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Legrandella
Temporal range: Devonian
Reconstruction of Legrandella lombardii
Fossils of L. lombardii, holotype (A–C, E, F) and plastoparatype (D)
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Chelicerata
Clade: Euchelicerata
Clade: Prosomapoda
Genus: Legrandella
Eldredge, 1974
Type species
Legrandella lombardii
Eldredge, 1974

Legrandella is a genus of synziphosurine, [1] a paraphyletic group of fossil chelicerate arthropods. [2] [3] Legrandella was regarded as part of the clade Prosomapoda. [2] [4] [5] [6] [3] [7] Fossils of the single and type species, L. lombardii, have been discovered in deposits of the Devonian period in Cochabamba, Bolivia. [7] [2]

The prosoma of Legrandella covered by a vaulted carapace with anterior projection, blunt genal cornua (posterolateral corners), humped cardiac lobe and pairs of radiated grooves. [1] Alongside Pseudoniscus roosevelti, Legrandella lombardii is one of the few synziphosurine species that confirmed to have lateral compound eyes. [8] The eyes are slit-like, located just below the ophthalmic ridges on each side of the carapace. [1] The opisthosoma is externally 11-segmented, subdivided into a 8-segmented preabdomen and 3-segmented postabdomen. [1] Tergite of the 1st preabdomimal segment is a reduced microtergite while the remaining 7 tergite possess axial nodes and spine-like tergopleurae (lateral extension). [1] each of the postabdominal segment is cylindrical and bore reduced tergopleurae. [1] The telson is triangular in cross section, but the distal region is yet to be discovered. [1]

References

  1. ^ a b c d e f g Eldredge, Niles; Smith, LeGrande (1974). "Revision of the suborder Synziphosurina (Chelicerata, Merostomata) : with remarks on merostome phylogeny. American Museum novitates ; no. 2543". hdl: 2246/2745. {{ cite journal}}: Cite journal requires |journal= ( help)
  2. ^ a b c Lamsdell, James C. (2013). "Revised systematics of Palaeozoic 'horseshoe crabs' and the myth of monophyletic Xiphosura". Zoological Journal of the Linnean Society. 167 (1): 1–27. doi: 10.1111/j.1096-3642.2012.00874.x. ISSN  0024-4082.
  3. ^ a b Bicknell, Russell D. C.; Pates, Stephen (2020). "Pictorial Atlas of Fossil and Extant Horseshoe Crabs, With Focus on Xiphosurida". Frontiers in Earth Science. 8: 98. Bibcode: 2020FrEaS...8...98B. doi: 10.3389/feart.2020.00098. ISSN  2296-6463.
  4. ^ Selden, Paul A.; Lamsdell, James C.; Qi, Liu (2015). "An unusual euchelicerate linking horseshoe crabs and eurypterids, from the Lower Devonian (Lochkovian) of Yunnan, China". Zoologica Scripta. 44 (6): 645–652. doi: 10.1111/zsc.12124. ISSN  0300-3256. S2CID  55264483.
  5. ^ Lamsdell, James C.; Briggs, Derek E. G.; Liu, Huaibao P.; Witzke, Brian J.; McKay, Robert M. (2015). "A new Ordovician arthropod from the Winneshiek Lagerstätte of Iowa (USA) reveals the ground plan of eurypterids and chasmataspidids". The Science of Nature. 102 (9–10): 63. Bibcode: 2015SciNa.102...63L. doi: 10.1007/s00114-015-1312-5. ISSN  0028-1042. PMID  26391849. S2CID  8153035.
  6. ^ Bicknell, Russell D. C.; Lustri, Lorenzo; Brougham, Tom (2019-12-01). "Revision of "Bellinurus" carteri (Chelicerata: Xiphosura) from the Late Devonian of Pennsylvania, USA". Comptes Rendus Palevol. 18 (8): 967–976. doi: 10.1016/j.crpv.2019.08.002. ISSN  1631-0683.
  7. ^ a b Dunlop, J. A.; Penney, D.; Jekel, D. (2020). "A summary list of fossil spiders and their relatives" (PDF). World Spider Catalog. Natural History Museum Bern. pp. 1–296.
  8. ^ Bicknell, Russell D. C.; Amati, Lisa; Ortega-Hernández, Javier (2019-11-14). "New insights into the evolution of lateral compound eyes in Palaeozoic horseshoe crabs". Zoological Journal of the Linnean Society. 187 (4): 1061–1077. doi: 10.1093/zoolinnean/zlz065. ISSN  0024-4082.