Key to the species of subgenus Tragardhus
1. Third elytral interval forming a sharp and strongly raised continuous costa (Fig. 4F)............................... 2
-. Third elytral interval composed of more or less elongated tubercles (Fig. 4G)..................................... 3
2. Anterior pronotal angles protruding outwards. Lateral sides of pronotum, at base, straight. Eighth elytral interval composed of short tubercles (Fig. 4D)............................................................... T. (T.) majae sp. nov.
-. Anterior pronotal angles not protruding outwards. Lateral sides of pronotum rounded. Eighth elytral interval, at least at middle, with a sharply raised continuous costa (Fig. 4C).............................................. T. (T.) jani sp. nov.
3. Fifth, seventh and ninth elytral intervals with a sharply raised continuous costae (Fig. 2H). Male protibia with a prominent, obtusely dentiform, arcuate median dilatation (Fig. 2J)....................................... T. (T.) glandipleurum
-. Fifth, seventh and ninth elytral intervals composed of more or less elongated tubercles (Fig. 2I). Male protibia without median dilatation........................................................................................... 4
4. Pronotum cordiform, sinuate anterior to basal angles (Fig. 4E). Third, fifth and seventh elytral intervals covered with coarse, dense tubercles; second and fourth intervals covered with sparse tubercles........................... T. (T.) stigmaticus
-. Pronotum narrowed, subparallel in basal half (Fig. 4A). Third, fifth and seventh elytral intervals covered with sparse tubercles; second and fourth intervals not covered with tubercles........................................... T. (T.) biapicalis