Species Variety
Since 1947, a total of nine species have been described:
- D. costata Sprigg, 1947
- D. minima Sprigg, 1949
- D. spriggi Harrington et Moore, 1955
- D. elongata Glaessner et Wade, 1966
- D. tenuis Glaessner et Wade, 1966
- D. lissa Wade, 1972
- D. brachina Wade, 1972
- D. menneri Keller 1976, redescribed by Ivantsov, 2007 (=Vendomia menneri Keller 1976)
- D. rex Jenkins, 1992
From these, it is possible to consider only 4 or 5 of these 9 as valid species:
D. costata. (D. minima, D. spriggi, and D. elongata (holotype) are its junior synonyms). Unlike other species, D. costata has fewer, wider segments/isomers.
D. tenuis (D. brachina is it junior synonyms). Strongly resembles D. costata, differs from it by more narrow and numerous segments, sparingly lengthened oval form of the body.
D. lissa is very elongated (up to 15 cm), almost ribbon-like in shape, with the numerous thin isomers, the head and adjoining to it isomers are short. The fossil bears a distinct axial ledge consisting of two parallel bands extending from the head region to the posterior end of the body.
D. menneri is a small organism up to 8 mm in long, resembles juvenile D. costata by the small number of isomers and well-marked head formed through fused or undivided isomers. D. menneri differs from D. costata by its somewhat elongated form.
D. rex. This form was selected from the paratypes of the D. elongata. This Dickinsonia represented by only several very big specimens (up to more than 1 m in length), and has not a distinct determination. Big size is a major reason for select it into independent species and actually can be large specimens of the D. costata and/or D. tenuis.
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