Distribution 



Accepted records of S. spinosus are: 



Pacific Ocean 



Central: Present study, 0-1,000 m. 

 Atlantic Ocean 



Northeast: Farran (1908, 1920, 1926), 180-1,800 

 m. 



Caribbean Sea: Park (1970), 505-1,000 m. 



Probable records, at least in part, of S. spinosus are: 

 Grice (1963), Grice and Hulsemann (1965), Wheeler 

 (1970), and Roe (1972b) in the North Atlantic; and De 

 Decker and Mombeck (1965) and Grice and 

 Hulsemann (1967) in the Indian Ocean. 



Some of Farran's specimens of S. spinosus are in the 

 collection of the National Museum of Ireland, Dublin 

 (O'Riordan, 1969). 



10. Spinocalanus horridus 

 Wolfenden, 1911 



(Figures 69-83, 153) 



Spinocalanus horridus Wolfenden, 1911, p. 216, fig. 7; 



pi. 25, fig. 1-2. —Park, 1970, p. 491, fig. 66-70. 

 Spinocalanus abyssalis. — Tanaka, 1937 (part), p. 



253-254, fig. 4a-c; female only. — Minoda, 1971 



(part), p. 11, fig. 30(3), 32(1), 33(2); 1.95-2.2 mm 



only. Not S. abyssalis Giesbrecht, 1888. 

 Spinocalanus stellatus Brodsky, 1950, p. 125-126, fig 



44. —von Vaupel-Klein, 1970, p. 8-10, fig. Ib-f. 

 Spinocalanus spinipes Brodsky, 1950 (part), p. 126- 



127. fig. 45; female only. 

 Spinocalanus dorsispinosus Brodskv, 1950, p. 129, 



fig. 48. 

 Spinocalanus sp.? Brodsky, 1950 (part), p. 130-131, 



fig. 50; female only. 

 Spinocalanus lungispinus Brodsky, 1950, p. 131, fig. 



51. — Vidal, 1971, p. 18, 23-24, fig. 42-45, 58-59. 

 Spinocalanus spinosus. — Tanaka, 1956, p. 390-391, 



fig. 14. Not S. spinosus Farran, 1908. 



Type SPECIMEN: Unknown. 

 Type Locality: South Atlantic, 0-1,200 m. 

 Material Studied: 3 females (2.23-2.30 mm), sam- 

 ple 38 (Table 3); 2 females (2.10, 2.12 mm), sample 

 58; 1 female (2.12 mm), sample 59; 1 female (2.28 

 mm) and 1 male (2.10 mm), sample A2 (Table 1); 1 

 male (2.1 mm) and 1 male stage V (1.95 mm), sample 

 A4; 2 males (2.18, 2.25 mm), sample A5; 1 male stage 

 V (1.97 mm), sample A6; 1 male (2.28 mm), sample 

 A21; 2 females (2.48, 2.52 mm) and 1 male (2.32 mm), 

 sample A23; 4 females (2.28-2.48 mm, mean = 2.36 

 mm), sample A24; 1 male (2.24 mm), sample A33; 1 

 female (2.36 mm), sample A40; 1 female (2.36 mm), 

 sample A41; 1 female (2.32 mm), sample A42; 1 



female (2.36 mm), sample A45; 2 females (2.32, 2.58 

 mm) and 1 male (2.24 mm), sample A48. 



Description 



Pi Ri with 2 inner setae; P2 Ri2 with 1 outer seta. 



Female.— Length 1.95-3.0 mm (Figs. 69, 70). 

 Prosome in dorsal view slightly robust, elongate 

 ovoid; head rounded with slight anterior 

 protuberance. Prosome in lateral view with irregular, 

 gentle forward slope. Th4 and Th5 separate; Th5 

 lateral corners rounded, not prolonged. Thl-Th4 with 

 lateral spinules, number decreasing posteriorly; right 

 side sometimes completely devoid of spinules (Arctic 

 specimens), or spinule distribution may be ap- 

 proximately even right and left (Caribbean 

 specimens). Prosome length 2% times urosome. 

 Genital segment somewhat longer than wide, 

 protruding ventrally about one-half depth of rest of 

 urosome; hairs on ventral surface of genital segment 

 and probably urosome segment 2. Caudal rami length 

 I'j times width, symmetrical. 



Al exceeding caudal rami by 1-2 segments; ter- 

 minal segments (Fig. 153) slightly elongate. Appar- 

 ent deviation: I-2s; remainder as Table 4. 



A2 Rel with 2 setae. 



Mn palp with central and distal cluster of long 

 setules on anterior surface; Ril surface with setules. 



Mxl gnathobase (Fig. 71) with cluster of spines and 

 4 setae on proximal posterior surface; distal anterior 

 surface with thin spinule; small cluster of setules near 

 distal outer margin. 



Mx2 (Fig. 72) with small setule-covered hump on 

 proximal outer edge; outer seta present; posterior sur- 

 face of lobe-5 base without spines. Lobe-4 distal 

 posterior seta stout, with row of close-set spines (Fig. 

 72 showing only alternate spines). Lobe-5 distal 

 posterior seta spinulose, with slightly widened open- 

 ing at tip of seta. 



Mxp (Fig. 73) Bl with strong transverse spine-comb 

 on outer midmargin; irregular oblique rows of spines 

 on central and distal anterior surface. One specimen 

 with spine-comb only on left Bl. B2 with strong 

 transverse spine-comb about one-third length on out- 

 er margin; longitudinal row of spinules on inner 

 margin. Ril and Ri5 with inner row of thin spinules. 

 Ri4-5 outer setae nude, bladelike, tapering toward 

 each end. 



PI (Fig. 74) Bl-2 surface with setules and hairs, in- 

 ner margin with hairs. Rel-2 outer distal anterior sur- 

 face with row of spinules. Posterior surface of Re3 with 

 5-6 spines. Ri inner anterior surface with row of thin 

 spinules about midlength. 



P2 (Fig. 75) Bl outer surface with 3-4 rows of 

 setules; hairs and setules on inner margin. P3 (Fig. 76) 

 Bl surface with 1 inner and 3-4 outer rows of spines; 

 inner margin with hairs. P4 (Fig. 77) Bl inner surface 

 with several patches of long setules, outer surface with 



37 



