Planaterga

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Planaterga
Temporal range: Middle Ordovicianpresent, 467.3–0  Ma
Limuloides limuloides specimen In 60018.jpg
Fossil of Limuloides limuloides , a bunodid
Eatoniana namaquensis 46890827.jpg
Eatoniana namaquensis , a mite arachnid
Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Chelicerata
Clade: Prosomapoda
Clade: Planaterga
Lamsdell, 2013
Groups

Planaterga is a clade of prosomapod euchelicerates including several synziphosurid genera (mainly bunodids and pseudoniscids) and the group Dekatriata (which in turn includes arachnids, chasmataspidids and eurypterids). [1] Planaterga is defined by the opisthosoma with tergites broadest at third or fourth and lacking enlarged axial nodes, carapace (prosomal dorsal shield) with reduced genal spines, as well as somite VII (first opisthosomal segment) with reduced appendages and microtergite. [1]

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References

  1. 1 2 Lamsdell, James C. (2012-12-18). "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.