New fossil finds also revealed the presence of Pterygotus in several European countries where it had previously been unknown and established it as a highly taxonomically diverse genus.
P. barrandei was named in 1898 and has fossil representation in Pridoli age deposits of the Czech Republic.
P. barrandei is noted to be very similar to P. cobbi, and a close relation between the two species is assumed.
Despite many similarities, the two species do have some differences, most prominently in the cheliceral teeth of the free rami.
The largest tooth of the free ramus of P. barrandei is significantly longer than the corresponding tooth in P. cobbi and the teeth of the free ramus of P. barrandei are directed forwards more prominently in general.
Fossils of P. barrandei are rare, with fossil finds being confined to a handful of formations of Pridoli age in Bohemia.
Known fossils include some incomplete chelicerae and a metastoma.
Some additional fossil remains have been assigned to the species, consisting of coxae and a genital appendage, but their assignment to the species is doubtful.

The species P. nobilis, described in 1872, is based on a small and fragmentary chelicera found in what today is the Czech Republic.
The arrangement of teeth seen in this claw, though most teeth are not preserved, was noted by researcher Max Semper in 1897 as sharing little to no resemblance with what is seen in the type species of Pterygotus, P. anglicus, and was noted to in fact be more similar to what is seen in P. buffaloensis and P. bohemicus.
Today P. buffaloensis is considered a junior synonym of P. bohemicus, which has been reclassified as part of the closely related genus Acutiramus.
The fragmentary remains of P. nobilis makes further studies of its precise identity difficult, Semper suggested that it may be synonymous with Acutiramus bohemicus, but noted that the "questions [about its identity] can not be answered from the material available to me".

Another species, P. kopaninensis, also named in 1872, is known from a single and incomplete fixed cheliceral ramus (specimen number L1396) recovered from the Kopanina Formation around the village of Zadní Kopanina, located in Prague.
The specimen measures 4.3 cm (1.7 in) in length and was at one point assigned to Erettopterus due to the "peculiar hook-like termination of the ramus", a feature now known to be present due to a remnant of the free ramus being present in the fossil.
The tooth pattern and shape of the claw suggests that an assignment to Pterygotus is more likely.

P. siemiradzkii, described by Embrik Strand in 1926 based on fossil material from western Ukraine, is based on highly fragmentary material with little diagnostic value.
The single specimen designated as P. siemiradzkii, a telson, has unusual and pronounced ridges that are not seen in any known species of Pterygotus, nor in any other genus of pterygotid eurypterids, which makes its assignment to Pterygotus questionable.

In 1964, two species described by Kjellesvig-Waering increased the known range of Pterygotus to Scotland (P. lanarkensis) and Estonia (P. impacatus), both Ludlow in age.
P. lanarkensis was the second pterygotid to be discovered from the well known eurypterid fauna of Lesmahagow in Lanarkshire, Scotland.
As pterygotids commonly occur in association with multiple related genera, it was considered unusual that there was only one species, Erettopterus bilobus, present in Lesmahagow.
Fossil remains of P. lanarkensis had been known since 1868 (first collected by Robert Slimon in 1855-1860), but were first recognized as such by Kjellesvig-Waering in 1964.
Represented by a large chelicera (specimen number 53890 in the British Museum of Natural History) originally doubtfully referred to Erettopterus bilobus, P. lanarkensis more closely resembles P. anglicus than it does species of Erettopterus.
The terminal tooth (broken in this specimen) is 0.9 cm in length and the central tooth is unusually short.
The combination of an unusually long terminal tooth and an underdeveloped central tooth differentiates P. lanarkensis f
New fossil finds also revealed the presence of Pterygotus in several European countries where it had previously been unknown and established it as a highly taxonomically diverse genus. P. barrandei was named in 1898 and has fossil representation in Pridoli age deposits of the Czech Republic. P. barrandei is noted to be very similar to P. cobbi, and a close relation between the two species is assumed. Despite many similarities, the two species do have some differences, most prominently in the cheliceral teeth of the free rami. The largest tooth of the free ramus of P. barrandei is significantly longer than the corresponding tooth in P. cobbi and the teeth of the free ramus of P. barrandei are directed forwards more prominently in general. Fossils of P. barrandei are rare, with fossil finds being confined to a handful of formations of Pridoli age in Bohemia. Known fossils include some incomplete chelicerae and a metastoma. Some additional fossil remains have been assigned to the species, consisting of coxae and a genital appendage, but their assignment to the species is doubtful.
The species P. nobilis, described in 1872, is based on a small and fragmentary chelicera found in what today is the Czech Republic. The arrangement of teeth seen in this claw, though most teeth are not preserved, was noted by researcher Max Semper in 1897 as sharing little to no resemblance with what is seen in the type species of Pterygotus, P. anglicus, and was noted to in fact be more similar to what is seen in P. buffaloensis and P. bohemicus. Today P. buffaloensis is considered a junior synonym of P. bohemicus, which has been reclassified as part of the closely related genus Acutiramus. The fragmentary remains of P. nobilis makes further studies of its precise identity difficult, Semper suggested that it may be synonymous with Acutiramus bohemicus, but noted that the "questions [about its identity] can not be answered from the material available to me".
Another species, P. kopaninensis, also named in 1872, is known from a single and incomplete fixed cheliceral ramus (specimen number L1396) recovered from the Kopanina Formation around the village of Zadní Kopanina, located in Prague. The specimen measures 4.3 cm (1.7 in) in length and was at one point assigned to Erettopterus due to the "peculiar hook-like termination of the ramus", a feature now known to be present due to a remnant of the free ramus being present in the fossil. The tooth pattern and shape of the claw suggests that an assignment to Pterygotus is more likely.
P. siemiradzkii, described by Embrik Strand in 1926 based on fossil material from western Ukraine, is based on highly fragmentary material with little diagnostic value. The single specimen designated as P. siemiradzkii, a telson, has unusual and pronounced ridges that are not seen in any known species of Pterygotus, nor in any other genus of pterygotid eurypterids, which makes its assignment to Pterygotus questionable.
In 1964, two species described by Kjellesvig-Waering increased the known range of Pterygotus to Scotland (P. lanarkensis) and Estonia (P. impacatus), both Ludlow in age. P. lanarkensis was the second pterygotid to be discovered from the well known eurypterid fauna of Lesmahagow in Lanarkshire, Scotland. As pterygotids commonly occur in association with multiple related genera, it was considered unusual that there was only one species, Erettopterus bilobus, present in Lesmahagow. Fossil remains of P. lanarkensis had been known since 1868 (first collected by Robert Slimon in 1855-1860), but were first recognized as such by Kjellesvig-Waering in 1964. Represented by a large chelicera (specimen number 53890 in the British Museum of Natural History) originally doubtfully referred to Erettopterus bilobus, P. lanarkensis more closely resembles P. anglicus than it does species of Erettopterus. The terminal tooth (broken in this specimen) is 0.9 cm in length and the central tooth is unusually short. The combination of an unusually long terminal tooth and an underdeveloped central tooth differentiates P. lanarkensis f
Pterygotus