Salteropterus

Salteropterus Temporal range: Late Silurian, 421–419 Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓
Illustration of the specimen BGS GSM Zf-2864 of S. abbreviatus, which preserves the telson and the tenth to twelfth abdominal segments.
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Arthropoda
Subphylum:	Chelicerata
Order:	†Eurypterida
Superfamily:	†Pterygotioidea
Family:	†Slimonidae
Genus:	†Salteropterus Kjellesvig-Waering, 1951[1]
Type species
†Salteropterus abbreviatus Salter, 1859[2]
Species
†S. abbreviatus Salter, 1859[2] †?S. longilabium Kjellesvig-Waering, 1961[3]

Salteropterus is a genus of eurypterid, an extinct group of aquatic arthropods. Fossils of Salteropterus have been discovered in deposits of Late Silurian age in Britain. Classified as part of the family Slimonidae, the genus contains one known valid species, S. abbreviatus, which is known from fossils discovered in Herefordshire, England, and a dubious species, S. longilabium, with fossils discovered in Leintwardine, also in Herefordshire. The generic name honours John William Salter, who originally described S. abbreviatus as a species of Eurypterus in 1859.

Salteropterus is assumed to have been quite similar to its close relative Slimonia, but the fragmentary nature of the fossil remains of Salteropterus make direct comparisons difficult. Salteropterus does however preserve a highly distinctive telson (the posteriormost division of the body) unlike any other in the Eurypterida. Beginning with an expanded and flattened section, like that of Slimonia, the telson ends in a long stem that culminates in a tri-lobed structure at its end. Though the exact function remains unknown, this structure might have been used for additional balancing alongside the flattened part preceding it.