| Namapoikia Temporal range: (Terminal Ediacaran) | |
|---|---|
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Porifera (?) |
| Genus: | † Namapoikia Wood et al. 2002 |
| Species: | †N. rietoogensis |
| Binomial name | |
| †Namapoikia rietoogensis Wood et al. 2002 | |
Namapoikia rietoogensis is among the earliest known animals to produce a calcareous (probably aragonite [1] ) skeleton. [2] Known from the Ediacaran period, before the Cambrian explosion of calcifying animals, the long-lived organism grew up to a metre in diameter and resembles a colonial sponge. [3] [4] It was an encruster, filling vertical fissures in the reefs in which it originally grew. [5]
The fossil was first found in the Omkyk Member of the Nama Group from Rietoog in southern Namibia, in association with other calcifying fossils, Cloudina and Namacalathus .
Its mineralogy and accretionary style has been compared with that of the Lophotrochozoans, [6] though its unfamiliar morphology suggests a stem-group or deeper affiliation to this group. [7]
It grew in spurts, first emplacing an organic skeleton, then filling this in with aragonite. [3]
