Adult form of Planctosphaera pelagica, a hemichordate known, as of 2023, only by its tornaria larvae. Due to differences between larvae of…
Adult form of Planctosphaera pelagica, a hemichordate known, as of 2023, only by its tornaria larvae. Due to differences between larvae of acorn worms and that of Planctosphaera pelagica, Planctosphaera is sometimes given its own class.
Open the “Ecology, evolution, and paleontology” section on Wikipedia →
Source: List of unsolved problems in biology (CC BY-SA 4.0)