(No common name)

ORDER

Hoplonemertea

FAMILY

Prosorhochmidae

TAXONOMY

Planaria dorsalis Abildgaard, 1806, Denmark.

OTHER COMMON NAMES

None known.

PHYSICAL CHARACTERISTICS

Small, rather stout, up to 1.2 in (30 mm); most specimens 0.4–0.6 in (10–15 mm) long and 0.04–0.07 in (1–2 mm) wide. Head bluntlyrounded, not demarcated from body, with four eyes. Extremely variable incolor; more or lessuniform brown toreddish brown withmid-dorsal whitestripe, or with irregular light or dark brown speckles varying in size and shape between specimens. Some specimens have yellowish dots, some specimens are cream without pigmentation, others with regular dark bands on light background. Ventral surface usually paler than dorsal.

DISTRIBUTION

Widely distributed in the northern hemisphere; found in the Baltic Sea, the North Sea, the Mediterranean, on eastern Atlantic coasts from northern Europe to Madeira, and both Atlantic and Pacific coasts of North America down to Mexico.

HABITAT

Marine, littoral and sublittorally, down to 260 ft (80 m). Generally associated with small algae, especially species of Ceramium and Corallina.

BEHAVIOR

Lives among algae. No other details known.

FEEDING ECOLOGY AND DIET

Not known in detail, but probably small crustaceans and other worms.

REPRODUCTIVE BIOLOGY

Dioecious, external fertilization.

CONSERVATION STATUS

Not listed by the IUCN. Common.

SIGNIFICANCE TO HUMANS

None.