billingsellacean
English edit
Noun edit
billingsellacean (plural billingsellaceans)
- (zoology) Any brachiopod of the superfamily Billingsellacea.
- 1979, Michael Robert House, The Origin of major invertebrate groups, page 235:
- The Obolellida and the basic articulate stock, the billingsellaceans, appear later in the lower Cambrian. The orthide billingsellaceans with their strophic hinge lines, deltidiodont dentition and invariably calcareous shells, comprise two families which, although morphologically similar, have a fundamentally different style of shell secretion, reflected in their various descendants.