Reconstruction of Kuamaia lata, from Hou and Bergström (1997).

Belongs within: Trilobitomorpha.

The Conciliterga are a group of soft-bodied arthropods related to trilobites known from the Lower and Middle Cambrian Burgess Shale and Chengjiang faunas.

Synapomorphies (from Cotton & Braddy 2004, not including Australimicola): Dorsal bulge present in exoskeleton accomodating drop-shaped ventral eyes; anteromedian margin of cephalon notched, accomodating strongly sclerotised plate; distal lobe of exopod large, teardrop-shaped, with long attachment to proximal lobe; joints between posterior tergites functional, anterior ones variably fused. (Running data matrix from Legg et al. (2013) through TNT identifies only one synapomorphy for Conciliterga including Australimicola: mediolateral spines present.)

Conciliterga [Helmetiida]
    |--Australimicola LSE13
    `--+--+--Skioldia LSE13
       |  `--+--Saperion glumaceum Hou et al. 1991 LSE13, CB04
       |     `--Tegopelte Simonetta & Delle Cave 1975 LSE13, CB04
       |          `--T. gigas Simonetta & Delle Cave 1975 CB04
       `--+--Nathorstia Walcott 1912 B95
          `--Helmetiidae CB04
               |--Helmetia Walcott 1918 CB04
               |    `--H. expansa Walcott 1918 CB04
               |--Rhombicalvaria Hou 1987 CB04, B95
               |    `--R. acantha Hou 1987 CB04
               `--Kuamaia Hou 1987 CB04, B95
                    |--K. lata Hou 1987 CB04
                    `--K. muricata Hou & Bergström 1997 CB04

*Type species of generic name indicated


[B95] Bousfield, E. L. 1995. A contribution to the natural classification of Lower and Middle Cambrian arthropods: Food-gathering and feeding mechanisms. Amphipacifica 2: 3–34.

[CB04] Cotton, T. J., & S. J. Braddy. 2004. The phylogeny of arachnomorph arthropods and the origin of the Chelicerata. Transactions of the Royal Society of Edinburgh: Earth Sciences 94: 169–193.

[LSE13] Legg, D. A., M. D. Sutton & G. D. Edgecombe. 2013. Arthropod fossil data increase congruence of morphological and molecular phylogenies. Nature Communications 4 (2485): 1–7.

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