524 



the endopodite are finely serrate on the outer side and smooth on the 

 inner side. The margins of the exopodite in both sexes have simple 

 denticles. The short basipodite of uropods III is fused with the longer 

 endopodite and the reduced exopodite in the form of a small stiff spine; 

 the endopodite is denticualte on both sides and its tip does not reach 

 the tip of the telson. The telson is elongated-triangular, has an extended 

 pointed tip, and is 2.5-3 times longer than its width at the base. 



The oostegites are narrow, poorly developed; the gills, contrarily, 

 are broad and without doubt supplement the function of the oostegites 

 in the formation of the brood chamber. 



Distribution: Found in all oceans from 46° N up to 41° S. It is most 

 common in the Indo-West Pacific region and absent along the western coast 

 of Africa and in the Mediterranean and Red seas; it is fairly eurybiotic but 

 not found at temperatures below 18.5° C and with a salinity above 37%. 



4. Genus Calamorhynchus Streets, 1878 



Streets, 1878: 285; Bovallius, 1890: 72; Stebbing, 1888: 1599; Spandl, 

 1927: 197; Bowman and Gruner, 1973: 50. 



The body is elongate. The head is very large, 1/3 the total body 

 length, and slightly constricted at the base in the form of a neck; the 

 dorsal part of the head has a longitudinal medial keel; the rostrum con- 

 stitutes half the total length of the head, with broad lateral and low 

 ventromedial keels. 



The pereon is approximately the same length as the pleon. Pere- 

 opods I and II have well-developed subchelae and the distal margin of 

 the 5th segment is obliquely truncate, with an extended posterior angle. 

 Pereopods VII are seven-segmented; the 2nd segment is broad and not 

 smaller than in pereopods V-VI, being equal to or slightly longer than the 

 distal part of the leg. The coxal plates are fused with the somites of the 

 pereon. The urosome is relatively long, nearly 1/4 the total body length, 

 and longer than the pleon. The last (geminate) urosomite is fairly long: its 

 length is approximately three times its width, but if considered from the 

 place of articulation of uropods II, urosomite II is very short, uropods I 

 and II have free rami. The endopodite of uropods HI is fused with the 

 basipodite. The telson is elongated-triangular and has a pointed tip. 



Type species: Calamorhynchus pellucidus Streets, 1878. 



The genus is monotypic. 



1. Calamorhynchus pellucidus Streets, 1878 (Fig. 227) 



Streets, 1878: 285; BovaUius, 1890: 73; Spandl, 1927: 198: Pir- 



lot, 1938: 371; Shoemaker, 1945a: 251; Fage, 1960: 31; Pillai, 1966: 



m.~rigidus Stebbing, 1888: 1600; Stephensen, 1925a: 189. 



Length of sexually mature females up to 22.5 mm, of males up to 



18.5 mm. 



