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Notice: ©1998 Rosenstiel School of Marine and Atmospheric Science, University of Miami. This manuscript is available at http://www.rsmas.miami.edu/bms and may be cited as: Alshuth, S, R., Tucker, J. W., Jr., & Hateley, J. (1998). Egg and larval development of laboratory-reared sergeant major, Abudefduf saxatilis (Pisces, Pomacentridae). Bulletin of Marine Science, 62(1), 121-133.

BULLETIN OF MARINE SCIENCE, 62(1): 121-133, 1998

EGG AND LARVAL DEVELOPMENT OF LABORATORY-REARED SERGEANT MAJOR, ABUDEFDUF SAXATILIS (PISCES, POMACENTRIDAE)

Sabine R. Alshuth, John W. Tucker, Jr. and Jonathan Hateley

ABSTRACT Development of sergeant major, Abudefduf saxatilis, from late egg to early juvenile is described from captive-spawned and wild eggs and 71 laboratory-reared specimens. General morphological features include lateral compression, deep head, deep abdomen, and increasing preanal length through transformation. Notochord flexion had started in a lO-d old, 5.3 mm TL larva. Flexion was complete by 9.2 mm TL (17 d) and transformation at about 18.7 mm TL (28 d). Pelvic spines and rays developed during early preflexion (4.2 mm TL). The caudal fin began development at 4.4 mm TL. During preflexion (5.0 mm TL), dorsal rays and spines were present, and the anal fin began forming. Anal rays and spines were completed during flexion (9.2 mm TL). Newly hatched larvae had two distinct branched melanophores, one at the anterior part of the forehead, another behind the auditory vesicle. Preflexion larvae (up to 3.5 mm TL) also had melanophores along the ventral body midline between the anus and the notochord tip. Fairly heavy internal pigmentation occurred above the gut. The heavily pigmented pelvic fin was evident in 4.3 mm TL preflexion larvae. During late preflexion (3.5-5.5 mm TL) body proportions and pigmentation changed dramatically. Ventral pigment decreased, and the preanal body became deeper and heavily pigmented with scattered stellate melanophores. Flexion larvae had more pigmentation and were less transparent. The spinous dorsal fin became heavily pigmented during flexion. Throughout postflexion, postanal pig mentation increased, and during transformation, it spread toward the caudal fin. At 32 d, juveniles essentially had full adult coloration. Data from this study and for two species previously described facilitates larval identification for three of the 16 species in the western Atlantic. Pigmentation, pelvic fin size, and pectoral fin rays (17-18) probably are the most useful characters for identification of sergeant major larvae. They have larger, more heavily pigmented pelvic fins and a more heavily pigmented spinous dorsal fin than yellowtail dam selfish (Microspathodon chrysurusv and beaugregory Stegastes leucostictus. Pectoral fins of the latter two species are larger and more pigmented.

One of the most common of all marine tropical fishes is the sergeant major, Abudefduf saxatilis, which belongs to the large perciform family Pomacentridae. The damselfish family contains about 235 species worldwide (Allen, 1975; Nel son, 1984), with most occurring on Indo-Pacific reefs. Sixteen are abundant in parts of the western Atlantic (Robins et aI., 1986). The sergeant major is distrib uted from Rhode Island and the northern Gulf of Mexico to Uruguay and is very common on western Atlantic coral reefs. It also occurs in the eastern Atlantic and Red Sea (Fishelson, 1970). Like many damselfish, sergeant majors deposit demersal adhesive eggs on hard substrates, usually in sheltered areas (Shaw, 1955). The eggs are elliptical and attached by adhesive filaments. Five to seven days after fertilization, hatching of the planktonic larvae takes place right after sunset (Thresher, 1984; Foster, 1987; McAlary and McFarland, 1993), when potential diurnal predators have retired to the reef structure. The known range of hatching times for damselfish is 2-7 d. Although early life history of many damselfish is known, embryological and larval descriptions have been published for relatively few Atlantic species. Thresher (1984) provided a table of typical egg lengths for 11 genera. For the eastern Atlantic, Fishelson (1964) described eggs and hatchlings of Dascyllus aruanus; Re (1980) described eggs and hatchlings of Abudefduf luridus; and Re

121 122 BULLETIN OF MARINE SCIENCE, VOL. 62, NO. I, 1998 and Gomes (1982) described eggs and hatchlings of the Azorian chromis (Chrom is chromis). For the western Atlantic, Brinley (1939) described eggs and hatch lings of beaugregory (Stegastes leucostictus); Myrberg et al. (1967) described eggs of brown chromis (c. multilineata), and Potthoff et al. (1987) described larvae and juveniles of yellowtail damselfish (Microspathodon chrysurus). There are a limited number of papers dealing with A. saxatilis. Shaw (1955) described embryology from fertilization through hatching. Cummings (1968) re ported reproductive habits in the Bahama Islands and briefly described 36-h old larvae. Fishelson (1970) studied behavior and ecology in the Red Sea. Prappas et al. (1990) observed reproductive behavior in a large closed system aquarium. McAlary and McFarland (1993) studied the effect of light and darkness on hatch ing. This report describes development of sergeant major from late egg to early juvenile, 32 d after hatching (dah). Because eggs have been described previously (Shaw, 1955) they will be treated only briefly here for clarification and complete ness.

MATERIALS AND METHODS SPECIMENS, Twenty-five specimens at ages 0,2 and 17 dah were taken from larvae reared in a 3.5 m ' fiberglass tank at HBOI; eggs had been collected from one nest of captive sergeant majors in a 21,200-m' aquarium 8 m deep. Forty-six specimens aged 1.2,4, II, 20, 24, 28, and 32 dah were taken from larvae and juveniles reared in two 1.6-m' fiberglass tanks at the Bermuda Division of Fisheries; eggs had been collected from three nests of wild fish at 10-15 m depths off south central Bermuda. Larvae were sequentially fed oyster trochophores (Bermudian specimens only), rotifers, and copepods, supplemented with Artemia after 10 d. During the 32-d rearing period, water temperature range was 23.9-27.9°C at HBOI (25.0-27.9°C to 17 dah, for described specimens) and 27.0-28.8°C at BDE Specimens were fixed and preserved in 5% buffered freshwater formalin. MEASUREMENTS. Measurements were made with an ocular micrometer in a stereomicroscope, except for standard and total length of postflexion larvae longer than 8 mm SL, which were determined with a millimeter scale. Body length (BL), notochord length (NL), standard length (SL), total length (TL), head length (HL), and head depth (HD), were measured as in Tucker (1982). Snout length, eye diameter (ED), predorsal length (Snout to DSpl), and preanus length (snout to anus) were measured as in Potthoff et al. (1987), Snout to ORal was the horizontal distance along lateral midline from tip of snout to first dorsal ray. Snout to PvSpl was the horizontal distance along lateral midline from tip of snout to first pelvic spine. Body depth was the vertical depth of body measured at transverse level of pectoral-fin origin (maximum depth). MERISTlCS, Most specimens were fairly transparent, and internal structures such as myomeres were visible during preflexion without clearing and staining. Vertebrae were not counted. The following counts were taken from larvae and juveniles with a stereomicroscope: caudal rays, dorsal spines and rays, anal spines and rays, pectoral rays, and pelvic spine and rays. DEVELOPMENTAL TERMINOLOGY. Length is a useful basis for linking characters of unidentified spec imens with those in larval descriptions. However, length might not be the most appropriate basis for comparing larvae of different species, which undergo notochord flexion and transformation at different sizes, usually within a narrow range for a single species but over a wide range for the family or even within a genus, In the present study, both TL and stage of development are given in the text. TL and BL can be compared in Tables I and 2, Yolksac larvae were from hatching until complete exhaustion of yolk and oil. Preflexion, flexion, and postflexion larvae were as defined in Moser ct al. (1977). Juveniles had all fin rays developed and were fully scaled.

RESULTS PIGMENTATION AND MORPHOLOGY (Figs. 1,2) Eggs.-Adhesive, elliptical eggs (Fig. lA) attached in single layer to substrate, Short and long diameters of 20 eggs ranged from 650 to 670 mm and 1100 to 1250 mm. In late stage eggs (1-5 h before hatching), embryos had stellate me lanophores along ventral midline (Fig. lA). Eyes fully pigmented, and mouth ALSHUTH ET AL.: SERGEANT MAJOR DEVELOPMENT 123

Table I. Summarized morphometric data for 63 laboratory-reared Abudefdufsaxatilis. First line: mean ± standard deviation; second line: range. Body length: NL was used through flexion and SL after flexion.

Days after Number of Body length Total length Snout length Eye diameter Head length hatching specimens (mm) (mm) (mm) (mm) (mm)

0.2 20 2.9 ± 0.2 3.1 ± 0.2 0.10 ± 0.08 D.31 ± 0.08 0.55 :!: D.05 2.6-3.2 2.9-3.5 D.08-D.27 D.19-0.36 0.45--0.56 1.2 8 2.9 ± 0.2 3.2 ± 0.2 D.18 ± 0.D7 0.30 ± 0.07 0.56 ± 0.06 2.7-3.2 2.9-3.4 0.11-0.28 0.I8-D.35 0.46-0.63 4.0 5 3.3 ± 0.1 3.6 ± 0.2 0.31 ± D.16 0.47 ± D.15 o.rz ± 0.08 3.2-3.4 3.4-3.9 0.20-D.59 0.40-0.73 0.59--0.79 II 5 4.8 ± 0.3 5.7 ± 0.5 D.62 ± D.IO 0.75 ± 0.D8 1.8 ± 0.\ 4.5-5.2 5.0-6.5 0.53-0.73 0.66-0.86 1.6-1.9 17 5 6.8 ± 0.5 9.2 ± 0.5 0.91 ± 0.19 0.96 ± 0.17 2.7 :+: 0.3 6.1-7.0 9.1-10.0 0.59-1.1 0.73-1.2 2.2-3.0 20 5 9.2 ± 0.8 10.8 ± 1.5 D.88 ± 0.\1 1.3 ± 0.2 3.6 ± D.7 8.0-10.0 9.1-13.0 D.79-1.1 1.1-1.5 2.6-4.6 24 5 8.6 ± 0.6 11.2 ± 1.3 1.0 ± D.2 1.4 ± 0.1 3.6 ± 0.2 8.0-9.0 10.0-13.0 0.8-1.3 1.3-1.5 3.2-3.8 28 5 15.2 ± 1.3 20.2 :+: 1.6 1.8 ± 0.4 2.0 ± 0.2 5.5 ± 0.6 13.0-16.0 17.1-22.0 1.4-2.2 1.7-2.2 4.8-6.1 32 5 17.2 ± 1.5 23.2 ± 1.5 1.8 +- D.I 2.2 :!: 0.1 6.5 ± 0.2 15.1-19.0 21.0-25.0 1.7-1.9 2.2-2.3 6.2-6.7 Days after Number of Body length Total length Snout length Eye diameter Head length hatching specimens (mm) (mm) (mm) (mm) (mm)

0.2 no dorsal no dorsal no pelvic 1.0 I t· O.10 D.63 ± 0.06 0.64 :!: 0.02 spines visible ray visible spines visible 0.82-1.1 D.59-0.70 0.61-0.69 1.2 no dorsal no dorsal no pelvic D.99 ± 0.09 0.65 ± 0.05 0.67 ± 0.02 spines visible ray visible spines visible 0.84--1.02 0.60-0.70 0.63-0.70 4.0 no dorsal no dorsal no pelvic 1.4 ± 0.3 0.9 :!: 0.3 1.1 ± 0.4 spines visible ray visible spines visible 1.3-1.9 0.7-1.5 0.9-1.7 II 2.2 ± 0.1 3.2 ± 0.2 2.0 ± 0.1 2.7 +- D.I 2.0 :!: 0.2 2.2 ± 0.2 2.1-2.3 2.9-3.4 1.9-2.1 2.5-2.8 1.8-2.2 2.0-2.4 17 3.2 +- 0.2 4.7 ± 0.8 3.1 ± 0.9 4.2 :!: D.3 3.0 -r- 0.5 3.1 ± 0.6 3.1-3.5 3.4-5.4 2.2-4.6 3.8-4.4 2.1-3.4 2.2-3.6 20 4.0 :+: 0.6 6.3 ± 1.4 3.7 +- 0.4 6.D ± D.8 4.3 +- 0.4 4.6 +- 0.4 3.5-4.8 4.3-7.9 3.3-4.2 5.3-7.3 3.8-4.7 4.0-4.9 24 3.9 _ 0.2 6.4 ± 0.7 3.8 ± 0.2 5.9 :!: 0.2 4.4 :!: 0.4 4.7 ± 0.5 3.6-4.2 5.6-7.2 3.6-4.2 5.7-6.2 3.8-4.8 4.0-5.1 28 6.5 ± 0.9 12.2 ± 1.7 6.8 ± 0.9 10.6 ± 1.5 8.2 +- 1.1 8.6 ± 1.0 5.3-7.4 10.1-13.5 5.6-7.4 8.6-11.9 6.4-8.9 6.8-9.2 32 7.9 ± 0.4 13.8 ± 0.7 7.6 +- 0.3 12.4 .+: 0.6 9.1 :!: 0.5 9.5 ± 0.6 7.4-8.3 13.1--14.7 73--7.9 11.4-12.7 8.2--9.5 8.6-10.0 with moveable jaws. Otoliths present in auditory vesicle. Yolk homogeneous with numerous, scattered, branched melanophores on yolksac. Perivitelline space small. Single large oil globule clear and unpigmented. Hatchlings (2.9-3.5 mm TL, n = 20).-Pigmentation of newly hatched larvae (Figs. IB, 2A) light. Larvae hatched at mean TL of 3.1 mm, with well-developed mouth and pigmented eyes. Yolk mostly exhausted. At 0.5 h after hatching, oil globule diameter of 10 larvae ranged from 210 to 280 urn (mean 250 urn). Anus near yolksac. Two distinct branched melanophores on the head: one anterior to eye at anterior part of forehead and another posterior to auditory vesicle. Branched melanophores along ventral body midline between the anus and notochord tip. Internally, area above the gut heavily pigmented. This pigmentation diffuse or in form of stellate or punctate melanophores. tv -!'o

Table 2. Body proportions of 63 laboratory-reared Ahudefduf saxatilis. Except for body length, values are in percentage of BL and are given as: First line: mean ± standard deviation; second line: range. Values are derived from Table I. NL was used through flexion and SL after flexion.

Measurement Hatching Yolk exhaustion Preflexion Flexion Postflexion Early juvenile c Body length (mm) 2.9 ± 0.2 3.3 ± 0.2 4.8 ± 0.3 6.8 ± 0.5 10.9 ± 1.3 18.2 ± 1.5 '"t"" t"" 2.6-3.2 3.2-3.4 4.5~5.2 6.1-7.0 9.9-13.1 17.1-19.0 ...,m Snout lengthIBL 6.1 ± 2.4 9.5 ± 3.6 12.9 ± 1.4 13.3 ± 2.1 10.1 ± 1.6 11.4 ± 1.4 Z 3.7-9.5 6.0-11.5 11.3-14.7 9.9-15.1 7.9-12.4 10.1-13.6 0 ." Head lengthIBL 19.4 ± 2.6 21.8 ± 2.5 37.6 ± 1.7 39.5 ± 2.2 40.8 ± 5.8 36.7 ± 1.4 s: 15.4-22.7 17.9-23.4 35.2-39.1 36.3-42.2 29.3-46.3 34.4-38.2 » Eye diameterlBL 10.4 ± 2.1 13.5 ± 3.8 15.8 ± 0.73 14.1 ± 1.8 14.7 ± 1.3 13.0 ± 0.7 '"Z 12.1~17.0 m 6.9-12.6 11.7-17.1 14.7-16.7 12.5-16.1 11.8-14.0 CJ' Snout to DSpllBL no dorsal no dorsal 45.7 ± 1.2 46.3 ± 2.5 44.3 ± 5.1 44.2 ± 2.6 m'i z spines visible spines visible 43.7-46.4 44.6-50.0 36.4-53.4 39.9-47.4 n Snout to DRallBL no dorsal no dorsal 66.5 ± 1.5 68.5 ± 7.4 69.8 ± 11.1 80.0 ± 3.2 !" < ray visible ray visible 64.6-68.1 57.1-77.3 53.6-88.1 75.2-84.5 0 Snout to PvSpllBL no pelvic no pelvic 42.2 ± 2.3 45.3 ± 11.7 42.3 ± 3.4 44.6 ± 2.1 t"" o- spine visible spine visible 40.1-45.1 37.7-65.7 37.7-46.2 43.0-47.6 r- z Snout to anuslBL 34.1 ± 1.9 42.1 ± 6.5 56.0 ± 3.9 61.6 ± 2.4 66.8 ± 7.9 71.4 ± 3.1 0 31.6-36.8 36.4-49.9 53.3-62.4 57.6-63.8 55.9-80.9 66.0-74.8 r: Head depthIBL 22.4 ± 1.5 28.2 ± 9.8 42.3 ± 3.0 43.3 ± 5.6 49.6 ± 3.5 53.9 ± 2.8 ::c-o 20.0--24.2 23.0~37.4 38.6-45.1 34.3-49.0 42.9-53.4 49.0-58.5 cc Body depthIBL 23.1 ± 1.8 33.7 ± 10.5 46.2 ± 2.0 45.6 ± 5.8 51.2 ± 3.8 56.3 ± 2.8 21.1-25.2 27.1-48.6 44.0-47.9 38.3-50.9 45.5-54.9 52.2-61.3 Total lengthlBL 108.1 ± 3.1 108.4 ± 5.3 124.0 ± 1.8 132.9 ± 9.6 120.7 ± 8.7 134.7 ± 2.7 105.0-113.2 101.8-113.4 121.0-125.6 128.6-150.0 111.l~133.0 131.3-138.5 ,\LSHlJfH ET ,\L,: SERGEA T MAJOR DEVeLOPMENT 125

Figure I, Almdefduf saxnrilis development (Photos by S, AI hlllh): il) late stage eggs (live); (h) halehling (30 min. 3.3 mm TL. live); (e) prenexion larva (9 dah. 4.3 mm TL. live); (d) juvenile (28 dah. 16A 111111 TL, preserved).

Yo/hac (2.9-3.6 mm TL, n = 8).-Sergeant major embryos use much of their yolk during incubation, which typically lasts 5-7 d. No major pigmentation changes occurred in yolksac larvae. One day after hatching, additional intemal yellow pi.gmentation (xanthophores) visible behind auditory vesicle above gut. and pectora] fins present.

Yolk ex.haustion (3.4-3.6 mm TL, n = 5).-Yolk and oil used up by 3-4 dah (3.5 mm mean TL). Larvae had one large branched melanophore n front of head, distinct melanophores along ventral midline, and internal melanophores above gut.

Preflexion. (3.5-5.5 mm TL, n = 7).-Body propm1ions and pigmentation changed dramatically (Fig. IC,2B). Throughout this stage pigmentation of ventral midline decreased. At 9 dah (4.3 mm mean TL), the preanal body became very deep and fairly heavily pigmented. Internal pigmentation characteristically in form f bold stellate melanophores above gut. Large stellate meJanophores also ccuned on operculum behind eye and behind auditory vesicle. Pigmentation of postanal body characterized by di tinct scattered, stellate melanopbores along ventral and lateral midlines. Pelvic fin had distinct dark pigmentation and first caudal rays visible. At 11 dah (5.7 mm mean TL), degree of development varied widely, but length range short. Half of specimens in preflexion (rest described in next paragraph). Pigmentation of deep preanal body characterized by extensive scattered stellate melanophores. Pigmentation on stomach, operculum, and pelvic fins not changed noticeably. More caudal rays developed. Although marginal finfold still present. dorsal fin well d veloped. 126 BULLETIN OF MARINE SCIENCE, VOL. 62, NO. I, 1998

Flexion (5.6-9.2 mm TL, n = 13).-Larvae (Fig. 2C,D) usually had increased pigmentation and less transparency, especially in postanal body. At 11 dab, half of specimens undergoing notochord flexion and with major changes in body pro portions. At 17 dah (9.2 mm mean TL), half of larvae described as follows: Body more rounded and deeper, especially in stomach area. Preanal pigmentation more ex tensive. Rays present in dorsal, pelvic, and caudal fins. Anal fin developing. At 17 dah, other half had deeper, rounded, less transparent, bodies with in creased pigmentation, especially postanally. At 20 dab, live larvae had first obvious development of vertical black stripes. On day 21, they began schooling.

Postfiexion (9.9-13.1 mm TL, n = 6).-At 24 dah (11.2 mm mean TL), half of specimens described as follows: Had deep, rounded, less transparent body, pig mentation greater, especially postanally. Fin rays increased. Melanophores present on dorsal and pelvic fins. Other half had more rounded bodies with more extensive pigmentation and designated as late larvae just prior to transformation. Distinct vertical band of scattered stellate melanophores present just below posterior dorsal fin. Yellow chromatophores present on pelvic fins. About half of this group had forked caudal fins, and the others had rounded fins.

Juveniles (16.4-25.0 mID TL, n = 10, no specimens in range 13.2-16.3 mm). Youngest juvenile 28 d old (16.4 mm). At 32 dah (23.2 mm mean TL), nearly all fish had transformed (Fig. 1D). At both HBOI and BDF, live 32-d-old fish had complete vertical bars and dorsal yellow pigmentation typical of adults. In pre served specimens, pigmentation seen to spread closer to caudal fin, and yellow chromatophores visible on anterior dorsal fin. Spinous dorsal and pelvic fins heavily pigmented. At 32 dah, pellets first offered to juveniles and readily eaten.

MORPHOMETRIes (Tables 1,2) General morphological features of larvae and juveniles include lateral com pression, deep head, and deep abdomen. Snout relatively short in larvae and juveniles. Larval snout lengthIBL increased slightly during yolk depletion, in creased during preflexion to flexion, then decreased at postflexion. Head moderate in early larvae but relatively large in late larvae and juveniles. Larval HL/BL increased slightly until yolk exhaustion and then increased sharply at preflexion. Eye of both larvae and juveniles large. Larval eye diameter/BL increased from hatching to preflexion, and decreased at transformation. Predorsal length did not vary much. Snout to first dorsal ray/BL increased slightly from preflexion to postflexion, then increased sharply at transformation. Snout to first pelvic spine lengthIBL was relatively constant. Snout to anus length/BL, head depthIBL, and body depthIBL steadily increased. Although caudal fin was growing, flexion pro cess prevented totallengthIBL from increasing constantly. Fin Development and Meristics (Table 3).-Preflexion larvae up to 4.0 mm TL had 24-26 myomeres. During preflexion (4.3 mm TL), caudal fin development began with deep constriction of marginal finfold and thickening below the uro style, and about 12 rays were formed. At 5.0 mm TL, 18-21 rays present. Fin became more rounded and larger, with distinct caudal peduncle, but finfold was still evident. During flexion and postflexion, number of principal rays increased ALSli Tl-I ET AL.: S RGEANT MAJOR D _VE OPMENT 127

......

. \ .

1 mm

lmm

Figure 2. Abudejcil!F saxtllilis larval 'wges: (a) hatchling (30 min. 3.3 mm TL); (b) preftexion (5 dah, 3.6 mm TL); (c) mid-flexion (15 dah, 6.6 mm TL): (d) latc flexion (24 dah. 9.3 mm TL). 128 BULLETIN OF MARINE SCIENCE, VOL. 62, NO. I, IYYX

Table 3. Meristic ranges for 63 laboratory-reared Ahudejduf saxatilis

Days after Caudal Dorsal Dorsal Anal Anal Pectoral Pelvic Pelvic hatching rays spines rays spines rays rays spines rays Myomeres 0.2 0 0 0 0 0 0 0 0 24-26 1.2 0 0 0 0 0 0 0 0 24-26 4.0 0 0 0 0 0 0 0 0 24-26 11 18-21 7-9 10-13 0-1 10-12 6-8 1* 5* 17 24-26* 10 12-14* 2* 12-13* 9-12 I 5 20 24-26 11-12 13-14 2 13 12-14 I 5 24 26 10-12 12-14 2 12-13 15-17* 1 5 28 25-26 12-13* 13-14 2 13 17-18 I 5 32 26 13 12-14 2 13 17-18 I 5 * First reached adult number. to 24-26. When fully developed, caudal fin has 26 principal rays, of which 22 are branched. Finfold still visible during preflexion, as dorsal fin developed. First dorsal fin rays and spines occurred in preflexion larvae of 5.0 mm TL; dorsal fin had 7-9 spines and 10-13 rays. By 6.4 mm TL, finfold was lost. Although number of dorsal rays characteristic of juveniles was reached during preflexion, number of spines increased slowly during flexion and postflexion. Dorsal fin reached its final shape by 9.3 mm TL (Fig. 2D). Full complement of 13 spines and 13 rays present in 16.4 mrn TL and longer juveniles. Development of anal fin evident at 5.0 mm TL by thickening at the base, but individual ray bases could not be distinguished. Finfold still present and contig uous with dorsal finfold. Preflexion larvae of 5.5 mm TL had up to one anal spine and 10-12 rays; finfold narrower. The two anal spines and 13 rays characteristic of juveniles formed during flexion. Last three anal rays are branched in juveniles. Pectoral fin evident at 3.5 mrn TL as fleshy, rayless structure. No rays discern ible at yolk exhaustion. At 5.0 mm TL, first rays present. Number increased slightly during 6-8 dah (preflexion), with total of 9-14 formed during flexion and 15-17 during postflexion. Final fin shape developed during late flexion. Full com plement of 17 rays present in 12.3 mm TL postflexion specimen. Heavily pigmented pelvic fin well developed in 4.3 mm TL preflexion larvae (Fig. 1C). Juvenile complement of one pelvic spine and five rays formed early during preflexion.

DISTINGUISHING CHARACTERS (Tables 4,5) Victor (1987) reported that fin ray counts, otolith morphology, and otolith in crements were good characters for identifying Pacific pomacentrids. In pomacen trids, the gut becomes coiled and compact early in development (Leis and Rennis, 1983; Leis and Trnski, 1989). We did not examine otoliths for this paper, but fin ray counts are useful for late larvae and juveniles of Atlantic species, too. Miller and Jorgenson (1973) listed representative meristics for seven pomacentrid species (1-4 specimens each) in the genera Abudefduf, Chromis, and Stegastes. Counts of vertebrae, dorsal spines, anal spines, and caudal rays were similar. Abudefduf spp. and Chromis spp. had fewer dorsal rays (12-13 vs 15-16) and anal rays (10-12 vs 13-14) than Stegastes spp. Table 4 gives fin ray counts for sergeant majors from three locations. Because sergeant major larvae typically stay near the bottom and are not likely to drift in ~ r C/O :t Table 4. Comparison of reared Abudefduf saxatilis fin ray counts with those of wild juveniles from six locations. Less common counts are in parentheses. ...,C :r Percentages of specimens having counts in the ranges not enclosed in parentheses are given in the table. All specimens had 13 dorsal spines, 2 anal spines, I rr pelvic spine, and 5 pelvic rays. ~ r- v tr Caudal % in Pectoral % in Dorsal % in Anal % in ~ range rays c Source n rays range rays range rays range tr ~ Bermuda (reared) 10 (5)6 + 8 + 7 + 5 80 17(18) 70 (12)13(14) 80 13 100 2 Bermuda (wild) 39 (6)5 + 8 + 7 + 5(6) 70 (17) 18 79 (12)13(14) 69 (12)13 51 i Nassau, Bahamas 30 (6)5 + 8 + 7 + 5(6) 80 (17)18 85 13 100 12(13) 92 c Long Key, Florida 31 4 - 5 + 8 + 7 + 5(4,6) 90 (17) 18 77 13(14) 64 (12)13 71 ~ Grand Cayman 45 (5,7)6 + 8 + 7 + 6(5) 49 (17)18 89 (12)13(14) 91 (12)13 96 v St. Thomas 20 (6)5 + 8 + 7 + 5(6) 76 (17)18 80 (12)13 85 12(13) 80 '"< r- Barbados 4 (5)6 + 8 + 7 + 6(5) 50 18 100 13 100 (12)13 75 o'" ." l:: ...,~

tv '0 w o

Table 5. Comparison of selected larval and juvenile characters of sergeant major (Abudefduf saxatilisi and yellowtail damselfish (Microspathodon chrysurus, ttl C Potthoff et al., 1987): size and age from first development to completion. Less common counts are in parentheses. r r ~ Z Abudefduf saxatilis Microspathodon chrysurus o ." Adult number BL (mm) Age (dah) Adult number BL(mm) Age (dab) s: :> ;

20 -E -E I I- 15 CJ Z W .....J .....J 10 or::( I- 0 I- 5

OL.....<....<...... o....I..l...... I...L...... J...... ,... o 10 20 30 DAYS AFTER HATCHING Figure 3. Abudefdufsaxatilis growth from hatchling to juvenile. Dots represent fish raised in Florida at 23.9-27.9°C and triangles represent those raised in Bermuda at 27.0-28.8°C. the plankton (Tucker, pers. obs.), localized recruitment is more significant than with planktonic species. The slight differences in fin ray counts in Table 4 are not conclusive evidence of population differences, but suggest an area for further investigation. Counts are presented here for identification purposes. Sergeant majors hatched at a total length of 2.6-3.2 mm with functional eyes and digestive systems. They began feeding within 0-2 h after hatching (hah) and grew quickly (Fig. 3). Transformation into juveniles occurred mainly during 28 32 dah (range 12.6-19.0 mm SL). Yellowtail damselfish transformed at about the same size (~17 mm SL), but a greater age (between 50 and 79 dah, Potthoff et aI., 1987). Table 5 compares developmental characteristics of sergeant major and yellow tail damselfish. Early characteristics of four western North Atlantic pomacentrids are summarized below. Sergeant major, A. saxatilis: large, heavily pigmented pelvic and spinous dorsal fins; small, sparsely pigmented pectoral fin. Egg diameters 650-670 urn and 1100-1250 u.m, single oil globule, narrow perivitelline space, deposited on nearly any hard substrate that can be cleaned, with upward, downward, or sideways orientation. Hatchlings 2.9-3.5 mm TL. Flexion complete at 10-13 mm TL and transformation at 16-25 mm TL (about 28-32 dah). Settled at 17-20 dah on an artificial reef at St. Croix (Wellington and Victor, 1989). Yellowtail damselfish, Microspathodon chrysurus (Potthoff et aI., 1987): pelvic fin small and sparsely pigmented; spinous dorsal fin not heavily pigmented; large, heavily pigmented pectoral fin. Settled at about 21-27 dah at St. Croix (Welling ton and Victor, 1989). Beaugregory, Stegastes leucostictus (Brinley, 1939): eggs about 400 X 800 u.m and deposited in empty conch shells or on the under surface of rocks, dead sea 132 BULLETIN OF MARINE SCIENCE. VOL 62. NO. I. 199X fans, shells, cans, bottles, and other hard substrates; hatchlings about 3 mm long, with a few melanophores on the dorsal head surface, dorsal body cavity heavily pigmented, and a single lateral row of melanophores from the yolk sac to the tail base; pectoral fins of early larvae with brownish chromatophores and large. Brown chromis, Chromis multilineata (Myrberg et aI., 1967): eggs were about 500 X 600 urn and were deposited in large masses on Sargassum.

ACKNOWLEDGMENTS We thank Walt Disney Imagineering, the Overseas Development Administration, and the Bermuda Division of Fisheries for partial financial support, and the Living Seas of Disney World for providing eggs from the aquarium; also P. Bush (Cayman Islands Natural Resources Laboratory), I. H. von Herbing and M. Tupper (Bellairs Research Institute, Barbados), Wm. Mitchell and J. Gray (Bermuda Natural History Museum), E. Phillips (Bahamas Department of Fisheries, collection by Coral World Marine Park), P. Sikkel (University of the Virgin Islands, St. Thomas), and Wm. Gibbs (Keys Marine Laboratory, Long Key, Florida) for providing the wild specimens. Technical support was provided by staffs of the HBOI Aquaculture Division and Bermuda Division of Fisheries. This is contribution 1136 from Harbor Branch Oceanographic Institution.

LITERATURE CITED Allen, G. R. 1975. Damselfishes of the South Seas. TF.H. Publications, Neptune City, New Jersey. 240 p. Brinley, F. J. 1939. Spawning habits and development of beaugregory iPomacentrus leucostictusv. Copeia 1939: 185-188. Cummings, W. C. 1968. Reproductive habits of the sergeant major, Abudefduf saxatilis, (Pisces, Po macentridae) with comparative notes on four other damselfishes in the Bahama Islands. Ph.D. Diss., Univ. Miami, Coral Gables, Florida. 173 p. Fishelson, L. 1964. Observations on the biology and behaviour of Red Sea coral fishes. Bull. Sea Fish. Res. Sta., Haifa 37: 11-26. ---. 1970. Behavior and ecology of a population of Abudefdufsaxatilis (Pornaccntridac, Teleostei) at Eilat (Red Sea). Anim. Behav. 18: 225-237. Foster, S. S. 1987. Diel and lunar patterns of reproduction in the Caribbean and Pacific sergeant major damselfishes Abudefduf saxatilis and A. troschelii. Mar. BioI. 95: 333-343. Leis, J. M. and D. S. Rennis. 1983. The larvae of Indo-Pacific coral reef fishes. New South Wales Univ. Press, Kensington. 269 p. ---and T Trnski. 1989. The larvae of Indo-Pacific shorcfishes. New South Wales Univ. Press, Kensington. 371 p. McAlary, F. A. and W. N. McFarland. 1993. The effect of light and darkness on hatching in the pomacentrid Abudefduf saxatilis. Env. BioI. Fish. 37: 237-244. Miller, G. L., and S. C. Jorgenson. 1973. Meristic characters of some marine fishes of the western Atlantic Ocean. Fish. Bull., U.S. 71: 301-312. Moser, H. G., E. H. Ahlstrom and E. M. Sandknop. 1977. Guide to the identification of scorpionfish larvae (family Scorpaenidae) in the eastern Pacific with comparativc notes on species of Scbastes and Helicolenus from other oceans. U.S. Dept. Comm., NOAA Tech. Rep., NMFS Circular no. 402.71 p. Myrberg, A. A., Jr., D. Brahy and A. R. Emery. 1967. Field observations on the reproduction of the damselfish, Chromis multilineata (Pomacentridae) with additional notes on general behavior. Co peia 4: 819-827. Nelson, J. S. 1984. Fishes of the World. John Wiley and Sons, New York. 523 p. Potthoff, T, S. Kelley, V. Saksena, M. Moe and F. Young. 1987. Description of larval and juvenile yellowtail damselfish, Microspathodon chrvsurus, Pomacentridac, and their osteological devel opment. Bull. Mar. Sci. 40: 330-375. Prappas, J. M., L. E. Greene and R. White. 1990. Reproductive behavior of the sergeant major, Abudefduf saxatilis, within a closed system aquarium. Env. BioI. Fish. 31: 33-40. Re, P. 1980. The eggs and newly hatched larvae of Abudefduf luridus (Cuvier, 1830), (Pisces: Po macentridae) from the Azores. Arquivos Mus. Bocage 7: 109-116. ---and J. Gomes. 1982. The eggs, newly hatched larvae and juveniles of the Azorian Chromis (Pisces: Pomacentridae). Bolm. Soc. Port. Cienc. Nat. 21: 9-18. Robins, C. R., G. C. Ray and J. Douglass. 1986. A field guide to Atlantic coast fishes of North America. Peterson Field Guide series, no. 32. 354 p. Shaw, E. S. 1955. The embryology of the sergeant major, Ahudefduf saxatilis. Copeia 2: 85-89. ALSHUTH ET AL.: SERGEANT MAJOR DEVELOPMENT 133

Thresher, R.E. 1984. Reproduction in reef fishes. TF.H Publications, Neptune City, New Jersey. 399 p. Tucker, J. W., Jr. 1982. Larval development of Citharichthvs cornutus, C. gymnorhinus, C. spilopterus, and Etropus crossotus (Bothidae), with notes on larval occurrence. Fish. Bull., U.S. 80: 35-73. Victor, B. C. 1987. Growth, dispersal, and identification of planktonic labrid and pomacentrid reef fish larvae in the eastern Pacific Ocean. Mar. BioI. 95: 145-152. Wellington, G. M. and B. C. Victor. 1989. Planktonic larval duration of one hundred species of Pacific and Atlantic damselfishes (Pomacentridae). Mar. BioI. 101: 557-567.

DATE ACCEPTED: October 7, 1996.

ADDRESSES: (S.R.A. and J.W.T.) Harbor Branch Oceanographic Institution, 5600 North U.S. Highway I, Fort Pierce, Florida 34946; (J.H.) Division or Fisheries, Department ofAgriculture, Fisheries & Parks, P.O. Box CR 52, Crawl CR BX, Bermuda. PRESENT ADDRESS: (S.R.A.) Indian River Community College. 3209 Virginia Avenue, Fort Pierce, Florida 34981.