Lower Cambrian (upper Atdabanian) – Holocene
Lingulida is an extant order of stationary, low-level, epifaunal suspension feeders.
Characteristics of the Order
- Smooth or pitted micro-ornamented shell
- Inarticulate brachiopod
- Musculature involves single or paired umbonal muscles
- Baculate or bifurcate mantle canal system
Treatise on Invertebrate Paleontology, Part H, Vol. 2 (2000):
- Larval shell usually large (more than 0.3 mm across), smooth or with pitted micro-ornamentation; pedicle emerging posteriorly between valves or through foramen; musculature composed of single or paired umbonal muscle (posterior adductor in Discinoidea), three or four pairs of oblique muscles, and paired central muscles (anterior adductor in Discinoidea); mantle canal system baculate or bifurcate; dorsal vascula media usually developed; shell structure with baculate laminae.