page_title: Dactylioceras
section_title: Species
hierarchical_section_title: Dactylioceras / Species
caption_attribution_description: English: Exhibit in the National Museum of Nature and Science, Tokyo, Japan. Photography was permitted in the museum without restriction.
context_page_description: Dactylioceras was a widespread genus of ammonites from the Lower Jurassic period, approximately 180 million years ago.
context_section_description: Species within the genus Dactylioceras include:
  D. aequistriatum Zieten, 1830
  D. alpestre Wiedenmayer, 1980
  D. amplum Dagis, 1968
  D. andaluciensis Jiménes & Rivas, 1991
  D. anguiforme Buckman, 1928
  D. anguinum Reinecke, 1818
  D. annuliferum Simpson, 1855
  D. arcus Buckman, 1926
  D. athleticum Simpson, 1855
  D. attenuatum Simpson, 1855
  D. chilense  Hillebrandt and Schmidt-Effing, 1981
  D. commune Sowerby, 1815
  D. comptum Dagis, 1968
  D. consimile Buckman, 1926
  D. crassescens Simpson, 1855
  D. crassifactum Simpson, 1855
  D. crassiusculosum Buckman, 1912
  D. crassiusculum Simpson, 1855
  D. crassulum Buckman, 1921
  D. crosbeyi Simpson, 1843
  D. directum Buckman, 1926
  D. ernsti Lehmann, 1968
  D. gracile Simpson, 1843
  D. helianthoides Yokoyama, 1904
  D. hispansum Schmidt-Effing, 1972
  D. hoelderi Hillebrandt & Schmidt-Effing, 1981
  D. holandrei d'Orbigny, 1845
  D. kanense McLearn, 1930
  D. ketevanae Repin, 2000
  D. laticostatum Bardin et al., 2014
  D. marioni Lissajous, 1906
  D. mirabile Fucini, 1935
  D. mite Buckman, 1927 
  D. peloritanum Fucini, 1935
  D. percostatum Fucini, 1935
  D. perplicatum Fucini, 1935
  D. polymorphum Fucini, 1935
  D. praepositum Buckman, 1927
  D. pseudocommune Fucini, 1935
  D. pseudocrassoides Maubeuge, 1957
  D. semiannulatum Howarth, 1978
  D. semicelatum Simpson, 1843
  D. simplex Fucini, 1935
  D. stresherense Sapunov, 1963
  D. subholandrei Fucini, 1935
  D. suntarense Krimholz, 1957
  D. tardosensis Kovács, 2014
  D. tauromenense Fucini, 1935
  D. temperatum Buckman, 1927
  D. tenuicostatum Young & Bird, 1822
  D. toxophorum Buckman, 1926
  D. triangulum Fischer, 1966
  Dactylioceras commune has shells reaching a diameter of 9–11 centimetres (3.5–4.3 in). Usually the average diameter reach about 24.1 millimetres (0.95 in), while the average width is 8.20 millimetres (0.323 in).
  In these small but strong shells ribs run straight or are slightly convex across the venter. These ribs are quite coarse on the outer whorls and finer on the inner whorls. The whorl section is as round as a circle.
  Fossils of this species have been found in Lower Jurassic, Toarcian age of Canada, France, Italy, Russia, Serbia and Montenegro, United Kingdom and United States.
caption: Dactylioceras (Orthodactylites) helianthoides
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