Tetragonotum megacephalum Ruckes, 1965

(Fig. 3B)

Distribution. Brazil: BA (Ruckes 1965), PE (new record).

Examined material. 26.IX.2017 (2 immature), 28.IX.2017 (4 immature), 30.X.2017 (1 immature), 21.IV.2018 (2 immature), 24.IV.2018 (1 immature), 09.VI.2018 (5 immature, 1 ♂), 13.VII.2018 (1 immature), 09.VIII.2018 (2 immature), 10.VIII.2018 (3 immature).

Comments. Tetragonotum megacephalum is known only by the holotype, a female collected in Iguassu, Bahia, Brazil (Ruckes 1965). We believe this locality is now on the premises of Itaeté, Bahia, also in the Caatinga biome. We have collected 21 immature specimens during both the dry and rainy season and a single male specimen in the rainy season in the Catimbau National Park. The identification of the immature specimens was unequivocal, because of the resemblance between immature and adult morphology. We include the immature of this species due to the species rarity in entomological collections and studies. Rolston (1990) includes T. megacephalum in the Discocephalini within a group of genera that have the interocular width equal to or greater than the length of the head and provides a dichotomous key to identify such genera.