Plumulites
Plumulites is an extinct genus of machaeridians, an extinct annelid group.
Description
Plumulites is normally small animal, for example complete specimen of P. canadensis reached only, and P. bengtsoni being. However, several largest specimens probably reached around, making Plumulites largest machaeridians ever known.
Fossils of Plumulites were mostly known from isolated sclerites, and originally considered as arthropod or an echinoderm. However, complete sclerite assemblages of P. richorum described in 1979 has shown that this animal is more likely to be annelid worm, the group which includes modern-day earthworm, leech and bristleworm.
According to complete specimens, this animal is surrounded by pairs of outer and interior shell plates. Some of anterior outer and interior shell plates different in shape. Specimen of P. bengtsoni shows soft tissue including parapodia and chaetae.
Taxonomy
Preservation of jaw element of P. bengtsoni leads conclusion that machaeridians should be placed within the crown group of Phyllodocida.
Species
As of 1929, more than 20 species have been described. Subsequent studies have described many more species.P. canadensis Woodward, 1889 Ottawa, Canada, Katian P. australis Talent, 1963P. bengtsoni Vinther, Van Roy & Briggs, 2008 Fezouata Formation, Morocco, Upper Tremadocian P. bohemicus Barrande, 1868 Bohemia, Czech Republic, Lower OrdovicianP. chikunensis Kobayashi, 1934 Chikunsan shale, South Korea, Llandeilian "P". clarki Shaw, 1966 Highgate Formation, Vermont, USA, Lower OrdovicianP. compar Barrande, 1872 Bohemia, Czech Republic, Lower OrdovicianP. contarius Barrande, 1872 Bohemia, Czech Republic, Lower OrdovicianP. dalecarlicus Moberg, 1914 Scania, Sweden, Middle OrdovicianP. delicatus Barrande, 1872 Bohemia, Czech Republic, Lower SilurianP. devonicus J. M. Clarke, 1882 Hamilton group, New York, USA, Middle DevonianP. discretus Barrande, 1872 Bohemia, Czech Republic, Lower SilurianP. esthonicus Withers, 1921 Jewe Station, Esthonia, Middle OrdovicianP. eueides Högström et al., 2008 Boda Limestone, Siljan district, Sweden, Lower Ordovician P. folliculum Barrande, 1868 Bohemia, Czech Republic, Lower OrdovicianP. fraternus Barrande, 1872 Bohemia, Czech Republic, Middle OrdovicianP. gracillimus Ringueberg, 1888 Rochester Shale, New York, USA, Middle SilurianP. gumunsoensis Choi & Kim, 1989 Dumugol Formation, South Korea, Upper TremadocianP. kutscheri Schrank, 1978 Germany, Upper Wenlock Epoch P. lamonti Candela & Crighton, 2017 Law Linn Formation, Pentland Hills, Scotland, Telychian P. llanvirnensis Withers & Henry, 1926 Pembrokeshire, Wales, United Kingdoms, Skiddavian P. malayensis Kobayashi & Hamada, 1976 Pulau Langgon, Langkawi Islands, Malaysia, Upper OrdovicianP. minumus Barrande, 1872 Bohemia, Czech Republic, Lower SilurianP. mitchelli R. Etheridge, 1890 Bowning Creek, New South Wales, Australia, ?Wenlock Epoch P. mobergi T. H. Clark, 1924 Quebec, Canada, Lower OrdovicianP. ornatus Chapman, 1910 Victoria, Australia, Melbournian P. peachi Nicholson & Etheridge, 1880 Ayrshire, Scotland, Ashgillian P. primus Kobayashi, 1934 Dumugol Formation, South Korea, Upper TremadocianP. pygmaeus Moberg, 1914 Dalarna, Sweden, Lower SilurianP. rastritum Moberg, 1914 Dalarna, Sweden, Lower SilurianP. regius Barrande, 1872 Bohemia, Czech Republic, Middle-Upper OrdovicianP. richorum Jell, 1979 Humevale Formation, Victoria, Australia, Early DevonianP. ruskini Lamont, 1978 Wether Law Linn Formation, Pentland Hills, Scotland, Telychian P. scoticus R. Etheridge, 1878 Balclatchie group, Ayrshire, Scotland, Caradocian P. tafennaensis Chauvel, 1967 Morocco, Caradoc and Tafilalt Biota, Morocco, Katian P. törnquisti Moberg, 1914 Dalarna, Sweden, Middle OrdovicianP. trentonensis Withers & Henry, 1926 Middle Trenton Beds, New York, USA, Middle OrdovicianP. yeringiae Chapman, 1910 Victoria, Australia, Yeringian