Belongs within: Pentamerida.
The Pentameridae were a family of brachiopods that lived from the Upper Ordovician to the Lower Devonian (Amsden & Biernat 1965). In some genera, such as Conchidium and Lissocoelina, the pedicle valve is distinctly rostrate, arching over the brachial valve. The Silurian genus Pentamerus was large and elongate, with a smooth surface (Amsden & Biernat 1965).
Characters (from Amsden & Biernat 1965, as Pentamerinae): Moderate to large size, with smooth, costate or costellate shells generally lacking well-developed interareas; fold and sulcus absent or weakly developed. Brachial processes long, rodlike; outer plates commonly discrete, but in a few genera uniting to make cruralium.
<==Pentameridae [Pentamerinae]HB93
| i. s.: TscherkidiumHB93
| Jolvia Sapelnikov 1960AB65
| `--*J. multiplexa Sapelnikov 1960AB65
| Proconchidium Rukavishnikova & Sapelnikov 1973HB93, RZJ04
| `--P. muensteri (St. Joseph 1938)HB93
|--Aliconchidium St. Joseph 1942B75, AB65
| `--*A. yassi St. Joseph 1942AB65
|--Cymbidium Kirk 1926B75, AB65
| `--*C. actum Kirk 1926AB65
|--+--Eoconchidium Rozman 1967B75, RZJ04
| `--Pseudoconchidium Nikiforova & Sapelnikov 1971B75, RZJ04
|--Conchidium Oehlert 1887B75, AB65
| |--*C. biloculare (Hisinger 1799) [=Anomia bilocularis]AB65
| |--C. alaskenseAB65
| |--C. etheridgei (Dun 1907) [=Pentamerus (Conchidium) etheridgei]F71
| |--C. knightii [=Pentamerus knightii; incl. C. knightii var. stricta]F71
| |--C. munsteri St. Joseph 1937AB65
| |--C. occidentale (Hall 1852) [=Pentamerus occidentalis]AB65
| `--C. vogulicumAB65
|--+--Pentamerus Sowerby 1813B75, M03 (see below for synonymy)
| | |--*P. oblongus Sowerby in Murchison 1839AB65 [incl. P. samojedicus Keyserling 1846M03, Borealis samojedicusM03]
| | |--P. costatus Etheridge 1892F71
| | |--P. galeatusM87
| | `--P. hospesF71
| `--+--BisulcatellaB75
| |--SapelnikoviaB75
| |--Pentameroides Schuchert & Cooper 1931B75, AB65
| | `--*P. subrectus (Hall & Clarke 1894) [=Pentamerus oblongus subrectus]AB65
| `--Callipentamerus Boucot 1964B75, M65
| `--*C. corrugatus (Weller & Davidson 1896) [=Pentamerus corrugatus]M65
`--+--+--EopentameriferaB75
| `--Pentamerifera Khodalevich 1939B75, AB65
| `--*P. taltiensis (Chernyshev 1893) [=Pentamerus taltiensis]AB65
|--Borealis Boucot, Johnson & Staton 1971B75, M03
| |--*B. borealis (Eichwald 1842)M03
| | |--B. b. borealisM03
| | `--B. b. osloensis Mørk 1981M03
| |--B. cristiformis (Modzalevskaya 1985) [=Pentamerus cristiformis]M03
| `--B. schmidti (Lebedev 1892)M03
|--+--CarmanellaB75
| |--StenopentamerusB75
| |--Lissocoelina Schuchert & Cooper 1931B75, AB65
| | `--*L. pergibbosa (Hall & Whitfield 1875) [=Pentamerus pergibbosus]AB65
| `--Harpidium Kirk 1925 non Körb. 1855 (ICBN)B75, M03
| |--*H. insigne (Kirk 1925) [=H. insignis]AB65
| `--H. angustum Poulsen 1943M03
`--+--Bisulcata indianensis Boucot & Johnson 1979B75, HB93
|--+--PinguaellaB75
| `--Kirkidium Amsden, Boucot & Johnson 1967B75, RZJ04
|--+--PararhipidiumB75
| `--KhodalevitchiaB75
|--+--EctorhipidiumB75
| `--Rhipidium Schuchert & Cooper 1931 nec Wallr. 1833 (ICBN) nec Cornu 1871 (ICBN)B75, AB65
| `--*R. knappi (Hall & Whitfield 1872) [=Pentamerus knappi]AB65
`--+--Capelliniella Strand 1928B75, AB65 [=Capellinia Hall & Clarke 1894 non Trichese 1874AB65]
| `--*C. mira (Hall & Clarke 1894) [=*Capellinia mira]AB65
`--Brooksina Kirk 1922B75, AB65
`--*B. alaskensis Kirk 1922AB65
Nomen rejiciendum: Pentamerus laevis Sowerby 1813AB65
Pentamerus Sowerby 1813B75, M03 [incl. Grypidia Dalman 1828 (nom. rej.)AB65, Miopentamerus Alexander 1936 (nom. rej.)AB65, Trimurus Caldwell 1934 (nom. rej.)AB65]
*Type species of generic name indicated
References
[AB65] Amsden, T. W., & G. Biernat. 1965. Pentamerida. In: Moore, R. C. (ed.) Treatise on Invertebrate Paleontology pt H. Brachiopoda vol. 2 pp. H523–H552. The Geological Society of America, Inc.: Boulder (Colorado), and The University of Kansas Press: Lawrence (Kansas).
[B75] Boucot, A. J. 1975. Evolution and Extinction Rate Controls. Elsevier Scientific Publishing Company.
[F71] Fletcher, H. O. 1971. Catalogue of type specimens of fossils in the Australian Museum, Sydney. Australian Museum Memoir 13: 1–167.
[HB93] Harper, D. A. T., C. H. C. Brunton, L. R. M. Cocks, P. Copper, E. N. Doyle, A. L. Jeffrey, E. F. Owen, M. A. Parkes, L. E. Popov & C. D. Prosser. 1993. Brachiopoda. In: Benton, M. J. (ed.) The Fossil Record 2 pp. 427–462. Chapman & Hall: London.
[M87] Mitchell, J. 1887. Notes on the geology of Bowning, N.S.W. Proceedings of the Linnean Society of New South Wales, series 2, 1 (4): 1193–1204.
[M03] Modzalevskaya, T. L. 2003. Silurian and Devonian brachiopods from Severnaya Zemlya (Russian Arctic). Geodiversitas 25 (1): 73–107.
[M65] Moore, R. C. (ed.) 1965. Treatise on Invertebrate Paleontology pt H. Brachiopoda vol. 2. The Geological Society of America, Inc.: Boulder (Colorado), and The University of Kansas Press: Lawrence (Kansas).
[RZJ04] Rong, J.-Y., R.-B. Zhan & J. Jin. 2004. The Late Odovician and Early Silurian pentameride brachiopod Holorhynchus Kiaer, 1902 from north China. Journal of Paleontology 78 (2): 287–299.