496 



has a highly rounded contour (contour of the denticles tips), with eight 

 triangular denticles. The 6th segment has four denticles on the posterior 

 margin. The 3rd and 4th segments of pereopods II on their posterior mar- 

 401 gin have only two setae; the distal process of the 5th segment is more 

 pointed than in pereopods I and the 6th segment has only three denti- 

 cles." The 2nd segment of pereopods V is oval, 1.5 times longer than 

 wide, and equal in length to the distal segments together; the 4th-6th 

 segments have denticulate margins. The 2nd segment of pereopods VI is 

 triangular but not larger than in pereopods V and its width only slightly 

 more than half its length; the anterior distal angle of the 2nd segment 

 is not strongly developed but forms a well-developed rounded process 

 armed with five low denticles; the distal segments together are shorter 

 than the 2nd segment; the 4th-6th segments have a denticulate anterior 

 margin; the 5th segment is shorter and narrower than the 4th but equal to 

 the 6th in length. The 2nd segment of pereopods VII is twice longer than 

 wide, the anterior margin almost straight, and the posterior one bulged; 

 the distal segments together are 3/4 the length of the 2nd segment; of 

 these, the 4th is the longest and the anterior margin of the 5th is armed 

 with very fine denticles. 



The last urosomite is almost 1.5 times longer than wide. The 

 basipodite of uropods I is equal to the endopodite in length; the exopodite 

 is shorter. The basipodite of uropods II is shorter than the endopodite 

 but longer than the exopodite. Uropods III are somewhat longer than the 

 telson and the rami are not broadened distally. The tip of the telson is 

 broadly rounded, its length less than the width at the base, and about 2/3 

 that of the last urosomite. 



Distribution: Known from the Atlantic Ocean (region of Bermuda 

 Islands). 



2. Genus Euthamneus Bovallius, 1890 



Bovallius, 1890: 19.— Thamneus Bovallius, 1887a: 31; Stebbing, 

 1888: 1558; Bowman and Gruner, 1973: 48. 



The body is compact and slightly flattened dorsoventrally. The head 

 is flattened and in males is anteriorly stretched into a short, broad, and 

 upwardly bent rostrum. The pereon is strongly broadened, bulged, dolio- 

 form. Antennae 11 are rudimentary in males, much shorter than the head. 

 The 2nd segment of pereopods I and II is barely broadened. The 2nd 

 segment of pereopods V-VII is slightly broadened; the distal segments 

 of pereopods V and VII are twice the length of the 2nd segment. The 

 rami of uropods I and III extend beyond the tip of the telson. 



Type species: Thamneus rostratus Bovallius, 1887. 



