Aipoceratidae

Aipoceras pinhookense. Figure from Kummel (1964).

Belongs within: Nautilida.

The Aipoceratidae were a family of nautilid cephalopods that lived during the Carboniferous. Of the genera assigned to this family in Kummel (1964), Aipoceras was loosely coiled and somewhat hook-shaped, while Asymptoceras was more tightly coiled with only the distal end of the body chamber not in contact with the proceeding coil.

Characteristics (from Kummel 1964): Loosely coiled or whorls faintly impressed; shell surface smooth; mature aperture modified (expanded and angular in shape).

<==Aipoceratidae
    |--Asymptoceras Ryckholt 1852 H99 [incl. Oncodoceras Hyatt 1893 K64]
    |    |--*A. cyclostomum (Phillips 1836) [=Nautilus cyclostomus] H99
    |    |--A. crassilabrum Foord 1900 H99
    |    |--A. foordi Hyatt 1893 H99
    |    |--A. fusiforme Hyatt 1884 H99
    |    |--A. newloni Hyatt 1891 P68
    |    `--A. pyxis Shimansky 1967 H99
    `--Aipoceras Hyatt 1884 H99
         |--*A. gibberosum (de Koninck 1880) [=Gyroceras gibberosum] H99
         |--A. compressum (Foord 1891) [=Gyroceras (Aipoceras) compressum] H99
         |--A. easleyense Miller & Furnish 1938 H99
         |--A. hainesianum Foord 1901 H99
         |--A. micklense Turner 1954 H99
         |--A. oweni Miller & Furnish 1938 H99
         `--A. pinhookense Miller & Furnish 1938 H99

*Type species of generic name indicated

REFERENCES

[H99] Histon, K. 1999. A revision of A. H. Foord’s monograph of Irish Carboniferous nautiloid cephalopods (1897-1901). Part 2. Monograph of the Palaeontographical Society 153: 63-129.

[K64] Kummel, B. 1964. Nautiloidea – Nautilida. In Treatise on Invertebrate Paleontology pt. K. Mollusca 3. Cephalopoda – General Features – Endoceratoidea – Actinoceratoidea – Nautiloidea – Bactritoidea (R. C. Moore, ed.) pp. K383-K457. The Geological Society of America and the University of Kansas Press.

[P68] Purnell, L. R. 1968. Catalog of the Type Specimens of Invertebrate Fossils. Part I: Paleozoic Cephalopoda. United States National Museum Bulletin 262: 1-198.