''Plumulites'' is an extinct genus of machaeridians, an extinct

annelid The annelids (), also known as the segmented worms, are animals that comprise the phylum Annelida (; ). The phylum contains over 22,000 extant species, including ragworms, earthworms, and leeches. The species exist in and have adapted to vario ...

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

sclerite A sclerite (Greek language, Greek , ', meaning "hardness, hard") is a hardened body part. In various branches of biology the term is applied to various structures, but not as a rule to vertebrate anatomical features such as bones and teeth. Instea ...

s, and originally considered as

arthropod Arthropods ( ) are invertebrates in the phylum Arthropoda. They possess an arthropod exoskeleton, exoskeleton with a cuticle made of chitin, often Mineralization (biology), mineralised with calcium carbonate, a body with differentiated (Metam ...

or an

echinoderm An echinoderm () is any animal of the phylum Echinodermata (), which includes starfish, brittle stars, sea urchins, sand dollars and sea cucumbers, as well as the sessile sea lilies or "stone lilies". While bilaterally symmetrical as ...

. However, complete sclerite assemblages of ''P. richorum'' described in 1979 has shown that this animal is more likely to be

worm, the group which includes modern-day

earthworm An earthworm is a soil-dwelling terrestrial invertebrate that belongs to the phylum Annelida. The term is the common name for the largest members of the class (or subclass, depending on the author) Oligochaeta. In classical systems, they we ...

leech Leeches are segmented parasitism, parasitic or Predation, predatory worms that comprise the Class (biology), subclass Hirudinea within the phylum Annelida. They are closely related to the Oligochaeta, oligochaetes, which include the earthwor ...

and

bristleworm Polychaeta () is a paraphyletic class of generally marine annelid worms, commonly called bristle worms or polychaetes (). Each body segment has a pair of fleshy protrusions called parapodia that bear many bristles, called chaetae, which are ma ...

. 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 In invertebrates, the term parapodium ( Gr. ''para'', beyond or beside + ''podia'', feet; : parapodia) refers to lateral outgrowths or protrusions from the body. Parapodia are predominantly found in annelids, where they are paired, unjointed late ...

and

chaeta A chaeta or cheta (; ) is a chitinous bristle or seta found on annelid worms, although the term is also frequently used to describe similar structures in other invertebrates such as arthropods. Polychaete annelids (''polychaeta'' literally me ...

Taxonomy

Preservation of jaw element of ''P. bengtsoni'' leads conclusion that machaeridians should be placed within the crown group of

Phyllodocida Phyllodocida is an order of polychaete worms in the subclass Aciculata. These worms are mostly marine, though some are found in brackish water. Most are active benthic creatures, moving over the surface or burrowing in sediments, or living in cr ...

Species

As of 1929, more than 20 species have been described. Subsequent studies have described many more species. * ''P. canadensis ''Woodward, 1889 (

type Type may refer to: Science and technology Computing * Typing, producing text via a keyboard, typewriter, etc. * Data type, collection of values used for computations. * File type * TYPE (DOS command), a command to display contents of a file. * ...

)

Ottawa Ottawa is the capital city of Canada. It is located in the southern Ontario, southern portion of the province of Ontario, at the confluence of the Ottawa River and the Rideau River. Ottawa borders Gatineau, Gatineau, Quebec, and forms the cor ...

Canada Canada is a country in North America. Its Provinces and territories of Canada, ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, making it the world's List of coun ...

Katian The Katian is the second stage of the Upper Ordovician. It is preceded by the Sandbian and succeeded by the Hirnantian Stage. The Katian began million years ago and lasted for about 7.6 million years until the beginning of the Hirnantian mill ...

(Upper

Ordovician The Ordovician ( ) is a geologic period and System (geology), system, the second of six periods of the Paleozoic Era (geology), Era, and the second of twelve periods of the Phanerozoic Eon (geology), Eon. The Ordovician spans 41.6 million years f ...

) * ''P. australis'' Talent, 1963 * ''P. bengtsoni'' Vinther, Van Roy & Briggs, 2008

Fezouata Formation The Fezouata Formation or Fezouata Shale is a geological formation in Morocco which dates to the Ordovician, Early Ordovician.

Morocco Morocco, officially the Kingdom of Morocco, is a country in the Maghreb region of North Africa. It has coastlines on the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria to Algeria–Morocc ...

, Upper

Tremadocian The Tremadocian is the lowest stage of Ordovician. Together with the later Floian Stage it forms the Lower Ordovician Epoch. The Tremadocian lasted from to million years ago. The base of the Tremadocian is defined as the First appearance datum ...

(Lower Ordovician) * ''P. bohemicus'' Barrande, 1868

Bohemia Bohemia ( ; ; ) is the westernmost and largest historical region of the Czech Republic. In a narrow, geographic sense, it roughly encompasses the territories of present-day Czechia that fall within the Elbe River's drainage basin, but historic ...

Czech Republic The Czech Republic, also known as Czechia, and historically known as Bohemia, is a landlocked country in Central Europe. The country is bordered by Austria to the south, Germany to the west, Poland to the northeast, and Slovakia to the south ...

, Lower Ordovician * ''P. chikunensis'' Kobayashi, 1934 Chikunsan shale (Jigunsan Formation),

South Korea South Korea, officially the Republic of Korea (ROK), is a country in East Asia. It constitutes the southern half of the Korea, Korean Peninsula and borders North Korea along the Korean Demilitarized Zone, with the Yellow Sea to the west and t ...

, Llandeilian (Middle Ordovician) * ''"P". clarki'' Shaw, 1966 (=?''P. mobergi'' Clark, 1924) Highgate Formation,

Vermont Vermont () is a U.S. state, state in the New England region of the Northeastern United States. It borders Massachusetts to the south, New Hampshire to the east, New York (state), New York to the west, and the Provinces and territories of Ca ...

, USA, Lower Ordovician * ''P. compar'' Barrande, 1872 Bohemia, Czech Republic, Lower Ordovician * ''P. contarius'' Barrande, 1872 Bohemia, Czech Republic, Lower Ordovician * ''P. dalecarlicus'' Moberg, 1914

Scania Scania ( ), also known by its native name of Skåne (), is the southernmost of the historical provinces of Sweden, provinces () of Sweden. Located in the south tip of the geographical region of Götaland, the province is roughly conterminous w ...

Sweden Sweden, formally the Kingdom of Sweden, is a Nordic countries, Nordic country located on the Scandinavian Peninsula in Northern Europe. It borders Norway to the west and north, and Finland to the east. At , Sweden is the largest Nordic count ...

, Middle Ordovician * ''P. delicatus'' Barrande, 1872 Bohemia, Czech Republic, Lower

Silurian The Silurian ( ) is a geologic period and system spanning 23.5 million years from the end of the Ordovician Period, at million years ago ( Mya), to the beginning of the Devonian Period, Mya. The Silurian is the third and shortest period of t ...

* ''P. devonicus'' J. M. Clarke, 1882 Hamilton group,

New York New York most commonly refers to: * New York (state), a state in the northeastern United States * New York City, the most populous city in the United States, located in the state of New York New York may also refer to: Places United Kingdom * ...

, USA, Middle

Devonian The Devonian ( ) is a period (geology), geologic period and system (stratigraphy), system of the Paleozoic era (geology), era during the Phanerozoic eon (geology), eon, spanning 60.3 million years from the end of the preceding Silurian per ...

* ''P. discretus'' Barrande, 1872 Bohemia, Czech Republic, Lower Silurian * ''P. esthonicus'' Withers, 1921 Jewe Station, Esthonia, Middle Ordovician * ''P. eueides'' Högström ''et al.'', 2008 Boda Limestone, Siljan district, Sweden, Lower Ordovician (Katian–

Hirnantian The Hirnantian is the final internationally recognized stage of the Ordovician Period of the Paleozoic Era. It was of short duration, lasting about 2.1 million years, from to Ma (million years ago). The early part of the Hirnantian was char ...

) * ''P. folliculum'' Barrande, 1868 Bohemia, Czech Republic, Lower Ordovician * ''P. fraternus'' Barrande, 1872 Bohemia, Czech Republic, Middle Ordovician * ''P. gracillimus'' Ringueberg, 1888

Rochester Shale The Clinton Group (also referred to as the Clinton Formation or the Clinton Shale) is a mapped unit of sedimentary rock found throughout eastern North America. The interval was first defined by the geologist Lardner Vanuxem, who derived the name ...

, New York, USA, Middle Silurian * ''P. gumunsoensis'' Choi & Kim, 1989 Dumugol Formation, South Korea, Upper Tremadocian * ''P. kutscheri'' Schrank, 1978

Germany Germany, officially the Federal Republic of Germany, is a country in Central Europe. It lies between the Baltic Sea and the North Sea to the north and the Alps to the south. Its sixteen States of Germany, constituent states have a total popu ...

, Upper

Wenlock Epoch The Wenlock Epoch (sometimes referred to as the Wenlockian) is the second epoch of the Silurian. It is preceded by the Llandovery Epoch and followed by the Ludlow Epoch. Radiometric dates constrain the Wenlockian between and million years ago. ...

(Silurian) * ''P. lamonti'' Candela & Crighton, 2017 Law Linn Formation,

Pentland Hills The Pentland Hills are a range of hills southwest of Edinburgh, Scotland. The range is around in length, and runs southwest from Edinburgh towards Biggar and the upper Clydesdale. Etymology The hills take their name from the hamlet of Pe ...

Scotland Scotland is a Countries of the United Kingdom, country that is part of the United Kingdom. It contains nearly one-third of the United Kingdom's land area, consisting of the northern part of the island of Great Britain and more than 790 adjac ...

Telychian In the geologic timescale, the Telychian is the third and final age of the Llandovery Epoch of the Silurian Period of the Paleozoic Era of the Phanerozoic Eon. The Telychian Age was between 438.5 ± 1.2 million years ago (Ma) and 433.4 ± 0.8 M ...

(Silurian) * ''P. llanvirnensis'' Withers & Henry, 1926

Pembrokeshire Pembrokeshire ( ; ) is a Principal areas of Wales, county in the South West Wales, south-west of Wales. It is bordered by Carmarthenshire to the east, Ceredigion to the northeast, and otherwise by the sea. Haverfordwest is the largest town and ...

Wales Wales ( ) is a Countries of the United Kingdom, country that is part of the United Kingdom. It is bordered by the Irish Sea to the north and west, England to the England–Wales border, east, the Bristol Channel to the south, and the Celtic ...

, United Kingdoms, Skiddavian (Lower Ordovician) * ''P. malayensis'' Kobayashi & Hamada, 1976 Pulau Langgon, Langkawi Islands,

Malaysia Malaysia is a country in Southeast Asia. Featuring the Tanjung Piai, southernmost point of continental Eurasia, it is a federation, federal constitutional monarchy consisting of States and federal territories of Malaysia, 13 states and thre ...

, Upper Ordovician * ''P. minumus'' Barrande, 1872 Bohemia, Czech Republic, Lower Silurian * ''P. mitchelli'' R. Etheridge, 1890 Bowning Creek,

New South Wales New South Wales (commonly abbreviated as NSW) is a States and territories of Australia, state on the Eastern states of Australia, east coast of :Australia. It borders Queensland to the north, Victoria (state), Victoria to the south, and South ...

Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...

, ?Wenlock Epoch (Silurian) * ''P. mobergi'' T. H. Clark, 1924

Quebec Quebec is Canada's List of Canadian provinces and territories by area, largest province by area. Located in Central Canada, the province shares borders with the provinces of Ontario to the west, Newfoundland and Labrador to the northeast, ...

, Canada, Lower Ordovician * ''P. ornatus'' Chapman, 1910

Victoria Victoria most commonly refers to: * Queen Victoria (1819–1901), Queen of the United Kingdom and Empress of India * Victoria (state), a state of Australia * Victoria, British Columbia, Canada, a provincial capital * Victoria, Seychelles, the capi ...

, Australia, Melbournian (Silurian) * ''P. peachi'' Nicholson & Etheridge, 1880

Ayrshire Ayrshire (, ) is a Counties of Scotland, historic county and registration county, in south-west Scotland, located on the shores of the Firth of Clyde. The lieutenancy areas of Scotland, lieutenancy area of Ayrshire and Arran covers the entirety ...

, Scotland,

Ashgillian The Ordovician ( ) is a geologic period and system, the second of six periods of the Paleozoic Era, and the second of twelve periods of the Phanerozoic Eon. The Ordovician spans 41.6 million years from the end of the Cambrian Period Ma (millio ...

(Upper Ordovician) * ''P. primus'' Kobayashi, 1934 Dumugol Formation, South Korea, Upper Tremadocian * ''P. pygmaeus'' Moberg, 1914

Dalarna Dalarna (; ), also referred to by the English exonyms Dalecarlia and the Dales, is a (historical province) in central Sweden. Dalarna adjoins Härjedalen, Hälsingland, Gästrikland, Västmanland and Värmland. It is also bordered by Nor ...

, Sweden, Lower Silurian * ''P. rastritum'' Moberg, 1914 Dalarna, Sweden, Lower Silurian * ''P. regius'' Barrande, 1872 Bohemia, Czech Republic, Middle-Upper Ordovician * ''P. richorum'' Jell, 1979 Humevale Formation, Victoria, Australia, Early Devonian * ''P. ruskini'' Lamont, 1978 Wether Law Linn Formation, Pentland Hills, Scotland, Telychian (Silurian) * ''P. scoticus'' R. Etheridge, 1878 Balclatchie group, Ayrshire, Scotland, Caradocian (Upper Ordovician) * ''P. tafennaensis'' Chauvel, 1967 Morocco,

Caradoc Caradoc Vreichvras (; Modern , ) was a semi-legendary ancestor to the kings of Gwent. He may have lived during the 5th or 6th century. He is remembered in the Matter of Britain as a Knight of the Round Table, under the names King Carados and C ...

(Upper Ordovician) and Tafilalt Biota, Morocco, Katian (Upper Ordovician) * ''P. törnquisti'' Moberg, 1914 Dalarna, Sweden, Middle Ordovician * ''P. trentonensis'' Withers & Henry, 1926 Middle Trenton Beds, New York, USA, Middle Ordovician * ''P. yeringiae'' Chapman, 1910 Victoria, Australia, Yeringian (Silurian)

References

External links

* {{Taxonbar, from1=Q7205490, from2=Q21291236 Prehistoric annelid genera Fossils of the Czech Republic Letná Formation Fezouata Formation fossils Fossil taxa described in 1889 Devonian genus extinctions Annelids