Onychodictyon
| Onychodictyon Temporal range: | |
|---|---|
| O. ferox fossil, Geological Museum of China | |
| Scientific classification | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Clade: | Panarthropoda |
| Phylum: | †"Lobopodia" |
| Class: | †Xenusia |
| Order: | †Paronychophora |
| Family: | †Onychodictyidae |
| Genus: | †Onychodictyon Hou, Ramsköld, & Bergström, 1991 |
| Type species | |
| Onychodictyon ferox Hou, Ramsköld, & Bergström, 1991 | |
| Species | |
| |
Onychodictyon is a genus of extinct lobopodian known from the Lower Cambrian Chengjiang Maotianshan Shales in the Yunnan Province in China. It was characterized by a stout body covered by fleshy papillae and pairs of sclerotized plates with spines, representing part of the diverse "armoured lobopodians" alongside similar forms such as Microdictyon and Hallucigenia.
The maximum length of Onychodictyon is 70 mm (2.8 in). It has a resemblance to Microdictyon (net-like sclerite ornament) but also Aysheaia and tardigrades (basally-fused terminal leg pairs). Each leg has a pair of curved claws that are thought to have aided Onychodictyon in climbing onto other organisms. By having a unique anterior end structure, Onychodictyon may have been a deposit feeder which means that they would scavenge for organic material from the seafloor. Onychodictyon sclerites appear to have molted with some specimens exhibiting perfectly conjoined plates from successive molts.
Onychodictyon is represented by two species: O. ferox which has a pair of simple eyes and feathery antenniform appendages on its head; and O. gracilis which has a blunt front end without evidence of any appendages.