Description
Dorsal spines (total): 7; Dorsal soft rays (total): 9-10; Anal soft rays: 8-9; Pectoral fin rays: 17-18; Pelvic fin rays: I, 4, with the fifth rays absent or rudmentary. The gill menbranes extend far forward and are narrowly attached to the isthmus; The caudal fin is rounded; There are two pairs of canines on each side of each jaw, with a band of villiform teeth inside the outer row of canines; The body is compressed, the head not depressed; The mouth is oblique, the lower jaw a little longer; The maxillaries reach to under front of pupil; The interorbital is very narrow, bony, and concave; Anal fin origin under that of the second dorsal origin; Anus immediately in front of anal fin; Pelvic fins not fringed, and reaching to anus or to origin of anal fin; Pectorals extending to anal origin; No elongate rays in median fins; No dermal flaps on shoulder girdle; No teeth on vomer or palatines; Anterior nostril tubular, posterior nostril not tubular, no pores in midline of interorbital space; Head naked, no scales in front of dorsal fin, no scales on breasts. Max. length: 2.1 cm SL. Depth range: 0 - 10 m.

Color
Red, with eight blue vertical bars dorsally, the first under middle of eye, very short; The second a saddle from top of head past rear margin of eyes ending at lower margin of cheeks; The third a short saddle midway from eyes to origin of first dorsal ending at upper edge of opercle; Fourth at origin of spiny dorsal across pectoral base ending at base of lowest ray; Fifth under middle of spiny dorsal; Sixth at origin of second dorsal ending at origin of anal; Seventh near rear of base of soft dorsal, and eighth a round blotch posteriorly on dorsal part of caudal peduncle.

Eviota corneliae (Fricke, 1998) - reported from Maré Island, Loyalty Islands, New Caledonia - Is a synonym of Trimmatom eviotops (Schultz, 1943). Color in life: head and body brigh yellow. Head with 3 narrow vertical blackish brown bars, one across the eye, one right behind the eye, and one above the preopercle. Sides of body with 5 thin vertical dark brown trunk bars, the last trunk bar developed as a saddle on the caudal peduncle, the other bars reaching three-fourths across the sides of the body, trunk bars discrete, uniform.

Etymology
Trimmatom: from Greek, trimma, -atos = something crushed + from Latin, atomus = an atom, particle incapable of being divided. Referring to small size of Trimmatom nanus (Winterbottom & Emery, 1981) and Trimmatom offucius (Winterbottom & Emery, 1981).
eviotops: from Greek prefix, ev-, eu-, = good or well, very + from Greek letter, iota = smallest letter in the Greek alphabet and often figuratively used to describe anything small or insignificant + from Ancient Greek suffix, -óps = eye, face, appearance. Referring to Eviota epiphanes (Jenkins, 1903), which, at 1.0-1.9 cm in length, Jenkins claimed was the “smallest vertebrate that has up to this time been described”.
Original description: Trimma eviotops Schultz, 1943 - Type locality: reef of Rose Island, American Samoa, collected by Leonard P. Schultz, June 11-14, 1939 along with five paratypes.

Distribution
Indo-West Pacific: Chagos Islands, Australia, New Caledonia, Fiji, Samoa, Society Islands, Rapa, Tuamoto Islands, and Ducie Islands (Pitcairn).

Biology
Inhabits lagoons and on the 'reef top'.

Similar species
Lythrypnus dalli (Gilbert, 1890) - Reported from Eastern Pacific: central California (U.S.A.) south to Peru, including Gulf of California (Mexico) and Galapagos Islands (Ecuador).

Lythrypnus gilberti (Heller & Snodgrass, 1903) - Reported from Eastern Pacific: Galápagos Islands.