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Pygmaclypeatus; Temporal range: Chengjiang PreꞒ Ꞓ O S D C P T J K Pg N ↓
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Arthropoda
(unranked):	†Artiopoda
Genus:	†Pygmaclypeatus; Zhang et al., 2000
Species:	†P. daziensis
Binomial name
	†Pygmaclypeatus daziensis; Zhang et al., 2000

Pygmaclypeatus is a genus of trilobite-like arthropod from the Cambrian aged Chengjiang biota of southern China.^[1] The carapace is flat and broad, and slightly shorter than it is wide, reaching a maximum width of 17.5 millimetres (0.69 in) and length of 14 millimetres (0.55 in). The headshield makes up about 25% of the total length, and has attached a pair of antennae, as well as four pairs of biramous limbs. The trunk has 6 tergites, each associated with a pair of biramous limbs along with a terminal pygidium associated with four pairs of biramous appendages and a segmented short tailspine. The well developed paddle-like exopodites on the trunk and pygidium limbs along with its small size suggests that it was an effective swimmer with a strong power stroke, and that it probably had a nektobenthic mode of life, swimming close to the ocean floor. Given its delicate spinose endites on the limbs it likely only consumed soft food and organic particles. It is considered to be closely related to Retifacies from the same deposit with shared characters including a segmented tailspine. It has been placed as a member of Artiopoda, possibly along with Retifacies the earliest diverging lineage of the Trilobitomorpha.^[2]

References

^ Zhang, X.; Han, J.; Shu, D. (2000). "A New Arthropodpygmaclypeatus Daziensisfrom the Early Cambrian Chengjiang Lagerstätte, South China". Journal of Paleontology. 74 (5): 979. doi:10.1666/0022-3360(2000)074<0979:ANAPDF>2.0.CO;2. S2CID 131279534.
^ Schmidt, Michel; Hou, Xianguang; Zhai, Dayou; Mai, Huijuan; Belojević, Jelena; Chen, Xiaohan; Melzer, Roland R.; Ortega-Hernández, Javier; Liu, Yu (2021-08-19). "Before trilobite legs: Pygmaclypeatus daziensis reconsidered and the ancestral appendicular organization of Cambrian artiopods". doi:10.1101/2021.08.18.456779. S2CID 237261790. {{cite journal}}: Cite journal requires |journal= (help)