135 
NOAA 
National Marine 
Fisheries Service 
Fishery Bulletin 
established 1881 
Spencer F. Baird 
First U S. Commissioner 
of Fisheries and founder 
of Fishery Bulletin 
Early larvae of the swordspine rockfish 
(Sehastes ensifer) identified by 
molecular methods 
Email address for contact author: william.watson@noaa.gov 
Abstract— About 56 rockfish ( Se - 
bastes) species occur in Southern 
California, but the larvae of most 
of them are undescribed. Larval 
rockfishes collected off Southern 
California during the California Co- 
operative Oceanic Fisheries Inves- 
tigations (CalCOFI) cruise in April 
1999 and the Baseline Cowcod Con- 
servation Area (CCA) cruise in Feb- 
ruary 2002 were identified by using 
mitochondrial cytochrome b genomic 
DNA to determine the abundances 
of individual species. About 27% of 
the larvae from the CalCOFI cruise 
and 16% of the larvae from the CCA 
cruise were Sebastes ensifer. Lar- 
val S. ensifer were undescribed for 
most of the size range identified 
here (2. 6-8. 4 mm, early preflexion 
through early postflexion stage). 
Larval S. ensifer are moderately 
deep-bodied and robust and have 
melanophores dorsally and ventrally 
on the gut, in a single ventral row 
on the tail, and on the pectoral fins. 
Starting at about 3.8 mm, melano- 
phores form on the anterior part of 
the mandible. Larvae >6 mm have 
pigment in the mid- and hindbrain 
areas. Preflexion-stage larval S. en- 
sifer are indistinguishable from the 
described larvae of sympatric spe- 
cies in the Sebastes subgenus Se- 
bastomus, except perhaps Sebastes 
rosaceus and S. umbrosus. In later 
stages, S. ensifer may be distin- 
guishable from S. constellatus and S. 
helvomaculatus . 
Manuscript submitted 25 February 2015. 
Manuscript accepted 16 December 2015. 
Fish. Bull. 114:135-143 (2016). 
Online publication date: 21 January 2016. 
Doi: 10.7755/FB.114.2.1 
The views and opinions expressed or 
implied in this article are those of the 
author (or authors) and do not necessarily 
reflect the position of the National 
Marine Fisheries Service, NOAA. 
William Watson (contact author ) 1 
Sharon R. Charter 1 
Cynthia A. Taylor Lawley 1 - 2 
1 Southwest Fisheries Science Center 
National Marine Fisheries Service, NOAA 
8901 La Jolla Shores Drive 
La Jolla, California 92037-1508 
2 Scripps Institution of Oceanography 
University of California, San Diego 
9500 Gilman Drive, Mail Code 0203 
La Jolla, California 92093-0203 
The rockfish genus Sebastes includes 
about 72 species in the eastern North 
Pacific Ocean; approximately 56 of 
these species occur in the Southern 
California Bight (Eschmeyer et al., 
1983; Kendall, 1991), and many are 
important in sport and commercial 
fisheries (e.g., Lenarz, 1987; Leet 
et al., 1992, 2001). The swordspine 
rockfish, Sebastes ensifer Chen, 1971, 
is an abundant, small species (total 
length to about 25-30 cm) that rang- 
es from northcentral California to the 
central Baja California Peninsula, 
Mexico (Love et al., 2002). Although 
not a preferred fishery species owing 
to its small size, S. ensifer contrib- 
utes moderately to recreational fish- 
ery catches because of its abundance, 
and it is sold in Asian fish markets 
(Love et al., 2002). 
Sebastes are live-bearers, and lar- 
vae are readily obtained from preg- 
nant females and occur commonly in 
plankton samples, particularly during 
late winter and spring (Moser et al., 
1993). Owing to this availability and 
to the use of larvae in providing fish- 
ery-independent estimates of spawn- 
ing biomass (e.g., Moser and Butler, 
1987; Moser et al., 2000; Ralston et 
al., 2003; Ralston and MacFarlane, 
2010), considerable effort has been 
directed toward improving our abil- 
ity to identify Sebastes larvae (Ken- 
dall, 1991; Moser, 1996b). However, 
the larvae are difficult to rear (e.g., 
Kendall, 1991), and there is con- 
siderable overlap among species in 
meristic, morphological, and pigment 
characters (Moser, 1996b). Therefore, 
to date, field-collected larvae of only 
7 of the species that occur off South- 
ern California have been visually 
identified with certainty (Moser et 
al., 2000). 
Larvae of S. ensifer, a member of 
the Sebastes subgenus Sebastomus, 
are not readily identifiable. Differ- 
ences among larvae of Sebastomus 
species are quite small (e.g., Moser, 
1996b; Rocha-Olivares, 1998; Rocha- 
Olivares et al., 2000), and currently 
larvae of none of these species can 
be reliably identified with tradi- 
tional morphological and pigment 
characters. Complete larval devel- 
opment for any Sebastomus species 
is still unknown; to date, extrusion 
larvae are known for 7 of the 15 
species, and some later stages are 
known for 4 species, including the 
