Abbasites

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Abbasites
Temporal range: early Middle Jurassic
Scientific classification e
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Subclass: Ammonoidea
Order: Ammonitida
Family: Erycitidae
Subfamily: Erycitinae
Genus: Abbasites
Buckman, 1921
Species
  • see text

Abbasites is an extinct genus of ammonites from the early Middle Jurassic included in the ammonitid family Erycitidae.

Description[edit]

Abbasites is small and subglobular with ribbing that divides high on its sides and which has an interruption on the venter that replaces the keel, generally characteristic of the Hammatoceratidae [1]

Classification[edit]

Abbasites was originally described by Sydney S. Buckman in 1921,[1][2] with A. abbas as its type species, and was considered by some to be a subgenus of Erycites. Abbasites was included in the Otoitidae, the ancestral family of the Stephanocerataceae, according to Westermann (1965)[3][4] and Imlay (1984)[3] but was previously placed in the Hildoceratacean family Hammatoceratidae by Arkell et al. (1957).[1] It is currently regarded as a full genus in the Erycitidae subfamily Erycitinae.[5][6] The genus Erycites is believed to be ancestral to Abbasites. However, Abbasites is believed to have left its own descendants in the ammonite family Otoitidae.[7]

Valid species:

  • Abbasites abbas, found in southern Spain.
  • A. platystomus, found in southern Alaska.
  • A. sparsicostatus (described by Ralph Imlay)

Dubious and excluded species:

  •  ?Abbasites cestiferus; type specimen too small to be certain about classification.
  • (Abbasites) challinori;[8] originally thought to be closely related to A. abbas, but following subsequent study has been removed from Abbasites to the genus Opuatia[8]

References[edit]

  1. ^ a b c Arkell,Kummel, and Wright 1957. Mesozoic Ammonoidea, Treatise on Invertebrate Paleontology, Part L, Mollusca 4
  2. ^ Abbasites in Nomenclator Zoologicus
  3. ^ a b Imlay, Ralph W . 1984. Early and Middle Bajocian (Middle Jurassic) Ammonites from Southern Alaska; U.S.G.S PP 1322 [1]
  4. ^ Westernamm,G. E. G. 1965.Septal and Sutural Patterns in Evolution and Taxonomy of Thamboceratidae and Clydoniceratidae (M Jurassic Ammonitina).Journal of Paleontology 39(5)864-874, Sept
  5. ^ Kovács, Z.; Géczy, B. (2008). "Upper Toarcian – Middle Aalenian (Jurassic) Erycitinae SPATH (Ammonitina) from the Gerecse Mts, Hungary" (PDF). 125th Anniversary of the Department of Palaeontology at Budapest University – A Jubilee Volume Hantkeniana. 6: 57–108. 
  6. ^ Dietze, V.; et al. (2010). "Rare Middle Jurassic ammonites of the families Erycitidae, Otoitidae and Stephanoceratidae from southern Germany" (PDF). Zitteliana. 50: 71–88. 
  7. ^ Parsons C. F.2008 A Systematic Revision of the Bajocian Ammonite Subfamily Sphaeroceratinae, pages 1–90 Unpublished thesis.
  8. ^ a b Westernamm et al. Bajocian (Middle Jurassic) Ammonitina of New Zealand. New Zealand Journal of Geology and Geophysics, vol43, issue 1 pp 33–57; The Royal Society of New Zealand

External links[edit]