†subfamily Trigonoseminae Elliott 1965 (lamp shell)
Rhynchonellata - Terebratulida - Terebrataliidae
Parent taxon: Terebrataliidae according to A. Williams et al. 2006
Sister taxa: Gemmarculinae, Terebrataliinae
Subtaxa: Dereta Terebrirostra Trigonosemus
Type: Trigonosemus
Ecology: stationary low-level epifaunal suspension feeder
Distribution:
• Cretaceous of Belgium (10 collections), France (1), Kazakhstan (1), Spain (1), the United Kingdom (12)
Total: 25 collections each including a single occurrence