Mopalia spectabilis I. M. Cowan & G. M. Cowan 1977

Dorsal surface of wide girdle has no scales or granules but does have abundant flexible, bottle-brush-shaped hairs which are not as long as the girdle is wide. The girdle hairs are not strap-shaped, may be up to 4 mm long, have filamentous branches, and have glassy spicules on the tips. Has a cleft in the posterior end of the girdle. The lateral areas of plates 2-7 are separated from the central areas by a series of enlarged tubercles or by a ridge of enlarged, partly coalesced tubercles. The lateral areas also have a crosshatched pattern of tubercles along the margins. The central areas of the plates are pitted in longitudinal rows. The plates are olive with bright turquoise, orange, or reddish-brown zigzag marks, especially on plate 2. The first plate does not have large longitudinal ridges. The girdle is usually banded orange and brown.

How to Distinguish from Similar Species: Mopalia ciliata and M. hindsii also have the posterior cleft in the girdle, but M. ciliata has strap-shaped girdle hairs and M. hindsii has no pronounced ridge separating the c

Biology/Natural History: This species feeds on sponges, hydroids, bryozoans, and tunicates. It is often found feeding on the red social tunicate Metandrocarpa taylori. Some of these as well as tube worms may encrust its plates. A scaleworm may be in the mantle cavity. M. ferreirai may actually be part of this species.

Under rocks and ledges, often on exposed coasts

Geographical Range: Kodiak Island, Alaska to Baja California, Mexico

Depth Range: Intertidal to 10 m