Rhynchonelliformea
Rhynchonelliformea is a major subphylum and clade of brachiopods. It is roughly equivalent to the former class Articulata, which was used previously in brachiopod taxonomy up until the 1990s. These so-called articulated brachiopods have many anatomical differences relative to "inarticulate" brachiopods of the subphyla Linguliformea and Craniformea. Articulates have hard calcium carbonate shells with tongue-and-groove hinge articulations (hence the name) and separate sets of simple opening and closing muscles.
| Rhynchonelliformea Temporal range: Lower Cambrian to Recent | |
|---|---|
| Burmirhynchia jirbaensis, a rhynchonellide from the Jurassic of Israel | |
| Scientific classification | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Brachiopoda |
| Subphylum: | Rhynchonelliformea Williams, Carlson, Brunton, Holmer & Popov, 1996 |
| Classes | |
The Rhynchonelliformea (as described in the Treatise Part H, revised 1997–2007) is divided into five classes: Obolellata, Kutorginata, Chileata, Strophomenata, and Rhynchonellata. The Rhynchonellata are found living today, as the major constituent of modern brachiopod faunas. The other classes are all extinct: the Obolellata and Kutorginata are restricted to the Cambrian, while the Chileata and Strophomenata range through most of the Paleozoic.