One of the two most common Eurypterus fossils found. It is very similar to E. remipes and often found in the same localities, but the eyes are placed at a more posterior position on the carapace of E. lacustris. It is also slightly larger with a slightly narrower metastoma. Its status as a distinct species was once disputed before diagnostic analysis by Tollerton in 1993. Its specific name means 'from a lake', from Latin ('lake'). Found in New York and Ontario. Eurypterus leopoldi Tetlie, 2006 – Silurian, Canada Frontmost tergite is reduced. Metasoma is rhombiovate in shape with tooth-like projections at the anterior part. The pretelson has serrated edges. the epimera are large, semi-angular with angular striations. The telson is styliform with large angular striations interspersed among smaller more numerous striations. The species is named after Port Leopold and the Leopold Formation where they were collected. Found in the Leopold Formation of Somerset Island, Canada. Eurypterus megalops Clarke & Ruedemann, 1912 – Silurian, USA Specific name means "large eye", from Greek ( 'big or large') and ( 'eye'). Discovered in New York, United States. ?Eurypterus minor Laurie, 1899 – Silurian, Scotland Small Eurypterus with large pustules on the carapace and abdomen. Does not possess the scale ornamentation found in other species of Eurypterus. It is the earliest known species of Eurypterus. They have large palpebral lobes (part of "cheeks" of the carapace adjacent to the compound eyes), making it easy to mistake their eyes for being oval. This enlargement is more typical of the genus Dolichopterus and it may actually belong to Dolichopteridae. The specific name means 'smaller', from Latin . Found in the Reservoir Formation of Pentland Hills, Scotland. Eurypterus ornatus Leutze, 1958 – Silurian, USA Ornamentation of pustules on the entire surface of the carapace and at least the first tergite. Does not possess raised scales. Its specific name means 'adorned', from Latin ('adorned, ornate'). Recovered from Fayette, Ohio. Eurypterus pittsfordensis Sarle, 1903 – Silurian, USA The posterior margin of the carapace has three raised scales. Appendages II to IV has two spines per podomere. The metastoma is rhomboid in shape with a deep notch at the front part. The postabdomen has serrated fringes at the middle with small angular epimera at the sides. The pretelson has large, semiangular epimera with angular striations at the margins. The telson is styliform with sparse angular striations at the margins. The