An exceptionally preserved arthropod cardiovascular system from the early Cambrian.
The assumption that amongst internal organs of early arthropods only the digestive system withstands fossilization is challenged by the identification of brain and ganglia in early Cambrian fuxianhuiids and megacheirans from southwest China. Here we document in the 520-million-year-old Chengjiang arthropod Fuxianhuia protensa an exceptionally preserved bilaterally symmetrical organ system corresponding to the vascular system of extant arthropods. Preserved primarily as carbon, this system includes a broad dorsal vessel extending through the thorax to the brain where anastomosing branches overlap brain segments and supply the eyes and antennae. The dorsal vessel provides segmentally paired branches to lateral vessels, an arthropod ground pattern character, and extends into the anterior part of the abdomen. The addition of its vascular system to documented digestive and nervous systems resolves the internal organization of F. protensa as the most completely understood of any Cambrian arthropod, emphasizing complexity that had evolved by the early Cambrian.
1] Yunnan Key Laboratory for Palaeobiology, Yunnan University, Kunming 650091, China [2] Department of Earth Sciences, The Natural History Museum, Cromwell Road, London SW7 5BD, UK.
Xiaoya
X
Ma
Yunnan Key Laboratory for Palaeobiology, Yunnan University, Kunming 650091, China.
Peiyun
P
Cong
Yunnan Key Laboratory for Palaeobiology, Yunnan University, Kunming 650091, China.
Xianguang
X
Hou
Department of Earth Sciences, The Natural History Museum, Cromwell Road, London SW7 5BD, UK.
Gregory D
GD
Edgecombe
Department of Neuroscience and Center for Insect Science, University of Arizona, Tucson, Arizona 85721, USA.
Nicholas J
NJ
Strausfeld
D000818:Animals; D001181:Arthropods / Q000033:anatomy & histology*; D002319:Cardiovascular System / Q000033:anatomy & histology*; D002681:China; D005580:Fossils