Dolichopterus

Dolichopterus Temporal range: Late Silurian PreЄ Є O S D C P T J K Pg N
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Subphylum:	Chelicerata
Order:	†Eurypterida
Superfamily:	†Eurypteroidea
Family:	†Dolichopteridae
Genus:	†Dolichopterus Hall, 1859
Diversity
4–5 species

Dolichopterus is a genus of the prehistoric sea scorpions, arthropods in the order Eurypterida.

Distribution

It lived in the Late Silurian (around 420 million years ago) in shelf or epicontinental seas of the region where Avalonia, Baltica and Laurentia met during the Caledonian orogeny; its fossils have been found in modern-day North America and the Baltic region. They were about 25–30 centimetres (10–12 in) long.

Relatives

Strobilopterus probably was one of the closest relatives of Dolichopterus, but overall the phylogeny and systematics of the family Dolichopteridae is disputed: some place it closer to the Eurypteridae, while others assign it to the second lineage of sea scorpions which contains the Stylonuridae.

Description

Dolichopteridae, which lived in the Silurian and Devonian periods, had outer surfaces that were either smooth with pustules and semilunar scales. Their compound eyes were arcuate and located anteriorly on the prosoma (head). Their abdomens had epimers (lateral projections). The telson, (tail) was lanceolate. Their chelicerae were small, and the first three pairs of walking lags were stout, with powerful spines. The last pair of walking lags had supplementary lobes, while the swimming lags had the last joint enlarged, as part of the paddle. The male genital appendage was long.^[1]

Dolichopterus is distinguishable by its nearly smooth outer surface; its subquadrate prosoma (head), and the slightly serrated margins on the distal joints and lobes of the swimming legs.^[1]

Species

The following species have been named:

• Dolichopterus gotlandicus Kjellesvig-Waering, 1979 – Sweden
• Dolichopterus jewetti Caster & Kjellesvig-Waering, 1956 – USA
• Dolichopterus macrocheirus Hall, 1859 (type species) – USA, Canada
• Dolichopterus siluriceps Clarke & Ruedemann, 1912 – USA, Canada
•  ?Dolichopterus stoermeri Caster & Kjellesvig-Waering, 1956 – Estonia

References

1. ^ ^{a b} L. Størmer (1955). "Merostomata". Treatise on Invertebrate Paleontology, Part P Arthropoda 2, Chelicerata. p. 39. ISBN 08137 30163. 

See also

• List of eurypterids