Hyolitha - Orthothecida - Orthothecidae
Full reference: V. A. Syssoiev. 1957. To the morphology, systematics and systematic position of hyoliths. Akademiya Nauk S.S.S.R. 116:304-307
Parent taxon: Orthothecida according to J. M. Malinky 1990
See also Fisher 1962 and Rozanov et al. 1969
Sister taxa: Aldanothecidae, Allathecidae, Ancheilotheca, Bolitheca, Brevitheca, Bucanotheca, Carinitheca, Chelsonella, Circothecidae, Cupitheca, Curtitheca, Ebianotheca, Eogloborilus, Eonovitatus, Girvanolithes, Gracilithecidae, Grandicornus, Hexitheca, Inflaticornus, Isititheca, Khetatheca, Kotuyitheca, Lophotheca, Minitheca, Mooritheca, Neobactrotheca, Nikatheca, Novitatidae, Panitheca, Paragloborilus, Petasotheca, Plicitheca, Probactrotheca, Renitheca, Sysoievia, Tchuranitheca, Tetratheca, Tetrathecidae, Triplicatellidae, Turcutheca
Subtaxa: Bactrotheca Lenatheca Lentitheca Orthotheca Quadrotheca Semielliptotheca Trapezotheca
Ecology: stationary epifaunal suspension feeder
Distribution:
• Devonian of Australia (1 collection), the Czech Republic (2), Germany (1), Morocco (9), South Africa (5), United States (1: Pennsylvania)
• Silurian of Australia (1), the Czech Republic (1)
• Dobrotivian of the Czech Republic (1)
• Arenig of Argentina (1)
• Ordovician of China (2), the Czech Republic (2), Poland (1), Sweden (2), the United Kingdom (8)
• Tremadoc of Argentina (1), France (2), Spain (1), Sweden (1)
• Cressagian of the United Kingdom (1)
• Amgan of Norway (1)
• Solvan of Sweden (2)
• Delamaran of United States (2: Idaho)
• Cambrian of Canada (3: Quebec), China (2), Germany (1), Greenland (3), Mexico (1), the Russian Federation (10), the United Kingdom (1), United States (6: New York, Vermont)
Total: 76 collections including 89 occurrences