198 U.S. NATIONAL MUSEUM BULLETIN 23 6 



somites 2 to 4 almost of equal length, epimeral plates moderately- 

 developed, cut off squarely. No spinules or hairs on thoracic somites. 

 Thoracic somite 5 scarcely visible dorsally, but laterally a prominent 

 feature, with several rows of exceedingly fme spinules on sides. 

 Abdominal somites 1 and 2 fused to form genital somite; line of 

 separation distinct on lateral and dorsal surfaces. Abdominal somites 



3 and 4 have equal length, each shorter than somite 1 or 2. Somites 

 1 to 3 finely haired, hah-like spinules more or less arranged in trans- 

 verse rows. In addition, there is a completely closed row of spinules 

 along the distal edge of abdominal somites 2 to 4. Anal somite 

 shorter than somite 4, anal plate distinct, nude. Insertion of furcal 

 rami bordered by fine spinules. 



Furcal rami short, twice as wide as long, structure as in A. minutus; 

 setae 2 and 3 are lengthened and thickened but not swollen basally. 

 Some dispersed spinules occur along internal and external furcal 

 borders. 



Antennules shorter than length of cephalic somite, 8-segmented; 

 segments 2 and 4 fairly long; setation represented in figure 74e. Aeste- 

 tasc found on conical process of 4th segment, accompanied by 2 fine 

 setae. 



Antenna as in A. minutus; exopodite 3-segmented, with 1, 1, and 



4 setae, respectively. 



Oral appendages as in A. minutus. 



Leg 1 (fig. 74a) with single strong spine on basis. 1st endopodal 

 segment much longer than exopodite, 8 times as long as wide. 2nd 

 endopodal segment small; 3rd endopodal segment 3 times as long 

 as wide. Segment 2 of exopodite very slightly lengthened, with small 

 internal seta; segment 3 of exopodite with total of 5 setae. 



Legs 2 to 4 as in ^. minutus; endopodites of legs 2 and 3 only slightly 

 shorter than exopodites (figs. 746,rf). Setal formula: 



endopodite exopodite 



leg 2 1.2.121 1.1.223 



leg 3 1.2.321 1.1.223 



leg 4 1.1.221 1.1.323 



Leg 5 (fig. 736) with slender exopodite, but since it is figured from 

 an oblique position, its actual shape is more cordate, fastened to the 

 baso-endopodite by means of a narrow strip, consequently narrowing 

 considerably proximally. 6 marginal setae: 3 externally, 1 at apex, 

 and 2 internally; distal part of external border spinulose. Tip of 

 baso-endopodite reaches middle of exopodite; 5 spiniform setae: 3 

 at internal margin, 2 at apex. External lobe short, with fine seta. 



Color completely faded, transparently yellowish. Female carries 

 sac composed of 3 eggs. 



Adult male, total length 0.29 mm. 



