''Campendoceras'' is a genus of proterocameroceratids from the

Lower Ordovician The Early Ordovician is the first epoch of the Ordovician period, corresponding to the Lower Ordovician series of the Ordovician system. It began after the Age 10 of the Furongian epoch of the Cambrian and lasted from to million years ago, unt ...

of NW

Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...

and possibly

Estonia Estonia, officially the Republic of Estonia, is a country in Northern Europe. It is bordered to the north by the Gulf of Finland across from Finland, to the west by the Baltic Sea across from Sweden, to the south by Latvia, and to the east by Ru ...

that can be recognized by its slender, weakly endogastric, longiconic and annulate shell and large marginal

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

that contains endocones. The curvature in ''Campendoceras'' is less distinct than that in ''

Clitendoceras ''Clitendoceras'' is a genus of cephalopods in the order Endocerida from the Lower Ordovician (m-u Canadian) with an elongate shell with a slight downward, endogastric, curvature and a siphuncle that lies along the ventral margin. Common for end ...

'' or ''

Mcqueenoceras ''Mcqueenoceras'' is an extinct genus of early endocerid, a nautiloid from the Floian epoch of the late early Ordovician period. It was similar in overall form to ''Clitendoceras'', from which it may have been derived. ''Mcqueenoceras'', like ''C ...

'' and the siphuncle is larger.

References

* Teichert, C, 1964. Proterocameroceratidae, pp 166– 170 in the

Treatise on Invertebrate Paleontology The ''Treatise on Invertebrate Paleontology,'' published from 1953–2007 by the Geological Society of America and the University of Kansas, then 2009–present by the University of Kansas Paleontological Institute, is a definitive multi-authore ...

Part K. Geol Soc of America and Univ of Kansas Press. {{Taxonbar, from=Q5028259 Prehistoric nautiloid genera Ordovician cephalopods Prehistoric invertebrates of Oceania Molluscs of Oceania Fossil taxa described in 1954 Proterocameroceratidae