Soomaspis is a genus of small to average size (about 3 cm or 1.2-inch long) marine arthropods in the Liwiidae Family, that lived during the late Ordovician (early Hirnantian). Fossil remains of Soomaspis were collected from the Soom Shale Lagerstätte in Western Cape, South Africa. Soomaspis looks like a large, soft agnostid trilobite. It has a headshield (or cephalon) wider than the tailshield (pygidium), and in between them three thoracic body segments (somites). The genus is monotypic, its sole species being Soomaspis splendida.