Males: Protarsomeres dorsoventrally flattened, densely setose ventrally (Figs. 30-31, 33-34); terminal sternite with margin emarginated; abdominal sternites in lateral view appearing concave or flat. Females: Protarsomeres dorsoventrally flattened or not, with or without dense ventral setae; terminal sternite with margin entire or rounded, not emarginated; abdominal sternites in lateral view appearing convex.
1.
 Mentum with apicomedial, tooth-like projection (Fig. 16, 41)
3

Trizogeniates foveicollis
Figure 16
Figure 41
Figure 16. Geniatini and Anoplognathini with labrum and mentum (each) possessing median, apical tooth or projection. Figure 41. Trizogeniates foveicollis (clypeal apex with apicomedial tooth-like projection).

1'.

Mentum without apicomedial, tooth-like projection (Figs. 38-40)
2

Mimogeniates margaridae

Rhizogeniates antennatus

Rhizogeniates carbonarius
Figure 38
Figure 39
Figure 40
Figures 38-40. Clypeus of: 38)Mimogeniates margaridae (apex quadrate and crenulate, lacking apicomedial tooth), 39) Rhizogeniates antennatus (weakly emarginate apically, lacking apicomedial tooth), 40) Rhizogeniates carbonarius (weakly emarginate apically, lacking apicomedial tooth.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2(1).
. 		Apex of mentum with medial notch, not crenulate (Figs. 39-40). All claws simple on all legs
 

2'.
.

Apex of mentum crenulate (Fig. 38). Modified claw moderately split on all legs
Mimogeniates Martínez

Mimogeniates margaridae

Rhizogeniates antennatus

Rhizogeniates carbonarius
Figure 38
Figure 39
Figure 40
Figures 38-40. Clypeus of: 38)Mimogeniates margaridae (apex quadrate and crenulate, lacking apicomedial tooth), 39) Rhizogeniates antennatus (weakly emarginate apically, lacking apicomedial tooth), 40) Rhizogeniates carbonarius (weakly emarginate apically, lacking apicomedial tooth.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3(1).
. 		Mesosternum anterior to mesocoxae strongly concave (Fig. 52)
Xenogeniates
Villatoro & Jameson
 

3'.
.

Mesosternum anterior to mesocoxae flat or slightly convex, not strongly concave (Fig. 51)
.
4

Bolax magna

Xenogeniates martinezi
Figure 51
Figure 52
Figure 51-52. Thorax in ventral view showing: 51) Mesosternum without invagination (Bolax magna) and 52) Mesosternum with invagination in black (Xenogeniates martinezi).
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4(3).
. 		Stipes of maxilla produced, with well-developed lateral lobe (Fig. 43) or lateral angle (Fig. 42)
 

4'.
.

Stipes of maxilla not produced, instead rounded or broadly rounded (Fig. 44)
5
.
Lobogeniates borgmeieri
Lobogeniates catullus

Trizogeniates foveicollis
Figure 42
Figure 43
Figure 44
Figure 42-44. Maxilla (ventral view) showing: 42) Lobogeniates borgmeieri (stipes produced, with lateral angle), 43) Lobogeniates catullus (stipes produced, with well-developed lateral lobe), 44) Trizogeniates foveicollis (not produced, instead rounded or broadly rounded).
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5(4).
.
.
. 		Mandible with rounded, recurved, apical lobe (Fig. 20). Dorsal surface with abundant, decumbent, white setae. Antennal club of male twice length of segments 2-7; antennal club of female subequal to segments 2-7
Eunanus Ohaus
.
.
 

5'.
.
.
.

Mandible lacking rounded, recurved, apical tooth; instead simple (e.g., Fig. 19). Dorsal surface with or without sparse setae. Antennal club of male and female subequal to or slightly longer than segments 2-7
.
.
.
6

Bolax rutila

Eunanus murinus
Figure 19
Figure 20
Figures 19-20. Head in dorsal view showing form of clypeus, mouthparts, and eye size in: 19) Bolax rutila, 20) Eunanus murinus.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
6(5).
.
.
. 		Length of antennal club half or less than half length of first antennal segment (Figs. 5, 23). Clypeal apex (in lateral view) sloped 45º with respect to dorsal plane of clypeus (Figs. 23, 36). Male tarsomeres simple, not flattened and dilated (Fig. 32)
.
.
Geniatosoma Costa Lima
 

6'.
.
.
.

Length of antennal club more than half length of first antennal segment. Clypeal apex (in lateral view) sloped 60-90º with respect to dorsal plane of clypeus (Fig. 37). Male tarsomeres dorsoventrally flattened and dilated (e.g., Fig. 34)
.
.
.
7
Figure 23
Figure 32
Figure 34
Figure 5
Figure 36
Figure 37
Figure 5. Geniatosoma nigrum (male). Figure 23. Head in dorsal view showing form of clypeus, mouthparts, and eye size in Geniatosoma lindemannae. Figures 32, 34. Male forelegs (dorsal view) showing comparison of tibial apex, protarsomeres, and claws of: 32) Geniatosoma lindemannae, 34) Trizogeniates temporalis. Figures 36-37. Head and apex of thorax in lateral view showing: 36) Clypeal apex sloped 45º with respect to dorsal plane of clypeus in Geniatosoma lindemannae (male) and 37) Clypeal apex sloped 60–90º with respect to dorsal plane of clypeus in Trizogeniates tibialis.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
7(6).
.
.
Form of clypeus parabolic, apex not reflexed (Fig. 24). Mandible exposed, apex narrowly rounded (Fig. 24). Male with all claws appearing simple on all legs
 

7'.
.
.
.

Form of clypeus not parabolic (instead rounded, quadrate), apex reflexed (e.g., Figs. 19-20, 22, 25-26). Mandible exposed or not, apex broadly rounded (e.g., Figs. 19, 23, 25). Male with claws obviously toothed on some or all legs
.
.
.
8

Bolax rutila

Eunanus murinus

Geniates borellii

Geniatosoma lindemannae
Figure 19
Figure 20
Figure 22
Figure 23

Heterogeniates bonariensis

Leucothyreus kirbyanus

Trizogeniates tibialis
Figure 24
Figure 25
Figure 26
Figures 19-26. Head in dorsal view showing form of clypeus, mouthparts, and eye size in: 19) Bolax rutila, 20) Eunanus murinus, 22) Geniates borellii, 23) Geniatosoma lindemannae, 24) Heterogeniates bonariensis (male), 25) Leucothyreus kirbyanus, 26) Trizogeniates tibialis.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

8(7).
.
.
.

Length of protarsomeres 2-4 subequal in length to protarsomere 5 (Fig. 31). Clypeus of male with lateral margins expanded, apex quadrate (Fig. 21); clypeus of female with lateral margins parallel, apex quadrate


. .
Evanos Ohaus
 

8'.
.
.
.

 Length of protarsomeres 2-4 greater than length of protarsomere 5 (Figs. 30, 33-34). Clypeus of male and female with lateral margins constricted, apex rounded or trapezoidal (e.g., Figs. 19, 22, 25-28)
.
.
.
9

Bolax

Evanos

Geniates

Leucothyreus
Figure 19
Figure 21
Figure 22
Figure 25

Trizogeniates

Geniates borellii

Geniates cornutus
Figure 26
Figure 27
Figure 28

Bolax

Evanos

Microchilus

Trizogeniates
Figure 30
Figure 31
Figure 33
Figure 34

Figures 19-26. Head in dorsal view showing form of clypeus, mouthparts, and eye size in: 19) Bolax rutila, 21) Evanos villatus (male),22) Geniates borellii, 25) Leucothyreus kirbyanus, 26) Trizogeniates tibialis. Figures 27-28. Head and pronotum in dorsal view showing form in: 27) Geniates borellii, male (head lacking tubercle, pronotum lacking concavity), 28) Geniates cornutus, male (head with tubercle, pronotum with concavity). Figures 30-34. Male forelegs (dorsal view) showing comparison of tibial apex, rotarsomeres, and claws of: 30) Bolax magna, 31) Evanos villatus, 33) Microchilus lineatus, and 34) Trizogeniates temporalis.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
9(8).
. 		Elytral margin with deep, setose punctures on lateral edge from apex of metepisternum to apex of elytra (Figs. 45a-b, 46a-b)

.
10
 

9'.
.

Elytral margin without deep, setose punctures on lateral edge from apex of metepisternum to apex of elytra
.
11
Trizogeniates foveicollis
Geniates cylindricus
Figure 45
Figure 46

Figures 45-46. Left elytral epipleuron showing: 45) dorsal view of stridulatory ridge in T. foveicollis (a) and ventral view of stridulatory ridge in T. foveicollis (b), 46) dorsal view of elytral epipleuron without stridulatory ridge in G. cylindricus (a) and ventral view of elytral epipleuron without stridulatory ridge in G. cylindricus (b).
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
10(9).
.
. 		Elytral margin with well-developed stridulatory ridge and with rigid stridulatory setae (Fig. 45a-b). Apex of metafemur (dorsal view) with stridulatory patch (Fig. 35)
 

10'.
.
.

Elytral margin lacking stridulatory ridge and without rigid stridulatory setae (Fig. 46a-b). Apex of metafemur (dorsal view) lacking stridulatory patch
.
Geniates
Ohaus
Figure 35
Figure 45
Figure 46

Figure 35. Hind leg (dorsal view) of Trizogeniates temporalis showing location of stridulatory file at the apex of the metafemur.Figures 45-46. Left elytral epipleuron showing: 45) dorsal view of stridulatory ridge in T. foveicollis (a) and ventral view of stridulatory ridge in T. foveicollis (b), 46) dorsal view of elytral epipleuron without stridulatory ridge in G. cylindricus (a) and ventral view of elytral epipleuron without stridulatory ridge in G. cylindricus (b).
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
11(9).
. 		Eyes small, interocular width greater than 6 transverse eye diameters (e.g., Fig. 19)
.
12
 

11'.
.

Eyes larger, interocular width less than 5 transverse eye diameters (e.g., Fig. 25)
Leucothyreus MacLeay
Bolax

Leucothyreus
Figure 19
Figure 25
Figures 19, 25. Head in dorsal view showing form of clypeus, mouthparts, and eye size in: 19) Bolax rutila, 25) Leucothyreus kirbyanus,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
12(11).
.
. 		Protarsomere 5 dorsoventrally flattened, width more than half length (Fig. 30). Length of body from apex of clypeus to apex of elytra more than 9.0 mm
Bolax
Fischer von Waldheim

Figure 30. Male foreleg (dorsal view) showing comparison of tibial apex, rotarsomeres,
and claws of Bolax magna

12'.
.
.

Protarsomere 5 dorsoventrally flattened or not; if flattened, then width less than half length. Length of body from apex of clypeus to apex of elytra less than 9.0 mm
.
Microchilus Blanchard
 
 
 
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UNL State Museum - Division of Entomology