Archisaccophyllia
kunmingensis
Phylum Cnidaria
Lingulella
chengiangensis
Phylum Brachiopoda
Geological
Time: Early Cambrian (~525 million years ago
Size (25.4mm=1
inch): Archisaccophyllia: 16 mm long, 5 mm across Lingulella 26 mm long,
4 mm across on a 110 mm by 55 mm matrix
Fossil
Site: Chengjiang Maotianshan Shales - Quiongzhusi Section, Yu’anshan
Member, Heilinpu Formation, Mafang Village, Anning, Kunming, Yunnan Province,
China
 Description:
This is an example of the incredible diversity of early life known
from the Chengjiang Biota. 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
original describers believe it is an early Cnidaian, a sea anemone
much like those to come later. The striated stem and rounded base
are indeed evocative of such an assignment. This
specimen is known as Archisaccophyllia kunmingensis, and differs
from Xianguangia by virtue of less tentacles (typically 12 vs 16)
and a more flexible body. Indeed while both have been considered
Cnidarians, the describers of this taxon feel Xianguagia is not
an actinarian. Archisaccophyllia seemed to be a gregarious animal;
a single colony of 15 m2 was found to posess over 350 individuals.
This specimen is found in association with a Lingullela brachiopod.
Reference:
Lethaia, Vol 38 pp 193-203 (2005).
Also
see: Chengjiang
Biota List Chengjiang
Fossils
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