Dorsal spines (total): 10; Dorsal soft rays (total): 14 - 16; Analspines: 3; Analsoft rays: 11 - 12
9.8 cm SL (male/unsexed; (Ref. 74965))
This species is distinguished by the following set of characters: 2 post-maxillary processes; D X,14-15 (usually 15); A III, 11-12 (usually 12); pectoral rays 20-21(usually 20); lateral-line scales 72-80 (modally 74); scales above lateral line to origin of dorsal fin 6-7 (usually 7); scales below lateral line to origin of anal fin 12-14 (usually 13); circumpeduncular scales, anterior modally 12.14, ventral modally 14.71; body is fusiform in shape and extremely elongate for the genus, greatest depth 4.3-5.1 in SL; HL 3.2-3.6 in SL; snout 4.0-5.2 in HL; eye 2.9-3.6 in HL; pectoral-fin length 1.2-1.4 in HL; in life, color blue, grading to silvery white on belly, with prominent, broad yellow stripe on upper side from dorsal posterior margin of operculum to upper half of caudal peduncle, covering maximum of four scale rows, centered just above lateral line, except entirely above it on caudal peduncle; tip of each caudal-fin lobe with reddish spot (often appearing black underwater), before this is a whitish area (Ref. 74965).
Paratype for Pterocaesio monikae Allen & Erdmann
Catalog Number: USNM 390775
Collection: Smithsonian Institution, National Museum of Natural History, Department of Vertebrate Zoology, Division of Fishes
Collector(s): M. Erdmann
Year Collected: 2006
Locality: Indonesia: Papua Province, Cenderawasih Bay, Tridacna Atoll, Papua Province, Indonesia, Pacific
Paratype: Allen, G. R. & Erdmann, M. V. 23 Jan 2008. Aqua: Journal of Ichthyology and Aquatic Biology. 13 (3-4): 165, Figs. 2, 3, 5.