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BULLETIN OF MARINE SCIENCE, 41(2): 432-440,1987

INSHORE : A DISTINCTIVE ASSEMBLAGE?

C. Lavett Smith, James C. Tyler and Loretta Stillman

ABSTRACT Our collections oflarval made at underwater lights on the outer shelves of reefs in the Caribbean yield large numbers of specimens mostly representing only a few of the families of fishes that inhabit coral reefs as adults. Although it is difficult to sample close to the reefs and methods of taking quantitative samples there have yet to be devised, preliminary comparisons of our near-reef data with those from ichthyoplankton collections made by others during extensive offshore surveys suggest that the inshore larval fishes constitute a distinctive assemblage. Not only are different taxa dominant, but few inshore larval fishes show the morphological specializations that characterize many of the offshore larvae. We postulate that tropical marine larvae tend to be specialized either for long distance transport or for avoiding being swept downstream by offshore currents. This seems to indicate that there are two groups of larval fishes: a far-field assemblage of larvae that are morpho- logically modified or behaviorally specialized for long distance transport by ocean currents and a near-field assemblage of un specialized larvae that avoid currents and spend their entire lives in the vicinity of the reefs.

It is widely accepted that nearly all fish species that live on coral reefs have mobile life history stages, spending either the or larval stages or both as members of the . During this pelagic phase the fish undergo tremendous morphological changes and face environmental challenges that are drastically different from those they will face on the reef during their benthic existence. Since successful completion of the planktonic phase is a prerequisite to their settlement and subsequent life history, it is hardly surprising that a great deal of research effort is being devoted to studies of ichthyoplankton and to the processes by which fish larvae settle from the open water community and become part of the benthic ichthyofauna (McFarland and Ogden, 1985). Still, this research is in its infancy and we know very little of the events that take place during the early life history stages. Although large scale offshore surveys have given a general picture of the distribution of fish larvae in the Caribbean (Richards, 1984), there is still little information on the distribution of larvae in the immediate vicinity of coral reefs. Traditionally, the planktonic larval stages of marine fishes have been regarded as rather helpless organisms that drift passively at the mercy of oceanic currents. It has been suggested (Johannes, 1978) that many fishes select spawning sites where eddies or gyres tend to keep the in the vicinity of the reefs where they are spawned. Lobel and Robinson (1986) reviewed the current patterns in the vicinity of the Hawaiian Islands and concluded that mesoscale current and eddy systems can entrap larval fishes and retain them offshore for long enough periods for them to complete the planktonic phase of their life history and that these eddy currents can account for some passive return to the vicinity where the eggs originated. Leis (1986) provided evidence that more larvae are retained on the windward side of Lizard Island, , than on the leeward side. However, Leis (I983) reported that larvae belonging to the genus Thalassoma have been taken at sea more than 1,000 km from the nearest reefs which are the of the adults. Apparently, there is sufficient variation so that substantial numbers of eggs and larvae "escape" from their home area and are carried long distances. Thus, the deployment of planktonic life stages in eddies and gyres serves 432 SMITH ET AL.: INSHORE ICHTHYOPLANKTON 433 two opposing demands. It enhances the probability that a large number of eggs and larvae will remain close to the habitat necessary to complete their life cycle but at the same time allows enough larvae to escape to assure that some will be carried to distant patches of habitat for colonization and the maintenance of genetic diversity. In this paper we compare the larvae that occur close to the reef (within 10 m of the substratum) with those found in open water. Although this comparison is necessarily preliminary and in many ways crude, two observations stand out. First, the open ocean collections contain different taxonomic groups of fishes than the inshore collections; and second, many larval fishes that live in the open sea have striking anatomical specializations whereas larvae collected close to coral reefs rarely show such modifications.

METHODS AND MATERIALS Over the years sophisticated methods of collecting plankton in the open sea have been developed and used extensively. With large vessels and opening and closing nets it is possible to make reasonably accurate estimates of abundances of larvae at different depths and in various geographic regions. Richards (1984) has recently summarized the distribution and of ichthyoplankton in the Caribbean Sea. Unfortunately, the quantitative methodology of the blue-water planktonologist cannot be directly applied to fine-scale near-shore studies. Large vessels cannot work close to reefs and the geometric complexity of the reefs makes it impossible to maneuver even small nets close to the reef from the surface. Even surface tows from small boats are subject to biases because of the difficulty of maintaining accurate speed and positions in surf, wind and currents. Consequently, in order to study the near-reef plankton we have had to resort to small nets towed by divers and to sampling the larval fishes that are attracted to lights placed on the sea floor. The latter has proved to be effective for some species, especially when the lights are employed on the outer slope of the reef; i.e., seaward of the reef crest. One of our light collections on the outer slope at Carrie Bow , Belize, contained approximately 24 times as many larvae as the average of 5 collections from behind the reef crest. Our recent Carrie Bow Cay research is beginning to provide western Caribbean plankton data for comparison to our more extensive eastern Caribbean data base described below. Study Area. - The Salt River Canyon is a notch in the of the north coast of S1. Croix, U.S. Virgin Islands. Its long axis runs approximately north and south. Its west wall is an almost vertical, thriving reef; its east wall slopes more gently and has a dense growth of gorgon ian . The floor of the canyon is sand, with patches of Halophila. 13 m deep at the inner end, sloping gradually to a depth of 26 m, then more steeply to about 80 m where it joins the precipitous outer wall of the fringing reef. Currents in the canyon are mostly tidal; only during periods of exceptional rainfall is there a substantial continuous seaward flow driven by freshwater runoff. Bottom tow collections were made in various parts of the canyon at depths between 16 and 40 m by divers towing a small that could be maneuvered close to the bottom and around coral colonies. The 0.505-mm mesh net was 128 em long with a 30-cm diameter mouth opening. It was mounted on an aluminum frame with two handles and fitted with a collecting bucket with side ports covered with the same mesh. The same net was used at night to sweep the beam of a flood light mounted on the NOAA habitat HYDROLAB which was located at the inner end of the canyon in water 16 m deep. Surface collections in the canyon were made with a 50-em plankton net towed from a sma1\ outboard motorboat at and just below the surface. Samples from two offshore stations were made with multiple opening and closing nets (MOCNESS). These latter collections were made by the National Marine Service Southeast Fisheries Center, Beaufort Laboratory, as part of the OTEC project, one at Lat. 17°52.5'N, Long. 64°29.5'W; the other at Lat. 17°50.0'N, Long. 64°48.0'W. Seven nets with 1 x IA-m openings were deployed between the surface and 100 m for 10- and 20-m (vertical distance) oblique tows. Our bottom tows and light sweeps were made 26 April through 2 May 1984 and 16-21 May 1985, and our surface tows 23-28 September 1985. The MOCNESS samples of the NMFS were co1\ected 9 May 1984.

RESULTS Taxonomic Comparisons. -Our preliminary survey of the literature on the fish fauna of the Caribbean area indicates that the total fish fauna is about 1400 species 434 BULLETIN OF MARINE SCIENCE, VOL. 41, NO.2, 1987 representing approximately 185 families (Smith, ms.). Obviously, such an estimate cannot be precise because undoubtedly there are some species that occur in the region which simply have not yet been reported. Nevertheless, we believe that this estimate is within 10% of the actual number. For the following discussion we have eliminated 23 families of elasmobranch fishes since they do not have planktonic larvae. We estimate that 85 families (52.5%) of bony fishes contain species that live on reefs or in other inshore en vironmen ts and 77 families (47.5%) are strictly offshore fishes. Thus, slightly more than half the families known from the Carib- bean region are inshore fishes. In his report on the larval fishes of the Caribbean, Richards (1984) reported 86 families (53.1 % of the total) of which 50 (58.1 %) are inshore families and 36 (41.9%) are oceanic. In other words, the offshore plankton samples contain about the same proportion of inshore and offshore fishes as the total fish fauna of the region. Of the 15 families occurring most frequently in the samples studied by Richards, 7-, Labridae, Scaridae, Bothidae, Serranidae, Congridae, Callionymi- dae-have inshore representatives. This also agrees with the relative numbers of inshore and offshore families in the total fauna. Inshore collections, however, present a much different picture. Our light col- lections contain large numbers of individuals, but these collections are overwhelm- ingly dominated by three groups; clupeids, blennioids, and gobioids. In 19 light samples taken in 1985 these three groups accounted for 50.1 %, 25.0% and 16.8% of the total numbers, respectively. Our collections contained large numbers of -sac (preflexion) larvae as well as intermediate stages and more advanced larvae, indicating that these fishes complete their life cycle in the immediate vicinity of the reef. These groups were also present in Richards' samples, but clupeids and blennioids were present only in small numbers: 6 occurrences of clupeids and 1 ofblennioids out of 109 samples. Gobiids, on the other hand, with 81 occurrences, ranked fourth in abundance and occurrences in Richards' Carib- bean data. Considering that the Oobiidae is the most speciose family in the fauna, with at least 95 species, this is not surprising. Other families in the light collections include , Haemulidae, 00- biesocidae, Pempheridae, Syndontidae, Ophidiidae, and others that we have not yet identified. At least two of our night collections each contain more specimens of gobiesocids than in all of Richards' offshore collections. Morphological Comparisons. - One of the striking characteristics of the fishes in our near-reef samples is that few of the specimens collected at lights have any of the conspicuous morphological specializations that are frequently seen in pelagic ichthyoplankton. To follow up on this observation we compared samples from four environments: bottom tows in a reef canyon, surface tows in the same canyon, the larvae attracted to a light placed near the canyon floor and two series of offshore net tows. We examined each apparent taxon for the presence of one or more of seven types of specializations. For the purposes of this discussion we recognize two distinct types of structural difference between larval and adult fishes. The first type includes stages in the development of features that characterize the adults (Fig. Ia, b). The changes in the structure of the caudal as the urostyle turns upward and the hypural plates form is an example. The development of fin rays and adult pigment patterns are others. We place the migration of the eye of in this category because it happens in all pleuronectiforms and is the only way the distinctive form of the adults can develop. SMITH ET AL.: INSHORE ICHTIiYOPLANKTON 435

f

g h

I mm

Figure I. Morphological characters of larval fishes: a, un specialized, unidentified blennioid ; b, postlarval gobioid without pigment; c, unidentified perciform with elongated dorsal spine; d, acanthurid with elongate fin spines and rhombic body shape; e, holocentrid with elongate head spines; f, myctophid with elliptical eye; g, astronesthid(?) showing trailing gut; h, gobiesocid with superficial dorsal pigment.

The second type consists of features that develop in the larval stages and dis- appear in the adult (Leis and Rennis, 1983). Since these features are only present during the planktonic phase of the life history it is reasonable to regard them as adaptations for planktonic existence. While such developmental stages could serve special functions in the larvae, there is no easy way to determine this without detailed study of the living larvae. Govoni et al. (1984) suggested multiple functions for the vexillum ofIarvaI Carapidae but at present we can only guess at the functions of most of these specializations in the majority of families. Nevertheless, the 436 BULLETIN OF MARINE SCIENCE, VOL. 41, NO.2, 1987 diversity of specializations and their occurrence in different and unrelated groups of fishes is convincing evidence that they are useful. More significantly, this diversity of specializations supports the notion that larval fishes have unique niches during their pelagic life, in spite of the apparent homogeneity of their open water environment. It is important to note that the occurrence of these special- izations does not always follow family boundaries, at least as fish taxnomy cur- rently is practiced. For example, dorsal spines are extremely elongate in the ser- ranid subfamily Epinephelinae but not at all elongated in the related Serraninae (Kendall, 1984) and the larvae of Myctophids are extremely diverse (Moser et aI., 1984). Since the interpretation of a particular condition as a developmental stage or as a larval specialization is subjective, we present our interpretations of the major types of larval specializations in some detail. If a feature is better developed in transformed juveniles or in adults than it is in the larvae, we consider the larval expression of the characteristic to be merely a stage in its development. Only if the condition is unique or is expressed in a hypertrophied condition in the larval stage do we regard it as a larval adaptation. In our tabulations we have excluded as juveniles individuals that have developed all of their adult features except the pigment patterns. ELONGATEFIN SPINES(Fig. lc, d). Perhaps the most common larval modification is the elongation of anterior elements. In its extreme form the ray or spine can be flexible and several times as long as the body and in some groups the spine itself bears appendages resembling the leaves of . In other groups of fishes the elongate larval spines are hard and characteristically spinulose al- though they may become smooth in the adult (Johnson and Keener, 1984). Elon- gate dorsal spines occur in many families and are especially prominent in some Serranidae, Carapidae, Bothidae, Pseudochromidae, and Balistoi- dea. Elongate anal fin spines are less widely distributed but are present in Acan- thuridae. Elongate pelvic spines often occur with elongated spines of the median . Like the dorsal spines, they frequently bear flaps of soft tissue or spinules. Pelvic spines are developed in Serranidae, Acanthuridae and others. Elongation of pec- toral or caudal rays, however, is so uncommon that we consider them as idio- syncratic structures that can be regarded as unique evolutionary experiments (autapomorphies). CRANIALARMATURE(Fig. Ie). Many open water larvae have characteristic elab- orations of the superficial bones of the top of the skull. Examples are the frontal bones in the lutjanid genus Symphysanodon, and the pterotics, supraoccipital and ethmoid region in the holocentrids (the so-called rhynchichthys larva). These elongate spines often are flattened, complex structures consisting of a central axis with opposing rows of spines connected by webs of bone. In the tholichthys stage of chaetodontids several head bones are expanded into massive superficial plates. The preopercle is a superficial lateral bone that bears spines or serrations in the adults of many groups of fishes and it is not surprising that the larvae of some forms should also bear spines. However, the degree of elongation is often many times that of the adult; in which case we interpret them as larval adaptations. In many groups the structure of the larval preopercular spine is similar to that of the projections on the other head bones-flattened with a central axis with branch spines connected by thin bone. Other head bones, including the opercle, subopercle, and interopercle, the lac- rimals, nasals, the bones of the lower jaw, and possibly others sometimes bear spines or serrations. SMITH ET AL.: INSHORE ICHTHYOPLANKTON 437

BODVSHAPE(Fig. Id). Most larval fishes differ from adults in their overall body shape and any attempt to determine whether a particular form is a planktonic specialization is bound to be subjective. Nevertheless, there are some body shapes, such as the stage of and acronurus of acanthurids, that are so different from the form of the adult that they must surely be adaptations for planktonic life. EXSERTEDHINDGUT(Fig. Ig). The pelagic larvae of some deep-sea fishes have trailing extensions of the hindgut. We list the condition as present if there is any protrusion beyond the ventral profile of the body, exclusive of the preanal fin fold. This characteristic is especially well developed in some Astronesthidae, Melanostomiatidae, and certain genera of Myctophidae. In our inshore bottom collection we recorded this character only in myctophid larvae where it was only slightly developed. It was well developed in the astronesthid larva from deep water. STALKEDEVES.The probable functions of stalked eyes in planktonic larvae have been discussed by Moser (1981) and by Weihs and Moser (1981). While the Idiacanthidae is perhaps the most extreme and best known example, there is considerable variation in the length of the stalks and it is sometimes difficult to determine the presence of stalks in damaged specimens. We consider the feature to be present if there is any indication of a constricted ocular stalk. We have a few specimens of elongated larvae that we suspect had stalked eyes but their eyes are missing and the condition of the rest of the specimens precludes definitive identification. These specimens are not included in our data. ELLIPTICALEVES(Fig. If). Larvae were classified as having elliptical eyes if one axis in the plane of the body surface was noticeably greater than another, dis- counting shrinkage and other distortion. In most larvae the horizontal axis of the eye was shorter than the vertical. The presence of elliptical eyes is not confined to oceanic pelagic larvae and even occurs in some freshwater fishes, but it does appear to be related to a midwater existence. DORSAL PIGMENT (Fig. Ih). Moser (1981) has pointed out that neustonic species tend to have numerous melanophores on the dorsal surface of the body. Presum- ably this is an adaptation to protect them against the bright sunlight in the surface waters. This adaptation is especially conspicuous in exocoetids, belonids, cory- phaenids and .

Occurrences of Specialized Larvae. - FLOODLIGHTCOLLECTIONS.The floodlight on the Hydrolab habitat attracted large numbers of fish larvae. In 1984, 14 sweeps yielded I to 1,474 larvae per tow (average 233.5). Much of the variability can be ascribed to the length of time the light was on before the sweeps were made. The lowest numbers oflarvae in the 1984 collections were in sweeps made immediately after the light was turned on, without allowing time for larval accumulation. In 1985, we made sweeps only after the light had been on for an hour or more and 19 samples contained 70,397 larvae or an average of 3,705 larvae per 10-minute sweep. The diversity of the light collections is low and they are dominated by clupeids (Jenkinsia), gobioids and blennioids, which together make up more than 87% of the total collection. All of these have unspecialized larvae. Other larvae included gobiesocids which have considerable dorsal pigment. This is the only specializa- tion we found in the larvae from the light collections. BOTTOMTow COLLECTIONS.We made 42 bottom tows in the Salt River Canyon in 1984 and 47 in 1985. Of the 89 tows, 53 were made during daylight hours and 36 were at night. 47% of the daylight tows and only 3% of the nighttime tows 438 BULLETIN OF MARINE SCIENCE, VOL. 41, NO.2, 1987

Table I. Occurrence of specialized larval characters

Hydrolab light Canyon floor Canyon surface Canyon offshore

Specialization No. % No. % No. % No. %

Elongated fin spines 0 0 I tr 3 2.1 260 15.3 Elongated head spines I tr 13 9.7 38 26.4 121 7.1 Modified body shape I tr I tr 2 1.4 8 0.5 Exserted gut 0 0 73 4.9 0 9 2 0.5 Stalked eyes 0 0 0 0 0 0 2 0.1 Elliptical eyes 0 0 129 7.1 0 0 299 17.6 Dorsal body pigment 67 0.1 4 0.2 15 10.4 51 3.0 Number of collections 19 28 10 14 Number of specimens 70,396 1,828 144 1,698 Average number of taxa per collection 8.9 5.4 5.6 17,1

contained no fish. Nighttime collections yielded an average of58.7 specimens per tow as compared with 6.74 specimens per tow in the daylight collections. Twenty- eight collections (1,828 specimens) were examined for the present study. Nearly all of the larvae from the bottom tows were unspecialized. 8% of the specimens had elliptical eyes and 4% had slightly exserted guts. The larvae with these spe- cializations were mostly myctophids that were collected at night in the deeper parts of the canyon. Less than 1% had elongated head spines, elongated fin rays or dorsal pigment and none had stalked eyes. SURFACETows IN SALTRIVERCANYON.Sixty surface and subsurface tows were made in 1984 and 1985. All but five contained fish larvae (average 14.4 larvae per tow). Specializations noted were: elongate fin spines in 9.7% of 144 specimens examined, elongate head spines in 6.7%, specialized body shape in 9.1%, elliptical eyes in 9.1% and dorsal pigment in 7.7%. Most of our surface tows were made in September but they appear to have roughly the same diversity as the few surface tows that were made at the same time as the bottom tows and the MOCNESS samples. OFFSHORECOLLECTIONS.The 14 NMFS samples contained a total of 1,698 fish larvae. Of these, 15% had elongate fin spines, 7.1% had hypertrophied head spines and 17.6% had elliptical eyes. Trailing guts, stalked eyes, and special body shapes each were present in less than 1% of the larvae. Included were members of deep-sea families such as myctophids, stomiatids, astronesthids, and melanostomiatids as well as inshore families such as holocen- trids, bothids, labrids, and scarids. These data are summarized in Table 1.

DISCUSSION Some families of reef fishes have specialized larvae; others have larvae that are unspecialized. Similarly, both morphologically specialized and unspecialized lar- val types are found in species that live in the open ocean. Although the different collecting methods used in the different preclude precise comparisons of the data sets, it is apparent that nearly all of the larvae from the light collections and the bottom tows in the Salt River Canyon are un specialized, while only a small fraction of the larvae taken in surface tows in the Salt River Canyon and a slightly larger but still only small proportion of the larvae taken over deep water have specializations. It is possible that some spe- SMITH ET AL.: INSHORE ICHTHYOPLANKTON 439 cialized larvae were also present close to the bottom but were missed by our sampling methods, but it is highly unlikely that disproportionately large numbers of blennies, gobies, and clupeids were present in the open sea samples reported on by Richards (1984). Several authors have commented on the advantage of planktonic life stages to organisms that live on coral reefs. Coral reefs occur as patches in an environment that is otherwise hostile to shelter-seeking fishes and the adults cannot migrate between remote patches. Since individual patches are subject to eventual destruc- tion, motile life stages are essential to reef-dwelling fishes. Johannes (1978) noted that peak spawning periods often occur in seasons when large scale currents are weakest but at times when the tidal currents provide maximum flushing of the larvae away from the littoral zone. It is apparent from the vast numbers oflarvae that concentrate at the Hydrolab floodlight that at least some of the larvae are good swimmers and capable of traveling considerable distances in response to a light source. We have not been able to determine where these larvae spend the daylight hours. Possibly they remain in the same area but are able to avoid our diver-towed collecting gear. Attempts to attract them to shelter during daylight by placing settlement traps at various distances from the light proved unsuccessful. Whether this was because of poor trap design or because they simply disperse through the during the day has not been determined. It is also possible that these larvae migrate en masse into deeper water close to the face of the drop-off during the day. Although some authors (Kendall, 1979) have suggested that elongated fin and cranial spines serve as protection against , our observation that the larvae that gather at the underwater lights generally lack strong spines would seem to argue against this hypothesis since the greatest concentration of predators is also close to the reef and many predators such as cardinal fishes are active at night. Whether or not the spines serve a protecive function, it would appear that the presence of protruding body parts would interfere with the swimming ability of the larvae and that whatever advantage such structures confer must be at the expense of mobility. The result is that highly specialized larvae are unable to avoid being carried along with the currents. The difficulty of identifying most of our larvae to species precludes detailed analysis but at present it appears that there is no reason to suspect that fish larvae in open-water collections are not "randomly" distributed. Such collections appear to reflect the relative abundance of shore-dwelling and open-water families of fishes known to occur in the Caribbean. The larvae of some reef-dwelling families such as gobies, labrids and scarids are widely distributed in the upper 200 m of the open sea. These families have unspecialized larvae but the epinepheline ser- ranids, which are also moderately common in the offshore collections, have highly specialized larvae. Thus, open-water samples contain both specialized and un- specialized larvae of inshore fishes as well as the larvae of offshore species. Collections from close to the reef, however, have few specialized larvae and few representatives of offshore families; one exception is the Myctophidae, which is the most speciose open water family in the region and whose members make dramatic vertical migrations daily. Therefore, we suggest that among inshore fish species, there is a distinctive assemblage of morphologically unspecialized larval stages that generally remain close to the reef. We submit that this strategy of avoiding open water currents and long distance transport is fundamentally different from the passive transport that is commonly assumed for larval fishes. 440 BULLETINOFMARINESCIENCE.VOL.41. NO.2. 1987

ACKNOWLEDGMENTS

This study was partally supported by the National Oceanic and Atmospheric Administration's National Undersea Research Program, which maintained the Hydrolab facility and granted us the use of it. We thank the staff of that facility, especially Drs. S. Williams and M. L. Coulston, R. Rounds, Dr. W. Shane, B. Nyden, R. Berey and R. Campagna. The Hydrolab program is administered through the West Indies Laboratory of Fairleigh Dickinson University, which provided accommodations and support during our surface studies as well as during the Hydrolab missions. The MOCNESS samples collected by the NMFS were presented to the West Indies Laboratory by D. E. Hoss and made available to us through the courtesy of Dr. J. Ogden, director of the laboratory. Travel and field expenses were provided by the Nixon Griffis Foundation, the National Science Foundation and the Smithsonian Institution. The drawings oflarval fishes are by N. Stem. This is contribution Number 165 from NOAA National Undersea Research Program.

LITERATURE CITED

Govoni, J. J., J. E. Olney, D. F. Markle and W. R. Curtsinger. 1984. Observations on structure and evaluation of possible function of the vex ilium in larval Carapidae (Ophidiiformes). Bull. Mar. Sci. 34: 60-70. Johannes, R. E. 1978. Reproductive strategies of coastal marine fishes in the tropics. Environ. BioI. Fish. 3: 65-84. Johnson, G. D. and P. Keener. 1984. Aid to identification of American larvae. Bull. Mar. Sci. 34: 106-134. Kendall, A. W., Jr. 1979. Morphological comparisons of North American sea bass larvae (Pisces: Serranidae). U.S. Dept. Comm. NOAA Tech. Rept. NMFS Circ. 428. 50 pp. ---. 1984. Serranidae: development and relationships. Pages 499-510 in H. G. Moser, W. J. Richards, D. M. Cohen, M. P. Fahay, A. W. Kendall, Jr., and S. L. Richardson, eds. Ontogeny and systematics of fishes. American Society of IChthyologists and Herpetologists, Special Publi- cation I. Leis, J. M. 1983. larvae (Labridae) in the east Pacific barrier. Copeia 1983: 826-828. ---. 1986. Vertical and horizontal distribution of fish larvae near coral reefs at Lizard Island, Great Barrier Reef. Mar. Bio. 90: 505-516. --- and D. S. Rennis. 1983. The larvae of Indo-Pacific coral reef fishes. New South Wales University Press, Sydney; University of Hawaii Press, Honolulu. 269 pp. Lobel, P. S. and A. R. Robinson. 1986. Transport and entrapment offish larvae by ocean mesoscale eddies and currents in Hawaiian waters. Deep-Sea Research 33: 483-500. McFarland, W. N. and J. C. Ogden. 1985. of young coral reef fishes from the plankton. The Ecology of Coral Recfs. Symposium Series for Undersea Research 3: 37-51. Moser, H. G. 1981. Morphological and functional aspects of marine fish larvae. Pages 90-131 in R. Lakser, ed. Marine fish larvae morphology, ecology, and relation to fisheries. University of Wash- ington Press. --, E. H. Ahlstrom and J. R. Paxton. 1984. Myctophidae: development. Pages 218-239 in H. G. Moser, W. 1. Richards, D. M. Cohen, M. P. Fahay, A. W. Kendall, Jr., and S. L. Richardson, eds. Ontogeny and systematics of fishes. American Society of Ichthyologists and Herpetologists, Special Publication I. Richards, W. J. 1984. Kinds and abundances offish larvae in the Caribbean Sea and adjacent areas. NOAA Tech. Rept. NMFS SSRF-776: vi + 54. Weihs, D. and H. G. Moser. 1981. Stalked eyes as adaptation toward more efficient foraging in marine fish larvae. Bull. Mar. Sci. 31: 31-36.

DATEACCEPTED: November 3, 1986.

ADDRESS: (C.L.S. and L.S.) The American Museum of Natural History, Central Park West at 79th Street, New York, New York 10024; (J.C.T.) National Museum of Natural History, Smithsonian Institution, Washington, D.C. 20560.