Dolichopteridae are an extinct family of eurypterid

Eurypterid

Eurypterids are an extinct group of arthropods related to arachnids which include the largest known arthropods that ever lived. They are members of the extinct order Eurypterida ; which is the most diverse Paleozoic chelicerate order in terms of species...

s that lived in the Silurian

Silurian

The Silurian is a geologic period and system that extends from the end of the Ordovician Period, about 443.7 ± 1.5 Mya , to the beginning of the Devonian Period, about 416.0 ± 2.8 Mya . As with other geologic periods, the rock beds that define the period's start and end are well identified, but the...

 and Devonian

Devonian

The Devonian is a geologic period and system of the Paleozoic Era spanning from the end of the Silurian Period, about 416.0 ± 2.8 Mya , to the beginning of the Carboniferous Period, about 359.2 ± 2.5 Mya...

 periods.

Description

Dolichopteridae had outer surfaces that were either smooth or 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.

Genera

• Class Merostomata
  Merostomata
  Merostomata is the name given to a grouping of the extinct Eurypterida and the Xiphosura . The term was originally used by James Dwight Dana to refer to Xiphosura only, but was emended by Henry Woodward to cover both groups....
  
   Dana, 1852
• Order Eurypterida Burmeister, 1843
• Suborder Eurypterina Burmeister, 1843
• Superfamily Eurypteroidea
  Eurypteroidea
  Eurypteroidea are an extinct superfamily of eurypterids.-Description:Eurypteroidea, which lived from the Ordovician to Permian periods, were characterized by their last pair of prosomal appendages, which were developed as swimming legs, carrying paddles formed by the expansion of the two...
  
   Burmeister, 1843

  Family Dolichopteridae Kjellesvig-Waering & Størmer, 1952

  Genus Dolichopterus

  Dolichopterus

  Dolichopterus is a genus of the prehistoric sea scorpions, arthropods in the order Eurypterida.-Distribution:It lived in the Late Silurian in shelf or epicontinental seas of the region where Avalonia, Baltica and Laurentia met during the Caledonian orogeny; its fossils have been found in...

  
  Hall, 1859

  Genus Rudemannipterus Kjellesvig-Waering, 1966

  Genus Buffalopterus Kjellesvig-Waering & Heubusch, 1962

  Genus Strobilopterus

  Strobilopterus

  Strobilopterus is a genus of prehistoric eurypterid of the family Dolichopteridae.-Description:Dolichopterids, which lived in the Silurian and Devonian periods, were medium-sized, and had outer surfaces that were either smooth with pustules and semilunar scales. Their compound eyes were arcuate...

  
  Ruedemann, 1955

  Genus Syntomopterus Kjellesvig-Waering, 1961