Scolecida is an infraclass of polychaete worms. Scolecids are mostly unselective Detritivore on marine detritus.
Characteristics
Scolecids have
Parapodium with rami that are all alike.
The
prostomium is distinct. The head has no
or
and is usually conical, though in the
Scalibregmatidae, it has a T-shaped tip, and in
Paraonidae, there is a single, central antenna. In some families there are sometimes some tiny eyespots. The oesophagus is evertable forming a sac-like proboscis which may have several finger-like lobes. The anterior segments and their appendages are all similar. The notopodia and neuropodia consist of unbranched capillary
, sometimes with hooks. There is a single central gill in
Cossuridae on an anterior segment and simple segmental gills are present in some other families.
[ Annelida.net]
Systematics
The families Arenicolidae, Capitellidae and Maldanidae were formerly part of the order Capitellida. They are now included in infraclass Scolecida along with Cossuridae, Orbiniidae, Opheliidae, Paraonidae and Scalibregmatidae. This
clade is probably not a natural grouping and is likely to be revised in the future.
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Subdivisions
