347 



the 6th segment additionally bears a few short setae; the posterior distal 

 angle of the 5th segment is produced into a small triangular denticle that 

 is more prominently developed in pereopods III; the almost straight claw 

 is 1/3-1/4 the length of the 6th segment. Pereopods V-VII are similar 

 but the 2nd segment of pereopods VII is somewhat broader than in the 

 preceding ones and its posterior margin more convex; the strong claw is 

 half the length of the 6th segment. 



Epimeron I is oyal and has a keel on the distal surface; epimerons II 

 and III are more or less triangular, with an acute posterior angle. The 

 uropods have narrowly lanceolate rami with finely denticulate margins. 

 The peduncle of uropods III is approximately twice longer than the tel- 

 son. The telson is triangular, with a round or acute apex, and 1/3 the 

 length of the basipodite of uropods III. 



Female: The body is broader and more thickset than in males. Anten- 

 nae I are shorter than the head; the flagellum consists of two segments (in 

 antennae II, only one segment). Pereopods I and II are much stronger; 

 the 2nd segment is broad; the lobe of the 5th segment is broader than in 

 males, slightly curved, and in both pairs extends to the distal end of the 

 6th segment or exceeds it in length. All the uropods, especially pair III, 

 are much broader than in males. 



Notes: In the seas of the North Atlantic this species parasitizes the 

 ctenophoran Pleurobrachia pileus (Evans and Sheader, 1972) and possi- 

 bly some coelenterates. 



Distribution: A bipolar species, found in the Central Polar Basin, in 

 the North Atlantic where it penetrates southward to La-Mancha, western 

 Ireland, and Labrador; in the North Pacific it has been found in the 

 Bering, Okhotsk, and Japan seas, the Kuril-Kamchatka region, and the 

 coastal regions of Alaska. In the Southern Hemisphere it was found in 

 the South Georgia Islands, the cold coastal waters of southwest Africa 

 south of 25° S lat., and off the southern tip of New Zealand. 



It is a surfacial species. 



2. Hyperoche mediterranea Senna, 1908 (Fig. 143) 



Senna, 1908: 159; Hurley, 1955: 147. 



Length of the known specimens 3-5 mm. 



In males antennae I and the much longer antennae II distinctly 

 exceed the body length. In females the one-segmented flagellum of 

 antennae I exceeds by 1/3 the length of the peduncle; the flagellum of 

 antennae II is the same length. 



The mandibles have a thin palp, longer than the mandibular body in 

 males, much shorter in females; the dentate process is small, narrowly 

 triangular, and covered with setae. The outer lobes of the maxillipeds 

 are lanceolate, with an acute apex and slightly concave outer margins. 



