Paxillus

Mattos, Ingrid & Mermudes, José Ricardo M., 2013, Synopsis of Paxillus MacLeay, 1819 (Coleoptera: Passalidae): distributional records and descriptions of four new species from Brazil, Zootaxa 3652 (3), pp. 327-342 : 340

Key to the species of Paxillus

1. Central tubercle short; disc of metasternum delimited by punctures or group of punctures in the median and posterior lateral area................................................................................................ 3

- Central tubercle elongate; disc of metasternum not delimited, lacking defined margins.............................. 2

2. Central tubercle long, exceeding the frontal margin, apex completely free......... P. macrocerus Reyes-Castillo & Fonseca

- Central tubercle large and flat, not exceeding the frontal margin, apex free.. P. corniculatus Fonseca, Gouveia , & Fernandes

3. Secondary median frontal tubercles evident on the anterior margin of the head.................................... 4

- Secondary median frontal tubercles absent................................................................. 6

4. Hypostomal process opaque and with short setae at apex...................... P. amazonicus Reyes-Castillo & Fonseca

- Hypostomal process shiny and glabrous at apex.............................................................. 5

5. Mesosternal scar oval, weakly evident and shiny; metasternal fossae glabrous.................... P. forsteri Luederwaldt

- Mesosternal scar elongate and narrow, rugose inside; metasternal fossae pubescent............... P. pleuralis Luederwaldt

6. Mesosternal scar punctate, with punctures exceeding the border of scar......................... P. camerani (Rosmini)

- Mesosternal scar smooth, impunctate...................................................................... 7

7. Antennal club with short antennomeres, the first antennomere short, reduced..................... P. jamaicensis Hincks

- Antennal club with elongate antennomeres................................................................ 8

8. Prosternal process smooth; scape either lacking dorsal spine or ventrally impressed, without setae.................... 9

- Prosternal process strongly impressed and opaque medially, with shallow, irregular, confluent punctures; scape with dorsal subapical spine and ventrally impressed with sparse setae.............. P. chapadensis Mattos & Mermudes , new species

9. Medial frontal tubercles almost connected with the anterior angles of head. Frontal area with anterior margin almost straight. Antennal club with anterior margin straight or almost straight (when closed)........................ P. leachi MacLeay

- Medial frontal tubercles distinctly separated from anterior angles of head. Frontal area with anterior margin from feebly con- cave to straight. Antennal club with anterior margin weakly convex (when closed)................................ 10

10. Anterior margin of head with anterior angles forward; mesosternal scar oval and microcorrugated.... P. borellii (Pangella)

- Anterior margin of head with anterior angles downward; mesosternal scar elongate............................... 11

11. Scutellum grooved................................................................................... 12

- Scutellum smooth................................................................................... 13

12. Labrum with anterior margin almost straight; central tubercle somewhat less dilated at base and merged with posterior lateral tubercles..................................................... P. manausensis Mattos & Mermudes , new species

- Labrum with anterior margin slightly concave; central tubercle wider at base and continuous with posterior lateral tubercles.............................................................. P. uaupesensis Mattos & Mermudes , new species

13. Mesosternal scar straight, wide and deep................................ P. re y e s i Mattos & Mermudes, new species

- Mesosternal scar oval, widely sinuate......................................... P. pentaphyllus (Palisot de Beauvois)