Xiaoya Maa, Xianguang Hou and Jan Bergstrom have reported new material of the lobopodian Luolishania longicruris from the Lower Cambrian Chengjiang Lagerstatte, southwest China. As many of you might known that Chengjiang Maotianshan Shales in China is home to thousands of exceptionally preserved soft-bodied fossils and hence regarded as fossil paradise .The discovery of Chengjiang biota by Hou Xian-guang in 1984 offered us a very clear means of observing Cambrian explosion ,which is considered as rapid burst of complex life forms around 530 million years ago.The great antiquity and the excellent soft-body preservation in the Chengjiang Lagersta¨ tte have provided a unique insight into the origin and evolution of early metazoan animals.

Lobopodians are small, segmented animals ,initially included some extant animal groups of onychophorans and tardigrades but after the first onychophoran-like fossil was described from the Middle Cambrian Burgess Shale ,‘‘lobopodians’’ have also been used to include the extinct groups.But in strict sense lobopodia is a phylum containing Dinocaridida and Xenusia only:
Dinocaridida iis a extinct taxon of fossil arthropod-like marine animals found in the early and middle Cambrian. It is subdivided into the anomalocarids and the opabinids.
The Xenusiids are a group of lobopods resembling Xenusion.They have relatively large, annulated, cylindrical body. Their lobopod legs have tubercles at their bases. Some have large frontal appendages.

After the discovery of first two lobopdians in Microdictyon sinicum and Luolishania longicruris from Chengjiang Lagerstatte ,six more lobopodian species were discovered. The discovery of new material of Luolishania longicruris by Xiaoya Maa, Xianguang Hou and Jan Bergstrom throws more light on on several morphological features of the species, including the paired antenniform outgrowths, eyes, head shield, setae and other cuticular projections, as well as the differentiated sclerites, appendages, claws, and lobopod interspaces. The findings are published in online edition of journal Arthropod Structure & Development which includes some breathtaking images of the amazing fossil. Luolishania longicruria shows well developed tagmosis, meaning that it has a distinct head and a trunk. Authors also performed cladistic analysis which shows that L. longicruris may be an important representative of the stem lineage leading to arthropods. There is always lots of discussion about onychophora ( sister broup of arthropods) and cambrian lobopodians ,after this study authors are of opinion that Onychophorans almost certainly originated from a Cambrian lobopodian, but their exact phylogenetic position is unresolved.As Cambrian lobopodians seem to be paraphyletic or even polyphyletic, which enables them to support previous view that the name Onychophora should not be extended to include all Cambrian lobopodians.

Reference:
Morphology of Luolishania longicruris (Lower Cambrian, Chengjiang Lagerstätte, SW China) and the phylogenetic relationships within lobopodians.
Ma X, Hou X, Bergström J.
Arthropod Struct Dev. 2009 Mar 14.

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