KEY TO GUATEMALAN SPECIES OF PHRYGIOPILUS SMALLEY, 1970 (ADAPTED FROM RODRÍGUEZ 2001)
1. G1 with mesial process present .................................................................................................................... 2
— G1 with mesial process absent (Fig. 4J) ....................................................... Ph. strengerae (Pretzmann, 1965)
2. G1 with mesial process conical, unilobed .................................................................................................... 3
— G1 with mesial process subtriangular, bilobed (Fig. 4F, H, I) .......................... Ph. ibarrai (Pretzmann, 1978)
3. G1 with lateral lobe absent .......................................................................................................................... 4
— G1 with lateral lobe present (Fig. 5F) ............................................................................... Ph. senticosus n. sp.
4 G1 with supra-apical process rounded (Fig. 4 A-C) ...................................... Ph. acanthophallus Smalley, 1970
— G1 with supra-apical process subtriangular (Fig. 4D, E) .................................. Ph. chuacusensis Smalley, 1970