Villanueva Gomila et al.: Early life history of Aconthistius potochonicus 
463 
CD 
C 
0 
~o 
03 
0 
0.50 1 
0.40 
0 30 -| 
0.20 
0 
o 
c 
O 
tr 
o 
Q_ 
o 
CL 
B 
0 50 - 
0.40 - 
0.30 
0.20 
e 
1 2 3 
Head length (mm) 
Figure 5 
Body proportions of Acanthistius patachonicus (head re- 
gion) examined for this study and collected on the Argen- 
tine shelf, 2008-2013: (A) snout length and (B) eye diam- 
eter. Bubble size in each plot is proportional to the number 
of larvae in each size range (from 1 to 30 larvae. Solid 
bars on bubbles indicate standard deviations for mean 
head lengths (HLs) and for the proportions of HL. 
“Perciform Species 1” in Brownell (1979) was A. sebas- 
toides (Brownell 4 ; Baldwin and Neira, 1998; Heemstra, 
2010 ). 
Some morphological characteristics of the early 
stages of A. patachonicus were similar to those of 
4 Brownell, C. L. 1979. Personal commun. Oceanic Insti- 
tute, Waimanalo, HI 96795. 
other species in this genus. The eggs, for example, 
resembled those of koester, which has pelagic eggs 
about 0.9 mm in diameter, with a single 0.2-mm oil 
globule (Brownell, 1979). The number of myomeres, 
spines and rays in A. patachonicus were in the same 
range as those from larvae of other Acanthistius 
species (Brownell, 1979; Baldwin and Neira, 1998). 
The preopercular spines in A. patachonicus were as 
conspicuous as those found in western wirrah and 
koester, and the preopercular spine at the posterior 
angle was the largest one among all 3 species. Two 
posttemporal spines were present in western wirrah 
and A. patachonicus. 
However, other characteristics, including pig- 
mentation and the sequence of formation of the fin 
elements, differed among the species. The number 
of pigmentation spots in the head and trunk of A. 
patachonicus was lower than the number observed 
in larvae of both the western wirrah and koester 
(Brownell, 1979; Baldwin and Neira, 1998). Noto- 
chord flexion in A. patachonicus and western wirrah 
began at a similar size but ended at a larger size in 
A. patachonicus (4. 9-7. 5 mm; western wirrah, 4.1- 
5.3 mm: Baldwin and Neira, 1998). In A. patachoni- 
cus , the anal-fin rays began to form after notochord 
flexion, but in western wirrah the dorsal- and anal- 
fin soft rays began to form simultaneously during 
flexion (Baldwin and Neira, 1998), although anal-fin 
development was not complete until the postflexion 
stage (by 7.5 mm). 
Undoubtedly, the most relevant feature that allowed 
reconstruction of the developmental series and linkage 
from the posttransitional stage to the adult stage in A. 
patachonicus was the opercular complex. It was pos- 
sible to track the morphological changes observed in 
the preopercle, opercle, subopercle, interopercle, and 
supracleithrum and to track the development of spina- 
tion in those structures, from the initial development 
Table 2 
Development of meristic characters in Acanthistius patachonicus. Data for adults were obtained from Nakamura et al. (1986) 
and Irigoyen et al. (2008). Asterisks indicate the size ranges at which notochord flexion occurs. w/d=missing data. N=number 
of specimens. 
Body length 
range (mm) 
N 
Dorsal fin 
Pelvic fin 
Pectoral- 
fin rays 
Anal fin 
Branchio- 
stegal 
rays 
Total 
myomeres 
Vertebrae 
Caudal-fin rays 
Spines 
Rays 
Spines 
Rays 
Spines 
Rays 
Upper 
Lower 
2. 0-2. 9 
3 
_ 
_ 
_ 
_ 
_ 
_ 
_ 
_ 
25 
_ 
_ 
_ 
3. 0-3. 9 
4 
- 
- 
- 
- 
- 
- 
- 
- 
25 
- 
- 
- 
4. 0-4. 9 
14 
- 
- 
- 
- 
- 
- 
- 
3-4 
22-25 
- 
- 
- 
5. 0-5.9* 
16 
- 
- 
- 
- 
- 
- 
- 
3-4 
23-26 
- 
- 
- 
6. 0-6. 9* 
5 
II 
- 
- 
3 
2-5 
I 
- 
2-6 
24-25 
5-13 
3-6 
3-9 
7.0-7. 9* 
8 
II-V 
3 
- 
3 
3-7 
l 
- 
4-7 
23-26 
10-16 
3-8 
3-8 
8. 0-8. 9 
1 
VI 
- 
- 
- 
- 
- 
- 
- 
- 
- 
8 
7 
13.0-13.9 
1 
XII 
16 
I 
4 
17 
II 
9 
7 
- 
25 
9 
8 
Adults 
w/d 
XII-XIII 
15-16 
I 
5 
17 
II-III 
8-10 
7 
- 
25 
9 
8 
