Unipeltoceras is an extinct ammonite

Ammonitida

The Ammonitida is an order of more highly evolved ammonoid cephalopods from the Jurassic and Cretaceous time periods, commonly with intricate ammonitic sutures....

 genus included in the perisphictacian

Perisphinctaceae

Perisphinctoidea, formerly Perisphinctaceae, is a superfamily of Middle Jurassic to Lower Cretaceous ammonites, commonly with evolute shells with strong ribbing that typically divides about mid flank before crossing the venter....

 family, Aspidoceratidae

Aspidoceratidae

The Aspidoceratidae comprise a family of middle and upper Jurassic ammonites that make up part of the superfamily Perisphinctaceae, characterized by evolute shells, commonly stocky, that tend to develop tubercles....

, and a member of the subfamily Peltoceratinae

Peltoceratinae

The Peltoceratinae comprise a subfamily in the Aspidoceratidae, .Genera in the Peltoceratinae have sharply ribbed inner whorls and outer whorls that bear spines or tubercles, or have coarse simple ribs...

, that lived during the Callovian

Callovian

In the geologic timescale, the Callovian is an age or stage in the Middle Jurassic, lasting between 164.7 ± 4.0 Ma and 161.2 ± 4.0 Ma. It is the last stage of the Middle Jurassic, following the Bathonian and preceding the Oxfordian....

 stage, late in the Middle Jurassic.

Unipeltoceras is characterized by its strongly evolute, discoidal shell with sharp ribbing on the inner whorls and differing from Peltoceras

Peltoceras

Peltoceras is an extinct ammonite genus from the aspidoceratid subfamily Peltoceratinae that lived during the later part of the Middle Jurassic ....

, s.s. by having only an outer row of tubercles on the outer whorls.

References

• Arkell, et al, 1957. Mesozoic Ammonoidea. Treatise on Invertebrate Paleontology, Part L (Ammonoidea). Geol Soc of America and Univ Kansas Press. p. L336