| Soomaspis splendida | |
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| Reconstruction ofSoomaspis splendida | |
| Scientific classification | |
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| Genus: | †Soomaspis |
| Species: | †S. splendida |
| Binomial name | |
| Soomaspis splendida Fortey & Theron, 1994 | |
Soomaspis is agenus of small to average size (about 3 cm or 1.2-inch long) marinearthropods in the Liwiidae Family, that lived during the lateOrdovician[1] (early Hirnantian).[2]Fossil remains ofSoomaspis were collected from theSoom ShaleLagerstätte inWestern Cape,South Africa.Soomaspis looks like a large, softagnostidtrilobite. It has a headshield (orcephalon) wider than the tailshield (pygidium), and in between them threethoracic body segments (somites). The genus ismonotypic, its solespecies beingSoomaspis splendida.
The name of the genus is a compound word of the deposit where the species was collected (the Soom Shale), and the Greek word"aspis" (shield). The species epithet,splendida comes from the Latin word"splendere" (brightness).
Soomaspis splendida is estimated to be over 3 cm (1.2 inches) along the axis,[3]1+1⁄2 times longer than wide. Thedorsalexoskeleton consists of a cephalon, apygidium and two or three thoracicsomites with articulating half-rings, all non-calcified, supposedly of medium convexity. The axis is poorly defined. The cephalon is transversely oval, widest at midlength. The cephalon is wider than the pygidium. Eyes are absent. Antennas are not known. The body is constricted at the three thoracic somites, so the animal gives the impression to have a waist. The pygidium is slightly wider than long, with the greatest width at midlength. The pygidium has a mid-ridge and five segments divided by clear furrows on the outer parts of the pleural field. The back edge of these furrows curve backwards, ending at a sharp angle to the pygidial margin.[1]
Soomaspis splendida has been collected from the Soom Shale (earlyHirnantian), Keurbos Farm, near Clanwilliam, Cape Province, South Africa.[1]
Soomaspis splendida was probably a marine bottom dweller. The Soom Shale is sometimes interfingered with the glacialtillite of the Pakhuis Formation, indicating thatSoomaspis lived in the open sea, near the edge of an ice sheet.[1]
