Sceptrites is an orthoceratoid

Orthoceratoidea

The Orthoceratoidea is a superorder , sometimes considered an infraclass or even a subclass, that comprizes nautiloid orders that have orthoconic to slightly cyrtoconic shells and central to subcentral siphuncles in which there may be internal deposits...

 genus contained within the pseudorthocerid family Spyroceratidae

Spyroceratidae

Spyroceratidae are defined as Pseudorthocerida with uniformly slender siphuncle segments, longer than wide, that contract sharply near either end, in which endosiphuncular deposits first form a compete annulus before fusing ventrally....

 known by its slightly compressed, possibly endogastrically curved, cyrtoconic shell. Sceptrites has been found in Devonian

Devonian

The Devonian is a geologic period and system of the Paleozoic Era spanning from the end of the Silurian Period, about 416.0 ± 2.8 Mya , to the beginning of the Carboniferous Period, about 359.2 ± 2.5 Mya...

 sediments in Ohio and N.Y. in the United States and in Victoria, Australia.

The Sceptrites shell is moderately narrow and expands slightly with an even, gentle curvature. Early sutures of straight transverse, later ones have slight lateral lobes. The siphuncle

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 Spirula...

is subcentral. Mural cameral deposits are deposited along the concave side of the shell—reason to assume its endogastric nature.

External links

Sceptrites The Paleobiology Database