Pilargidae is a

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

polychaete Polychaeta () is a paraphyletic class (biology), class of generally marine invertebrate, marine annelid worms, common name, commonly called bristle worms or polychaetes (). Each body segment has a pair of fleshy protrusions called parapodia that ...

s. These marine worms are cylindrical, somewhat flattened, and can be ribbon-like. They can be found free-living on sediment, or shallowly in sediment. Some species within the genera Hermundura and Litocorsa are known to burrow, having reduced heads and

parapodia In invertebrates, the term parapodium ( Gr. ''para'', beyond or beside + ''podia'', feet; plural: parapodia) refers to lateral outgrowths or protrusions from the body. Parapodia are predominantly found in annelids, where they are paired, unjointed ...

. Two species are known to be commensal with other polychaetes. ''Pilargis berkeleyae'' will live in the tubes of

Chaetopteridae The Chaetopteridae are a family of marine filter-feeding polychaete worms that live in vertical or U-shaped tubes in tunnels buried in the sedimentary or hard substrate of marine environments. The worms are highly adapted to the hard tube they s ...

, and ''Ancistrosyllis commensalis'' will live in

Capitellidae Capitellidae is a polychaete worm family in the subclass Scolecida. Genera * ''Abyssocapitella'' * ''Amastigos'' * ''Anotomastus'' * ''Baldia (worm), Baldia'' * ''Barantolla'' * ''Branchiocapitella'' * ''Capitella'' * ''Capitellethus'' * ''Cap ...

burrows. Pilargid worms are almost all exclusively

predator Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...

s, classified as

carnivore A carnivore , or meat-eater (Latin, ''caro'', genitive ''carnis'', meaning meat or "flesh" and ''vorare'' meaning "to devour"), is an animal or plant whose food and energy requirements derive from animal tissues (mainly muscle, fat and other sof ...

omnivores An omnivore () is an animal that has the ability to eat and survive on both plant and animal matter. Obtaining energy and nutrients from plant and animal matter, omnivores digest carbohydrates, protein, fat, and fiber, and metabolize the nutri ...

. They are similar in appearance to

Hesionidae Hesionidae are a family of phyllodocid "bristle worms" (class Polychaeta). They are (like almost all polychaetes) marine organisms. Most are found on the continental shelf; '' Hesiocaeca methanicola'' is found on methane ice, where it feeds ...

, with a

peristomium The peristomium is the first true body segment in an annelid worm's body in the anterior end. It is directly behind the prostomium and contains the mouth, tentacular cirri, and sometimes feeding palps, which may instead occur on the prostomium. If ...

often with two pairs of tentacular cirri (with 1 pair or 0 in some species), reduced or absent

notopodia In invertebrates, the term parapodium ( Gr. ''para'', beyond or beside + ''podia'', feet; plural: parapodia) refers to lateral outgrowths or protrusions from the body. Parapodia are predominantly found in annelids, where they are paired, unjointed ...

, and a lack of pharyngeal jaws. The first few segments bearing setigers are also somewhat fused. They can have 0 to 3 antennae, and palps. These

polychaetes 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 mad ...

are rarely the most abundant polychaete.

Contested genera

Some genera have been redescribed under a new genus, which some consider junior synonyms of existing genera. '' Parandalia tricuspis'' is a redescription of Hermundura tricuspis, which provided more reliable characteristics for identification.

References

External links

Polychaetes Annelid families {{Annelid-stub