Duplapex

Duplapex Temporal range: Cambrian Stage 3 PreꞒ Ꞓ O S D C P T J K Pg N
Life restoration of Duplapex, based on the original description
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Order:	† Hymenocarina
Family:	† Tuzoiidae
Genus:	† Duplapex Ma et al. 2021
Species:	†D. anima
Binomial name
†Duplapex anima Ma et al. 2021

Duplapex is an extinct genus of bivalved arthropod known from the Cambrian Stage 3 aged Qingjiang biota of Hubei, China, with a single species. D. anima. It is thought to be a close relative of Tuzoia , but unlike it, the reticulated (net patterned) bivalved carapace was interpreted to have opened at a wide angle. The carapace had a pair of spines projecting posteriorly. ^[1] In its original description, it was suggested to have eyes on annulated stalks, but later research suggested that these may have been preservational artifacts instead. ^[2]

The general morphology of Duplapex differs from Tuzoia by its layered valves, unique ventral notches and doublure spines. These justified the erection of a new genus. ^[3]

References

1. Ma, Jiaxin; Lin, Weiliang; Liu, Cong; Sun, Ao; Wu, Yu; Wu, Yuheng; Fu, Dongjing (January 2022). "A new bivalved arthropod from the Cambrian (Stage 3) Qingjiang biota expands the palaeogeographical distribution and increases the diversity of Tuzoiidae" . Journal of the Geological Society. 179 (1): jgs2020–229. Bibcode:2022JGSoc.179..229M. doi:10.1144/jgs2020-229. ISSN   0016-7649.
2. Izquierdo-López, Alejandro; Caron, Jean-Bernard (December 2022). "The problematic Cambrian arthropod Tuzoia and the origin of mandibulates revisited". Royal Society Open Science. 9 (12): 220933. Bibcode:2022RSOS....920933I. doi:10.1098/rsos.220933. ISSN   2054-5703. PMC   9727825 . PMID   36483757. In Duplapex, the potential eye peduncles do not bear eyes [28], making their affinity ambiguous. Instead, these structures are most probably compression artefacts on the carapace margins
3. Ma, Jiaxin; Weiliang, Lin; Liu, Cong; Sun, Ao; Wu, Yu; Wu, Yuheng; Fu, Dongjing (January 2022). "A new bivalved arthropod from the Cambrian (Stage 3) Qingjiang biota expands the palaeogeographical distribution and increases the diversity of Tuzoiidae". Journal of the Geological Society. 179 (1). Bibcode:2022JGSoc.179..229M. doi:10.1144/jgs2020-229.