USNS Eltanin material. 1♂ (SL 4.2 mm), stn 71, USNM.
Additional material. Albatross: paratypes, 1♂ (SL 3.5 mm), 2♀♀ ovigs (SL 2.8-3.0 mm), stn 4110, Santa Catalina Island, S. of Long Point, 320-333 m, 11 April 1904, USNM 168318; paratype, 1♂ (SL 2.1 mm), stn 4412, Santa Catalina Island, S. of Bird Rock, 477-493 m, 11 April 1904, USNM 168319; 35♂ (SL 3.6-4.1 mm), l♀ ovigs (SL 3.0 mm), stn 2935, 32°44'30"N, 117°23'W, off southern California, 223 m, 4 February 1889, USNM 216289. R/V Velero IV: 3♂ (SL 3.0-3.6 mm), 1♀ ovigs (SL 3.0 mm), stn 24471, 33°31'N, 118°42'W, off southern California, 302-348 m, 8 March 1976, AMS P.26903; 1♂ (SL 3-6 mm), l♀ ovigs (SL 3.1 mm), stn 24813, 33°57'N, 120°29'W, San Miguel Island, 4 miles SW of Point Bennett, 301-333 m, 24 April 1976, coll. M. K. Wicksten, USNM 170396.
Description (amended from De Saint Laurent, 1972). Shield weakly calcified on dorsomedial region; ventrolateral margin usually with minute spine. Rostrum with dorsal ridge. Distal margin of cornea reaching to about 2/3 of fifth antennal segment, and to about midlength of penultimate antennular segment. Antennal peduncle with flagellum reaching to tip of right cheliped, with numerous setae < 1 to 3 flagellar articles in length; fourth segment bearing small spine on dorsolateral distal angle; second segment with dorsolateral distal angle produced into strong spine (rarely bifid or multifid) reaching to approximately midlength or more of antennal acicle; acicle exceeding eye by about 1/3 to 1/2 length of acicle. Epistomial spine upwardly curved. Sternite of third maxilliped with small spine on each side of midline.
Right cheliped considerably variable in proportions depending on size, large specimens with carpus and chela much longer than broad (Fig. 8 d, f). Chela with iridescent areas (preserved specimens) on dorsal surface; lateral margin well delimited by row of sharp to blunt spines; dorsomesial margin well defined by row of small spines, menial face nearly perpendicular to dorsal face. Left cheliped with carpus weakly calcified on lateral face; palm with dorsomesial row of 4-6 small tubercles or spines.
Anterior lobe of sternite of third pereopods unarmed, subtriangular, setose. Fourth pereopod with propodal rasp bearing single row of rounded scales at least on distal (occasionally with 2 or 3 rows on proximal 1/5; Fig. 8 i). Fifth pereopod with propodal rasp subtriangular, extending to midlength of propodus.
Gills phyllobranchiate, with narrow lamellae.
Telson and uropods asymmetrical, left side largest. Left exopod of uropod elongate. Telson of males with left posterior lobe armed with 5 strong, often curved spines on distal margin (Fig. 8 m); right lobe armed and distal margin with 4 spines smaller, less strong than those on right lobe. Telson of females with posterior lobes armed with several irregular rows of small corneous spines on dorsodistal margin (in addition to spines on distal margin; Fig. 81).
Males lacking first pleopods; second pleopods asymmetrical, uniramous, each consisting of single segment (Fig. 8 n). Females lacking first pleopods; with paired asymmetrical second pleopods, left biramous (rami crossed), right vestigial.
Symbiotic associations. The single specimen from USNS Eltanin station 71 was found without housing. Specimens from the northern range of this species, however, are frequently found living in gastropod shells with an actinian attached.
Distribution. Eastern Pacific, from off southern California (including the Gulf of California), to off Valparaiso, Chile. Depth range: 55-923 m.
Remarks. Previously, this species was known only as far south as the Gulf of Panama (De Saint Laurent, 1972; Wicksten, 1987, 1989). Thus, the discovery of S. haigae off Valparaiso represents a considerable extension (over 7600 km) of its range.