''Glomerula'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

polychaete worm Polychaeta () is a paraphyletic class of generally marine annelid worms, commonly called bristle worms or polychaetes (). Each body segment has a pair of fleshy protrusions called parapodia that bear many bristles, called chaetae, which are ma ...

in the family

Sabellidae Sabellidae, or feather duster worms, are a family of marine polychaete tube worms characterized by protruding feathery branchiae. Sabellids build tubes out of a tough, parchment-like exudate, strengthened with sand and bits of shell. Unlike th ...

. It differs from all other Sabellidae in having a calcareous tube and spinose

setae In biology, setae (; seta ; ) are any of a number of different bristle- or hair-like structures on living organisms. Animal setae Protostomes Depending partly on their form and function, protostome setae may be called macrotrichia, chaetae ...

. Only one living species, ''G. piloseta'', is known from

Lizard Island Lizard Island, also known as Jiigurru or Dyiigurra, is an island on the Great Barrier Reef in Queensland, Australia, northwest of Brisbane. It is part of the Lizard Island Group that also includes Palfrey Island, Queensland, Palfrey Island, and ...

, Great Barrier Reef, Australia. The oldest fossils of ''Glomerula'' are known from the Early

Jurassic The Jurassic ( ) is a Geological period, geologic period and System (stratigraphy), stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately 143.1 Mya. ...

and their tube microstructure has remained unchanged since then.

References

{{Taxonbar, from=Q2153277 Sabellida Extant Early Jurassic first appearances Annelid genera