Se. Reader et Jm. Leis, LARVAL DEVELOPMENT IN THE LUTJANID SUBFAMILY CAESIONINAE (PISCES) - THE GENERA CAESIO, DIPTERYGONOTUS, GYMNOCAESIO, AND PTEROCAESIO, Bulletin of marine science, 59(2), 1996, pp. 310-369
Larvae of eight species representing all four recognized genera in the
lutjanid subfamily Caesioninae were identified by the series method.
We describe in detail development of seven of these covering all gener
a and all the major developmental diversity represented in the materia
l we examined. Larval series were assembled from specimens captured in
the Pacific and Indian Oceans by plankton nets, midwater trawls, and
night light. A few newly settled specimens captured on reefs were also
included. Head spines, fin-spine morphology, meristic values, arrange
ment of the premaxillary processes, and pigment patterns were used to
assemble the series with geographic distributions and adult characters
used to confirm the identifications. Caesionine larvae are characteri
zed by elongate dorsal- and pelvic-fin spines, pelvic-fin rays longer
than spine, and a spine on the postcleithrum typical of all lutjanid l
arvae. They are distinguished from other lutjanid larvae by external o
rnamentation on the fin spines, robust head spines, serrate supraorbit
al ridges and the presence of only one spine on the upper limb of the
outer border of the preopercle until quite late in development. Caesio
spp. may be distinguished from the other caesionine genera by a singl
e lateral premaxillary process in late larvae, whereas Dipterygonotus,
Gymnocaesio and Pterocaesio have two lateral premaxillary processes.
Larvae of four of the eight species of Caesio were identified using fi
n-spine morphology, fin-ray counts, and geographical distribution; the
y are Caesio cuing, Caesio lunaris, Caesio caerulaurea and Caesio tere
s and/or xanthonata. Only C. teres and/or xanthonata is not described
in detail. Dipterygonotus balteatus has the unique fin meristics of D
XIIII-XIV,9-11 and A III,10, and also shares with C. cuning the lowest
pectoral-ray count with a mode of 18. Robust serrae occur on the fin
spines and on the supraorbital ridge. Fin spines are moderate in lengt
h. Gymnocaesio gymnoptera has the most slender, elongate body of any c
aesionine and two serrate leading edges on Dsp2 and Asp2, a characteri
stic shared only with Pterocaesio chrysozona and C. lunaris. Both G. g
ymnoptera and D. balteatus typically have 7-8 procurrent caudal rays c
ompared to 9-10 in all other species of the subfamily. Pterocaesio spp
. can be distinguished from Caesio spp. by the presence of two lateral
premaxillary processes and from D. balteatus by fin-ray counts. G. gy
mnoptera has a noticeably more slender body shape than the Pterocaesio
species described herein. Two of the 10 Pterocaesio species are ident
ified and described: Pterocaesio tile which has a unique fin-ray count
, and P. chrysozona with two leading edges on the Dsp2. In addition, w
e examined a large number of larvae we were able to identify only as C
aesio sp. or Pterocaesio sp., some of which constituted apparent monos
pecific series. None of these has any morphological characters or deve
lopmental patterns not found in the seven species described herein.