Stroboceras is an extinct nautiloid named by Hyatt in 1884 that's included in the nautilid

Nautilida

The Nautilida constitute a large and diverse order of generally coiled nautiloid cephalopods that began in the mid Paleozoic and continues to the present with a single family, the Nautilidae which includes two genera, Nautilus and Allonautilus, with six species...

 family Trigonoceratidae

Trigonoceratidae

The Trigonoceratidae is a family of coiled nautiloid cephalopods that lived during the period from the Early Carboniferous to the Early Permian.-Diagnosis:...

; the group that have rise to the Nautilidae which includes the living Nautilus

Nautilus

Nautilus is the common name of marine creatures of cephalopod family Nautilidae, the sole extant family of the superfamily Nautilaceae and of its smaller but near equal suborder, Nautilina. It comprises six living species in two genera, the type of which is the genus Nautilus...

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Stroboceras is characterized by a loosely coiled evolute shell bearing prominent longitudinal ridges and grooves; with a variable cross section, generally higher than wide, flanks convergent on the venter, and a subcentral siphuncle.