417 



the medial protuberance is high and triangular; the medial denticle is 

 absent in adult females; in young individuals and adult males the medial 

 denticle is developed while the medial protuberance is lower than that in 

 females; in males the anterior distal tooth on the 5th segment is reduced: 

 its tip barely reaches the level of the distal margin. The 6th segment of 

 pereopods V in both sexes extends far beyond the anterior margin of the 

 5th segment; it is uniformly curved and in females bears a protuberance 

 in the middle of the anterior margin. 



The rami of the uropods of females are approximately equal in 

 length. The exopodite of uropods II of males is longer than the 

 endopodite. 



Distribution: Widely distributed in the tropics and subtropics of the 

 three oceans and in the Mediterranean Sea. From warm waters it enters 

 into the temperate latitudes: found south of Iceland, in the Bering Sea, 

 Gulf of Alaska, and south of New Zealand. 



2. Phronima atlantica Guerin-Meneville, 1836 (Fig. 179) 



Guerin-Meneville, 1836: 7; Bate, 1862: 318; BovalUus, 1889: 374; 

 Stebbing, 1888: 1351; Vosseler, 1901: 21; Chevreux and Fage, 1925: 395; 

 Pirlot, 1929: 112; Shoemaker, 1945a: 236; Shih, 1969: \A.—sedentaria 

 (non Forskal, 1775): Glaus, 1872: 331; Chun, 1889a: 378. 

 340 Length of adult females 12-25 mm, of males 8-11 mm. 



The antennae in males are well developed. Antennae I have a seven- 

 segmented flagellum. Antennae II are generally longer, the flagellum 1 1- 

 to 12-segmented. 



Pereopods V have an elongated 4th segment;length of the 5th seg- 

 ment in females is more than its width, in males the length is roughly 

 equal to the maximum width: the posterior proximal angle of this segment 

 in males roundly protrudes, in females without protrusion; the anterior 

 distal tooth of the 5th segment is medium in size, much shorter than the 

 segment itself, its apex approximately at the same level of the apex of 

 the medial protuberance or somewhat higher; the posterior side of the 

 medial protuberance is finely denticulate, the medial denticle is devel- 

 oped in both sexes. The 6th segment of pereopods V projects beyond the 

 anterior margin of the 5th segment (with closed subchela) by not more 

 than 1/3 its length. 



The rami of the uropods I in males are approximately equal in length, 

 in females the exopodite is slightly shorter. The exopodite of uropods II 

 is longer than the endopodite. The rami of uropods III are equal in length 

 in both sexes. 



Distribution: Dirstributed in the tropics and subtropics of the Atlantic 

 and Indian oceans, and in the Mediterranean Sea. Common in the western 

 and eastern parts of the tropical zone of the Pacific Ocean; rare in the 



