian Schumacher in 1817 for a… Continue reading Eucithara
Category: Mollusca
Scoliostomatidae
Belongs within: Gastropoda. The Scoliostomatidae are a Devonian family of gastropods with a distinctive shell morphology: at maturity, the last whorl of the shell twists outwards and backwards, so its apparent position is reversed relative to the rest of the shell. This gerontic whorl also turns upwards in members of the subfamily Scoliostomatinae but not… Continue reading Scoliostomatidae
Monoplacophora
Belongs within: Mollusca.Contains: Kirengellida, Tryblidiida, Cyrtolitidae. The Monoplacophora are a group of molluscs with simple, often cap-shaped shells and an exogastric, untorted organisation. Living representatives exhibit internal metamerism, which may be represented in fossil forms by a series of pairs of muscle scars. <==Monoplacophora | i. s.: Pseudomyona queenslandicaBRW98 |–Tergomya [Pilinea]BR17 | |–KirengellidaBR17 | `–TryblidiidaBR17 |–Cyrtonellidae [Cyrtonellacea,… Continue reading Monoplacophora
Gastropoda
Belongs within: Mollusca.Contains: Scoliostomatidae, Caseolus, Leiostyla, Clisospiroidea, Bellerophontoidea, Archinacelloidea, Pelagielloidea, Macluritida, Neomphaliones, Patellogastropoda, Vetigastropoda, Neritimorpha, Loxonematoidea, Heterobranchia, Peruneloidea, Cyclophoroidea, Ampullariidae, Viviparoidea, Orthonematoidea, Subulitoidea, Soleniscidae, Meekospiridae, Cerithiimorpha, Hypsogastropoda. The Gastropoda, snails and slugs, are a major clade of molluscs characterised by the process of torsion during larval development with the visceral mass and mantle becoming turned… Continue reading Gastropoda
Archinacelloidea
Belongs within: Gastropoda. The Archinacelloidea are an Ordovician to Silurian group of low, spoon-shaped shells with the apex anterior and just overhanging the margin of the aperture. <==Archinacelloidea [Archinacellacea]GS75 |–Archaeopraga Horný 1963 [Archaeopragidae]BR05 | `–*A. pinnaeformis (Perner 1903) [=Helcionopsis pinnaeformis]BR17 `–ArchinacellidaeBR05 |–BarrandicellaBR05 |–Archinacellopsis patelliformisGS75 |–Floripatella rousseaui Yochelson 1988TTE93 |–Guelphinacella canadense (Whiteaves 1884)TTE93 `–Archinacella Ulrich & Scofield… Continue reading Archinacelloidea
Pterothecidae
Belongs within: Bellerophontoidea. The Pterothecidae are an Ordovician to Devonian group of bellerophontoids with a rapidly expanding shell bearing a more or less developed plate at the aperture, and a selenizone on a dorsal crest (Knight et al. 1960). PterothecidaeBR05 |–Pedasiola Spriesterbach 1919 [Pedasiolinae]BR05 | `–*P. rhenana Spriestersbach 1919KC60 |–PterothecinaeBR05 | |–Cyclotheca Teichert 1935 non Theiss. 1914 (ICBN)KC60… Continue reading Pterothecidae
Bellerophontoidea
Belongs within: Gastropoda.Contains: Euphemitinae, Tropidodiscidae, Pterothecidae, Knightitinae, Bellerophontinae, Bucaniinae, Sinuitidae. The Bellerophontoidea are a lineage of coiled molluscs known from the Upper Cambrian to the Lower Triassic. The shell is isostrophic, superficially similar to a small nautiloid, with a median emargination or tremata (Knight et al. 1960). The bellerophontoids have most commonly been presumed to… Continue reading Bellerophontoidea
Sinuitidae
Belongs within: Bellerophontoidea. The Sinuitidae are a group of involute to partly evolute planispiral bellerophontoids with a posterior apertural sinus or broad slit, known from the early Late Cambrian to the Early Triassic (Runnegar & Jell 1976). Sinuitidae [Sinuitoidea]BR05 | i. s.: Cloudia Knight 1947RJ76 | `–*C. buttsi Knight 1947KC60 | Gamadiscus Horny 1962RJ76 | Strepsodiscus… Continue reading Sinuitidae
Cyrtolitidae
Belongs within: Monoplacophora. The Cyrtolitidae are a group of molluscs with generally openly coiled shells known from the Upper Silurian to the Lower Devonian. The anal emargination forms a shallow sinus that is commonly angular but does not lead to a slit or selenizone (Knight et al. 1960). <==Cyrtolitidae [Cyrtolitida, Procarinariidae] | i. s.: Procarinaria Perner 1911KC60 |… Continue reading Cyrtolitidae
Scutellastra
Belongs within: Patellogastropoda. Scutellastra is a genus of limpets bearing rather massive shells with an opaque, non-iridescent porcellaneous interior, and having the median central radular tooth well developed (Wilson 1993). <==Scutellastra Adams & Adams 1854 [incl. Patellanax Iredale 1924, Penepatella Iredale 1929]W93 | i. s.: S. soyaensis (Kase & Shigeta 1996) [=Patella soyaensis]NO04 |–+–S. mexicana (Broderip &… Continue reading Scutellastra