Duplapex Explained

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]

Notes and 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 . en . 179 . 1 . jgs2020–229 . 10.1144/jgs2020-229 . 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 . en . 9 . 12 . 220933 . 10.1098/rsos.220933 . 2054-5703 . 9727825 . 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.