Pretransitional analogues:
Pretransitional larvae (mostly-unmarked stage, usually from 12-17 mm SL) can be separated from the other regional snappers by the dorsal-fin-ray count. In addition, the third anal-fin spine is about the same size as the second, unlike the Lutjanus species where the second anal-fin spine is distinctly stouter and usually longer. Additional useful distinguishing features include the dorsal and anal-fin spines relatively slender (shared with L. cyanopterus and L. analis), the second to fifth dorsal-fin spines about the same length, the anal-fin spines without prominent anterior serrations (vs. L. griseus, L. apodus and L. jocu), no lateral spot or bars, and a thin stripe of small surface melanophores extending forward along the lateral midline from the center of the caudal peduncle. The occasional individual has at most one or two melanophores at the base of the lowest of the upper caudal-fin segmented rays (vs. several in L. synagris and L. mahogoni).

Transitional stage:
Transitional O. chrysurus larvae develop a mostly-uniform scattering of small melanophores on the body. Early in transition, a line of fine surface melanophores extends forward from the caudal peduncle along the lateral midline.

Transitional analogues:
In addition to the fin-ray counts and the similar second and third anal-fin spines, transitional O. chrysurus larvae can be distinguished by the absence of spots and bars and the development of the characteristic thin line of small melanophores along the lateral midline.

Juveniles:
Juvenile O. chrysurus develop a pale midline lateral stripe (yellow in live specimens).

Juvenile analogues:
The absence of a lateral spot or bars and a yellow midline stripe is diagnostic.

Distinguishing the larvae and juveniles of the numerous Lutjanus species in the region can be difficult since many share the basic body form as well as most fin-ray counts. Fortunately, two common species, both with a lateral spot, do separate out by meristics: L. mahogoni and L. synagris have only twelve vs. the typical 14 dorsal-fin soft rays for the genus. Beyond this, distinctions can be difficult since pre-transitional larvae often have few identifying markings. It is likely that many pre-transitional snapper larvae will require molecular identification, with equipment leasing for DNA sequencing for species identification. Transitional and juvenile snappers can also share many of the basic markings that later distinguish the species (such as lateral spots, incipient bar patterns, and eye stripes). This pattern of earlier stages sharing characters that later diverge is commonly seen among reef fishes.

The spot snappers

The three shallow-water spot snappers (the Lane Snapper L. synagris, Mahogany Snapper L. mahogoni, and Mutton Snapper L. analis) are easily confused as larvae and juveniles. Unlike most fishes, these snappers converge even more in appearance after they settle than in the transitional stages. Notably, the relative dorsal-fin spine lengths and various spot and bar configurations that separate species well at transition can overlap to some degree as small juveniles. Subtle color-pattern differences are key to separating the larger juveniles. The series below shows transitional recruits captured on their first few days on the reef, when they can still be relatively easily distinguished.

The barred snappers

There is a great deal of individual variation in the marking patterns of transitional larvae and recruits of the barred snappers (the Gray Snapper L. griseus, Schoolmaster Snapper L. apodus, and Dog Snapper L. jocu). These snappers can all display stripes and/or bars or uniform speckling to some degree immediately after settlement and only cleanly diverge a week or two after settlement. For example, immediately after settlement some Gray Snappers can show the vertical bars characteristic of Schoolmaster Snappers. However, on Gray Snappers the bars tend to fade near the anal fin (see photo below). Similarly, some Gray Snappers are uniformly speckled before they develop their characteristic striping and thus look similar to newly recruited Dog Snappers, however the latter typically have finer speckles. Some individuals can appear intermediate and would require DNA sequencing. Nevertheless, the vast majority of newly-settled snappers, even those of this difficult clade, can be identified to species using the characters discussed below.

The deep snappers

DNA sequence matching on my specimens has clarified the identification of the late-stage larvae of the shallow-water snappers of the region. The deeper-water species, L. buccanella, L. campechanus, and L. vivanus, however, await more comprehensive sampling for a similarly complete treatment.

Pretransitional mostly unmarked stage, usually from 13-19 mm SL:
Body: Pretransitional larvae develop a row of melanophores on the body near the base of the dorsal fin, first along the pterygiophores supporting the soft dorsal fin (starting between the second and sixth rays) and then extending below the spinous portion as a few spots between the seventh and eighth spines and the ninth and tenth spines. As development continues, the row of melanophores below the dorsal fin fills in and extends forward to the level of the third spine (the base of the last three soft rays remain unmarked well into transition). On the caudal peduncle, melanophores line the dorsal and ventral midlines and, at the lateral midline, there is a row of deep melanophores along with a few scattered surface melanophores. One or two discrete internal melanophores lie well below the pterygiophores of the last few anal-fin rays.
Head: Melanophores on the head consist of dense patches overlying the brain and on the surface braincase. There are small melanophores around the tips of the upper and lower jaws. The opercular area is covered in iridescence extending down to the pelvic-fin insertion. The inner cleithral surface of the gill cavity is speckled with large melanophores and there are internal melanophores lining the dorsal aspect of the swim bladder and peritoneum extending down to the vent and overlain by a silvery camouflage layer.
Fin Spines: The dorsal and anal-fin spines are relatively stout, usually with some internal reticulations. The anal-fin spines do not show anterior serrations. The second dorsal-fin spine is shorter than the third.
Fins: Small melanophores speckle the distal two-thirds of the dorsal-fin-spine membranes. On the caudal fin there is a vertical line of melanophores at the base of some of the upper as well as most of the lower segmented rays. A row of melanophores develops along the anal-fin base, one at the base of each soft fin ray.

Pretransitional analogues:
Pretransitional larvae of the two 12-dorsal-rayed snappers are best distinguished by the relative lengths of the second and third dorsal-fin spines: in L. synagris the second dorsal-fin spine is shorter than the third spine vs. longer (pretransitional larvae) to about equal (late in transition) to the third spine in L. mahogoni. The two 12-dorsal-rayed snappers can be separated from the 14-dorsal-rayed snappers by the dorsal-fin-ray count, as well as having melanophores at the bases of the upper as well as the lower caudal-fin segmented rays at this early stage (sometimes shared by L. analis). The dorsal and anal-fin spines of larval L. speciessynagris are also stouter than in L. analis, L. cyanopterus, and Ocyurus chrysurus. L. synagris larvae at this stage also do not have distinct anterior serrations persisting on the anal-fin spines as do L. griseus, L. apodus and L. jocu (occasional individuals do have a few remnant serrations). Almost all pretransitional L. synagris captured over the reef already show the lateral spot, unlike L. analis and the barred species.

Transitional stage:
Transitional L. synagris larvae develop a prominent lateral spot early, usually with the lateral line running through the lower third of the spot. Iridescent bars form at each side of the lateral spot, bracketing the black spot up to the base of the dorsal fin. The dark bar anterior to the spot curves away, forming a bracket. An additional set of thin iridescent stripes develops along the lower side alternating with thin stripes of melanophores (in life the pale stripes are yellow).

Transitional analogues:
The main difference between the two 12-rayed species is that the second dorsal-fin spine is shorter than the third in L. synagris vs. longer or equal in L. mahogoni (and L. analis). The location of the lateral spot usually differs, although some individuals do overlap: the lateral line usually runs through the lower third of the spot in L. synagris and through the middle of the spot in L. mahogoni. A consistent difference is that on L. synagris the bar forward of the lateral spot is not straight; it clearly curves away and brackets the spot, while in L. mahogoni (and L. analis) the bar slopes evenly down from the base of the dorsal fin across the body. Transitional larvae of L. synagris always have a lateral spot, then they subsequently develop bars (vs. bars, then a spot on L. analis). Some transitional L. analis with a lateral spot can look remarkably similar to L. synagris, however in the latter the spot is large and expands the bar, vs. staying within the bar in L. analis. Furthermore, transitional L. analis have three more distinct bars on the body behind the lateral spot while these bars are usually undeveloped on transitional L. synagris. On new recruits, the iridescent stripes (note, not the bars) along the lower side of the body characteristic of L. synagris are absent in L. analis.

Juveniles:
Juvenile L. synagris have a lateral spot with the lateral line running through the lower third of the spot (or sometimes below the spot) and about six to eight thick yellow stripes below the lateral line in the bar anterior to the spot.

Juvenile analogues:
For juveniles less than 25 mm SL the relative dorsal-spine-length characters separate juvenile L. synagris from L. mahogoni and L. analis. They all have yellow stripes as juveniles, although the stripes become thick and more prominent on later juvenile L. synagris and thinner and less conspicuous on juvenile L. mahogoni. Furthermore, in juvenile L. mahogoni the lateral spot is often elongated (in width) and the lateral line runs through the middle of the spot vs. a rounded or vertically elongated spot with the lateral line running through the lower third (or below the spot) in L. synagris. One of the more reliable methods to distinguish L. synagris from L. analis as larger juveniles is the number of yellow stripes below the lateral line in the bar anterior to the spot: in L. analis the stripes tend to bifurcate into paired thin stripes, from 9-12, while in L. synagris the stripes remain thick and number 6-8. As they get larger, L. analis develop a pointed outline to the anal fin while L. synagris retains a rounded outline.

Pretransitional mostly-unmarked stage, usually from 17-21 mm SL:
Body: Pretransitional larvae develop a row of melanophores on the side of the body near the base of the dorsal fin. The row starts as small melanophores, often lined up along the anterior aspect of the pterygiophores below the soft dorsal fin. The row fills in under the soft dorsal fin and extends forward just below the spinous portion of the fin, first as a few spots beneath the third to fifth spines and the seventh to ninth, and then filling in up to the level of the third dorsal-fin spine. The two rows on each side of the dorsal fin merge into a line of melanophores lining the dorsal midline of the caudal peduncle (usually made up of a short row of deeper and larger larval melanophores overlain by a band of smaller melanophores). A similar line develops along the ventral midline of the caudal peduncle extending forward and ending just before a single large melanophore underlying the pterygiophores of the last anal-fin rays. There are a few deep melanophores at the end of the lateral midline of the caudal peduncle and a fine speckling of small melanophores around the central caudal peduncle.
Head: Melanophores on the head consist of dense patches overlying the brain and on the surface braincase. There are small melanophores around the tips of the upper and lower jaws. The opercular area is covered in iridescence extending down to the pelvic-fin insertion. The inner cleithral surface of the gill cavity is speckled with large melanophores and there are internal melanophores lining the dorsal aspect of the swim bladder and peritoneum extending down to the vent and overlain by a silvery camouflage layer.
Fin Spines: The dorsal and anal-fin spines are relatively stout, usually with some internal reticulations. The tip of the second dorsal-fin spine often curves slightly upward (the preopercular spine often curves slightly upward as well). The second dorsal-fin spine is usually longer than the third and typically the tip overlaps or extends beyond the tip of the third. The dorsal-fin spines then become progressively and evenly shorter such that the profile of the spinous tips forms a straight downward-sloping line. The anal-fin spines do not show anterior serrations (a rare individual has small remnant serrations). The second anal-fin spine is longer than the third, but the tips are closely-approximated or the third extends slightly farther back than the tip of the second when folded down.
Fins: Melanophores are prominent along most of the length of the membrane just behind the second dorsal-fin spine and are concentrated on the membrane tag extending beyond the spine. Smaller melanophores speckle the outer third of all of the subsequent membranes of the spinous portion of the dorsal fin. On the caudal fin there are a few small melanophores at the base of some of the upper as well as most of the lower segmented rays. A row of melanophores develops along the anal-fin base, one at the base of each anal-fin-ray membrane, often including the membrane behind the third-spine.

Pretransitional analogues:
Pretransitional larvae of the two 12-dorsal-rayed snappers are best distinguished by the relative lengths of the second and third dorsal-fin spines: in L. mahogoni the second dorsal-fin spine is longer than the third spine with the tip often overlapping the tip of the third vs. shorter than the third spine in L. synagris. L. mahogoni can be separated from most of the 14-dorsal-rayed snappers by the dorsal-fin-ray count, as well as by having melanophores at the bases of the upper as well as the lower caudal-fin segmented rays at this early stage (sometimes shared by L. analis). The dorsal and anal-fin spines of larval L. mahogoni are also stouter than in L. analis, L. cyanopterus, and Ocyurus chrysurus. L. mahogoni larvae at this stage also do not have distinct anterior serrations persisting on the anal-fin spines as do L. griseus, L. apodus and L. jocu. Almost all pretransitional L. mahogoni captured over the reef already show at least a few melanophores at the lateral spot, unlike L. analis and the barred species.

Transitional stage:
Transitional L. mahogoni larvae develop a prominent lateral spot early, usually with the lateral line running through the middle of the spot (although some individuals clearly have the line running through the lower third). The spot is wider than the bar, distinctly expanding the outline of the bar. Larval L. mahogoni often have an upturned preopercular spine, but this character is not consistent later.

Transitional analogues:
The main difference between the two 12-rayed species is that the second dorsal-fin spine is longer than the third (sometimes about equal) for L. mahogoni (and L. analis) vs. shorter in L. synagris and this difference persists in juveniles up to 25 mm SL. The location of the lateral spot usually differs, although some individuals do overlap: the lateral line usually runs through the middle of the spot in L. mahogoni and through the lower third of the spot in L. synagris (variable in transitional L. analis). In addition, on L. synagris the bar forward of the lateral spot is not straight; it clearly curves away and brackets the spot. Transitional larvae of L. mahogoni always have a lateral spot, then they subsequently develop bars (vs. bars, then a spot on L. analis). Some transitional larvae and early recruits of L. analis after they develop the lateral spot can look remarkably similar to L. mahogoni. Other than the soft dorsal fin-ray counts, the species can be separated by some marking differences: the spot is larger and more elongated in L. mahogoni, expanding the bar from which it develops, while in L. analis the spot is only as wide as the bar from which it forms. Furthermore, transitional L. analis have three more typically distinct bars on the body behind the lateral spot while these bars are usually undeveloped on transitional L. mahogoni.

Juveniles:
Juvenile L. mahogoni have an elongated lateral spot with the lateral line running through the middle of the spot.

Juvenile analogues:
Juveniles of L. mahogoni can be distinguished by the lateral-spot location, i.e. the lateral line through the middle of the spot in L. mahogoni and usually through the lower third in L. synagris and L. analis. Notably, the lateral spot is often elongated (in width) in juvenile L. mahogoni vs. rounded and within the bar in L. analis. The relative dorsal-spine-length differences persist in juveniles up to 25 mm SL. All have yellow stripes as juveniles, although the stripes become thinner and less conspicuous on juvenile L. mahogoni and thicker and more prominent on later juvenile L. synagris. The preopercular outline is not diagnostic in young stages, with L. mahogoni larvae and juveniles not showing the notch pattern that occurs later.

Pretransitional mostly-unmarked stage, usually from 13-18 mm SL:
Body: A thin line of melanophores develops on each side just below the base of the spinous dorsal fin, from the third to fifth and the sixth to eighth spines (leaving an unpigmented dorsal midline along the base of the fin). The rows continue along the base of the soft dorsal fin on the outer pterygiophore segments and then merge into a single band of melanophores lining the dorsal midline of the caudal peduncle. There are a few deep melanophores at the end of the lateral midline on the caudal peduncle. Along the ventral midline of the caudal peduncle there is a single melanophore just forward of the first procurrent caudal-fin ray, often followed by several more toward the last anal-fin ray.
Head: Melanophores on the head consist of a dense patch overlying the brain and on the surface braincase. There are small melanophores at the tip of the upper jaw and a small patch extends upward along the snout. The lower jaw is mostly unmarked, with only a few small melanophores near the tip. The opercular area is covered in iridescence extending down to the pelvic-fin insertion. The inner cleithral surface of the gill cavity is speckled with large melanophores and there are internal melanophores lining the dorsal aspect of the peritoneum extending down to the vent and overlain by a silvery camouflage layer.
Fin Spines: The median-fin spines are relatively slender, without prominent internal reticulations and lacking anterior serrations. The second dorsal-fin spine is longer than the third and the subsequent spines are progressively shorter. The second anal-fin spine is only slightly longer than the third and the tip usually does not reach farther back than the tip of the third.
Fins: Melanophores are present along most of the length of the membrane just behind the second dorsal-fin spine and then near the outer edges of most of the subsequent membranes of the spinous portion of the dorsal fin. There are melanophores between the bases of the lower central caudal-fin segmented rays and often a few smaller ones between the bases of the lowest upper caudal-fin segmented rays. The anal fins often have no markings but a row of melanophores usually develops during transition (on the membranes near the base of each soft ray). The pelvic fins develop melanophores along the full-length of the first two soft rays and membranes.

Pretransitional analogues:
Pretransitional larvae (mostly-unmarked, usually from 13-18 mm SL) have relatively slender and smooth dorsal and anal-fin spines, without the prominent internal reticulations and anterior serrations found in L. griseus, L. apodus, and L. jocu. In addition, amongst the regional Lutjanus, only L. analis and L. cyanopterus often have no melanophores along the base of the anal-fin rays before transition. Pretransitional L. analis also share the relatively slender and smooth spines (and snout melanophores) with L. cyanopterus, but can be distinguished by having a distinctly-narrower caudal peduncle, melanophores along the full-length of the pelvic-fin membranes or absent (vs. on the outer third of the longest pelvic-fin membranes), and the tip of the second anal-fin spine is near the tip of the third (vs. the tip of the second usually extending well past the tip of the third in L. cyanopterus).

Transitional stage:
Transitional L. analis larvae develop distinct bars of small melanophores slanted down and to the rear. The space between the seven bars is typically iridescent and usually not speckled during transitional stages. A lateral spot then develops in the fourth bar at the level of the lateral line, intensifying within the confines of the bar of melanophores (without expanding the outline of the bar).

Transitional analogues:
In contrast to transitional L. analis, the bars are vertical in L. apodus, L. jocu, and L. cyanopterus; the bar originating at the mid-soft-dorsal fin slants down to meet the last anal-fin ray in L. analis vs. to the mid-anal fin in the vertically-barred species. Transitional L. analis often do not develop the characteristic lateral spot until past the transitional stage (vs. early and isolated spot appearance in the 12-rayed snappers). When the spot develops, it can be difficult to separate L. analis from L. synagris and L. mahogoni. A reliable difference is in the relative length of the second dorsal-fin spine: well shorter than the third in L. synagris vs. longer or equal in transitional L. analis and L. mahogoni. The marking patterns do diverge as the spot develops: on L. analis recruits the spot notably forms within the bar, without expanding the outline of the bar as it does on the 12-rayed snappers. In addition, on L. synagris the bar forward of the lateral spot is not straight; it clearly curves away and brackets the spot. Transitional L. analis also have three typically distinct bars on the body behind the one with the lateral spot while these bars are usually indistinct on transitional larvae of the others.

Juveniles:
Juvenile L. analis have a distinct round lateral spot contained within the confines of a dark bar, with the lateral line usually running through the lower third and more than eight yellow stripes on the body below the lateral line in the bar anterior to the spot.

Juvenile analogues:
Juvenile L. analis can be separated from the other shallow-water species with bars and a lateral spot by the 14 soft dorsal-fin rays (vs. 12 in L. synagris and L. mahogoni). Larger juveniles of L. analis converge in appearance with the other spotted snappers, often sharing the lateral spot location (spot size and location can be variable), the striping on the side of the body, and even the relative dorsal-fin spine lengths (after 25 mm SL). One of the more reliable methods to distinguish the species as larger juveniles is the number of yellow stripes below the lateral line in the bar anterior to the spot: in L. analis the stripes tend to bifurcate into numerous thin stripes, from 9-12, while in L. synagris the stripes remain thick and number 6-8. L. mahogoni juveniles have inconsistent yellow stripes, but their lateral spot is typically larger and elongated in width compared to that of L. analis. As they get larger L. analis develop a pointed outline to the anal fin while the other species retain a rounded outline.

Pretransitional mostly-unmarked stage, usually from 10-13 mm SL:
Body: Pretransitional larvae have two patches of melanophores on the body below the dorsal fin: under the last two dorsal-fin spines and first dorsal-fin soft rays and then under the middle of the soft dorsal fin. There is a band of surface melanophores along the anterior half of the dorsal midline of the caudal peduncle and full-length along the ventral midline of the caudal peduncle, extending forward and ending just before a single large melanophore underlying the pterygiophores of the last anal-fin rays. A patch of surface melanophores develops on the caudal peduncle filling in progressively from ventral to dorsal in a mostly uniform pattern, without a distinct clear bar anteriorly on the lower half of the caudal peduncle. There are a few deep melanophores at the end of the lateral midline of the caudal peduncle.
Head: Melanophores on the head consist of a patch overlying the brain and on the surface braincase and around the tip of the upper jaw; at the tip of the lower jaw there are either no melanophores or distinctly fewer than at the tip of the upper jaw. The opercular area is covered in iridescence extending down to the pelvic-fin insertion. The inner cleithral surface of the gill cavity is speckled with large melanophores and there are internal melanophores lining the dorsal aspect of the peritoneum extending down to the vent and overlain by a silvery camouflage layer.
Fin Spines: The dorsal and anal-fin spines are relatively stout, with prominent internal reticulations. There are fine serrations along the anterior aspect of the anal and dorsal-fin spines at this stage, typically persisting into transition in this species.
Fins: Melanophores on the dorsal-fin membranes are concentrated between the third and eighth spines, present on the dorsal midline at the base of the membrane and extending halfway or two-thirds up the membranes. The dorsal-midline melanophores are often present from the second to the tenth dorsal-fin spine bases. On the anal fin, there are melanophores on the lower half of the membranes between the anal-fin spines and about half-way up the second anal-fin spine. They continue on the lower half of the membrane between the last spine and the first ray and the next membrane, followed by melanophores only at the base of the membrane for the next few rays. Melanophores are concentrated below the pterygiophores of the last two or three rays (often as one conspicuous large melanophore) where they join the row along the ventral midline of the caudal peduncle. There are often a few melanophores along the proximal portion of the segmented caudal-fin rays in two places: between the bases of the lower-central rays and along the lowest two or three rays, the latter often extending in a line out along the rays.

Pretransitional analogues:
Pretransitional larvae (mostly-unmarked stage, usually from 10-13 mm SL) are separated from many other Lutjanus by having distinct serrations persisting on the anterior profile of the anal and dorsal-fin spines (but shared by L. apodus and L. jocu). The L. griseus larval type is distinguished from the L. apodus and L. jocu types at this stage by having the spinous-dorsal-fin melanophores mostly on the proximal two-thirds of the membranes with some touching the dorsal midline around the insertion of the spines (vs. melanophores concentrated on the distal portion of the membranes and sparing the dorsal midline at the base of most of the dorsal-fin spines). Additional features separating lightly marked L. griseus from L. apodus are a more uniform melanophore scattering on the lower caudal peduncle (vs. concentrating as a bar at the posterior half), melanophores along the anterior half of the dorsal midline of the caudal peduncle (vs. a short line usually less than a third of the peduncle length), more melanophores on the tip of the upper than lower jaws, and relatively lightly or unmarked lower head and pelvic fins (even on heavier-marked larvae).

Transitional stage:
Transitional larvae of L. griseus develop a relatively uniform scattering of melanophores on the body, usually with some indistinct light bars on the upper side of the body. The lower half of the caudal peduncle is uniformly speckled. Melanophores extend from the dorsal midline out to about two-thirds of the spinous-dorsal-fin membranes. A distinct stripe extends from the eye forward to the tip of the upper jaw and two stripes develop behind the eye and diverge. The tip of the lower jaw, the ventral half of the head and the pelvic fins are lightly speckled in most transitional larvae. Transitional recruits are mostly uniformly speckled; when indistinct bars are present they fade out on the lower body, especially near the anal fin. Many show a pattern of large blotchy melanophores over a finer speckling. The large melanophores disappear in small juveniles and are replaced by a pattern of stripes.

Transitional analogues:
Transitional L. griseus larvae tend to have a relatively uniform scattering of melanophores on the body with no lateral spot, distinguishing them from the other spotted or barred species. Furthermore, transitional L. griseus larvae usually retain anterior serrations on the anal-fin spines separating them from most other snappers (except some L. apodus and L. jocu). Some transitional L. griseus may have indistinct bars, but these are typically limited to the upper half of the body vs. obvious full-body bars in larval L. apodus and L. analis. Especially on early-transitional stages, L. griseus have a lightly-marked lower jaw and head below the level of the eye (vs. often heavily spotted in the latter species), and pelvic fins mostly unpigmented (vs. covered in melanophores). The other uniformly-marked transitional snappers comprise L. jocu and L. cyanopterus. Transitional L. cyanopterus have a quite different body shape with a narrower and longer body and a wider caudal peduncle (relative to body depth). Transitional recruits of L. jocu can appear quite similar to transitional L. griseus, but in L. jocu the thin indistinct light bars persist without any development of body stripes and the body is more finely speckled.

Juveniles:
Juvenile L. griseus are overall dusky with a prominent dark stripe through the eye and a pattern of thin parallel dark lines across the body, most distinctly below the lateral line. The stripes are characteristically made up of rows of individual dark-spotted scales. Some individuals show an indistinct bar pattern, but it is limited to the upper half of the body.

Juvenile analogues:
L. griseus juveniles lack the lateral spot of many other snapper juveniles and do not show the prominent bars of juvenile L. apodus. They are wider-bodied with a narrower caudal peduncle than juvenile L. cyanopterus. L. griseus juveniles can appear similar to some of the more uniformly-marked early juvenile L. apodus and L. jocu, however the thin dark stripes on the side of the body and the dark stripe through the eye intensify in L. griseus, while in juvenile L. jocu the dark stripe through the eye becomes less prominent and the blue line below the eye intensifies and juvenile L. apodus rapidly develop prominent bars.

Pretransitional mostly-unmarked stage, usually from 10-15 mm SL:
Body: Pretransitional larvae can have a few melanophores on the body just below the dorsal fin base where the future bars will develop: at the mid-spinous dorsal fin, the end of the spinous dorsal fin and under the mid-soft dorsal fin. There is a patch of melanophores along the anterior third of the dorsal midline of the caudal peduncle and a full-length band of melanophores along the ventral midline of the caudal peduncle extending forward and ending just before a single large melanophore underlying the pterygiophores of the last anal-fin rays. A bar pattern begins on the lower caudal peduncle as a patch without melanophores between two bars. There are a few deep melanophores at the very end of the lateral midline of the caudal peduncle.
Head: Melanophores on the head consist of a patch overlying the brain and on the surface braincase and small melanophores around the tips of both the upper and lower jaw (in similar numbers). The opercular area is covered in iridescence extending down to the pelvic-fin insertion. The inner cleithral surface of the gill cavity is speckled with large melanophores and there are internal melanophores lining the dorsal aspect of the peritoneum extending down to the vent and overlain by a silvery camouflage layer.
Fin Spines: The dorsal and anal-fin spines are relatively stout, with prominent internal reticulations. There are fine serrations along the anterior aspect of the anal-fin spines at this stage, but disappearing during transition.
Fins: Melanophores on the dorsal-fin membranes are concentrated between the third and eighth dorsal-fin spines, predominantly on the distal half of the fin-ray membranes and typically sparing the membranes adjacent to the base of the fin. Some individuals have melanophores spreading down to meet the dorsal midline, but only behind the fourth and fifth spines and later the ninth and tenth spines (at the site of the future dark bars on the body). On the anal fin, there are melanophores along the base of the spines and membranes, spreading almost half-way up the second and third anal-fin spines. There are melanophores on the lower portion of the membrane between the last anal-fin spine and the first ray and the next membrane or two, followed by melanophores at the base of the membrane for the next few rays. There can be a few melanophores between the bases of the uppermost of the lower segmented caudal-fin rays and also on the lowest two or three segmented rays, often extending out along the rays.

Pretransitional analogues:
Pretransitional larvae (mostly-unmarked stage, usually from 10-15 mm SL) are separated from some other Lutjanus by having distinct serrations persisting on the anterior profile of the anal and dorsal-fin spines (but shared by L. griseus and L. jocu). L. apodus larvae are distinguished from the L. griseus type at this stage by having the dorsal-fin membrane melanophores concentrated on the distal portion of the membranes, only a small patch on the anterior third of the dorsal midline of the caudal peduncle, usually an incipient bar pattern on the lower caudal peduncle, similar numbers of melanophores on the tip of the upper and lower jaws, and often pigmentation along the longest pelvic-fin membrane. It is likely that pretransitional L. jocu cannot be separated from L. apodus.

Transitional stage:
Early transitional L. apodus develop a pattern of bars on the body, beginning at the lower caudal peduncle where two dark bars first separate and then bars progressively develop from the caudal peduncle anteriorly. Each bar starts below the base of the dorsal fin and extends down with development. The mid-body bars begin with three patches of melanophores: the first under the fourth to sixth dorsal-fin spines, the second under the last two dorsal-fin spines and first dorsal soft rays and the third under the middle of the soft dorsal fin. Melanophores are limited to the outer half of the spinous-dorsal-fin membranes at first, but progressively extend down during transition. Before any stripes develop on the head, the tips of the upper and lower jaws are similarly speckled with small melanophores. Even on lightly-marked transitional larvae, there are some small melanophores on the thorax and the pelvic fin membranes. Early transitional larvae have serrations on the anterior aspect of the first two anal-fin spines, but these are usually lost midway through transition. Late transitional larvae have melanophores covering much of the body, but now the bars are made up of alternating areas of smaller and larger melanophores. The lower caudal peduncle at this stage has filled-in with melanophores and no longer has bars separated by non-pigmented skin. By this point, melanophores have advanced down the spinous-dorsal-fin membranes and do reach the base where they merge with the melanophores of the darker bars. On the head, a stripe develops between the eye and the tip of the upper jaw and two stripes diverge behind the eye. Small melanophores fill in and uniformly speckle the cheek, operculum, and thorax as well as the pelvic fins.

Transitional analogues:
Transitional L. apodus larvae develop bars on the body with no lateral spot, distinguishing them from the spotted species. In the early stages of transition, L. apodus larvae can be separated from L. griseus by having incipient melanophore bars forming on the lower caudal peduncle (vs. uniform) and having melanophores mostly on the distal half of the spinous-dorsal-fin membranes (vs. proximal and base). Late transitional L. apodus larvae differ from L. griseus by having distinct vertical bars of larger melanophores on the body vs. uniform speckling over the upper body (and lighter over the lower half of the head and abdomen) or indistinct bars at most on the upper half of the body, numerous melanophores speckling the cheek, thorax, and pelvic fins (vs. those areas relatively lightly-marked). Transitional recruits of L. jocu can overlap in appearance and can show a similar bar pattern to that of transitional L. apodus, although the lighter bars are narrower and the bar pattern becomes less distinct with development. There is also some overlap in appearance when both have a mostly-uniform speckling pattern, although uniform L. apodus have large melanophores and L. jocu have a fine speckling of melanophores (for example, in the space below the eye, there are about 100 melanophores in an area equal to the pupil in L. jocu vs. about 10 in L. apodus). Transitional recruits of L. apodus and L. griseus can sometimes overlap in appearance. If the bars are distinct from the base of the dorsal fin down to the anal fin, it is L. apodus; when L. griseus have bars, they are apparent on the upper body but fade towards the anal-fin base. As they grow, L. griseus develop distinct striping patterns on the lower body that do not occur on L. apodus.

Juvenile analogues:
The absence of a lateral spot separates L. apodus from most other juvenile snappers ((L. analis, L. mahogoni, L. synagris, and the deep-water snappers). Virtually all juvenile L. apodus have prominent vertical bars which are absent or indistinct in L. jocu, L. griseus, and L. cyanopterus. Rare individuals of L. apodus that have a uniform appearance or indistinct bars can be difficult to separate from juvenile L. jocu, but juvenile L. griseus of the same size would show some evidence of body stripes. Juvenile L. cyanopterus are narrower-bodied, have a wider caudal peduncle, and do not share the blue line under the eye.

Transitional stage:
Transitional recruits of L. jocu have a mostly-uniform scattering of fine melanophores on the body with notably indistinct bars against a finely-speckled background. The blue stripe from under the eye to the mid-maxilla is prominent.

Transitional analogues:
Transitional recruits of L. jocu develop indistinct bars in the same pattern as the prominent bars in L. apodus. The early recruits of the two species can be difficult to separate, but the bars on L. jocu are generally indistinct (particularly below the anterior dorsal-fin spines) and absent on the caudal peduncle. An additional difference is that the melanophores on L. jocu begin as a very fine and dense scattering vs. larger and sparser melanophores on transitional L. apodus (for example, in the space below the eye, there are about 100 melanophores in an area equal to the pupil in L. jocu vs. about 10 in L. apodus). L. jocu recruits can also be difficult to separate from transitional L. griseus, however the latter have large blotchy melanophores over a fine spotted background, vs. uniform fine speckling seen in L. jocu. L. griseus recruits also rapidly acquire their characteristic striping. L. cyanopterus early recruits share the indistinct bars but do not have the obvious blue stripe on the head and they retain their characteristic black edging to the pelvic fins through the transitional phase.

Juveniles:
Juvenile L. jocu have few distinct markings other than the thin blue line extending from the maxilla back under the eye and across the operculum. Most juveniles retain some evidence of indistinct bars.

Juvenile analogues:
Juvenile L. jocu have no lateral spot (vs. L. analis, L. mahogoni, L. synagris, and the deep-water snappers) and indistinct vertical bars (vs. prominent in L. apodus). They are wider-bodied than L. cyanopterus (which lacks the blue line under the eye as well). Juvenile L. griseus intensify the dark stripe through the eye and develop thin dark stripes on the side of the body.

An earlier version of the following description and some of the photographs have previously been published in Zootaxa (copyright reserved by Magnolia Press):

Victor, B.C., Hanner, R., Shivji, M., Hyde, J. & Caldow, C. (2009) Identification of the larval and juvenile stages of the Cubera Snapper, Lutjanus cyanopterus, using DNA barcoding. Zootaxa, 2215, 24-36.

Pretransitional mostly-unmarked stage, usually from 15-18 mm SL:
Body: A thin line of melanophores develops on each side just below the base of the spinous dorsal fin, from the third to sixth and then from the eighth to tenth spines (leaving an unpigmented dorsal midline along the base of the fin). Continuing along the base of the soft dorsal fin, the melanophore row widens to cover the outer pterygiophore segments, intensifying beneath the fourth to eighth and the last two rays and then extending along the dorsal midline of the caudal peduncle, ending at the start of the procurrent caudal-fin rays. Early transitional larvae begin to develop short melanophore streaks lining some of the myomere edges along the mid-upper body. A central patch of surface melanophores develops on the end of the caudal peduncle, then filling in progressively from ventral to dorsal. There are a few deep melanophores at the end of the lateral midline of the caudal peduncle. Along the ventral midline of the caudal peduncle there is a line of melanophores starting just after the melanophore underlying the base of the last anal-fin rays and extending up to the procurrent caudal-fin rays.
Head: Melanophores on the head consist of a dense patch overlying the brain and on the surface braincase with a scattering developing between the braincase and the first dorsal-fin spine. A patch of small melanophores develops at the tip of the upper jaw and then extends upward along the snout. The lower jaw is mostly unmarked, with only a few small melanophores near the tip. The opercular area is covered in iridescence extending down to the pelvic-fin insertion. The inner cleithral surface of the gill cavity is speckled with large melanophores and there are internal melanophores lining the dorsal aspect of the peritoneum extending down to the vent and overlain by a silvery camouflage layer.
Fin Spines: The dorsal and anal-fin spines are relatively slender, without prominent internal reticulations or serrations. The second dorsal-fin spine is the longest, with the spines becoming progressively and evenly shorter such that the profile of the spinous tips forms a straight downward-sloping line.
Fins: Melanophores on the dorsal-fin membranes are present along the full length of the membrane just behind the second dorsal-fin spine and then densely on the outer third of all of the subsequent spinous-dorsal-fin membranes. The soft dorsal fin is unmarked. There are a few melanophores between the bases of the lower central caudal-fin segmented rays. The anal fin is unmarked. The pelvic fins have dense melanophores along the outer third of the fin membranes of the longest two or three rays.

Pretransitional analogues:
Pretransitional larvae (mostly-unmarked, usually from 15-18 mm SL) have relatively slender and smooth dorsal and anal-fin spines, without the prominent internal reticulations and anterior serrations found in L. griseus, L. apodus, and L. jocu. In addition, amongst the regional Lutjanus only L. cyanopterus and L. analis have a mostly unmarked anal fin, with no melanophores on the membranes or even at teh base of most of the anal-fin elements before transition. Pretransitional L. cyanopterus share the relatively slender and smooth dorsal-fin spines and snout melanophores with L. analis, but have a distinctly-wider caudal peduncle and melanophores on the outer third of the longest pelvic-fin membranes (vs. full-length or none). On larval L. cyanopterus the dorsal-fin spines (after the first) are evenly and progressively shorter, unlike some other species. The anterior snout and upper jaw are speckled with melanophores with only a few on the lower jaw (vs. roughly similar on the upper and lower jaw and/or not on the snout as well in other species). L. cyanopterus larvae have a wider caudal peduncle than other regional Lutjanus species (body depth after last dorsal ray goes fewer than 2.5 times into body depth at first dorsal-fin spine).

Juveniles:
Juvenile L. cyanopterus have few distinguishing markings, primarily indistinct vertical bars and a dark outer portion of the spinous dorsal fin with abruptly-light edging. The black markings on the outer third of the pelvic-fin membranes shown by larvae can also persist well into the juvenile stage. Dark variants develop a black cap across the eyeball, uniformly-darkened pelvic-fin membranes, and intensified dark bars on the body and black edging to the spinous dorsal fin. Even in the juvenile stage, Cubera snappers have markedly-enlarged canine teeth. The body shape of juveniles and adults differs from other regional snappers in being longer and narrower; the body depth (predorsal) of L. cyanopterus juveniles goes at least 2.8 times into SL (vs. 2.4 or fewer).

Juvenile analogues:
Juvenile L. cyanopterus have no lateral spot (vs. L. analis, L. mahogoni, L. synagris, and the deep-water snappers) and lack the prominent eye stripes or blue lines across the cheek characteristic of L. apodus, L. jocu and L. griseus. In addition, the other regional Lutjanus have distinctly wider bodies as both juveniles and adults: the predorsal body depth of L. cyanopterus juveniles goes at least 2.8 times into SL (vs. 2.4 or fewer).