263 



usually has a characteristic appearance: steeply curved back, small head, 

 and weak extremities. The head tapers toward the antennae, its height 

 more than its length; in males the cephalic length is equal to, in females 

 less than the length of the first two somites of the pereon. The eyes 

 in females occupy about 1/4 the lateral surface of the head, in males 

 about 1/3, dorsally broadened; the degree of pigmentation varies from 

 almost black to bright brown. Antennae I are equal in length to the head 

 and somite I of the pereon together; the base is short, the 1st segment 

 of the flagellum barely longer than the head, almost oval, anteriorly 

 rounded, with apically situated rudiment of the 2nd segment. Anten- 

 nae II are shorter than antennae I, especially in females, and five- to 

 six-segmented. 



The slightly bulged pereon is equal in length to the pleon and uro- 

 some together. Somite I is half the length of somite II; the somites 

 increase in length from I to IV, somites V and VI are barely shorter 

 than somite IV, and somite VII equal to somite III. The 2nd segment 

 of pereopods I is shorter than the rest of the leg, the margins convex, 

 particularly the anterior one, and its length approximately 1.7 times its 

 maximum width; the 4th segment projects along the posterior margin 

 of the 5th segment; a thin spine is present in the posterior distal angle 

 of the 2nd-4th segments; the 5th segment is barely longer than wide, 

 with one spine in the anterior distal angle and two-three much stronger 

 spines in the posterior distal angle; the 6th segment is longer than the 

 5th, with a highly convex anterior margin bearing three-four spinules 



217 and a straight, finely denticulate posterior margin; the distal margin of 

 the 5th-6th segments and the posterior margin of the claw are also den- 

 ticulate; the claw is about half the length of the 6th segment. The 2nd 

 segment of pereopods II is equal in length to the rest of the leg; the 

 anterior margin is straight but the posterior margin is faintly convex and 

 bears a spine in the distal part; the spoon-shaped lobe of the 4th seg- 

 ment projects along the posterior margin of the 5th segment over 3/4 

 its length; the spines along the posterior margin of the lobe are thin, 

 distally strong, with a bent apex; the process of the 5th segment reaches 

 1/2-2/3 of the next segment; the inner sides of the chela are denticulate; 

 the anterior margin of the 6th segment is convex, with three-four thin 



218 spinules; the claw is about half the length of the 6th segment. Pere- 

 opods III-IV are similar, pereopods IV slightly longer; the 2nd segment 

 is twice longer than wide; the distal margin of the 5th and posterior 

 margin of the 6th segment are finely denticulate; the claw is 1/2-1/3 the 

 length of the preceding segment. The 2nd segment of pereopods V has 

 straight margins, its length approximately 1 .5 times more than its width; 

 the anterior margin distally bears several spinules; the 5th and 4th seg- 

 ments are equal in length; the 6th segment is narrow and very long, its 



