Polybia scrobalis Richards, 1970

(Figs 7, 15, 23, 31, 40, 52, 53, 54, 55)

Polybia scrobalis Richards, 1970: 302 . Holotype ♀, Brazil: MT (MNRJ; lost); one paratype with same data as the holotype (NHM) was examined by O. T. Silveira. Richards 1978: 40, 86; Silva & Silveira 2009: 320

This species was described by Richards (1970) based on a female holotype and seventy-nine female paratypes from Brazil (Mato Grosso), plus fifty females from several places in Brazil (AC, AM, PA, RO), and an additional female from Peru (Loreto). Unfortunately, the holotype and paratypes from Mato Grosso deposited in the Brazilian MNRJ were lost in the 2018 fire. Richards (1970) also recognized a subspecies, P. s. surinama, based on a female holotype and seventeen female paratypes from Suriname, plus two females from Brazil (AM). Later, Richards (1978) described an additional subspecies, P. s. pronotalis, based on females (holotype and five paratypes) from Colombia (Cali) and an additional female from Ecuador (Napo).

According to Richards (1978), the nominotypical subspecies has already been recorded from Brazil (AC, AM, MT, PA, RO), Peru (Cusco; Loreto) and Bolivia (La Paz). The subspecies P. s. pronotalis has been recorded from Colombia and Ecuador, and P. s. surinama from Brazil (AM, AP) French Guiana, Suriname, Panama, Costa Rica and Colombia. This latter form is a distinct species separable from the other subspecies by the pronotal carina demarcated at sides, gena slightly wider with stronger margin, and first metasomal tergum most often dark, unmarked; if it has a distal yellow band then this is never wide (see below).