Mixopterus

Mixopterus; Temporal range: Late Silurian, 426.2–416 Ma PreꞒ Ꞓ O S D C P T J K Pg N
	Fossil of M. kiaeri
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Arthropoda
Subphylum:	Chelicerata
Order:	†Eurypterida
Superfamily:	†Carcinosomatoidea
Family:	†Mixopteridae
Genus:	†Mixopterus; Ruedemann, 1921
Type species
	Mixopterus multispinosus; Ruedemann, 1921
Other species
	M. kiaeri (Størmer, 1934); M. simonsoni (Schmidt, 1883);

Mixopterus is a genus of a eurypterid. It belongs to the family Mixopteridae.

Description

Mixopterus was characterised by a robust exoskeleton with scattered tubercles or semicircular scales. The prosoma (head) was subquadrate, protruding antemedially. The chelicerae (claws in front of the mouth) were small. The first two pairs of walking legs were strongly developed, with long paired spines.^[1] The third and fourth walking legs were moderately sized, with short spines. The preabdomen, the front portion of the body, was narrow with axial furrows, while the postabdomen was narrow. The telson was a curved spine.^[2]

Species

Mixopterus contains three valid species, with some others that historically have been assigned to it being recovered as outside of the genus. The species currently seen as valid species of the genus are:

Mixopterus kiaeri Størmer, 1934 - Ringerike, Norway (Silurian)
Mixopterus multispinosus Clarke & Ruedemann, 1912 - New York (Silurian)
Mixopterus simonsoni Schmidt, 1883 - Saaremaa, Estonia (Silurian)

Invalid or reassigned species are listed below:

Mixopterus dolichoschelus Peach and Hone, 1899 - Lanarkshire and Ayrshire, Scotland (Silurian), reclassified as its own genus, Lanarkopterus.^[3]