A description of the early juvenile colour patterns of eleven Lethrinus species (Pisces: Lethrinidae) from the Great Barrier Reef, Australia Author Wilson, G. G. text Records of the Australian Museum 1998 1998-05-13 50 1 55 83 https://journals.australian.museum/wilson-1998-rec-aust-mus-501-5583/ journal article 10.3853/j.0067-1975.50.1998.1274 96fd1ba3-d7b3-402d-a5a4-7e4df747ed2e 0067-1975 4652850 Lethrinus variegatus Valenciennes PI. 3D, Fig. 10 Material examined. ( 29 specimens : 14-114 mm ). AUSTRALIA Great Barrier Reef region , AMS 1.32476 - 004 (2: 16 mm ), AMS 1.34911 - 011 (1: 30 mm ), AMS 1.34911 - 012 (1: 25 mm ), AMS 1.34933 - 001 (2: 14 mm ), AMS 1.34934 - 001 (2: 28-47 mm ), AMS I.34935-001 (3: 34-35 mm ), AMS 1.34936 - 001 (1: 32 mm ), AMS 1.36201 - 001 (1: 15 mm ), AMS 1.37803 - 001 (1: 16 mm ), USNM 336691 (3: 26-35 mm ), not retained (9: 24-69 mm ) ; FIJI Suva , AMS 1.22232 - 016 (1: 114 mm ) ; INDONESIA EasternArchipelago , NMV 46329 (1: 73 mm ) ; PAPUA NEW GUINEA Trobriand Islands , AMS I.17102-015 (1: 38 mm ) . Diagnosis. Body slender, body depth 3.1-3.5 in SL; 4.5 dorsal scale rows, 13-14 ventral scale rows; maxillary serrations absent at greater than 23 mm ; cheek scales retained until 47-50 mm ; dorsal spine 4 the longest. Diagnostic colour notes. Dorsum finely-mottled grey-tan, seldom with dark banding, dorsal margin of lateral-line off-white; dark mid-lateral stripe semi-permanent, yellowish brown, width approximately 4.0 in body depth, shoulder blotch inconspicuous or absent; ventral half of body abruptly silvery off-white; dark suborbital blotch at greater than 30 mm ; fins hyaline. Pre-settlement colour notes. At 14-16.5 mm ( Fig. 10 ): head and body translucent off-white, melanophores overlying yellow-orange xanthophore pigmentation; distinct dark stripe extending from lips to orbit margin, continuing as dark mid-lateral stripe between posterior margin of orbit and caudal peduncle, may appear as series of irregular blotches; lateral-line cryptic, 3-5 irregular blotches along dorsum, interspaces silver, occasionally 3- 6 less-distinct blotches extending below dark mid-lateral stripe from pectoral fin to mid-way along caudal peduncle, further 2-3 irregular blotches adjacent to anal fin; fins hyaline. Colour notes. A distinctive species with minimal ontogenetic variation following settlement, few differences noted between field and captive or freshly-killed colouration. At 25-50 mm : dorsum and nape finely-mottled grey-tan, 4-6 narrow dark bands above lateral-line and 2- 3 similar bands along caudal peduncle, often switched off in field, lateral-line bordered dorsally by silvery off-white interspace in field; yellow-brown mid-lateral stripe extending from lips through orbit to base of upper caudal rays, semi-permanent (cf. intermittent stripe in other species), width 4.0 in body depth, may appear as series of dark blotches in captivity ( PI . 3D), blotch below dorsal spines 3-4 forming diffuse cuboidal shoulder blotch; ventral half of body and head abruptly silvery white, without dark markings in field, often 2-3 diffuse brown stripes or bands between pectoral and anal fins in captivity ( PI . 3D) or after death, 3-4 dark blotches on cheek and operculum from 25 mm ; fins mostly hyaline, anterior half of spinous fins with diffuse dark patches over off-white to pale yellow, caudal fin pale yellow with 2-3 indistinct dark bands at greater than 40 mm . Colour in alcohol. At 25-50 mm , dorsum and nape uniform pale tan; lips and snout with dense melanophores, dark dorsal bands retained though dulled, often connecting with broad blotches on flank, dark mid-lateral stripe identical hue to dorsum, shoulder blotch usually visible; body abruptly off-white ventrally, faintly mottled; fins hyaline, sparse melanophores retained along spines. Ecology. Moderately common in shallow seagrass beds on lagoonal or fringing coral reefs ( Cymodocea , Halodule , Thalassia ; 0.2-4 m ), absent from non-seagrass areas at Green Island at less than 100 mm ; solitary when recentlysettled ( 20-40 mm ), larger juveniles occasionally join small multi-species schools with congeners, particularly L. atkinsoni , L. genivittatus , L. harak , and L. obsoletus ; observed resting on the substrate among seagrass shoots at night, not fleeing when approached. Field identification. Distinguished from other Lethrinus species by its elongate body and snout profile, and prominentyellow-brownmid-lateralstripe. Whenobserved from behind, may be confused with species such as L. obsoletus or L. genivittatus on the basis of their similar dark mid-lateral stripes. When freshly collected, particularly at night, may appear a uniform pale olivaceus cream; the dark mid-lateral stripe and shoulder blotch becoming visible after 10-30 seconds. Previous descriptions. Colour plates of juveniles were included in Kuiter & Debelius (1994) and Kuiter (1996) (size not given in each case), and Lee (1993) (specimen 147 mm , misidentified as L. semicinctus ).