Key to species of Gordonoryssomus Almeida & Lima
1. Pronotum and elytra of a single color, without spots.......................................................... 2
1’. Pattern not as described above........................................................................... 3
2. Elytra black (Bolivia)............................................................ G. nigrus Almeida & Lima
2’. Pronotum and elytra reddish yellow (Peru and Bolivia).......................................... G. mirnae s p. nov.
3. Pronotum and elytra reddish brown; elytra with basal spot shaped by black pubescence (Brazil: ES)............................................................................................... G. nigripilosus Almeida & Lima
3’. Pattern not as described above........................................................................... 4
4. Elytra with one spot along the sutural margin............................................................... 5
4’. Elytra without spot along the sutural margin................................................................ 6
5. Elytra with one large yellowish red spot along the sutural margin, reaching almost 2/3 of the suture (Brazil: PI)................................................................................................. G. limeirai sp. nov.
5’. Elytra with one small orange spot on the center of elytral suture (Brazil: MG, RJ, SC, RS)..... G. delicatus Almeida & Lima
6. Male with length 3.44 and width 2.26 mm (Brazil: RJ)....................................... G. everardoi sp. nov.
6’. Male with length 4.08–5.00 and width 3.33–4.00 mm (Brazil: RJ, MG, SC and Chile)............... G. deyrollii (Crotch)