| Changchengia Temporal range:Statherian–Calymmian | |
|---|---|
 | |
| Reconstruction ofChangchengia stipitata | |
Scientific classification | |
| Domain: | Eukaryota |
| Kingdom: | incertae sedis |
| Genus: | †Changchengia Yan & Liu, 1997 |
| Species: | †C. stipitata |
| Binomial name | |
| †Changchengia stipitata Yan and Liu, 1997 | |
Changchengia is a genus of possiblealga from the early-midProterozoic. It contains one species,Changchengia stipitata. This genus is known from various formations, such as the Olive Shales of theVindhya Range[1] and the Saraipali Formation in India,[2] alongside theChuanlinggou Formation of China.[3]
Changchengia is between 0.7 and 40 mm (0.03 and 1.57 in) long and between 0.5 to 4 mm (0.02 to 0.16 in) wide, with a thin blade-likethallus. InC. stipitata the thallus is usually ribbon-shaped orlanceolate with folded andlamellose margins, with the widest point in the middle and tapering towards the base and tip. However, fossils from the Chuanlinggou Formation are more ovoid orobcordate in shape, alongside tapering holdfasts. The base is obtuse and contacts with a long and linear parastem, which itself connects to a holdfast. This genus shares many morphological similarities withTuanshanzia, and in fact it was classified within this genus at first.[2] However, a conspicuous difference between the two is thatTuanshanzia has no parastem, and instead its thallus slowly narrows towards the holdfast.
