Ramphoprionidae

Reconstructed jaw apparatus of Ramphoprion elongatus, from Eriksson (2002).

Belongs within: Eunicida.

The Ramphoprionidae are a group of annelid worms known from the Ordovician and Silurian periods from their fossilised jaws only.

Characters (from Eriksson 2002): Maxillary apparatus asymmetrical; one pair of dorsally flattened, subrectangular carriers present posteriorly, followed by one pair of strongly asymmetrical first maxillae with denticulated dorsal side and slightly enclosed myocoele; short, subrectangular or subtrapezoid basal plate fitted into bight of right first maxilla; left first maxilla and basal plate both with wide transverse posterior margin; anterior maxillae (MII to MIV known) somewhat sickle-shaped with rounded anterior margin; lateral teeth present; laeobasal plate and intercalary tooth absent.

Ramphoprionidae
|--Megaramphoprion Eriksson 2001E02
| `--M. magnusE02
|--Pararamphoprion Männil & Zaslavskaya 1985E02
| |--P. matusevichi Männil & Zaslavskaya 1985E02
| `--P. nordicus Männil & Zaslavskaya 1985E02
|--Ramphoprion Kielan-Jaworowska 1962E02
| |--R. elongatus Kielan-Jaworowska 1966W93
| |--R. gotlandensisE02
| `--R. urbaneki Kielan-Jaworowska 1966W93
`--Protarabellites Stauffer 1933E02
|--*P. humilis Stauffer 1933H62
|--P. rectangularisE02
|--P. staufferiE02
`--P. triangularisE02

*Type species of generic name indicated

References

[E02] Eriksson, M. 2002. The palaeobiogeography of Silurian ramphoprionid polychaete annelids. Palaeontology 45 (5): 985–996.

[H62] Howell, B. F. 1962. Worms. In: Moore, R. C. (ed.) Treatise on Invertebrate Paleontology pt W. Miscellanea: Conodonts, Conoidal Shells of Uncertain Affinities, Worms, Trace Fossils and Problematica pp. W144–W177. Geological Society of America, and University of Kansas Press.

[W93] Wills, M. A. 1993. Annelida. In: Benton, M. J. (ed.) The Fossil Record 2 pp. 271–278. Chapman & Hall: London.

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