Early Cambrian fuxianhuiids from China reveal origin of the gnathobasic protopodite in euarthropods

Citation:

J. Yang, J. Ortega-Hernández, D. A. Legg, T. Lan, J.-b. Hou, and X.-g.Zhang. 2018. “Early Cambrian fuxianhuiids from China reveal origin of the gnathobasic protopodite in euarthropods.” Nature Communications, 9, Pp. 470. Publisher's Version

Abstract:

Euarthropods owe their evolutionary and ecological success to the morphological plasticity of
their appendages. Although this variability is partly expressed in the specialization of the
protopodite for a feeding function in the post-deutocerebral limbs, the origin of the former
structure among Cambrian representatives remains uncertain. Here, we describe Alacaris
mirabilis gen. et sp. nov. from the early Cambrian Xiaoshiba Lagerstätte in China, which
reveals the proximal organization of fuxianhuiid appendages in exceptional detail. Proximally,
the post-deutocerebral limbs possess an antero-posteriorly compressed protopodite with
robust spines. The protopodite is attached to an endopod with more than a dozen podomeres,
and an oval flap-shaped exopod. The gnathal edges of the protopodites form an axial
food groove along the ventral side of the body, indicating a predatory/scavenging autecology.
A cladistic analysis indicates that the fuxianhuiid protopodite represents the phylogenetically
earliest occurrence of substantial proximal differentiation within stem-group Euarthropoda
illuminating the origin of gnathobasic feeding.
Last updated on 02/04/2018