Allocotoceras is an endocerid from the Lower Ordovician (upper Canadian) Karmberg Formation of Australia (Tasmania),[1] included in the Endoceratidae, based on small, straight or gently curved siphuncles.

Septal necks, according to Teichert, 1964, are holochoanitic, reaching to the previous septum.

Endocones are described as having a dorsal wedge, or process, making the internal opening, or endosiphocone, semicircular in cross section.

In this sense Allocotoceras seems to resemble the genus Najaceras.