Description: Body wide and relatively thick with a sloping forehead and a large round eye and large terminal mouth. Dorsal-fin base long and anal-fin base short. Prominent stout dorsal, anal, and pelvic-fin spines and a large non-serrated preopercular spine.
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. Diagnosis: Modal fin-ray counts of D-X,14 A-III,8 are shared among most of the regional Lutjanus, including L. analis, L. apodus, L. cyanopterus, L. griseus, L. jocu and the deep-water snappers L. buccanella, L. campechanus, and L. vivanus. Juvenile L. cyanopterus have an indistinct barred pattern without a lateral spot. Adult Cubera snappers are the largest Western Atlantic snappers and can reach four feet in length and weigh up to 125 pounds. (DNA)
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).
