Gonioterma pleonastes is a moth of the Depressariidae family. It is found in French Guiana. The wingspan is about 23 mm. The forewings are light greyish-ochreous with the costal edge ochreous-yellowish and with a small oblique dark fuscous mark on the base of the costa. The subcostal area is broadly suffused with ochreous-whitish on the anterior half, including a line blackish dash towards the base and a slender blackish streak along the fold from the base to the middle, terminated by the plical stigma. The first discal stigma is represented by an elongate blackish spot, the second by a blackish dot, the discal area around these irregularly marked with dark brown suffusion. The dorsum is broadly suffused with dark brown fromthe base to two-thirds and three dark brown costal spots, becoming