Description
Dorsal spines (total): 5-7 (usually: 6) ; Dorsal soft rays (total): 8-10 (usually: 9); Anal spines: 1; Anal soft rays: 7-9 (usually: 8); Pectoral rays: 19-18 (usually: 17); Branched caudal rays: 10-13 (usually: 12); Vertebrae: 10 + 16 = 26. A species of Trimma with predorsal partly scaled, midline naked or partly naked, cycloid scales at sides of nape reaching to above a point between posterior margin of operculum and eyes; Cheek and operculum naked; Pectoral base usually fully scaled, posterodorsal 2 scales slightly enlarged; Prepelvic covered with small cycloid scales in 5–6 rows; Interorbital narrow, with moderate groove; No groove or very shallow groove behind eyes (shallow between eyes and absent behind eyes in juveniles); Low distinct ridge at posterior end of interorbital; Gill opening extending forward to below posterior margin of pupil; Nape crest low from first dorsal origin to above posterior opercular margin, extending into shallow median groove; Groove extending to just behind eyes; Pectoral rays unbranched or with 1-5 rays branched at extreme tips; Fifth pelvic ray unbranched, rest of rays with 2 terminal tips; Pelvic fins largely separate, connected only at base; Fins widely separate, distance between two fins greater than base of single pelvic fin; Pelvic scale covering membrane; Fifth ray about one-fourth to one-half length of fourth ray. Head slightly compressed, eyes dorsolateral, head depth slightly greater than width at preopercular margin. Anterior nostril at end of tube just above upper lip; Posterior nostril with raised rim, 1 nostril diameter from anterior and 2-3 nostril diameters from eye. Nasal sac elevated. Postorbital length about equal to distance from tip of snout to posterior end of eye. Snout short, rounded in dorsal view, slightly convex in side view. Anterior margin of jaws in line with middle of eye in adult; Posterior end of jaws under or just behind anterior margin of eye in adult, behind anterior margin by up to one-fifth pupil diameter of eye in juveniles (< 15 mm SL). Suborbital region between eye and upper lip narrow, about one-third pupil diameter in juveniles to almost half pupil diameter in adults. Cheek slightly bulbous. Mouth very oblique, jaws forming an angle of 45-50° with body axis. Gill rakers on outer face of first arch slender, longer than gill filaments; Rakers on inner face of first arch and rakers on other arches denticulate at distal tip. Cephalic sensory papillae a reduced transverse pattern as in Figure 5b, rows b and d (of Sanzo 1911) moderately developed and consisting of 5-6 small papillae each. Tongue tip truncate to slightly emarginate. Teeth conical and slightly curved. Teeth in outer row of upper jaw wide-set and enlarged; 1-3 inner rows of small teeth tapering laterally to 1 row; Innermost row teeth slightly larger than teeth in middle rows. Teeth in outer row of lower jaw wide-set, enlarged, reaching to anterior half of jaw, with single tooth at angle of dentary on each side largest; 1-3 inner rows of small teeth; Innermost row slightly enlarged; Teeth just behind angle of jaw slightly larger than other teeth in row. Second and third spines of first dorsal fin subequal, none filamentous. First segmented ray of second dorsal fin usually unbranched, other rays branched. First segmented ray of anal fin usually unbranched, other rays branched, anterior branch of last ray branched once and posterior branch not subsequently branched. Caudal fin with rounded to truncate margin (upper rays often longer than ventral rays). Operculum and cheek without scales, midline of nape usually naked, but sometimes with 1-5 rows across midline anteriorly, sides of nape scaled to point above posterior end of operculum to posterior end of eye; Pectoral base covered with 6-9 cycloid scales in 2 vertical and 4 horizontal rows, posterodorsal 2 scales slightly enlarged, scales often missing in preserved specimens; Prepelvic area largely scaled in 5-6 rows of cycloid scales. First haemal arch not expanded, abdominal/caudal vertebral transition of Type B. Max. length: 2.7 cm SL. Depth range: 1 - 55 m.

Color
Head and body an overall blue or bluish-gray; Cheek with yellow or yellowishorange vertical bar at posterior end of preoperculum; Oblique yellow to reddish orange stripe above upper lip; Yellow to reddish-orange vertically elongate bar (width slightly less than pupil diameter) immediately behind eye; Narrow yellow or yellowish-orange vertical bar at upper posterior end of operculum; Body with 6 yellow to reddish orange irregularly shaped spots along back from just before first dorsal fin to end of second dorsal fin; Midside of body with 6 yellow to reddish-orange irregularly shaped bands below interspaces of upper spots; Series of small vertically elongate yellow to reddish-orange irregularly shaped spots on belly and above anal fin; Rarely with midside bands connecting to lower spots; Blue to bluish-gray interspaces between dorsal spots and midside spots forming zigzag pattern; Caudal peduncle with 3 oblique yellow to reddish-orange bands, sometimes X-shaped; Dorsal fins with thin (less than half pupil diameter) yellow stripe just above base and fainter yellow stripe just below distal tip of fins; Anal fin with yellow to red pigment on basal twothirds to three-quarters of fin; Caudal fin with yellow to red pigment covering all of fin except distal margins; Pelvic and pectoral fins white to translucent.

Etymology
Trimma: from Greek, trimma, -atos = something crushed.
maiandros: for Maiandros, the god of the winding Maeander River in Phrygia (currently known as the Büyük Menderes River in Turkey), son of Oceanus and his sister Tethys. The English word 'meander', a winding, crooked, or involved course, is in allusion to the zigzag pattern of grey to blue lines on the body.
Original description: Trimma maiandros Hoese, Winterbottom & Reader, 2011 - Type locality: Yonge Reef, 14°37'S, 145°38'E, Queensland, Australia, depth 1-15 meters, AMS party, 1 Dec. 1978.

Distribution
Cocos (Keeling) Islands (eastern Indian Ocean) to Japan, Marshall and Mariana Islands to Samoa and northern Australia, Solomon Islands and New Caledonia.

Biology
Occurs in mid to outer barrier reefs, but much more common on outer barrier islands. Also found in caves and crevices.