NO. 3586 CYCLOPOID COPEPODS — HUMES AND HO 15 



Rhynchomolgus corallophilus, new species 



Figures 80-115 



Type material. — 45 99, 32 small cf cf , and 47 large cf cf from the 

 coral Psammocora contigua (Esper) in a depth of 1 m, southeast of 

 Ambariobe, near Nosy Be, Madagascar. Collected Sept. 6, 1963. 

 Holotype female, allotype large male, and 58 para types (20 99, 15 

 small cf cf , and 23 large cf cf ) deposited in the United States National 

 Museum, Washington; 21 paratypes (7 99, 7 small cf cf, and 7 large 

 cf cf ) in the Zoologisch Museum, Amsterdam; and the remaining 

 paratypes m the collection of A. G. Himies. 



Other specimens (all from Psammocora contigua in 1-2 m at 

 Ambariobe, collected during 1963). — 16 99, 19 small cf cT, and 25 

 large cf cf , Sept. 8; 5 small cf cf and 9 large cf cf , Sept. 17. 



Female. — Body (figs. 80, 81) with cephalosome greatly expanded 

 laterally; segments of metasome and urosome relatively slender and 

 somewhat contractile, the postgenital segments sometimes telescoped. 

 Length (not mcludmg setae on caudal rami) 1.07 mm (0.89-1.24 mm) 

 and greatest width 0.56 mm (0.49-0.63 mm), based on 10 specimens 

 in average state of contraction. Two fully extended females 1.49 x 

 0.54 mm. Ratio of length to width of prosome (not including rostrum) 

 1.29:1. Segment of leg 1 fused with head, the only indication of 

 separation bemg an mdistinct transverse dorsal fold. 



Segment of leg 5 (fig. 82) 91m x 166^- Genital segment wider than 

 long, 130/x X 161jLi, subrectangular in dorsal outlme. Areas of attach- 

 ment of egg sacs situated dorsolaterally, each area (fig. 83) bearing 

 medially two spiniform setae, both about 19/x in length and directed 

 posteriorly. Three postgenital segments 86m x 109m, 65m x 86m, and 

 60m X 75m from anterior to posterior. Last segment with a lobate 

 dorsal flap over anal area; at either side of this flap on both dorsal and 

 ventral surfaces a patch of denticles. (Enth-e urosome in telescoped 

 specimen shown in figure 3 about 325m in length, but if expanded the 

 length would reach about 475m.) 



Caudal ramus (fig. 84) 44m x 23m, with ratio of length to v/idth 

 1.91 : 1. Six short naked setae near distal end of ramus, the longest 

 about 36m. (Of these setae, one more dorsally placed than others, one 

 on outer corner, and two median, shown partly retracted in figm'e, 

 corresponding respectively to dorsal pedicellate seta, outer lateral seta, 

 and two long median terminal setae seen in less modified lichomolgids 

 such as Lichomolgus.) Ramus with a few minute spinules, small 

 setules, and refractile points as shown in figure. 



Dorsal surface of prosome with scattered refractile points and 

 setules in metasomal region (as in figs. 80, 81); urosome with dorsal 

 and ventral surfaces similarly ornamented (see fig. 82). Ratio of 



