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| Reconstruction of Mesoproctus rayoli n. sp. and Cratosolpuga wunderlichi Selden, in Selden & Shear, 1996 in their paleoenvironment. Santana, Pinheiro, Silva & Lima,. 2024 Illustration by the paleoartist João Eudes. |
Abstract
Background:
A new fossil species of whipscorpion, Mesoproctus rayoli n. sp., is described. The specimen originates from the Crato Formation, dating to the Lower Cretaceous (Aptian/Albian) period within the Araripe Sedimentary Basin. This species has been provisionally assigned to Mesoproctus Dunlop, 1998, as it represents the sole known Thelyphonida fossil genus discovered in South America and within Araripe Lagerstätte.
Methods:
The material underwent detailed description and illustration processes. Key diagnostic characters, such as body length, pedipalpal coxae apophysis, the form of the opisthosoma, and the length of leg IV, were meticulously examined. SEM methods were applied in this study.
Results:
Through the detailed analysis, comparisons and differences to Mesoproctus rowlandi Dunlop, 1998 were made possible. Additionally, a well-preserved specimen of the rare camel spider, Cratosolpuga wunderlichi Selden, in Selden and Shear, 1996, was identified from the limestones of the Crato Formation. The newly discovered fossil specimen of Cratosolpuga wunderlichi suggests two characters not previously described: (i) a segmented tarsomere on leg IV; and (ii) a leg I with one tarsal claw.
Systematic paleontology
Order Thelyphonida Latreille, 1804
Thelyphonidae Lucas, 1835
Mastigoproctinae Speijer, 1933
Genus Mesoproctus Dunlop, 1998
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| Mesoproctus rayoli n. sp. Holotype MPSC A4295. Ventral view. Scale: 30 mm. |
Mesoproctus rayoli n. sp.
Diagnosis.—Body length including pygidium around 66 mm; pedipalpal coxae apophysis with one terminal tooth, one accessory tooth on the inner margin, outer margin of the apophysis serrated proximally; opisthosoma distinctly oval shaped; leg IV much longer than opisthosoma.
Etymology.—The specific epithet is in honor of Rafael Ribeiro Rayol, Brazilian federal attorney, who helped, along with the Brazilian Federal Police, in the retrieve of the material from the “Operation Santana Raptor”.
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| Reconstruction of Mesoproctus rayoli n. sp. and Cratosolpuga wunderlichi Selden, in Selden & Shear, 1996 in their paleoenvironment. Illustration by the paleoartist João Eudes. |
William Santana, Allysson P. Pinheiro, Thiago Andrade Silva and Daniel Lima. 2024. Description of A New fossil Thelyphonida (Arachnida, Uropygi) and further record of Cratosolpuga wunderlichi Selden, in Selden and Shear, 1996 (Arachnida, Solifugae) from Crato Formation (Aptian/Albian), Araripe Basin, Brazil. PeerJ. 12:e16670. DOI: 10.7717/peerj.16670