794 
Fishery Bulletin 96(4), 1998 
Table 4 
Pigment occurrence at various pigment loci for grass rockfish, Sebastes rastrelliger. SL = standard length in mm. Definitions of 
pigment loci are given below. 0.0 = no pigment, 1.0 = some pigment present, and 2.0 = area heavily pigmented. LJ = anterior tip 
of the lower jaw, EYE = posterior-ventral edge of the eye orbit, HEAD = cranial surface, FACE = dorsal surface anterior to the 
eyes, OPER = operculum, CHK = radiating cheek bars, NAPE = nape pigment, DORS = dorsal body surface, VENT = ventral body 
surface, MID = along the lateral midline, HYP = hypural region, DFIN = spinous dorsal fin, AFIN = anal fin, PEC = blade of the 
pectoral fin. 
SL 
LJ 
EYE 
HEAD 
FACE 
OPER 
CHK 
NAPE 
DORS 
VENT 
MID 
HYP 
DFIN 
AFIN 
PEC 
10.0 
2.0 
0.0 
2.0 
2.0 
2.0 
0.0 
1.0 
2.0 
2.0 
1.0 
0.0 
0.0 
0.0 
0.0 
13.8 
2.0 
2.0 
2.0 
2.0 
2.0 
0.0 
1.0 
2.0 
2.0 
2.0 
1.0 
0.0 
0.0 
0.0 
16.7 
2.0 
2.0 
2.0 
2.0 
2.0 
0.0 
2.0 
2.0 
2.0 
2.0 
0.0 
0.0 
0.0 
0.0 
16.7 
2.0 
2.0 
2.0 
2.0 
2.0 
0.0 
2.0 
2.0 
2.0 
2.0 
0.0 
0.0 
0.0 
0.0 
16.8 
2.0 
2.0 
2.0 
2.0 
2.0 
0.0 
2.0 
2.0 
2.0 
2.0 
0.0 
0.0 
0.0 
0.0 
17.4 
2.0 
2.0 
2.0 
2.0 
2.0 
0.0 
2.0 
2.0 
2.0 
2.0 
0.0 
0.0 
0.0 
0.0 
17.5 
2.0 
2.0 
2.0 
2.0 
2.0 
0.0 
2.0 
2.0 
2.0 
2.0 
0.0 
0.0 
0.0 
0.0 
18.0 
2.0 
2.0 
2.0 
2.0 
2.0 
0.0 
2.0 
2.0 
2.0 
2.0 
0.0 
0.0 
0.0 
0.0 
18.3 
2.0 
2.0 
2.0 
2.0 
2.0 
0.0 
2.0 
2.0 
2.0 
2.0 
0.0 
0.0 
0.0 
0.0 
18.8 
2.0 
2.0 
2.0 
2.0 
2.0 
0.0 
2.0 
2.0 
2.0 
2.0 
0.0 
1.0 
0.0 
0.0 
19.2 
2.0 
2.0 
2.0 
2.0 
2.0 
0.0 
2.0 
2.0 
2.0 
2.0 
0.0 
0.0 
0.0 
0.0 
19.3 
2.0 
2.0 
2.0 
2.0 
2.0 
0.0 
2.0 
2.0 
2.0 
2.0 
0.0 
1.0 
0.0 
0.0 
19.7 
2.0 
2.0 
2.0 
2.0 
2.0 
0.0 
2.0 
2.0 
2.0 
2.0 
0.0 
0.0 
0.0 
0.0 
20.9 
2.0 
2.0 
2.0 
2.0 
2.0 
0.0 
2.0 
2.0 
2.0 
2.0 
1.0 
1.0 
0.0 
0.0 
21.6 
2.0 
2.0 
2.0 
2.0 
2.0 
0.0 
2.0 
2.0 
2.0 
2.0 
1.0 
2.0 
0.0 
0.0 
22.7 
2.0 
2.0 
2.0 
2.0 
2.0 
0.0 
2.0 
2.0 
2.0 
2.0 
1.0 
2.0 
0.0 
0.0 
24.3 
2.0 
2.0 
2.0 
2.0 
2.0 
0.0 
2.0 
2.0 
2.0 
2.0 
1.0 
2.0 
0.0 
0.0 
27.7 
2.0 
2.0 
2.0 
2.0 
2.0 
0.0 
2.0 
2.0 
2.0 
2.0 
2.0 
2.0 
1.0 
0.0 
first appeared in the otoliths of the 20.9-mm speci- 
men and was subsequently observed in the otoliths 
of all specimens larger than 20.9 mm. By 27.7 mm, the 
otolith was completely encircled by secondary primor- 
dia, signaling the end of juvenile transformation. 
Discussion 
Sebastes rastrelliger have developed a unique pig- 
ment pattern by 10 mm (Fig. 1C), which allows them 
to be distinguished from other Sebastes spp. At this 
size, the presence of dorsal, ventral, and lateral body 
midline pigment is distinctive for only three species 
(S. dallii [Moser and Butler, 1981], S. rufus [Moser 
and Butler, 1987], and S. saxicola [Laidig et al., 
1996]) that co-occur with S. rastrelliger off Califor- 
nia. All four species have anterior lower jaw, snout, 
and opercular pigments, which could add to the con- 
fusion between these species. One major difference 
in pigmentation between these species is that S. 
dallii and S. rufus have pectoral-fin pigment. We 
found no pectoral-fin pigmentation in S. rastrelliger 
larger than 10.0 mm, and Moreno (1990) found no 
pectoral-fin pigment for individuals smaller than 
8 mm. Sebastes saxicola also lacks pectoral-fin pig- 
ment in fish smaller than 20 mm (Laidig et al., 1996). 
Sebastes saxicola and S. rastrelliger can exhibit simi- 
lar pigmentation at 10 mm. This similarity occurs 
until approximately 18 mm, when S. saxicola devel- 
ops hypural and dorsal fin pigment and when sad- 
dling along the dorsal surface eventually changes into 
a barred pattern. Sebastes rastrelliger was also found 
to have a relatively small pectoral fin for its SL (Table 
2) in comparison with other Sebastes spp. (Moser et 
al., 1977; Richardson and Laroche, 1979; Laroche and 
Richardson, 1980, 1981; Sakuma and Laidig, 1995; 
Laidig et al., 1996) 
Meristics can aid in differentiating S. rastrelliger 
from other species. The average counts of 13 dorsal, 
6 anal, and 19 pectoral-fin rays (Table 1) are similar 
to those observed by Moreland and Reilly (1991) and 
Laroche. 4 Moreland and Reilly (1991) found this com- 
bination of fin-ray counts typical for only two spe- 
cies: S. rastrelliger and S. babcocki. Sebastes babcocki 
has a distinct barred pigmentation pattern and typi- 
cal gill-raker counts of 30-31. Sebastes rastrelliger 
had no barred pattern and average gill-raker counts 
of 22. This count is lower than that observed by 
Moreland and Reilly (1991) (an average of 25) and 
Laroche 4 (an average of 24). Gill-raker counts may 
be low in our study because the gill rakers may not 
have fully developed in some of our specimens 
(Sakuma and Laidig, 1995). Therefore, the use of 
pigment patterns in conjunction with meristics 
should aid in the identification of S. rastrelliger. 
