Asaphus

Extinct genus of trilobites


title: "Asaphus" type: doc version: 1 created: 2026-02-28 author: "Wikipedia contributors" status: active scope: public tags: ["asaphida-genera", "ordovician-trilobites-of-europe", "fossils-of-estonia", "fossils-of-russia", "fossils-of-sweden", "early-ordovician-first-appearances", "middle-ordovician-extinctions", "taxa-named-by-alexandre-brongniart", "floian", "dapingian", "darriwilian", "fossil-taxa-described-in-1822", "asaphidae"] description: "Extinct genus of trilobites" topic_path: "geography/russia" source: "https://en.wikipedia.org/wiki/Asaphus" license: "CC BY-SA 4.0" wikipedia_page_id: 0 wikipedia_revision_id: 0

::summary Extinct genus of trilobites ::

| fossil_range = | image = Asaphus latus frontal.jpg | image_caption = A. latus | taxon = Asaphus | authority = Brongniart, 1822 | subdivision_ranks = Species | subdivision =

Asaphus () is a genus of trilobites that is known from the Lower (upper Arenig) and Middle Ordovician of northwestern Europe (Sweden, Estonia, Saint Petersburg Area).

Etymology

The generic name is derived from the Greek word asaphes, meaning "indistinct."

Description

::figure[src="https://upload.wikimedia.org/wikipedia/commons/2/29/Asaphus_plautini_oblique_frontal.jpg" caption="isopygous]])."] ::

The central raised area of the cephalon (or glabella) is long, reaching the frontal margin. It may have faint lateral glabellar furrows or be smooth, and sometimes an inconspicuous tubercle is present just in front of the hardly discernible occipital ring. The natural fracture lines (sutures) of the head run along the top edges of the compound eye. From the back of the eye these cut to the back of the head (or is said to be opisthoparian) and not to the side. The free cheeks (or librigenae) are separated from each other anteriorly by a suture at the midline. The corner between the side and the back of the cephalon (or genal angle) is rounded or (in a few species) pointed into spines. Eyes holochroal, commonly more or less conical, short or moderate in length. In some evolution lines, the visual surface of the eye is raised on a stalk.

The lateral corners of the palate (or hypostome), visual from the ventral side, are more or less protruding, and the posterior part is forked with two triangular teeth. The reflexed margin of the exoskeleton (or doublure) is broad.

The articulate midlength part of the body (or thorax) consists of 8 segments. Furrows in the parts outside the axis (or pleural furrows) are diagonal.

The pygidium is rounded, and has a long axis with concave, posteriorly parallel sides. Some rings may be faintly defined anteriorly and the axis dissolves in the postaxial field. The areas outside the axis (or pleural fields) are smooth or very faintly ribbed.

Species

::figure[src="https://upload.wikimedia.org/wikipedia/commons/0/03/Asaphus_kowalewskii_lateral_overlapeyes.jpg" caption="A. kowalewskii]]''"] ::

  • A. expansus (Wahlenberg, [1818]) (type species) synonyms Entomostracites expansus, Entomolithus paradoxus α expansus
  • A. acuminatus Boeck, 1838
  • A. bottnicus Jaanusson
  • A. broeggeri Schmidt, 1898
  • A. cornutus Pander, 1830
  • A. eichwaldi Schmidt
  • A. heckeri (Ivantsov)
  • A. holmi Schmidt, 1898
  • A. ingrianus Jaanusson, 1953
  • A. intermedius Lessnikova in Balashova, 1953
  • A. knyrkoi Schmidt
  • A. kotlukovi Lessnikova in Balashova, 1953
  • A. kowalewskii Lawrow, 1856
  • A. latus Pander, 1830
  • A. laevissimus Schmidt, 1898
  • A. lepidurus Neiszkowski, 1859
  • A. minor
  • A. neiszkowskii Schmidt, 1898
  • A. pachyophthalmus
  • A. platycephalus (Stokes, 1824)
  • A. plautini Schmidt, 1898
  • A. punctatus Lessnikova, 1949
  • A. raniceps Dalman, 1827
  • A. robustus
  • A. sulvevi Jaanusson
  • A. vicarius (Toernquist, 1884)
  • A. wahlenbergi

Species previously assigned to ''Asaphus''

::figure[src="https://upload.wikimedia.org/wikipedia/commons/8/89/Asaphus_expansus_ventral.jpg" caption="isbn= 978-0-8137-3015-8}}"] ::

References

References

  1. Martin Stein & Jan Bergström. (2010). "Some lower Middle Ordovician species of ''Asaphus'' (Trilobita) from Sweden". [[GFF (journal).
  2. Moore, R.C.. (1959). "Arthropoda I - Arthropoda General Features, Proarthropoda, Euarthropoda General Features, Trilobitomorpha". Geological Society of America/University of Kansas Press.
  3. International Commission on Zoological Nomenclature. (1982). "Direction 111 - ''Entomostracites punctatus'' Wahlenberg (Trilobita) (Official List Of Specific Names No. 1595): Date To Be Cited As [1818]". Bulletin of Zoological Nomenclature.
  4. White, Charles Abiathar. (1891). "The Texan Permian and Its Mesozoic Types of Fossils". [[United States Geological Survey]].
  5. Moore, R.C.. (1959). "Arthropoda I - Arthropoda General Features, Proarthropoda, Euarthropoda General Features, Trilobitomorpha". Geological Society of America/University of Kansas Press.
  6. Osmólska, H.. (1970). "Revision of non-cyrtosymbolinid trilobites from the Tournaisian-Namurian of Eurasia". Palaeontologia Polonica.
  7. (1822). "Histoire naturelle des crustacés fossiles". L.-T. Cellot.
  8. (1956). "Proposed use of the Plenary Powers to suppress the generic name ''Asaphus'' as published by Brongniart in Desmarest, 1817, and to designate a type species in harmony with general usage for the genus ''Asaphus'' Brongniart, 1822 (Class Trilobita)". The Bulletin of Zoological Nomenclature.
  9. (1821). "Petrificata telluris svecanae". Nova Acta Regiae Societatis Scientiarum Upsaliensis.

::callout[type=info title="Wikipedia Source"] This article was imported from Wikipedia and is available under the Creative Commons Attribution-ShareAlike 4.0 License. Content has been adapted to SurfDoc format. Original contributors can be found on the article history page. ::

asaphida-generaordovician-trilobites-of-europefossils-of-estoniafossils-of-russiafossils-of-swedenearly-ordovician-first-appearancesmiddle-ordovician-extinctionstaxa-named-by-alexandre-brongniartfloiandapingiandarriwilianfossil-taxa-described-in-1822asaphidae