Not to be confused with living tailless whip scorpion genus, Weygoldtia.
Weygoldtina is an extinct genus of tailless whip scorpion known from Carboniferous period, and the only known member of the family Weygoldtinidae.[1] It is known from two species described from North America and England and originally described in the genus Graeophonus,[2] which is now considered a nomen dubium.[1]
Weygoldtina scudderi (USNM 37969), originally described as Graeophonus carbonarius
A single fossil from the Cape Breton Island was interpreted as a fossil dragonfly larva and described by Samuel Hubbard Scudder in 1876 as Libellula carbonaria.[3][4][1] The fossil was very incomplete, consisting of a solitary opisthosoma.[4] With the discovery of more complete fossils from Mazon Creek, Illinois, and Joggins, Nova Scotia, Samuel Scudder redescribed the fossils as amblypygids and moved the species to a new genus, Graeophonus as Graeophonus carbonarius. While describing the British species, Graeophonus anglicus, Reginald Innes Pocock noted significant differences between the Nova Scotian and more complete Mazon Creek fossils.[4] As a result he erected the species Graeophonus scudderi to accommodate the Mazon Creek specimen, and restricted species G. carbonarius to the Canadian specimens. It was later suggested by Reginald Pocock in 1913 that the two species, G. carbonarius and G. scudderi were indeed the same, and this has resulted in confusion over both the name to be used and number of species present in North America.[4]Graeophonus anglicus has been found in the English Middle Coal Measures of Coseley, Staffordshire. Known from ten specimens that are now deposited in the British Museum, the species was named by Reginald Pocock in 1911.[5]
However, in 2018, researchers considered that the genus Graeophonus is invalid, because the holotype specimen of G. carbonarius (=Libellula carbonaria) is poorly preserved and hard to identify as an amblypygid.[1] Even in 1911, Pocock considered that the holotype specimen possibly did not belong to an amplypygid.[5] More confusingly, A.I. Petrunkevitch suggested to use another more complete specimen as the holotype in 1913, even though the original holotype specimen was not lost at that time. To solve problems caused by this, Jason A. Dunlop erected a new genus, Weygoldtina, and placed most specimens of G. carbonarius and G. scudderi into Weygoldtina scudderi, and G. anglicus is renamed as Weygoldtina anglica.[1]
Morphologyedit
Tomographic (left) and illustrated (right) reconstruction of W. anglica
W. scudderi had body length about 17 millimetres (0.67 in).[1]
Body length of W. anglica ranges from 11–13 millimetres (0.43–0.51 in) for complete specimens, and the partly complete 18 millimetres (0.71 in) long specimen shows a distinct pear-shaped ocular tubercle on the carapace.[4] CT data confirmed the presence of lateral eye tubercles.[2] The center of the dorsal shield has a deep depression which probably acted as an attachment site for the muscles of the sucking stomach.[2] Raptorial pedipalps were not mantis-like shaped like most of modern amplypygid but similar to ones of modern genus Paracharon.[2] Main difference of pedipalp compared to Paracharon is the spine orientation. While the pedipalp spines in Paracharon appear to be almost parallel and slightly tilted outwards, W. anglica, however, the angle between the spines appears to be larger, at least 90 degrees. This character suggests that W. anglica used its pedipalps not exactly in the same way as the modern Paracharon.[6] Study in 2021 shows two prominent spines on each pedipalp, which were not recognized before.[6] Although first pairs of legs are not completely preserved, they are probably long and antenna-like, same as modern amblypygids.[2]
Main difference of two species is anterior projection from the prosomal dorsal shield. It is slightly wider, shorter and more diffuse in W. scudderi.[1]
Classificationedit
Photos of the only living paleoamblypygid tailless whip scorpion, Paracharon caecus
The morphology of both the abdomen and pedipalps in Weygoldtina is very similar to the modern genus Paracharon. In 2007, Weygoldtina (Graeophonus at that time) was placed in Paracharontidae, same family as Paracharon. While Paracharon is notably blind, this is thought to be a secondary result of living almost exclusively within termite mounds. Thus the blindness was not considered a reason to exclude Graeophonus from Paracharontidae.[4] However, in 2017, Weygoldtina is rejected from Paracharontidae, and treated as stem-paleoamblypygid. Paleoamblypygi is a monophyletic suborder that contains Paracharon, Weygoldtina, in addition Paracharonopsis cambayensis that is described from Eocene Cambayamber.[2] In 2018, new family Weygoldtinidae is given for Weygoldtina.[1] Differences in morphology of pedipalps and first pair of leg in Paracharon and Weygoldtina may show closer relationship of Paracharon and Euamblypygi, but also this could be a point to an apomorphic condition of Weygoldtina. Researchers claimed that it needs to be considered that Weygoldtina is not as similar to Paracharon as a brief look might suggest, but is characterised by own specialisations.[6]
Referencesedit
^ abcdefghDunlop, Jason A. (2018-03-01). "Systematics of the Coal Measures whip spiders (Arachnida: Amblypygi)". Zoologischer Anzeiger. In honor of Peter Weygoldt. 273: 14–22. doi:10.1016/j.jcz.2017.11.004. ISSN 0044-5231.
^ abcdefGarwood, Russell J.; Dunlop, Jason A.; Knecht, Brian J.; Hegna, Thomas A. (2017). "The phylogeny of fossil whip spiders". BMC Evolutionary Biology. 17 (1): 105. doi:10.1186/s12862-017-0931-1. ISSN 1471-2148. PMC5399839. PMID 28431496.
^Scudder, S.H. (1876). "A century of Orthoptera. Decade VI. Forficulariae (North America)". Proceedings of the Boston Society of Natural History. 18: 257–264.
^ abcdefDunlop, J.A.; Zhou, G.R.S.; Braddy, S.J. (2007). "The affinities of the Carboniferous whip spider Graeophonus anglicus Pocock, 1911 (Arachnida:Amblypygi)". Earth and Environmental Science Transactions of the Royal Society of Edinburgh. 98 (2): 165–178. doi:10.1017/S1755691007006159. S2CID 140582794.
^ abPetrunkevitch, Alexander (1913). A Monograph of the Terrestrial Palaeozoic Arachnida of North America. Yale University Press.
^ abcHaug, Carolin; Haug, Joachim T. (2021-09-01). "The fossil record of whip spiders: the past of Amblypygi". PalZ. 95 (3): 387–412. doi:10.1007/s12542-021-00552-z. ISSN 1867-6812. S2CID 232434849.
Further readingedit
Dunlop, J.A. (1994). An Upper Carboniferous amblypygid from the Writhlington Geological Nature Reserve. Proceedings of the Geologists' Association 105:245-250.
January 01, 1970
weygoldtina, confused, with, living, tailless, whip, scorpion, genus, weygoldtia, extinct, genus, tailless, whip, scorpion, known, from, carboniferous, period, only, known, member, family, weygoldtinidae, known, from, species, described, from, north, america, . Not to be confused with living tailless whip scorpion genus Weygoldtia Weygoldtina is an extinct genus of tailless whip scorpion known from Carboniferous period and the only known member of the family Weygoldtinidae 1 It is known from two species described from North America and England and originally described in the genus Graeophonus 2 which is now considered a nomen dubium 1 WeygoldtinaTemporal range Pennsylvanian Duckmantian Kasimovian PreꞒ Ꞓ O S D C P T J K Pg N Fossil specimen of W anglica Scientific classification Domain Eukaryota Kingdom Animalia Phylum Arthropoda Subphylum Chelicerata Class Arachnida Order Amblypygi Family Weygoldtinidae Genus WeygoldtinaDunlop 2018 Species Weygoldtina anglica Pocock 1911 Weygoldtina scudderi Pocock 1911 Synonyms Graeophonus anglicus Pocock 1911 Graeophonus scudderi Pocock 1911 Contents 1 History 2 Morphology 3 Classification 4 References 5 Further readingHistory edit nbsp Weygoldtina scudderi USNM 37969 originally described as Graeophonus carbonarius A single fossil from the Cape Breton Island was interpreted as a fossil dragonfly larva and described by Samuel Hubbard Scudder in 1876 as Libellula carbonaria 3 4 1 The fossil was very incomplete consisting of a solitary opisthosoma 4 With the discovery of more complete fossils from Mazon Creek Illinois and Joggins Nova Scotia Samuel Scudder redescribed the fossils as amblypygids and moved the species to a new genus Graeophonus as Graeophonus carbonarius While describing the British species Graeophonus anglicus Reginald Innes Pocock noted significant differences between the Nova Scotian and more complete Mazon Creek fossils 4 As a result he erected the species Graeophonus scudderi to accommodate the Mazon Creek specimen and restricted species G carbonarius to the Canadian specimens It was later suggested by Reginald Pocock in 1913 that the two species G carbonarius and G scudderi were indeed the same and this has resulted in confusion over both the name to be used and number of species present in North America 4 Graeophonus anglicus has been found in the English Middle Coal Measures of Coseley Staffordshire Known from ten specimens that are now deposited in the British Museum the species was named by Reginald Pocock in 1911 5 However in 2018 researchers considered that the genus Graeophonus is invalid because the holotype specimen of G carbonarius Libellula carbonaria is poorly preserved and hard to identify as an amblypygid 1 Even in 1911 Pocock considered that the holotype specimen possibly did not belong to an amplypygid 5 More confusingly A I Petrunkevitch suggested to use another more complete specimen as the holotype in 1913 even though the original holotype specimen was not lost at that time To solve problems caused by this Jason A Dunlop erected a new genus Weygoldtina and placed most specimens of G carbonarius and G scudderi into Weygoldtina scudderi and G anglicus is renamed as Weygoldtina anglica 1 Morphology edit nbsp Tomographic left and illustrated right reconstruction of W anglica nbsp W scudderi had body length about 17 millimetres 0 67 in 1 Body length of W anglica ranges from 11 13 millimetres 0 43 0 51 in for complete specimens and the partly complete 18 millimetres 0 71 in long specimen shows a distinct pear shaped ocular tubercle on the carapace 4 CT data confirmed the presence of lateral eye tubercles 2 The center of the dorsal shield has a deep depression which probably acted as an attachment site for the muscles of the sucking stomach 2 Raptorial pedipalps were not mantis like shaped like most of modern amplypygid but similar to ones of modern genus Paracharon 2 Main difference of pedipalp compared to Paracharon is the spine orientation While the pedipalp spines in Paracharon appear to be almost parallel and slightly tilted outwards W anglica however the angle between the spines appears to be larger at least 90 degrees This character suggests that W anglica used its pedipalps not exactly in the same way as the modern Paracharon 6 Study in 2021 shows two prominent spines on each pedipalp which were not recognized before 6 Although first pairs of legs are not completely preserved they are probably long and antenna like same as modern amblypygids 2 Main difference of two species is anterior projection from the prosomal dorsal shield It is slightly wider shorter and more diffuse in W scudderi 1 Classification edit nbsp Photos of the only living paleoamblypygid tailless whip scorpion Paracharon caecus The morphology of both the abdomen and pedipalps in Weygoldtina is very similar to the modern genus Paracharon In 2007 Weygoldtina Graeophonus at that time was placed in Paracharontidae same family as Paracharon While Paracharon is notably blind this is thought to be a secondary result of living almost exclusively within termite mounds Thus the blindness was not considered a reason to exclude Graeophonus from Paracharontidae 4 However in 2017 Weygoldtina is rejected from Paracharontidae and treated as stem paleoamblypygid Paleoamblypygi is a monophyletic suborder that contains Paracharon Weygoldtina in addition Paracharonopsis cambayensis that is described from Eocene Cambay amber 2 In 2018 new family Weygoldtinidae is given for Weygoldtina 1 Differences in morphology of pedipalps and first pair of leg in Paracharon and Weygoldtina may show closer relationship of Paracharon and Euamblypygi but also this could be a point to an apomorphic condition of Weygoldtina Researchers claimed that it needs to be considered that Weygoldtina is not as similar to Paracharon as a brief look might suggest but is characterised by own specialisations 6 References edit a b c d e f g h Dunlop Jason A 2018 03 01 Systematics of the Coal Measures whip spiders Arachnida Amblypygi Zoologischer Anzeiger In honor of Peter Weygoldt 273 14 22 doi 10 1016 j jcz 2017 11 004 ISSN 0044 5231 a b c d e f Garwood Russell J Dunlop Jason A Knecht Brian J Hegna Thomas A 2017 The phylogeny of fossil whip spiders BMC Evolutionary Biology 17 1 105 doi 10 1186 s12862 017 0931 1 ISSN 1471 2148 PMC 5399839 PMID 28431496 Scudder S H 1876 A century of Orthoptera Decade VI Forficulariae North America Proceedings of the Boston Society of Natural History 18 257 264 a b c d e f Dunlop J A Zhou G R S Braddy S J 2007 The affinities of the Carboniferous whip spider Graeophonus anglicus Pocock 1911 Arachnida Amblypygi Earth and Environmental Science Transactions of the Royal Society of Edinburgh 98 2 165 178 doi 10 1017 S1755691007006159 S2CID 140582794 a b Petrunkevitch Alexander 1913 A Monograph of the Terrestrial Palaeozoic Arachnida of North America Yale University Press a b c Haug Carolin Haug Joachim T 2021 09 01 The fossil record of whip spiders the past of Amblypygi PalZ 95 3 387 412 doi 10 1007 s12542 021 00552 z ISSN 1867 6812 S2CID 232434849 Further reading editDunlop J A 1994 An Upper Carboniferous amblypygid from the Writhlington Geological Nature Reserve Proceedings of the Geologists Association 105 245 250 Retrieved from https en wikipedia org w index php title Weygoldtina amp oldid 1177040927, wikipedia, wiki, book, books, library,
