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1. |
Larger mesotibial and metatibial apical spurs pectinate (Fig. 1); Body form elongate (Fig. 2). Restricted to western North America (only CA, OR). |
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1'.
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Larger mesotibial apical spur pectinate, both metatibial spurs simple; Body form oval (Fig. 3). Widely distributed. |
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![pectinate spur](images/pectinate spur.jpg) |
![Pseudochodaeus](images/Pseudochodaeus estriatus.jpg) |
![musculus](../../../../Xenochodaeus musculus.jpg) |
Fig. 1. Pectinate
apical spur. |
Fig. 2. Elongate body form of
Pseudochodaeus estriatus. |
Fig. 3. Oval body form of
Xenochodaeus musculus. |
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2. |
Anterior margin of pronotum not simply concave, instead margin produced behind eyes (Fig. 4). Antenna with 9 antennomeres. Mandibles angulate externally. |
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2'.
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Anterior margin of pronotum simply concave (Fig. 5). Antenna with 10 antennomeres. Mandibles evenly rounded externally. |
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Fig. 4. Modified anterior pronotal margin,
Cucochodaeus sparsus |
Fig. 5. Concave anterior pronotal margin,
Neochodaeus repandus. |
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3. |
Apex of elytra dentate, teeth interlocking with 2 tubercles on propygidial margin (Fig. 6). |
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3'.
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Apex of elytra not dentate, instead evenly rounded; propygidium lacking tubercles (sulcus may be present on surface). |
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Fig. 6. Dentate (pointed) elytral apices of Parochodaeus spp., with 2 interlocking tubercles on the propygidium. |
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4. |
Propygidium lacking sulcus. Male with mentum strongly produced Antennal club not strongly oval, last segment concave (Fig. 7). |
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4'.
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Propygidium with longitudinal sulcus (Figs. 9-10). Antennal club distinctly oval, last segment convex (Fig. 8). |
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![](images/repandusAntenna.jpg) |
Fig. 7. Right antenna of
Codocera gnatho, female. |
Fig. 8. Right antenna of
Neochodaeus repandus. |
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5. |
Propygidium long with elongate, subparallel sulcus (Fig. 9). Mentum distinctly longitudinally impressed from apex to base. |
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5'.
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Propygidium short, with trapezoidal sulcus (Fig. 10). Mentum flat, only weakly impressed apically. |
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![propygidium](images/Xeno propygidium.jpg) |
![pygidium](images/neopygidium.jpg) |
Fig.9. Propygidium of
Xenochodaeus spp. |
Fig. 10. Propygidium of
Neochodaeus spp. |
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