Palpata
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Palpata is a subclass of
polychaete Polychaeta () is a paraphyletic class of generally marine Annelid, annelid worms, common name, commonly called bristle worms or polychaetes (). Each body segment has a pair of fleshy protrusions called parapodia that bear many bristles, called c ...
worm. Members of this subclass are mostly deposit feeders on marine detritus or
filter feeder Filter feeders are aquatic animals that acquire nutrients by feeding on organic matters, food particles or smaller organisms (bacteria, microalgae and zooplanktons) suspended in water, typically by having the water pass over or through a s ...
s. Palpata has become superfluous with the elevation of Canalipalpata to subclass.


Characteristics

Palpata includes the majority of genera and species of polychaete worms and is subdivided into the
orders Order, ORDER or Orders may refer to: * A socio-political or established or existing order, e.g. World order, Ancien Regime, Pax Britannica * Categorization, the process in which ideas and objects are recognized, differentiated, and understood * H ...
Aciculata Errantia is a diverse group of marine life, marine polychaete worms in the phylum Annelida. Traditionally a subclass (biology), subclass of the paraphyletic class Polychaeta, it is currently regarded as a monophyletic group within the larger Pleis ...
and
Canalipalpata Canalipalpata, also known as bristle-footed annelids or fan-head worms, is an order of polychaete worms, with 31 families in it including the suborder Sabellida (families Serpulidae (tubeworms) and Sabellidae (fanworms and feather duster worm ...
.Rouse, G. W., and K. Fauchald. 1997. Cladistics and polychaetes. Zool. Scr. 26:139-204. The
prostomium The prostomium (From Ancient Greek, meaning "before the mouth"; : prostomia; sometimes also called the "acron") is the Cephalization, cephalized first body segment in an annelid worm's body at the anterior end. It is in front of (but does not in ...
is characterised by a pair of sensory
palp Pedipalps (commonly shortened to palps or palpi) are the secondary pair of forward appendages among chelicerates – a group of arthropods including spiders, scorpions, horseshoe crabs, and sea spiders. The pedipalps are lateral to the chelicera ...
s which gives the subclass its name and which are lacking in the other main
taxon In biology, a taxon (back-formation from ''taxonomy''; : taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular name and ...
of polychaetes, the
Scolecida Scolecida is an Infraclass (biology), infraclass of polychaete worms. Scolecids are mostly unselective Detritivore, deposit feeders on marine detritus. Characteristics Scolecids have Parapodium, parapodia with rami that are all alike. The pros ...
. Aciculata is a large group including about half of all existing polychaete species and is equivalent to the old taxonomic group "Errantia", worms that can move about freely by crawling or swimming. These worms are characterised by having internal supporting
chaeta A chaeta or cheta (; ) is a chitinous bristle or seta found on annelid worms, although the term is also frequently used to describe similar structures in other invertebrates such as arthropods. Polychaete annelids (''polychaeta'' literally me ...
e in their
parapodia In invertebrates, the term parapodium ( Gr. ''para'', beyond or beside + ''podia'', feet; : parapodia) refers to lateral outgrowths or protrusions from the body. Parapodia are predominantly found in annelids, where they are paired, unjointed late ...
. Aciculata is divided into suborders
Eunicida Eunicida is an order of polychaete worms. Characteristics Members of this order have an elongated, segmented body and a distinct head, normally with a separate peristomium and prostomium. Many, but not all, live in tubes which vary from a mucou ...
and
Phyllodocida Phyllodocida is an order of polychaete worms in the subclass Aciculata. These worms are mostly marine, though some are found in brackish water. Most are active benthic creatures, moving over the surface or burrowing in sediments, or living in cr ...
. Canalipalpata is equivalent to the old taxonomic group "Sedentaria", worms that stay in one place, living in a self-made tube composed of mud or sand cemented together with mucus. Members of Canalipalpata are worms with elongated grooved palp structures used for feeding and the order is divided into suborders
Sabellida Sabellida is an order of annelid worms in the class Polychaeta. They are filter feeders with no buccal organ. The prostomium is fused with the peristomium and bears a ring of feathery feeding tentacles. They live in parchment-like tubes made o ...
,
Spionida Spionida is an order (biology), order of marine polychaete worms in the infraclass Canalipalpata. Spionids are cosmopolitan and live in soft substrates in the Littoral zone, littoral or neritic zones. Characteristics Spionids have a single pair ...
and
Terebellida Terebellida make up an Order (biology), order of the Polychaete, Polychaeta class (biology), class, commonly referred to as "bristle worms". Together with the Sabellida, the Spionida and Incertae sedis, some enigmatic families of unclear Taxonomy ...
.


Taxonomy

Further research is likely to result in changes to the
cladistics Cladistics ( ; from Ancient Greek 'branch') is an approach to Taxonomy (biology), biological classification in which organisms are categorized in groups ("clades") based on hypotheses of most recent common ancestry. The evidence for hypothesiz ...
of the annelids, the
monophyly In biological cladistics for the classification of organisms, monophyly is the condition of a taxonomic grouping being a clade – that is, a grouping of organisms which meets these criteria: # the grouping contains its own most recent comm ...
of which is in doubt. The World Register of Marine Species considers Palpata a "nomen dubium" and divides the polychaetes into three subclasses, Aciculata, Canalipalpata and
Scolecida Scolecida is an Infraclass (biology), infraclass of polychaete worms. Scolecids are mostly unselective Detritivore, deposit feeders on marine detritus. Characteristics Scolecids have Parapodium, parapodia with rami that are all alike. The pros ...
.World Register of Marine Species
/ref>


References

{{Taxonbar, from=Q3361682 Polychaetes Obsolete animal taxa