#ooedigera

[ornithopsis]

Ooedigera peeli (”Peel’s old egg”), a vetulicolian from the Cambrian of Greenland.

Vetulicolians are among the most enigmatic of all extinct animals. They have pharyngeal slits like a chordate and a segmented tail like an arthropod. They are commonly considered to be one of the earliest groups of deuterostomes—the group containing echinoderms, vertebrates, and their relatives—but they have also been considered to be relatives of arthropods or kinorhynchs.