Borealis cristiformis, from Modzalevskaya (2003).

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.

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, AB65 (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
       |  `--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
       |  |--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
          |  `--Kirkidium Amsden, Boucot & Johnson 1967B75, RZJ04
          |  `--KhodalevitchiaB75
          |  `--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, AB65 [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


[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.

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