spines. P4 B2 surface nude or with thin 



setules 27. S. brevicaudatus 



Pi Re3 posterior surface with spines. P2 Bl 

 surface with strong spines. P3 Re2 posterior 

 surface with row of denticles distal from row 

 of strong spines. P4 B2 surface with spin- 

 ules 43. S. terranouae, new species 



13. Mxp Bl without transverse spine-comb. 



(Male unknown.) 9. S. spinosus 



Mxp Bl with transverse spine-comb . . . (14) 



14. Mx2 posterior surface of lobe-5 base with 



spines. (Male unknown.) . . 37. S. usitatus 

 Mx2 posterior surface of lobe-5 base without 

 spines (15) 



15. Mxp Bl transverse spine-comb on conspicu- 



ous protuberance. (Male unknown.) . . . 



38. S. hoplites 



Mxp Bl transverse spine-comb not on con- 

 spicuous protuberance (16) 



16. Length greater than 1.7 mm. Prosome elon- 



gate ovoid 10. S. horridus 



Length less than 1.7 mm. Prosome robust o- 



void. (Male unknown.) 



40. S. oUgospinosus 



17. Female: Al reaching at least to anal segment. 



Mxp Ri4-5 outer 2 setae asymmetrically 

 plumose and as large and strong as other 

 large terminal setae. P2 Re2-3 posterior sur- 

 face with 1 row of spines. P4 Re3 posterior 

 surface nude. Male: P4 Bl with inner 



seta (19) 



Female: Al not reaching beyond genital seg- 

 ment. Mxp Ri4-5 outer 2 setae lightly plu- 

 mose, moderately fragile, thin, and rela- 

 tively short. P2 Re2-3 posterior surface 

 nude. P4 Re3 posterior surface with many 

 small spinules. Male: P4 Bl without 

 inner seta (18) 



18. Length greater than 3.3 mm. Female: Pro- 



some slightly robust ovoid. P2 Rel outer 

 spine typical. Male: Ce expanded dorso- 

 laterally, nearly covering Thl. P5 biramus 



12. S. validus 



Length less than 3.3 mm. Female: Pro- 

 some long slender ovoid. P2 Rel outer spine 

 forming strongly bent hook. Male: Ce 

 not expanded. P5 essentially uniramus (ru- 

 dimentary left Ri), very asymmetrical .... 



13. S. angusticeps 



19. Female: Prosome in dorsal view slender long 



ovoid; in lateral view with gentle, uneven 

 forward slope. Prosome length 3' 4 times 

 urosome. Male: Ce slightly expanded 

 dorsolaterally. P5 biramus . . 4. S. magnus 

 Female: prosome in dorsal view robust ovoid; 

 in lateral view with abrupt, even forward 

 slope. Prosome length 4' 4 times urosome. 

 Male: Ce not expanded. P5 uniramus, very 

 asymmetrical 5. S. antarcticus 



1. Spinocalanus abyssalis Giesbrecht, 1888 



(Figures 4-10. 148) 



Spinocalanus abyssalis Giesbrecht, 1888, p. 335. — 

 Giesbrecht, 1892, p. 209-213, pi. 13, fig. 42-48; pi. 

 36, fig. 49. —Giesbrecht and Schmeil, 1898, p. 

 31. — ?Thompson, 1903, p. 16, pi. 1, fig. 6. —van 

 Breemen, 1908 (part), p. 28-29, fig. 27d 

 (only). — Brodskv, 1950, p. 129-130, fig. 49. —Park, 

 1970, p. 481-482, fig. 13-22. — Grice, 1971, p. 278- 

 280-, fig. 3LJ. 



Spinocalanus abyssalis var. pygmaeus. — Farran and 

 Vervoort, 1951a (part), p. 2-3, fig. If, h(only). Not 

 S. abyssalis var. pygmaeus Farran, 1926. 



Spinocalanus parabyssalis Park, 1970 (part), p. 483- 

 485, fig. 34-36; male only. 



Type Specimen: Neotype, female (1.20 mm) USNM 

 142700. 



Type Locality: Central Pacific, 1,000-4,000 m. 

 Material Stlt)IED: l female (l.O mm), sample 8 

 (Table 3); 1 female (1.13 mm), sample 11; 3 females 

 (1.23, 1.25, 1.27 mm), sample 22; 1 female (0.875 mm), 

 sample 24; 2 females (0.98, 1.025 mm), sample 25; 

 1 female (0.90 mm), sample 28; 1 female (1.025 mm), 

 sample 29; 3 females (1.10, 1.23, 1.30 mm) and neo- 

 type female (1.20 mm), sample 30; 2 females (1.08, 

 1.22 mm), sample 31; 1 female (1.30 mm) and 1 male 

 (1.13 mm), sample 55. 



Description 



PI Ri with 2 inner setae; P2 Ri2 with no outer seta. 



Female.— Length (0.8?-) 0.85-1.32 mm (Figs. 4, 5). 

 Prosome in dorsal view slender ovoid; prosome length 

 greater than 2.4 times width. Head rounded in dorsal 

 view, in lateral view with flat, gentle forward slope. 

 Th4 and Th5 may be separate or partly fused, es- 

 pecially dorsolaterally; Th5 lateral corners rounded, 

 not prolonged; Thl-Th4 without lateral spinules. 

 Prosome length slightly more than 3 times urosome. 

 Genital segment slightly longer than wide, protruding 

 ventrally one-half depth of rest of urosome; caudal 

 rami length nearly 2 times width, symmetrical. 

 Caudal setae incomplete on all specimens examined, 

 bases symmetrical. Supra-anal plate with fringe of 

 long hairs. 



Al exceeding caudal rami by about 4 segments; ter- 

 minal segments (Fig. 148) of moderate length and 

 width. Apparent deviation: L2s; remainder as Table 

 4. 



A2 Rel with 1 seta [Giesbrecht (1892) reported 2 

 setae]. 



Mn with row of setules on distal anterior surface of 

 B2 and on surface of Ril. Blade with 4 strong, evenly 

 spaced ventral teeth, 4 smaller closer spaced dorsal 

 teeth, and dorsal seta. 



17 



