PHYLOGENY OF ARIETELLID COPEPODS 



119 



segment not reduced, fifth segment with 2 developed setae. 



Maxillule (Fig. 8A,B): praecoxal arthrite carrying 5 serrate 

 spines and 1 process, with numerous spinules of variable sizes 

 on both sides and patch of setules; coxal endite with long, 

 serrate seta; coxal epipodite bearing 6 setae. 



Maxilla: first and second syncoxal endites (Fig. 8C) having 

 2 setae and vestigial element, and 2 spinulose setae, respec- 

 tively; basal spine (Fig. 8D) with 3 rows of spinules at 

 midlength. 



Maxilliped (Fig. 8E): fourth and fifth endopod segments 

 each with non-reduced innermost seta, sixth segment with 

 setae a and b well developed. 



Leg 1 (Fig. 8F): coxa with plumose seta at inner angle and 

 tuft of long setules near outer proximal margin; basis with 

 outer and inner plumose seta; endopod 3-segmented, all 

 segments with outer distal angle produced distally; exopod 

 3-segmented, first segment with outer setiform spine reaching 

 to distal end of second, third segment with 2 outer lateral 

 spines and 1 spiniform terminal seta. Legs 2 (Fig. 8G) and 3 

 with the same segmentation and setation; basal inner corner 

 rounded; outer process on second endopod segment (Fig. 81) 

 with minute spinules along inner margin; terminal outer 

 process on first and second exopod segments (Fig. 8H) also 

 carrying small projections midway along inner margin. Leg 4: 

 coxa unarmed; basis with outer seta on posterior surface; 

 endopod 3-segmented, setal formula 0-l;0-2;2,2,3; exopod 

 distal 2 segments missing, first segment with outer spine and 

 inner seta. 



Leg 5 (Fig. 8J): coxae incompletely fused with intercoxal 

 sclerite; basis separate from coxa, bearing outer plumose seta 

 at midlength. Right leg lacking endopod; exopod missing 

 distal segment(s), at least, 2-segmented, first segment with 

 spinulose spine and pointed process at distal angle. Left leg 

 with indistinctly 2-segmented endopod, first segment large, 

 second hemispherical with minute prominence terminally; 

 exopod 3-segmented, first segment with spinulose spine and 

 pointed process on distal corner, second segment expanded, 

 carrying outer spinulose spine at midlength, third segment 

 small, tapering distally, with 1 minute basal element, 2 short 

 medial setae along outer margin and terminal spine as long as 

 second segment. 



Remarks. Since the third leg of Crassarietellus sp. has 3 

 outer spines on the third exopodal segment and 1 inner seta 

 on the first exopodal segment, as most other arietellids, the 

 third legs of the paratypes of C. huysi are here interpreted as 

 abnormal. 



Genus Campaneria gen. nov. 



Diagnosis. Only male known. Cephalosome and first pedi- 

 gerous somite separate. Anal somite almost telescoped into 

 preceding somite; anal operculum not developed. Caudal 

 rami symmetrical, longer than wide, with vestigial seta I, 

 well-developed setae II— VI and minute seta VII. 



Left antennule reaching almost to end of urosome, genicu- 

 late, 20-segmented; segments II to IV almost fused but 

 sutures clearly visible, segments II and III each bearing seta 

 and aesthetasc; segment XIII with seta, aesthetasc and pro- 

 cess representing modified seta; segment XXI separate from 

 XXII; segment XXV incompletely fused with XXVI; seg- 

 ment XIII with seta and process; compound segment 

 XXVI-XXVIII with 8 setae and aesthetasc; segment II 



(probably, originally from I) to XIII fringed with setules 

 posteriorly. 



Antenna: first endopod segment having inner seta, second 

 segment bearing 3 inner setae subterminally and 5 setae 

 terminally; exopod indistinctly 8-segmented. Mandibular 

 gnathobase with tuft of setules. Mandibular palp: endopod 

 rudimentary, 1-segmented, with 2 setae; seta on first exopod 

 segment not reduced; outer seta on fifth exopod segment 

 relatively long. 



Maxillule: praecoxal arthrite carrying 5 spines, 3 of which 

 weakly serrate medially, and process; coxal endite with long 

 seta; coxal epipodite with 6 setae; second basal endite repre- 

 sented by vestigial seta; endopod bulbous, 1-segmented, 

 having 2 setae. 



Maxilla: first syncoxal endite with 2 setae and vestigial 

 element; second syncoxal endite with 2 setae; basal endite 

 bearing stout spine with 3 rows of spinules proximally. 



Maxilliped: setal formula of endopod 1,4,4,3,3,4; fourth 

 endopod segment with non-reduced innermost seta, fifth 

 segment with shorter innermost seta than fourth, sixth seg- 

 ment with seta a vestigial and seta b relatively long. 



Leg 1 with 2 outer spines on third exopod segment. Leg 4 

 lacking inner coxal seta. Leg 5 with coxae and intercoxal 

 sclerite fused to form a common plate; coxa separate from 

 basis. Right leg: endopod 1-segmented, bulbous; exopod 

 indistinctly 3-segmented, distal 2 segments almost fused, 

 expanded medially, with rounded process medially and 2 

 setules and 1 prominence terminally. Left leg: endopod 

 indistinctly 2-segmented, unarmed; exopod 2-segmented, dis- 

 tal segment curved outwards near tip, with 3 setae terminally 

 and 1 seta medially. 



Type species. Campaneria latipes gen. et sp. nov. 



Remarks. As already suggested by Bradford (1969), we 

 conclude that the single paratypic male of Scutogerulus 

 pelophilus belongs to a different species from the female. 



Although sexual dimorphism in mouthparts is exhibited in 

 arietellids such as Arietellus (present study) and Paraugapti- 

 lus (Deevey, 1973; present study), the sexual differences are 

 restricted to the antennary rami and the first mandibular 

 exopod segment. However, the male differs from the holo- 

 type female of S. pelophilus in armature elements on the 

 mouthparts and leg 1 as follows: (1) the female has 'shield- 

 shaped' appendages (= ornamentation) (Bradford, 1969) on 

 terminal setae of the maxilla and maxilliped, while the male 

 lacks such ornamentation; (2) there is single inner seta on the 

 first antennary endopod segment in the male but none in the 

 female; (3) the praecoxal arthrite of maxillule has 6 elements 

 in the male (5 spines and 1 process) and 5 in female (4 spines 

 and 1 process); (4) the maxillulary endopod has 2 setae in the 

 male and 1 in the female; (5) the first and second praecoxal 

 endites of the maxilla bear 2 setae plus a vestigial element and 

 2 setae in the male, and 1 seta plus a vestigial element and 1 

 seta in the female, respectively; (6) seta b on the sixth 

 endopod segment of maxilliped is long in the male but short 

 in the female; (7) the third exopod segment of leg 1 has 2 

 outer spines in the male but only 1 in the female. As far as the 

 armature is concerned, the female shows more apomorphic 

 character states than the male. In particular, the magnitude 

 of the differences in the antenna, maxilla, maxilliped and leg 

 1 is greater than not only variation within a species but also 

 normal interspecific discrepancies between congeners. A new 

 genus is, therefore, established to accommodate the male. 



