Vendiamorpha

---

title: "Vendiamorpha" type: doc version: 1 created: 2026-02-28 author: "Wikipedia contributors" status: active scope: public tags: ["vendiamorpha", "prehistoric-animal-classes"] description: "Extinct class of simple animals" topic_path: "general/vendiamorpha" source: "https://en.wikipedia.org/wiki/Vendiamorpha" license: "CC BY-SA 4.0" wikipedia_page_id: 0 wikipedia_revision_id: 0

::summary Extinct class of simple animals ::

| fossil_range = Late Ediacaran, between | image = Vendia_rachiata.JPG | image_caption = Paravendia janae, Vendia sokolovi, V. rachiata | taxon = Vendiamorpha | authority = Fedonkin, 1985 | subdivision_ranks = Families and genera | subdivision =

• Family Vendiidae Ivantsov (preliminary name)
  • Vendia Keller, 1969
  • Paravendia Ivantsov, 2004
  • Karakhtia ? Ivantsov, 2004

Vendiamorpha |first=M.A. |last=Fedonkin |year=1985 |article=Systematic description of Vendian metazoa |editor1-last=Sokolov |editor1-first=B.S. |editor2-last=Iwanowski |editor2-first=A.B. |title=Vendian System: Historical–Geological and Paleontological Foundation |volume=1: Paleontology |pages=70–106 |place=Moscow, RU |publisher=Nauka is a class of extinct animals within the Ediacaran phylum Proarticulata.

The typical vendiamorph had an oval-shaped or round-shaped body divided completely into segmented isomers, that were arranged alternately in two rows with reference to the longitudinal axis of the body.

Description

::figure[src="https://upload.wikimedia.org/wikipedia/commons/1/19/Karakhtia_nessovi.jpg" caption="''Karakhtia''"] ::

The phenomenon of left-right alternating segments is called glide reflection symmetry, and is a diagnostic feature of proarticulates. Transverse elements decrease in size from one end to the other and are inclined in the same direction. though, overwhelming evidence of them being proarticulates have since led researchers to discard this hypothetical relationship.

Some vendiamorphs (e.g., Vendia and Paravendia) supposedly demonstrate a digestive-distributive system consisting of a simple axial tube and lateral appendages, with one lateral appendage corresponding to one isomer.

Taxonomy

Vendiamorpha currently contains the singular Family Vendiidae (Originally Vendomiidae, derived from Vedomia, which was later synonymised into Dickinsonia.):

Vendiidae

• † Vendia Ivantsov, 2001
  • † Vendia sokolovi Keller, 1969
  • † Vendia rachiata Ivantsov, 2004
• † Paravendia Ivantsov, 2004
  • † Paravendia janae Ivantsov, 2004
• † Karakhtia ? Ivantsov, 2004
  • † Karakhtia nessovi Ivantsov, 2004

Due to the crumpled nature of most Karakhtia specimens and the aforementioned presence of coarse radial folds, the placement of it within Vendiamorpha, and Proarticulata itself, is tentative.

Distribution

All members of Vendiamorpha are restricted to the Ust' Pinega Formation of Syuzma and Onega Rivers in Arkhangelsk Oblast, northwestern Russia.

Name

The clade name Pseudovendia refers to the resemblances to a fossil imprint described as Vendia sokolovi. Originally, that fossil was interpreted as an arthropod, later as a proarticulatan,

Current scientific consensus now recognizes the poorly preserved holotype of Pseudovendia as a pseudofossil.

References

References

1. Menner, V.V.. (1963). "Stratigraphy of the USSR: Upper Precambrian". Gos. Nauchno-Tekh. Izd..
2. (1971). "''Praecambridium'' - a primitive arthropod". Lethaia.
3. (April 2007). "Small Vendian transversely Articulated fossils". Paleontological Journal.
4. Ivantsov, A.Yu. (2001). "''Vendia'' and Other Precambrian "Arthropods"". Paleontological Journal.
5. Ivantsov, A.Yu. (2004). "New Proarticulata from the Vendian of the Arkhangel'sk region". Paleontological Journal.
6. (2004). "Some problematic fossils from the Vendian of the south-eastern White Sea region". Paleontological Journal.
7. (January 2004). "Some problematic fossils from the Vendian of the southeastern White Sea Region". Paleontological Journal.
8. (1 March 1984). "The Vendian as the Terminal System of the Precambrian". Episodes.
9. (1979). "''Pseudovendia charnwoodensis'' — A new Precambrian arthropod from Charnwood Forest, Leicestershire". Mercian Geologist.
10. Boynton, H.E.. (2010). "Charnian fossils in the outwoods". Mercian Geologist.
11. Grazhdankin, D.V.. (2007). "Charnwood biota as seen from arctic Russia – Ediacarans and their environments". [[University of Leicester]].
12. (2010). "Effaced preservation in the Ediacara biota and its implications for the early macrofossil record". Palaeontology.

::callout[type=info title="Wikipedia Source"] This article was imported from Wikipedia and is available under the Creative Commons Attribution-ShareAlike 4.0 License. Content has been adapted to SurfDoc format. Original contributors can be found on the article history page. ::