Four-striped polycera (Polycera quadrilineata)
|Researched by||Rose Edwards||Refereed by||Admin|
|Authority||(O. F. Müller, 1776)|
|Other common names||-||Synonyms||Thecacera capitata (O. F. Müller, 1776)|
Polycera quadrilineata may grow up to 3.9 cm, but the maximum recorded length is 4.5 cm. Its body is translucent white with patches of yellow and orange pigments forming five longitudinal lines. Along the mid-line there is a row of oval blotches, merging towards the rear. Occasionally individuals have black streaks, blotches or fine spots on their backs. The front region of the head extends to form an oral veil. The edge of the foot is usually dotted with colour extended into a veil which is usually edged with yellow-orange colour with spots on the flank. The four frontal processes (frontal veil papillae) are coloured yellow. Two sensory organs (rhinophores) are present on its head, they have thick stalks which end with a yellow cylindrical knob. The eggs are spawned in a short white curved ribbon. This species is often found in large numbers.
Recorded distribution in Britain and IrelandCommon all around the British Isles.
Global distributionRecorded from America to the Mediterranean.
HabitatPolycera quadrilineata occurs on encrusting sea mats (Bryozoa) from the intertidal and sublittoral zones to depths of about 60 m.
- Grows up to 3.9 cm.
- Translucent white with patches of yellow and orange.
- Five longitudinal lines of varying shades along the back.
- Four processes on the oral veil.
Polycera quadrilineata is sometimes confused with Polycera faeroensis. However Polycera faeroensis has 8 or more oral veil processes whereas Polycera quadrilineata has four, and the patches of yellow pigments on the body are absent from Polycera quadrilineata.
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Last Updated: 17/04/2008