Rhynchonellata - Pentamerida - Syntrophiidae
Parent taxon: Porambonitoidea according to A. Williams et al. 2002
See also Benedetto et al. 2003 and Opik 1934
Sister taxa: Clarkellidae, Eostrophiidae, Huenellidae, Tetralobulidae
Subtaxa: Syntrophiinae Xenelasmatinae
Type: Syntrophia
Ecology: stationary epifaunal suspension feeder
Distribution:
• Silurian of Bolivia (1 collection)
• Whiterockian of United States (2: Nevada)
• Arenig of China (2)
• Arenigian of the Russian Federation (1)
• Ordovician of Argentina (1), Canada (1: Alberta), the Russian Federation (2), the United Kingdom (1), United States (3: Nevada, Texas)
• Canadian of United States (1: Maryland)
• Tremadoc of Argentina (4), China (1)
• Ibexian of United States (1: Nevada)
• Ordian of Australia (1)
Total: 22 collections each including a single occurrence