The name of this taxon should not be confused with that of the class Stenothecoida, a group of problematic Cambrian invertebrates that have a bivalved (dorsal and ventral) shell.[1]
Morphology
The group comprises conical laterally compressed shells that may be smooth or ornamented with folds or ribs.[3] The shells are broadly limpet-like, which led to their initial consideration as monoplacophoran molluscs.[1]
Taxonomy
The taxonomic position of the group is unclear;[4] it has been classified as a Yochelcionelloid or Helcionelloid.[5] It is not obviously in the stem group of any modern molluscan class, and has been referred to the monoplacophora,[3] although the monoplacophora are no longer considered to be a clade, and thus that classification means little more than "primitive mollusc".[6]
Genera
The family Stenothecidae consists of two subfamilies and the following genera:
1 2 Parkhaev P. Yu. 2001. Molluscs and siphonoconchs. In: Alexander E. M. et al. (eds.) The Cambrian biostratigraphy of the Stansbury basin, South Australia. Transactions of the Paleontological Institute, Russian Academy of Sciences, 282: 133–210, plates 24–54. Watsonellinae on the page 187.
↑ Budd, G. E.; Jensen, S. (2000). "A critical reappraisal of the fossil record of the bilaterian phyla". Biological Reviews of the Cambridge Philosophical Society. 75 (2): 253–95. doi:10.1111/j.1469-185X.1999.tb00046.x. PMID10881389.
↑ (in Russian)Missarzhevsky. (after 10 July) 1989. Drevneishie skeletnye okamenelosti i stratigrafiia pogranichnykh tolshch Dokembriia i Kembiia. (English translation: Oldest skeletal fossils and stratigraphy of Precambrian and Cambrian boundary beds.) Trudy Geologicheskogo Instituta, Akademia Nauk SSSR, 443, 237 pp., 32 plates. Mellopegmidae is on the page 179.
↑ Grabau A. W. 1900. Palaeontology of the Cambrian terranes of the Boston Basin. Occasional Papers of the Boston Society of Natural History 4:601–694.
This page is based on this Wikipedia article Text is available under the CC BY-SA 4.0 license; additional terms may apply. Images, videos and audio are available under their respective licenses.