(Fig. 23A)
Spirontocaris bispinosa Holmes, 1900: 207. — Rathbun 1904: 68, fig. 23. — Schmitt 1921: 54, fig. 30. [Not Hippolyte bispinosa De Haan, 1841; = Sicyonia bispinosa (De Haan, 1849); Sicyoniidae].
Spirontocaris holmesi Holthuis, 1947: 38. — Kozloff 1974: 166. — Word & Charwat 1976 b: 149. — Hayashi 1977: 158. — Butler 1980: 165, pl. 6E. — Wicksten 1984b: 135; 1989b: 313; 1990b: 590.— Chace 1997: 56.
Diagnosis. Rostrum moderately deep, with distal styliform process bearing one subapical ventral tooth, 8–16 dorsal, 3–7 ventral teeth, 2 on carapace proper. Each segment of antennular peduncle with dorsal spine, stylocerite reaching second segment. Carapace with 2 supraorbital teeth. Pereopods 1, 2 with epipods. Pereopods 3–5 long, slender; with long, simple dactyls, 0.5–0.6 times length of propodi. Merus of pereopod 3, with 6–7 spines; pereopod 4, with 5–8 spines; pereopod 5, with 4 or 5 spines. Pleura of abdominal somites 1–4 rounded, of 5 with small point. Telson with 3 or 4 pairs dorsolateral spines, apex rounded. Male total length to 44 m, female to 62 mm.
Color in life. Body yellowish, with lines, bars, dots, patches of red (Butler 1980).
Habitat and depth. Mud or sand, 24–485 m. Specimens from California usually taken at 150–300 m.
Range. Yes Bay, Alaska to San Diego, California. Type locality Puget Sound.