An Early Cambrian Radula

@inproceedings{Butterfield2008AnEC,
  title={An Early Cambrian Radula},
  author={Nicholas J.F. Butterfield},
  booktitle={Journal of Paleontology},
  year={2008}
}
Abstract Microscopic teeth isolated from the early Cambrian Mahto Formation, Alberta, Canada, are identified as components of a molluscan radula, the oldest on record. Tooth-rows are polystichous and lack a medial rachidian tooth-column. Anterior-posterior differences in tooth-row morphology are interpreted as ontogenetic and correspond broadly to the diversity of isolated teeth, some of which correspond closely with those of extant aplacophoran molluscs. Associated pock-marked cuticular… Expand
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References

SHOWING 1-10 OF 90 REFERENCES
A soft-bodied mollusc with radula from the Middle Cambrian Burgess Shale
TLDR
Odontogriphus omalus is interpreted to be members of an early stem-group mollusc lineage that probably originated in the Neoproterozoic Ediacaran Period, providing support for the retention of a biomat-based grazing community from the late Precambrian Period until at least the Middle Cambrian. Expand
Fossilized soft tissues in a Silurian platyceratid gastropod
TLDR
A Silurian platyceratid gastropod from the Herefordshire Lagerstätte that preserves the oldest soft tissues yet reported from an undoubted crown-group mollusc is described, providing support for an attached mode of life, and suggestive of a coprophagous feeding strategy. Expand
The Early Cambrian Halkieria is a mollusc
TLDR
It is found that all the characters that can be observed with certainty are compatible with characters in living molluscs and there is no support for theories that regard Halkieria as belonging to the stem group of either the annelids or brachiopods. Expand
Articulated Palaeozoic fossil with 17 plates greatly expands disparity of early chitons
TLDR
The highly conserved body plan of living chitons belies the broad disparity of this clade during the Palaeozoic era. Expand
Original molluscan radula: Comparisons among Aplacophora, Polyplacophora, Gastropoda, and the Cambrian fossil Wiwaxia corrugata
TLDR
The original molluscan radula was similar to the radula found in Helicoradomena species, and it is shown that distichy also occurs during early development in several species of gastropods and polyplacophorans. Expand
The Largest Cambrian Animal, Anomalocaris, Burgess Shale, British Columbia
TLDR
It is suggested that this animal, the largest known from Cambrian rocks, swam by using the series of closely spaced lateral lobes essentially as a lateral fin along which waves of motion were propagated. Expand
Beaks and radulae of Early Carboniferous goniatites
TLDR
The goniatite beaks from the Late Mississippian of Arkansas resemble those in living coleoids in the relative length of the outer and inner lamellae in the upper beak, which probably indicates similarity in muscle insertion. Expand
Early Palaeozoic diversification of chitons (Polyplacophora, Mollusca) based on new data from the Silurian of Gotland, Sweden
Isolated, well-preserved silicified sclerites of an unusually diverse Silurian paleoloricate assemblage from Gotland preserve morphological features that are important in interpreting palaeobiology.Expand
A comparative study of Lower Cambrian Halkieria and Middle Cambrian Wiwaxia
TLDR
The interpretation of sachitid sclerites as protective armour is an alternative to the interpretation by Jell (1981, Alcheringa 5) that sachits were respiratory organs in an animal of probable annelid affinities. Expand
Hooking some stem‐group “worms”: fossil lophotrochozoans in the Burgess Shale
  • N. Butterfield
  • Biology, Medicine
  • BioEssays : news and reviews in molecular, cellular and developmental biology
  • 2006
TLDR
Analysis of the fossil record of two famously problematic worms, Odontogriphus and Wiwaxia, reveals pronounced anatomical and histological discrepancies with molluscan analogues, such that they are more reliably interpreted as primitive features of the superphylum Lophotrochozoa. Expand
...
1
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3
4
5
...