Order Nautilida Agassiz 1847
Family Solenochilidae Hyatt 1883
Genus Solenochilus Meek and Worthen 1870

While Meek & Worthen named Solenochilus in 1870, D’Orbigny (1850) had previously referred to these cephalopods as Nautilus (Cryptoceras). Meek & Worthen proposed a name change because Cryptoceras was given to a different group of cephalopods by Dr. Barrande in 1846. The situation goes deeper because Latreille (1804) used Cryptoceras as a Hymenoptera (flying insect) genus. There is more, but to make a long story short, Nautilus (Solenochilus) became the name for this coiled, large, winged, and rapidly expanding cephalopod genus.

Solenochilus sp. from the Brush Creek limestone at SL 6533.
Fig. 1.—Solenochilus sp. from the Brush Creek limestone at SL 6533. A venter view of the body chamber that is primarily a steinkern. The boulder containing this specimen was part of a fire pit ring. Melted plastic adheres to the wide end of the body chamber. Scale bar = 1 cm.
Solenochilus sp. from the Brush Creek limestone at SL 6533.
Fig. 2.—Solenochilus sp. from the Brush Creek limestone at SL 6533. A, venter view of body chamber that is primarily a steinkern, the shell difficult to retain when prepping from this limestone; B, venter view centered over phragmocone boundary with visible marginal siphuncle; C, three-quarters view, CG-0100. Scale bar = 5 cm.
Fig. 3.—Solenochilus sp. and partner Metacoceras sp. (above) from the Brush Creek limestone at SL 6533. This large assemblage also included the mold of a trilobite tail and the tooth of Petalodus ohioensis, CG-0056. Scale bar = 2 cm.

References

Late Carboniferous Fossils from the Glenshaw Formation in Armstrong County, Pennsylvania

Localities: Locality SL 6445 | Locality SL 6533

Trilobita | Crinoidea

Bivalvia: Allopinna | Parallelodon | Septimyalina

Cephalopoda: Metacoceras | Poterioceras | Pseudorthoceras | Solenochilus

Gastropoda: Amphiscapha | Bellerophon | Cymatospira | Euphemites | Glabrocingulum | Meekospira | Orthonychia | Patellilabia | Pharkidonotus | Retispira | Shansiella | Strobeus | Trepospira | Worthenia

Brachiopoda: Cancrinella | Composita | Isogramma | Linoproductus | Neospirifer | Parajuresania | Pulchratia

Chordata: Petalodus | Glikmanius