Siphusauctum is an extinct genus of filter-feeding animals that lived during the Middle Cambrian about 510 million years ago.

It had a tulip-shaped body, called the calyx, into which it actively pumped water that entered through pores and filtered out and digested organic contents.

[3] Siphusauctum gregarium was described in 2012 from numerous fossils recovered from the "Tulip Beds" strata of the Burgess Shale of Yoho National Park, British Columbia, Canada.

The generic name comes Latin siphus ("cup" or "goblet") and auctus ("large"), referring to the general shape and size of the animal.

[1] However, later studies suggested that it was likely a member of the stem-group of Ctenophora (comb jellies) instead, due to sharing characteristic large cillia structures with the group.