Hyolithellus

Hyolithellus Temporal range: Lower Cambrian – Middle Cambrian[1] PreꞒ Ꞓ O S D C P T J K Pg N
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Stem group:	Annelida
Genus:	†Hyolithellus Billings, 1871

Hyolithellus is a conical tubular fossil from the Cambrian, originally considered a hyolith but since reinterpreted tentatively as an annelid worm.^[1]

Its circular, thin (15–150 μm), originally phosphatic tube gets wider along its long, undulating, annulated length.^[1]