Branched nasal cirri. 2 pairs of short orbital cirri, posterior branched and anterior simple.
Males: brown with a darker head. Body plain with few patterns, but may have faint blue-grey lines on midflank. Front of dorsal fin a solid brown. Lower jaw with white spots. Females a dark, rich brown. Lower head a light brown. Head and lips with a red webbing which becomes larger and more obvious on the lower head and jaw. Row of white blotches just below midflank, first few upside-down U-shaped which reach lower body. Blotches become smaller and shorter posteriorly. Upper body with white marbling pattern. First 2/3 of dorsal spines with horizontal, slightly slanted, red alternating white stripes. This tapers off into a broad red stripe on the base for the rest of the 1/3 of the fin. Base of caudal fin white and caudal rays red fading to yellow.
Reaches 4.7 cm.
Found in holes in rocks.
Photos of this species can be found here.
Males of N. nudiceps have small spots along the body while those of N. monogrammus are patternless. Females of N. monogrammus are patternless with red and white wavy stripes on throat, while females of N. nudiceps are heavily patterned with white blotches on the body and a lower pale head with red webbing.