Lepidonotus squamatus (Linnaeus, 1767)

Common name(s):  Rusty scaleworm

Synonyms: Aphrodita squamatus,  Lepidonotus caelorus Lepidonotus squamatus
Phylum Annelida 
Subclass Palpata 
Order Aciculata 
Suborder Phyllodocida 
Lepidonotus squamatus, about 10 mm long.  This individual has lost a few anterior elytra.
(Photo by: Dave Cowles, July 2009 )
Description:   As with other members of Family Polynoidae, the dorsal side of this species is covered with a series of platelike elytraLepidonotus squamatus has only 12 pairs of elytra, which is less than other local family members have.  Also, the lateral pair of prostomialantennae are inserted directly into anterior projections of the prostomium rather than ventral to the medialantenna.  The dorsal surface often is fouled with debris or marine growth.  The elytra are rough, with a complex covering of tubercles, and usually have rusty brown spots.  The posterior margins of the elytra have a dense fringe of long papillae.  Both pairs of black eyes can be seen from the dorsal side (except when covered by the elytra). Neurosetae are coarser than the notosetae, and have single-toothed tips.  Length to 2.5 cm.

How to Distinguish from Similar Species:  Other Polynoid scaleworms have more than 12 pairs of elytra (usually 15 or more).

Note: Leslie Harris (personal communication), a polychaete specialist from the Natural History Museum of Los Angeles County, says this individual does not look right to be L. squamatus, and that they also are not likely to be found along our coast. It may perhaps be L. spiculus, which does not appear in either the Kozloff key nor the Carlton key.

Geographical Range: Cosmopolitan, Atlantic and Pacific.  On our coast from Alaska to California.

Depth Range:  Low intertidal to 46 m or more.

Habitat:  Free-living in kelp holdfasts, under rocks, and among barnacles or mussels.

Biology/Natural History:   This species often curls into a ball when disturbed.  Omnivorous, feeding both on animals and on algae.  Sexually mature males are pale due to sperm within the body, while females are dark gray to green.



Dichotomous Keys:
  Carlton, 2007
  Kozloff, 1987, 1996

General References:
  O'Clair and O'Clair, 1998

Scientific Articles:

Web sites:

General Notes and Observations:  Locations, abundances, unusual behaviors:

../../Glossary/Glossary.html#ElytronHead dorsal view with elytra
This dorsal view of the anterior body shows the rough elytra (several are missing).  Note the particles of debris adhering to the elytra and elsewhere, and the brownish coloration on the elytra.

Authors and Editors of Page:
Dave Cowles (2009):  Created original page
CSS coding for page developed by Jonathan Cowles (2007)