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.
Based on the new information added here, a total of eight Lutjanus species are now recorded from the southwestern Atlantic (Brazilian common names are in parentheses): L. alexandrei , the Brazilian snapper (“ baúna ”, “caranha”, “caranho”); L. analis (Cuvier) , the mutton snapper (“caranho-vermelho”, “cioba”, “saioba”); L. bucanella (Cuvier) , the blackfin snapper (“pargo-boca-preta”); L. cyanopterus (Cuvier) , the cubera snapper (“caranha”, “caranho”); L. jocu (Bloch & Schneider) , the dog snapper (“ dentão ”, “vermelho”); L. purpureus (Poey) , the southern red snapper (“pargo”, “vermelho”, “cachucho”); L. synagris (Linnaeus) , the lane snapper (“ greacó ”, “ ariocó ”, “vermelho-henrique”, “ baúna ”); and L. vivanus (Cuvier) , the silk snapper (“pargo”, “vermelho”). Brazilian records of L. mahogany (Cuvier) , the mahogany snapper are probably based on misidentifications (Carvalho-Filho 1994). As noted for the western North Atlantic (e.g. Camber 1955, Carpenter1965), common names used for snappers has been very inconsistent in the southwestern Atlantic.
Key to the Western Atlantic species of Lutjanus (modified from Allen 1985 and Anderson 2003)
1a. Dorsal fin with 10 spines and usually 12 soft rays (rarely 11 or 13)............................................................2
1b. Dorsal fin usually with 10 spines (rarely 9 or 11) and 14 soft rays (rarely 13 or 15)................................. 3
2a. Gill rakers 7-8 + 15-17 (including rudiments); 1/4 to 1/2 of black lateral spot extending below lateral line; no evident paler (yellow in life) stripes on body and head; angle of preopercle greatly projecting and strongly serrated........................................................................................................... L. mahogoni (Cuvier) [southeastern coast of Florida and eastern coast of Yucatan peninsula to Venezuela]
2b. Gill rakers 6-7 + 13-14 (including rudiments); less than 1/4 of black lateral spot extending below lateral line; 8-10 prominent paler (golden-yellow in life) stripes on body, often also 3-4 irregular paler (goldenyellow in life) stripes on head; angle of preopercle scarcely projecting and finely serrated......................... ................................................................................................................................... L. synagris (Linnaeus) [Bermuda and North Carolina to Santa Catarina, southern Brazil, including the West Indies, Gulf of Mexico, and Caribbean Sea]
3a. Large, pronounced black spot at base and in axil of pectoral fin in specimens larger than 5 cm SL; dark area at base of soft portion of dorsal fin (not always visible on preserved specimens); no black spot on flanks; anal fin rounded ............................................................................................ L. buccanella (Cuvier) [Bermuda and North Carolina to northeastern Brazil (at least to Bahia), including West Indies, Gulf of Mexico, and Caribbean Sea]
3b. No black spot at base or axil of pectoral fin no dark area at base of soft portion of dorsal fin; black spot on flanks may be present or absent; anal fin rounded or angulate .................................................................... 4
4a. Anal fin angulated, at least in specimens larger than 10 cm SL; middle anal-fin rays produced, the longest at least half length of head (rounded in L. analis , L. campechanus , L. purpureus and L. vivanus less than 4 to 6 cm SL); a black spot on flank (disappears in L. campechanus , L. purpureus and L. vivanus at about 20 cm SL) ......................................................................................................................................................... 5
4b. Anal fin rounded at all sizes, middle rays less than half the length of head; no dark spot on flank ............ 8
5a. Vomerine tooth path without a distinct medial posterior extension; anal soft rays usually 8 (rarely 7); iris red in life; spot on flanks below anterior part of soft dorsal fin distinct at all sizes, being relatively larger in smaller specimens .......................................................................................................... L. analis (Cuvier) [New England to São Paulo, southeastern Brazil, including West Indies, Gulf of Mexico, and Caribbean Sea]
5b. Vomerine tooth path triangular or anchor-shaped, with a medial posterior extension; anal soft rays 7 to 9; spot on flank below anterior part of soft dorsal fin distinct in smaller specimens but may be absent in specimens larger than 20 cm SL ( L. campechanus , L. purpureus and L. vivanus ) ............................................. 6
6a. Scales on sides of anterior part of body, below lateral line, conspicuously larger than those on posterior part of body; anal soft rays 9 (rarely 8); lateral line scales usually 47 or 49 (rarely 46 or 50); scales above lateral line 7 to 10, most frequently 8 or 9 ............................................................... L. campechanus (Poey) [North American coast from Massachussetts to the Florida Keys and in the Gulf of Mexico; rare north of the Carolinas]
6b. Scales on anterior part of body, below lateral line, not conspicuously larger than those on posterior part of body; anal soft rays 8 (rarely 7 or 9); lateral line scales usually 50 or 51 (rarely 49, 52 or 53); scales above lateral line 9 to 12, most frequently 10 or 11 ............................................................................................... 7
7a. Cheek scale rows 6 (rarely 5 or 7); scales above lateral line, on anterior part of body, smaller than those below; scales below lateral line 16 to 19; lateral spot on flank present on juveniles equal to, or larger than eye; iris red in live and freshly preserved specimens; sum of lateral scales and scales above and below lateral line usually 77 to 81 (rarely 76 or 82) .................................................................... L. purpureus (Poey) [Yucatan Peninsula and the southern coast of Cuba southeastward throughout the Caribbean and most of the Antilles to São Paulo, southeastern Brazil; also collected at localities off the Carolinas, Georgia, and Northeast Florida].
7b. Cheek scale rows 7 (rarely 8); scales on anterior part of body above lateral line, on anterior part of body, about equal in size to those below; scales below lateral line 20 to 24; lateral spot on flank, when present, smaller than eye; iris yellow in live and freshly preserved specimens; sum of lateral scales and scales above and below lateral line usually 82 to 87 (rarely 81 or 88) ..................................... L. vivanus (Cuvier) [Bermuda and North Carolina south to São Paulo, southeastern Brazil, including West Indies, Gulf of Mexico, and Caribbean Sea]
8a. Vomerine tooth patch without a distinct medial posterior extension; upper and lower canines very strong and about equally developed; cheek scales usually in 9 rows (rarely 8 or 10) ........ L. cyanopterus (Cuvier) [Nova Scotia and Bermuda south to São Paulo, southeastern Brazil, including West Indies, Gulf of Mexico, and Caribbean Sea]
8b. Vomerine tooth patch triangular or anchor-shaped, with a distinct medial posterior extension; upper canines larger than lower; cheek scales usually in 7 or 8 rows (rarely 5, 6 or 9) ........................................ 9
9a. Usually 9 to 10 scales between dorsal-fin origin and lateral line (rarely 8 or 11); 45-49 transverse scale rows on body; a triangle-shaped whitish bar between the ventral margin of the orbit and the area immediately posterior to the maxilla in specimens larger than 15 cm SL.................... L. jocu (Bloch & Schneider) [From Massachussets south to São Paulo, southeastern Brazil, including West Indies, Gulf of Mexico, and Caribbean Sea; rare north of Florida]
9b. Five to 7 scales between dorsal-fin origin and lateral line; usually 40 to 43 (rarely 39 or 44) transverse scale rows on body; no triangular whitish bar between the ventral margin of the orbit and the area immediately posterior to the maxillary...............................................................................................................10
10a. Scale rows below soft portion of dorsal fin oblique to the longitudinal body axis; no evident banding pattern on body..................................................................................................................... L. griseus (Cuvier) [Massachussets and Bermuda to French Guiana, including West Indies, Gulf of Mexico, and Caribbean Sea]
10b. Scale rows parallel to the longitudinal body axis, not becoming oblique below the posterior portion of soft dorsal fin; evident banding pattern on body (may disappear in preserved specimens)......................11
11a. Yellowish to gray fins and body; eight pale vertical lines usually present separating darker bands on dorsal surface of flank; sixth pale vertical line under the junction of spiny and soft portions of dorsal fin; no conspicuous dark spots on cheek and preopercle ...................................................... L. apodus (Walbaum) [Massachusetts and Bermuda south to Tobago, including West Indies, Gulf of Mexico, and Caribbean Sea]
11b. Reddish fins and body; six white vertical lines separating darker bands on dorsal surface of flanks; fifth paler vertical bar under junction of spiny and soft portions of dorsal fin; conspicuous dark spots (bright blue in life) on cheek and preopercle, 7-10 of these typically present with varying placement on snout and ventral portion of head ................................................................................................... L. alexandrein. sp. [Tropical southwestern Atlantic, from Maranhão to Bahia, Brazil]
Lutjanus is a genus of marine ray-finned fish, snappers belonging to the family Lutjanidae. They are found in the Atlantic, Indian, and Pacific Oceans. They are predatory fish usually found in tropical and subtropical reefs, and mangrove forests. This genus also includes two species that only occur in fresh and brackish waters.
Lutjanus was created in 1790 by the German physician and zoologist Marcus Elieser Bloch with Lutjanus lutjanus as its type species by tautonymy.[1] It is the type genus of the subfamily Lutjaninae and the family Lutjanidae. The name is derived from a local Indonesian name for snappers, ikhan Lutjang.[2] Bloch erroneously stated that the type locality for L. lutjanus was Japan when the name he gave it suggested that it was collected in the East Indies.[3] A taxonomic study of snappers within the subfamily Lutjaninae in the tropical western Atlantic Ocean indicated that the at monotypic genera Ocyurus and Rhomboplites sit within the genus Lutjanus.[4] Lutjanus ambiguus is considered by some authorities to most likely to be a hybrid between L. synagris and Ocyurus chrysurus, supporting the close relation between the two genera.[5]
Currently, 73 recognized species are placed in this genus:[6][7]
Lutjanus snappers are small to large in size with oblong shaped bodies which vary from deep to slender and fusiform in form. They have relatively large mouths which is protractable. The teeth are arranged in one or more rows in the jaws and are pointed and conical in shape with the outer row consisting of canine-like teeth with the anterior ones enlarged into more obvious canine-like fangs. The vomerine teeth are arranged in patches which may be chevron, triangular or lunate and may or may not have a posterior extension, or be arranged in a rhombus. The space between the eyes is convex and they have a aserrated preopercle which has a deep incision on its lower margin. They sometimes have a bony knob between the operculum and the preopercle which is most obvious in those species which have a deep incision in the preopercle. They have a continuous dorsal fin, frequently having a slight incision between the spiny portion and the soft-rayed portion. The spiny part of the dorsal fin may have 10 or 11 spines while the soft rayed part may have 11 to 16 rays. The anal fin has 3 spines and between 7 and 10 soft rays while the pectoral fins have between 15 and 18 soft rays. The dorsal and anal fins are scaled while the caudal fin may be emarginate, truncate or, rarely, forked. These snappers are extremely variable in colour frequently having a background colour of reddish, yellow, grey, or brown overlain with a pattern of darker stripes or bars. They are often marked with a large blackish spot on upper flanks underneath the front soft rays of the dorsal fin.[12]
Lutjanus snappers have a circumtropical and subtropical distribution and are found in the Atlantic, Indian and Pacific Oceans.[12] The mangrove red snapper (Lutjanus argentimaculatus),[13] and the dory snapper (Lutjanus fulviflamma) have been recorded in the Mediterranean as possible Lessepsian migrants having entered that sea through the Suez Canal from the Red Sea while the dog snapper (Lutjanus jocu), a western Atlantic species, has been recorded in the Ligurian Sea.[14] Many species are associated with coral reefs where they are conspicuous members of the fish fauna, while some of the larger red snapper species descend into deeper waters, at least to 200 m (660 ft) in depth.[12] 2 species, L. fuscescens and L. maxweberi, only occur in fresh and brackish waters.[7]
Smaller Lutjanus species are often observed in large, diurnal aggregations which stay near the reef, these disperse at night to feed. Their diet is largely made up of fishes and crustaceans. Group spawning has been obserbed in at least one species. Courtship is initiated by the males who peck and rub themselves on the females' body and when other individuals are attracted to the initial pair they all spiral towards the surface, releasing the milt and eggs just underneath the surface. The eggs are minute and spherical in shape and take 18 hours or so to hatch into larvae.[12]
Lutjanus is a genus which contains many species, especially the larger ones, which are important commercial fish and which are considered to be excellent food fish in the tropics. The catch is taken using a variety of methods including handlines, traps, spears, nets and trawling gear. They are mainly sold as fresh fish but may be preserved by freezing or dry-salted.[12]
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{{cite journal}}: CS1 maint: uses authors parameter (link) {{cite journal}}: CS1 maint: uses authors parameter (link) Lutjanus is a genus of marine ray-finned fish, snappers belonging to the family Lutjanidae. They are found in the Atlantic, Indian, and Pacific Oceans. They are predatory fish usually found in tropical and subtropical reefs, and mangrove forests. This genus also includes two species that only occur in fresh and brackish waters.
