Late Ordovician animals

Sacabambaspis is an extinct genus of armored jawless fish which lived in the Ordovician period. Sacabambaspis inhabited shallow waters on the continental margins of the southern supercontinent Gondwana. The most complete specimens have been found in Bolivia, while armor fragments are also known from Argentina, Australia, and Oman. Sacabambaspis vaguely resembles a slender tadpole, with an oversized armor-plated head, flat body, and no discernible fins outside of its narrow tail. The eyes are closely spaced and positioned at the very front of the head, akin to car headlamps. It was about long i

Astraspis ('star shield') is an extinct, monotypic genus of primitive jawless fish from the Ordovician of Central North America including the Harding Sandstone of Colorado and Bighorn Mountains of Wyoming. It is also known from Bolivia. It is related to other Ordovician fishes, such as the South American Sacabambaspis, and the Australian Arandaspis.