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Sceptaspis lincolnensis
Price: $600

Sceptaspis lincolnensis

Trilobite: length – 27.72 mm (1.09”)

        Width – 14.90 mm (0.58”)

Matrix: length – 64.30 mm (2.53”)

      Width - 64.30 mm (2.53”)

Mifflin Member, Platteville Formation

Grant County, Wisconsin

This unique Pterygometopid is so rarely found complete and inflated that even a proper description went uncompleted for almost 75 years. This is a prone example that shows off its elongated genal spines, pinched tail and schizochroal eyes. The right side of the cephalon is slightly compressed that affects the eye on that side (see photos) and the tail has been slightly pushed forward under the posterior thoracic segments. Nevertheless, this is one of the finer examples of this unique genus that most will ever see.

Sceptaspis lincolnensis

The genus Sceptaspis was first recognized as a unique Pterygometopid from the Pre-Chatfieldian Plattin limestone of Missouri and described by Edwin B. Branson in 1909. The genus Sceptaspis is one of the few genera that survived the extinction event at the Chatfieldian boundary in the UMV. Its range is from the Blackriverian up into the Shermanian and whether the same species extends over that interval is uncertain, today only S. lincolnensis is recognized. The trilobite has been collected from the Plattin Formation, Missouri; Platteville Formation, UMV; Bobcaygeon Formation, Ontario; lower Whittaker Formation, Northwest Territories; Decorah Formation, UMV; Verulam Formation, Ontario and Cobourg Formation, Ontario. Sceptaspis lincolnensis is not a common trilobite in any of these formations and rarely encountered complete.

Rolf Ludvigsen and Brian Chatterton wrote a comprehensive assessment of the North American Pterygometopidae in 1982 that still serves as the “go-to” reference. Sceptaspis lincolnensis is characterized by elongated genal spines, a sharply subtriangular pygidium that often has a pinched appearance that exhibits 18-23 distinct axial rings. The cephalon is characteristic of the Pterygometopids exhibiting an inflated, rapidly expanding glabella.

Sceptaspis lincolnensis Trilobite: length – 27.72 mm (1.09”) Width – 14.90 mm (0.58”) Matrix: length – 64.30 mm (2.53”) Width - 64.30 mm (2.53”) Mifflin Member, Platteville Formation Grant County, Wisconsin


This unique Pterygometopid is so rarely found complete and inflated that even a proper description went uncompleted for almost 75 years. This is a prone example that shows off its elongated genal spines, pinched tail and schizochroal eyes. The right side of the cephalon is slightly compressed that affects the eye on that side (see photos) and the tail has been slightly pushed forward under the posterior thoracic segments. Nevertheless, this is one of the finer examples of this unique genus that most will ever see.