Home|Search|Identify|Taxonomic tree|Quiz|About this site|Feedback
Developed by ETI BioInformatics
Characteristics, distribution and ecology
Taxonomische classification
Synonyms and common names
Literature references
Images, audio and video
Distribution map
Links to other Web sites

Dahl, 1938

Description:
Urosome segments 1 to 3 only very slightly raised dorsally, with small groups of slender dorsal spines and only an occasional small seta. Epimeral plates 2 and 3 subquadrate, posterior margin about straight with a few small setules. Head with the lateral lobes broadly rounded, post-antennal sinus deep; eyes slender and elongate kidney-shaped. Antenna 1 much longer than antenna 2, peduncle sparsely setose; accessory flagellum equal to the length of peduncle article 2, and 5 to 7-articulate. Antenna 2 peduncle and flagellum moderately setose, calceoli absent. Mandible palp article 1 devoid of setae, article 3 with one setal group on the outer surface, ventral setae comb-like, not graduated. Male gnathopod 1 propodus narrowly oval, palm weakly convex, median palmar spine well separated from the angle spines, proximal posterior margin with three or four setal groups. Male gnathopod 2 propodus much broader than in gnathopod 1 and the palm less strongly oblique, palm almost straight with the median spine well separated from the graduated row of angle spines. Female gnathopod 1 propodus oval, palm convex; gnathopod 2 propodus rectangular, palm transverse. Pereiopods 3 and 4 slender, spinose and sparsely setose. Pereiopods 5 to 7 basis with the posterodistal angle freely produced, posterior margin with several small setules; merus, carpus and propodus strongly spinose, with few setae, some setae a little longer than the associated spines. Male uropod 3 inner ramus about one-third to one-half of the length of the outer ramus, article 2 of the outer ramus absent; outer ramus with marginal and apical spines and dense setae, few of the inner-marginal setae plumose. Female uropod generally similar to the male one, except spines more elongate and setae less dense. Telson with each lobe with three apical spines and a few short setae, and three lateral spines.

Size:
Up to 20 mm in male, female smaller.

Colour:
Pale brown or yellow.

Habitat:
Intertidal, typically around mid-tide level; often found in tide pools, has a limited tolerance of reduced salinity.

Distribution:
North Atlantic, American and European coasts. Widely recorded on European coasts from north Norway and Iceland to western English Channel.

Gammarus finmarchicus