''Jovellania'' is a genus of extinct prehistoric nautiloids from the order

Oncocerida The Oncocerida comprise a diverse group of generally small nautiloid cephalopods known from the Middle Ordovician to the Mississippian (early Carboniferous; one possible member is known from the Early Permian), in which the connecting rings are t ...

known from the Lower

Devonian The Devonian ( ) is a geologic period and system of the Paleozoic era, spanning 60.3 million years from the end of the Silurian, million years ago (Mya), to the beginning of the Carboniferous, Mya. It is named after Devon, England, whe ...

of Europe (France, Germany).Sweet, W. C. (1964). "Nautiloidea -Oncocerida". '' Treatise on Invertebrate Paleontology''. Part K Nautiloidea, Teichert & Moore (eds) Nautiloids form a broad group of shelled

cephalopods A cephalopod is any member of the molluscan class Cephalopoda (Greek plural , ; "head-feet") such as a squid, octopus, cuttlefish, or nautilus. These exclusively marine animals are characterized by bilateral body symmetry, a prominent head, an ...

that were once diverse and numerous but are now represented by only a handful of species in two genera. ''Jovellania'' was named by Bayle (1879) and is type genus for the

Jovellaniidae Jovellaniidae was established as a family within the Oncocerida to include genera characterized by longiconic orthocones and cyrtocones with a subtriangular to depressed cross-section in which the ventral (siphuncular) side is typically angular o ...

, a family assigned to the Oncocerida by Flower (1950)Flower, R. H & Kummel, B. (September 1950). "A Classification of the Nautiloidea". '' Journal of Paleontology''. 24 (3).

Morphology

''Jovellania'' can be described as having a slowly widening, straight or slightly cytoconic shell with faint undulations and nearly circular or slightly depressed cross-section Kroger, B. (March 2008). "Nautiloids Before and During the Origin of Ammonoids ...". '' Special Papers in Palaeontology''. no.79, The Palaentological Association, London. The ventrolateral sides are flattened causing the prosiphuncular (ventral) side to be slightly angular. Septa are closely spaced and sutures are transverse. The

siphuncle The siphuncle is a strand of tissue passing longitudinally through the shell of a cephalopod mollusk. Only cephalopods with chambered shells have siphuncles, such as the extinct ammonites and belemnites, and the living nautiluses, cuttlefish, and ...

is positioned between the center and the ventral margin and closer to the margin; segments are expanded into the chambers; actinosiphonate deposits consist of longitudinal lamellae

References

* Sepkoski, J. J. Jr. (2002). "A compendium of fossil marine animal genera". Jablonski, D. J. & Foote, M. L. (eds.). ''Bulletins of American Paleontology''. 363: 1–560
Sepkoski's Online Genus Database (Cephalopoda)
{{Taxonbar, from=Q6296734 Prehistoric nautiloid genera Oncocerida