Naupactus delicatulus is characterized by a distinct color pattern of dense scales, light bluish-grey or light green, with whitish or cream longitudinal wide stripes along sides and margins of pronotum, extended on 2º to 3º elytral intervals and marginal intervals; the former stripe is partially interrupted on the anterior third, where there is a short band along the 4º interval.
Rostrum and antennae are very slender, pronotum is truncate-conical, impressed along midline, and sides; elytra are very elongate, slightly convex, with bisinuate base, well-developed humeri and distinct punctures on the striae; front tibiae do not have denticle on inner margin; and corbels of the hind tibiae are moderately broad, squamose.
Males are more slender than females.
Unknown.
Associated with vegetation of the Paranaense forest.