''Strobilopterus'' is a genus of prehistoric eurypterid of the family

Strobilopteridae Strobilopteridae is an extinct family of eurypterids that lived in the Silurian and Devonian periods. The family is one of three families contained in the superfamily Eurypteroidea (along with Dolichopteridae and Eurypteridae), which in turn is ...

. The genus contains four species, two from the

Devonian The Devonian ( ) is a geologic period and system of the Paleozoic era, spanning 60.3 million years from the end of the Silurian, million years ago (Mya), to the beginning of the Carboniferous, Mya. It is named after Devon, England, whe ...

of Wyoming, United States (''S. princetonii'' and ''S. proteus''), one from the Devonian of Ohio, United States (''S. richardsoni'') and one from the

Silurian The Silurian ( ) is a geologic period and system spanning 24.6 million years from the end of the Ordovician Period, at million years ago ( Mya), to the beginning of the Devonian Period, Mya. The Silurian is the shortest period of the Paleozo ...

of Estonia (''S. laticeps'').Dunlop, J. A., Penney, D. & Jekel, D. 2015. A summary list of fossil spiders and their relatives. In World Spider Catalog. Natural History Museum Bern, online at http://wsc.nmbe.ch, version 16.0 http://www.wsc.nmbe.ch/resources/fossils/Fossils16.0.pdf (PDF).

Description

Strobilopterus proteus subadult and adult

''Strobilopterus'' was a large strobilopterid eurypterid, with adults of the species ''S. proteus'' measuring approximately 15 to 20 centimetres in length. The

carapace A carapace is a Dorsum (biology), dorsal (upper) section of the exoskeleton or shell in a number of animal groups, including arthropods, such as crustaceans and arachnids, as well as vertebrates, such as turtles and tortoises. In turtles and tor ...

of ''Strobilopterus'' was wide and semicircular in shape, with the lateral eyes lunate to crescentic with the palpebral lobe between the central and centrimesial sectors. The first pair of appendages were small, lacking denticles, and the subsequent four pairs of appendages were likewise also small, but with fixed spines and serrated distal

podomere The arthropod leg is a form of jointed appendage of arthropods, usually used for walking. Many of the terms used for arthropod leg segments (called podomeres) are of Latin origin, and may be confused with terms for bones: ''coxa'' (meaning hip, pl ...

margins. The sixth and last pair of appendages were short but were powerfully serrated on the anterior margins of the podomeres. The type A genital appendage was long and undivided, the type B appendage was more oval in shape.

References

Eurypteroidea Devonian eurypterids Fossils of the United States Eurypterids of North America Silurian eurypterids Eurypterids of Europe {{Eurypterid-stub