Below, you see a list with possible ichnogenera for a spherical or hemispherical, lined, passively filled, (sub)vertical, unbranched burrow. Click on them to get detailed descriptions of the ichnogenus and a list of its ichnospecies. (Please allow for pop-up windows):

• Feoichnus (Ichnogenus includes ornamented ichnospecies)
• Fontanai (Taxonomical status unclear, use not recommended)