|  Description:
The discovery of the Chengjiang Biota by Hou Xian-guang in 1984
resulted in a clear window on what is known as the Cambrian Explosion.The
diversity of soft-tissue fossils is astonishing: algae, medusiforms,
sponges, priapulids, annelid-like worms, echinoderms, arthropods
(including trilobites), hemichordates, chordates, and the first
agnathan fish make up just a small fraction of the total. Numerous
problematic forms are known as well, some of which may have represented
failed attempts at diversity that did not persist to the present
day.
The
Lobopodians are small marine and terrestrial animals termed colloquially
“velvet worms” or “worms with legs”. While
all Recent forms are terrestrial, most fossil Lobopodians are marine,
and are known primarily from the Cambrian. Six named  genera,
each with a single species, are known from the Chengjiang Biota,
making it the richest source of fossils of the type on Earth. This
one comes from Maotianshan (Mao Tian Hill), site of the discovery
of the Chengjiang Biota by Hou Xian-guang in 1984. This is one of
the most striking, and quite rare; as of 2004, only SIX examples
were known. A complete specimen is thought to be 15 mm, so this
one is typical. Each leg bears curved claws which are thought to
have served the creature as an adaptation to crawling on other organisms.
It has been found in association with sponges. It is most closely
related to Xenusion from the Early Cambrian of Germany, and is unknown
outside of Yunnan Province. This fine example has incredible detail,
with the long legs in clear evidence. A repaired matrix crack detracts
but little from a specimen that few have ever seen, much less possessed.
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