Harmothoe imbricata is a very common species in shallow waters among algae and stones.

Harmothoe imbricata showing a wide variety of colour morphs. 


Up to 6.5 cm with up to 39 segments.


Harmothoe imbricata comes in a number of colour varieties. It is the scales that are differently pigmented. The prostomium is red as in many other species of Polynoidae and have a pair of distinct peaks on its anterior edge. There are 15 pairs of scales, and the scales have small conical tubercles across its surface. In addition to these there might be larger rounded tubercles on the posterior part of the scales, but this is not always the case. 


Harmothoe imbricata is similar to a number of other species of Polynoidae. However, it can be separated from most of them by the position of the anterior eyes. Most other similar species of Polyonidae have their anterior pair of eyes on the widest (median) part of the prostomium while H. imbricata and H. antilopes have their anterior pair of eyes at the anterior-most part of the prostomium. Harmothoe antilopes may be separated from H. imbricata on its scales, where the small tubercles on its surface ends in a spiny crown, and the margin of the scales that are furnished with long papillae which is not the case in H. imbricata.  

Biology, ecology and behaviour

Harmothoe imbricata may be free-living or live as a commensal together with tube-building annelids or hermit crabs. It appears to be omnivorous. Reproduction takes place during wintertime, and the eggs are carried by the female until the larvae can swim.


Harmothoe imbricata lives among stones and algae from the intertidal zone, but may also be found on muddy sediments down to 300 meters depth.

Recommended citation

Nygren A. Harmothoe imbricata (Linnaeus, 1767). www.artsdatabanken.no/Pages/313090. Downloaded <year-month-day>.