Holotype male: “BRAZIL: Mato Grosso do Sul, cerradão fragment nr. Selviria at 20°20'10"S, 51°24'36"W, Window trap, ground level, trail 1, 17.xii.2010, C.A.H. Flechtmann” / “Caterino/Tishechkin Exosternini Voucher EXO-00644” / “HOLOTYPE Mecistostethus flechtmanni Caterino, Tishechkin & Dégallier”, in MEFEIS. Paratypes (3 males): same locality as type, collected 14.i.2011 and 28.i.2011 by CAH Flechtmann, and 31.xi-3.xii.2011 by MSC and AKT (DNA Voucher EXO-00933, extract MSC-2274), in MEFEIS, FMNH.

Length 1.8-2.0mm, width 1.4-1.6mm; frontal stria complete but weak at middle (Fig. 2B); frons and epistoma with microsculpture; anterior submarginal pronotal stria long, recurved posterad at apices (Fig. 3F); lateral pronotal punctures present; pronotum with <10 discal setae present on disk in addition to submarginal row (Fig. 3F); prosternal striae absent (Fig. 4D); metaventral stria interrupted at middle (Fig. 4D); microsculpture at apex of elytra conspicuous; elytral stria 1 complete, with few setae, mainly near apex; elytral stria 1 and 2 reaching elytral base; tegmen (Figs 6I–J) narrow, weakly tapered in basal half, constant in width in most of apical half, with shallow but strongly delimited basoventral concavity in just less than basal one-half; with very weak ventral swelling near midpoint; median lobe short, about one-fourth tegmen length.

This species is known only from the type locality, collected in a fragment of «cerradão» forest close to the Paraná River in extreme eastern Mato Grosso do Sul. This forest is a relatively moist, taller and denser form of the cerrado subtropical biome.

This species is named for the collector of most of the type series, and our gracious host during a productive visit to the site, Dr. Carlos Flechtmann of Universidade Estadual Paulista (Department of Plant Protection, FEIS/UNESP, Ilha Solteira campus).