''Cotyledion tylodes'' is an extinct, stalked
filter-feeder
Filter feeders are a sub-group of suspension feeding animals that feed by straining suspended matter and food particles from water, typically by passing the water over a specialized filtering structure. Some animals that use this method of feedin ...
known from the
Chengjiang
Chengjiang (; earlier Tchinkiang) is a city located in Yuxi, Yunnan Province, China, just north of Fuxian Lake.
Administrative divisions
Chengjiang City has 2 subdistricts and 4 townships.
;2 subdistricts
* Fenglu ()
* Longjie ()
;4 towns
...
lagerstatten. The living animal reached a couple of centimetres in height, and bore a loose
scleritome of ovoid sclerites. Its interpretation has been controversial, and it has been previously identified as a
carpoid
Homalozoa is an obsolete extinct subphylum of Paleozoic era echinoderms, prehistoric marine invertebrates. They are also referred to as carpoids.
Description
The Homalozoa lacked the typical pentamer body form of other echinoderms, but all were ...
echinoderm
An echinoderm () is any member of the phylum Echinodermata (). The adults are recognisable by their (usually five-point) radial symmetry, and include starfish, brittle stars, sea urchins, sand dollars, and sea cucumbers, as well as the s ...
,
or as a
stem group
In phylogenetics, the crown group or crown assemblage is a collection of species composed of the living representatives of the collection, the most recent common ancestor of the collection, and all descendants of the most recent common ancestor ...
echinoderm
An echinoderm () is any member of the phylum Echinodermata (). The adults are recognisable by their (usually five-point) radial symmetry, and include starfish, brittle stars, sea urchins, sand dollars, and sea cucumbers, as well as the s ...
.
''C. tylodes'' is now classified as a
stem group
In phylogenetics, the crown group or crown assemblage is a collection of species composed of the living representatives of the collection, the most recent common ancestor of the collection, and all descendants of the most recent common ancestor ...
entoprocta
Entoprocta (), or Kamptozoa , is a phylum of mostly sessile aquatic animals, ranging from long. Mature individuals are goblet-shaped, on relatively long stalks. They have a "crown" of solid tentacles whose cilia generate water currents that ...
based on new fossils that clearly show a U-shaped gut and a crown of tentacles.
See also
* ''
Dinomischus
''Dinomischus ''is a rare fossil animal from the Cambrian period. It reached 20 mm in height,
was attached to the sea floor by a stalk, and looked loosely like a flower. The cup-shaped body at the top of the stalk probably fed by filtering t ...
''
* ''
Siphusauctum
''Siphusauctum'' is an extinct genus of filter-feeding animals that lived during the Middle Cambrian about 510 million years ago. Attached to the substrate by a holdfast, it had a tulip-shaped body, called the calyx, into which it actively pumpe ...
''
References
Maotianshan shales fossils
Prehistoric protostome genera
{{Cambrian-animal-stub
Cambrian genus extinctions