Euproops Explained

Euproops is an extinct genus of xiphosuran, related to the modern horseshoe crab. It lived during the Carboniferous Period.

The Treatise on Invertebrate Paleontology describes Euproopidae as "small forms with wedge-shaped cardiac lobe bordered by distinct axial furrows, abdominal shield with annulated axis bearing a high boss on last segment." The same source describes Euproops as follows. "Prosoma with flat genal spines and carinate opthamalic spines; cardiopthamalic region with or without intercardiopthamalic area; abdomen with raised pleural ridges that cross flattened rim and are prolonged as marginal spines; annulated axis with knob on 1st and 3rd segments and elevated boss or short spine on hindmost segment; telson long."^[1]

Type species

Belinurus danae Meek & Worthen, 1865.^[2] = Euproops kilmersdonensis Ambrose & Romano, 1972 according to Anderson (1994);^[3] also E. gwenti and E. graigola, both from Upper Coal Measures strata in Wales, and E. darrahi from the Pennsylvanian Conemaugh Formation, Pennsylvania, USA according to Bicknell and Pates (2020).^[4]

E. danae is widely distributed, having also been recorded from the Mazon Creek Konservat-Lagerstätte, Carbondale Formation, Illinois, USA; the Beeman Formation, New Mexico, USA; Uffington Shale of West Virginia, USA; Riversdale Group, Canada; the Almaznaya Formation and Donets Black Coal Basin, Ukraine; Farrington Group, England, UK; Smolyaninovskaya Formation, Russia.

In 2021, a specimen of E. danae was discovered with an exceptionally well-preserved brain and central nervous system (CNS). It appears that the CNS of this (and perhaps other extinct horseshoe crabs) has remained essentially unchanged for some 300 m.y.^[5]

Other species

• Euproops mariae Crônier & Courville, 2004.^[6] from the Upper Carboniferous of the Graissessac Basin (Massif Central, France).
• Euproops rotundatus (Prestwich 1840). From the Upper Carboniferous of Coalbrookdale, Shropshire, England.^[7] Also recorded from Coal Measures at Westhoughton, England, UK; Upper Coal Measures in South Wales, UK; and Pennine Middle Coal Measures in Lancashire, England. The fine reconstruction of E. rotundatus by Filipiak and Krawczyński (1996) is based on material from the Orzesze Beds, Upper Silesian Coal Basin of Sosnowiec, Poland.^[8]
• Euproops anthrax Prestwich, 1840, Pennant Sandstone Formation (Upper Coal measures), Wales.
• Euproops longispina Packard, 1885, from the Carboniferous-aged Allegheny Formation, Pennsylvania, USA.^[9]
• Euproops cambrensis Dix and Pringle, 1929, from the Lower Coal Measures (Silesian, Westphalian) 15 yards above New Seam (= Gellideg Seam), Glamorgan, South Wales.^{[10] [11]}
• Euproops meeki Dix and Pringle, 1929, From the Carboniferous Upper Coal Measures of South Wales, UK.
• Euproops bifidus Siegfried, 1972, Flöz Dreibänke Formation, Upper Westphalian, Osnabrück, Lower Saxony, Germany.^[12]
• Euproops orientalis Kobayashi, 1933, from the Carboniferous-aged Jido Series, Korea.^[13]
• Euproops sp., so-called Piesproops, from the Carboniferous Osnabrück Formation, Piesberg quarry, Westphalian D, Osnabrück, Lower Saxony, Germany.

References

1. Størmer, L. 1955. Merostomata. Treatise on Invertebrate Paleontology, Part P Arthropoda 2, Chelicerata, P: 20.
2. Meek, F. B. & Worthen, A. H. 1865. Notice of some new types of organic remains from the Coal Measures of Illinois. Proceedings of the Academy of Natural Sciences of Philadelphia, 17, 41 - 45.
3. Anderson, L. I. 1994. Xiphosurans from the Westphalian D of the Radstock Basin, Somerset Coalfield, the South Wales Coalfield and Mazon Creek, Illinois. Proceedings of the Geologists' Association, 105, 265 - 275.
4. Bicknell, R. D. C. and Pates, S. (2020). Pictorial Atlas of Fossil and Extant Horseshoe Crabs, With Focus on Xiphosurida. ‘’Front. Earth Sci’’. ‘’’8’’’: 98. https://doi.org/10.3389/feart.2020.00098
5. https://www.nytimes.com/2021/08/18/science/brain-fossil-horseshoe-crab.html "This Brain Remained Intact in a 310 Million-Year-Old Fossil"
6. Crônier, C. & Courville, P., 2004. New xiphosuran merostomata from the Upper Carboniferous of the Graissessac Basin (Massif Central, France). C. R. Palevol 4 (2005), 123 – 133. https://doi.org/10.1016/j.crpv.2004.11.002
7. Prestwich, J. 1840. Memoir on the geology of Coalbrook Dale. Transactions of the Geological Society of London 5, 413 - 495. https://doi.org/10.1144/transgslb.5.3.413
8. Filipiak, P. & Krawczyński, W. 1996. Westphalian xiphosurans (Chelicerata) from the Upper Silesia Coal Basin of Sosnowiec, Poland. - Acta Palaeontologica Polonica 41, 4, 413 - 425.
9. Packard, A. S. (1885). On the Carboniferous xiphosurous fauna of North America. Mem. Natl. Acad. Sci. 3, 143 – 157. https://doi.org/10.5962/bhl.title.14755
10. Dix, E. and Pringle, J. (1929). On the fossil Xiphosura from the South Wales Coalfield with a note on the myriapod Euphoberia. Summ. Prog. Geol. Surv., 2, 90 – 114.
11. Euproops cambrensis Dix & Pringle, 1929. Amgueddfa Cymru — National Museum Wales, Palaeontology: Holotypes & Lectotypes. https://museum.wales/database/geology/palaeontology/?specimen=23
12. Siegfried, P. (1972). Ein Schwertschwanz (Merostomata, Xiphosurida) aus dem Oberkarbon von Ibbenbüren/Westf. Paläontol. Z. 46, 180 – 185. https://doi.org/10.1007/BF02990151
13. Kobayashi, T. (1933). On the occurrence of Xiphosuran remains in Chosen (Korea). Jpn J. Geol. Geogr. 10, 175 – 182.

Sources

• Fossils (Smithsonian Handbooks) by David Ward
• Leif Størmer, 1955, Merestomata, Treatise on Invertebrate Paleontology, Part P Arthropoda 2, Chelicerata, Geological Society of America and the University of Kansas, p. P20.

External links

• Xiphosura at Palaeos.com
• Bicknell R. D. C. and Pates S. (2020) Pictorial Atlas of Fossil and Extant Horseshoe Crabs, With Focus on Xiphosurida. Front. Earth Sci. 8:98