Heteragrion thais Machado, 2015

(Figs. 63a–d)

[Key locator: Key to Group A species, couplet 31 (30)] Heteragrion thais: Machado 2015: 391–396 (description and diagnosis of ♁; comparison with H. beschkii and H. luizfelipei; figs. 1–5);— Lencioni 2017: 157–158 (general taxonomic information; distribution; fig. 81).

Material examined. 1♁ (HOLOTYPE) BRAZIL, Minas Gerais state, Municipality of Barroso, Mata do Baú (Baú Forest), 28.i.2011, (-21.1869, -43.9761, centroid, 1100m asl), M.M. de Souza leg., ABMM (head missing); 2♁♁ (PARATYPES) same data, but 20.xi.2010, and 05.ii.2011.

Known distribution. Brazil (Southern Minas Gerais state).

Diagnosis and remarks. This rare species is assessed as Data Deficient in the IUCN Red List, as despite being recently collected in 2011, little is known about its distribution and preferred habitats, pending further collections to determine its actual conservation state (Vilela & Guillermo-Ferreira 2021k). The following character combination distinguishes this species from the remainder of Group A species: posterior margin of upper plate straight (Fig. 63c), upper plate concave at its middle (Fig. 63d); ML apex squared (Figs. 63c–d).