Original molluscan radula: Comparisons among Aplacophora, Polyplacophora, Gastropoda, and the Cambrian fossil Wiwaxia corrugata

@article{Scheltema2003OriginalMR,
  title={Original molluscan radula: Comparisons among Aplacophora, Polyplacophora, Gastropoda, and the Cambrian fossil Wiwaxia corrugata},
  author={A. Scheltema and K. Kerth and A. Kuzirian},
  journal={Journal of Morphology},
  year={2003},
  volume={257}
}
As the original molluscan radula is not known from direct observation, we consider what the form of the original radula may have been from evidence provided by neomenioid Aplacophora (Solenogastres), Gastropoda, Polyplacophora, and the Cambrian fossil Wiwaxia corrugata (Matthews). Conclusions are based on direct observation of radula morphology and its accessory structures (salivary gland ducts, radular sac, anteroventral radular pocket) in 25 species and 16 genera of Aplacophora; radula… Expand
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References

SHOWING 1-10 OF 39 REFERENCES
Aplacophora as Progenetic Aculiferans and the Coelomate Origin of Mollusks as the Sister Taxon of Sipuncula.
TLDR
Embryological development in sipunculans and mollusks shows a close relationship between them, and embryological development of the shell separates Aculifera and Conchifera, which supports the embryological and morphological relationships between Sipuncula and Mollusca. Expand
Discrimination and phylogeny of solenogaster species through the morphology of hard parts (Mollusca, Aplacophora, Neomeniomorpha).
Ten species in five genera and three families from continental shelf and deep-sea collections of neomenioid Aplacophora (Mollusca) are described, emphasizing external anatomy and hard parts--bodyExpand
Experimental and comparative morphology of radula renewal in pulmonates (Mollusca, Gastropoda)
SummaryThe continuous renewal of the pulmonate radula and the histology and regeneration of its concomitant epithelia were studied by light and electron microscopy, autoradiography and electronExpand
FORMATION AND HOMOLOGY OF RADULAR TEETH; A CASE STUDY USING COLUMBELLID GASTROPODS (NEOGASTROPODA: COLUMBELLIDAE)
TLDR
The results show that acuspate rachidian structures in the species the authors examined are not secreted by odontoblastic fields as has been shown for radular teeth in other taxa, but are instead produced independently by other secretory cell types. Expand
Two solenogaster molluscs, Ocheyoherpia trachia n.sp. from Macquarie Island and Tegulaherpia tasmanica Salvini-Plawen from Bass Strait (Aplacophora: Neomeniomorpha)
Tegulaherpia tasmanica Salvini-Plawen is herein redescribed and illustrated from 22 individuals collected in Bass Strait and expands the original text diagnosis to include illustrations. SimilaritiesExpand
Natural history of a solenogaster mollusc from Papua New Guinea, Epimenia australis (Thiele) (Aplacophora: Neomeniomorpha)
TLDR
Epimenia australis (Thiele) is a large, tropical, shallow-water neomenioid aplacophoran, or solenogaster, of the west Pacific, which is brightly coloured, with iridescent green and blue pactches on a reddish-brown background. Expand
Degradation of the radula in the snails Biomphalaria glabrata say and Limnaea stagnalis L. (Gastropoda, Pulmonata)
  • W. Peters
  • Biology, Medicine
  • Cell and Tissue Research
  • 2004
TLDR
The radula of snails is formed at the posterior end of the radular gland or pocket, and degraded at the same rate at its anterior end due to different secretory activities of the inferior epithelium of the Radular gland. Expand
Neue scandinavische Aplacophora (Mollusca, Aculifera)
TLDR
Diverse morphological and functional problems of the digestive system and of the pallial cavity are compared and discussed and it is stated that on the one hand the contents of the salivary glands dissolve tissue and that therefore the animals take their food mainly by sucking. Expand
The Middle Cambrian metazoan Wiwaxia corrugata (Matthew) from the Burgess Shale and Ogygopsis Shale, British Columbia, Canada
TLDR
While the possibilities of convergence cannot be eliminated, there appears to be a significant similarity between Wiwaxia and molluscs that suggests a related derivation from a turbellarian ancestor. Expand
Histology and regeneration of the radula of Pomacea bridgesi (Gastropoda, Prosobranchia)
SummaryHistology, physiological regeneration, and degradation of the taenioglossan prosobranch radula and its concomitant epithelia were studied by light and electron microscopy (TEM, SEM), electronExpand
...
1
2
3
4
...