144 



S. OHTSUKA, G.A. BOXSHALL AND H.S.J. ROE 



A,B,D-F,H 



Fig. 26. Metacalanus sp. 1, female (A-F), male (G); Metacalanus sp. 2, female (H). A. Fourth endopod segment of maxilliped, innermost 

 seta indicated by arrowhead; B, Fifth endopod segment of maxilliped, innermost seta indicated by arrowhead; C, Sixth endopod segment of 

 maxilliped; D, Exopod of leg 1, anterior surface; E, Right leg 5, posterior surface; F, Left leg 5, anterior surface; G, Leg 5, anterior 

 surface; H, Leg 5, posterior surface. Scales in mm. 



pedigerous somite; last pedigerous somite with short promi- 

 nence or curved process dorsally and weakly developed lobe 

 laterally on each side. Genital double-somite with pair of 

 gonopores located anteroventrally; copulatory pores asym- 

 metrically distributed posteroventrally, each copulatory duct 

 heavily chitinized; seminal receptacle relatively small. Caudal 

 rami symmetrical, longer than wide, with setae II and III 

 normally developed. 



Antennule symmetrical or slightly asymmetrical in orna- 

 mentation of terminal segments (outer seta on segments 

 XXV and XXVI with thicker setules in one antennule than in 

 other) and in length, left slightly longer than right, 

 20-segmented; segments I to IV fused; segments XXIII- 

 XXVIII fused; segments II, IV, VI, VIII-X, XII and XIII 



lacking aesthetasc; segment XIII with 2 setae; compound 

 segment XXVI-XXVIII with 7 setae and 1 or 2 aesthetascs. 

 Antenna: first endopod segment without inner seta, second 

 segment bearing 1 seta medially, and 5 setae and vestigial seta 

 terminally; exopod indistinctly 6-segmented, sixth segment 

 rudimentary, unarmed. Mandibular gnathobase with tuft of 

 setules; 3 teeth on cutting edge, dorsalmost of which bifid at 

 tip. Mandibular palp: endopod absent; first exopod segment 

 bearing vestigial seta, outer seta on fifth segment vestigial. 

 Maxillule: praecoxal arthrite with 5 spines; coxal endite 

 bearing no seta; coxal epipodite with 8 setae; endopod 

 absent. Maxilla: first and second praecoxal endite bearing 1 

 seta and 1 rudimentary element, and 1 seta, respectively; 

 basal spine bipinnate; endopodal setae with triangular 



