Homonyx Guerin-Meneville , 1839

Moore, Matthew R., Jameson, Mary L., Garner, Beulah H., Audibert, Cedric, Smith, Andrew B. T. & Seidel, Matthias, 2017, Synopsis of the pelidnotine scarabs (Coleoptera, Scarabaeidae, Rutelinae, Rutelini) and annotated catalog of the species and subspecies, ZooKeys 666, pp. 1-349 : 1

Homonyx Guerin-Meneville, 1839 Figs 1F , 3A , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33

Type species.

Homonyx cupreus Guérin-Méneville, 1839.

Species.

14 species and subspecies; length 12-19 mm.

Species in the genus Homonyx are elongate, parallel-sided, subcylindrical, and dark-colored beetles. They strongly resemble the allied genus Parhomonyx but can be separated based on the form of the mandibles (bidentate in Homonyx and broadly rounded with one apical tooth in Parhomonyx ), the apex of the metatibia (with many spinules in Parhomonyx and biemarginate in Homonyx ), and the feathery fringe of setae at the apex of the elytra (exposed in Parhomonyx ; hidden in Homonyx ). These genera share additional characters: prosternal process short (well-developed in H. planicostatus ); mesosternum not produced beyond the mesometasternal suture; pronotum with bead complete apically, laterally, and basally; claws simple; lateral set of setae on apical edge of 3rd metatarsomere of unequal length and width (versus equal in length and width in Catoclastus ).

Species in the genus are distributed in Argentina, Brazil, Bolivia, Ecuador, Uruguay, and Peru. Soula (2010a) provides the most current treatment of species in the genus, but did not include a key for identification. Larvae, sister-group relationships and natural history are poorly known for species in the genus.

Figures

Figure 1. Clypeal shape varying from rounded, parabolic, trapezoidal, subquadrate (A-D), and emarginate (E-F). Lateral edge of mandibles with no reflexed teeth (lacking teeth in A, but the mandible is reflexed rather than flattened in A, two reflexed teeth (B, E, F), or one reflexed tooth (C )). Apical bead of pronotum varying from obsolete (A) to complete medially (B, C, D, F). Disc of frons with V-shaped depression (E) or frons planar, smooth, lacking V-shaped depression (A-D, F) A Chrysina beyeri Skinner B Epichalcoplethis velutipes velutipes (Arrow) C Parhomonyx fuscoaeneus (Ohaus) D Chipita mexicana (Ohaus) E Sorocha sp. F Homonyx elongatus (Blanchard).

Figure 3. Characters of the thorax (ventral view) and elytral apex (dorsal and lateral views). Mesosternal keel not surpassing base of mesocoxae (A) or keel surpassing base of mesocoxae (B). Acute, spiniform projections at apex of elytra (C, D). A Homonyx elongatus B Pelidnota dobleri Frey C Mesomerodon gilletti, dorsal view D Mesomerodon gilletti, lateral view.

Figure 26. Homonyx bahianus Ohaus (valid name H. chalceus bahianus) type male (see " Type specimens and lectotype designation " in Methods) from ZMHB. A Dorsal habitus B Lateral habitus C Specimen labels, mouthparts, and genitalia D Male genitalia, lateral view E Parameres, caudal view.

Figure 27. Homonyx chalceus Blanchard male (male specimen compared [by Ohaus] with Blanchard's type deposited at MNHN). A Dorsal habitus B Lateral habitus C Male genitalia, lateral view D Specimen labels and male genitalia.

Figure 28. Homonyx feyeri Ohaus holotype male from ZMHB. A Dorsal habitus B Lateral habitus C Specimen labels, mouthparts, and male genitalia D Male genitalia, lateral view E Parameres, caudal view.

Figure 29. Homonyx chalceus var. fuscocupreus Ohaus (valid name H. fuscocupreus) type male from ZMHB. A Dorsal habitus B Lateral habitus C Specimens labels D Parameres, caudal view.

Figure 30. Homonyx planicostatus peruanus Ohaus (valid name H. peruanus) syntype female from ZMHB. A Dorsal habitus B Lateral habitus C Specimen labels and mouthparts.

Figure 31. Homonyx planicostatus Blanchard (male specimen compared [by Ohaus] with Blanchard's type from MNHN). A Dorsal habitus B Lateral habitus C Specimen labels and male genitalia D Male genitalia, lateral view E Male parameres, caudal view.

Figure 32. Homonyx chalceus santiagensis Ohaus (valid name H. santiagensis) type male (see " Type specimens and lectotype designation " in Methods) from ZMHB. A Dorsal habitus B Lateral habitus C Specimens labels and male genitalia D Male genitalia, lateral view E Parameres, caudal view.

Figure 33. Homonyx chalceus uruguayanus Ohaus (valid name H. uruguayanus) syntype male from ZMHB. A Dorsal habitus B Lateral habitus C Specimens labels and male genitalia D Male genitalia, lateral view E Parameres, caudal view.