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Scalibregmatidae
Description
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The prostomium is truncate or T- or V-shaped. The
peristomium forms a ring which is partially subdivided into
two on the dorsal and lateral surfaces.
Antennae are absent, as are external palps, although palpal nerves are present.
Nuchal organs comprise short ciliated grooves. The longitudinal muscles are grouped
in bundles. Segmentation is distinct, the first segment being
similar to the second, with small, fully-developed parapodia.
Both rami on the parapodia are short, conical or truncate, and
dorsal and ventral cirri are lacking. Branching branchiae are
present in most taxa and are associated with the parapodia.
Multiple pygidial papillae are present or absent. Lateral
organs are present; dorsal cirrus organs have not been
observed. The pharynx is an eversible, simple axial sac
(= proboscis); there is no gular membrane and the gut forms a
simple tube. The chaetae consist of both smooth and
ornamented capillaries, furcate chaetae (in many taxa), and
spines that are present on the first chaetigers in some taxa;
there are no aciculae.
The above description is taken from Hutchings (2000), which is based upon Fauchald
& Rouse (1997).
Identification tips
Recognising the family
Scalibregmatids may be short or moderately long
worms which are distinctively rugose and annulated. The prostomium has a pair of anterolateral ‘horns’, but otherwise lacks appendages. Tufted branchiae are associated with the parapodia.
Distinguishing species
Body shape, the number of anterior achaetigerous segments, presence or absence of branchiae and the presence or absence of furcate chaetae are important distinguishing characters.
Description | Identification
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