Agamopus Bates, 1887

Costa-Silva, Vinícius, Carvalho, Edrielly & Vaz-De, Fernando Z., 2022, A taxonomic revision of the New World genus Agamopus Bates, 1887 (Coleoptera: Scarabaeinae: Ateuchini), European Journal of Taxonomy 806 (1), pp. 64-89 : 67-83

Genus Agamopus Bates, 1887

Agamopus Bates, 1887: 42 (original description).

Agamopus – Gillet 1911: 49 (catalogue). — Blackwelder 1944: 203 (catalogue); 1973: 6 (catalogue). — Pereira 1947: 4 (key to species); 1954: 56 (key to the genera of American Dichotomiina). — Halffter & Martínez 1968: 226 (taxonomic revision). — Howden & Young 1981: 40 (diagnosis). — Medina & Lopera-Toro 2000: 301, 306 (key to the Scarabaeinae of Colombia). — Medina et al. 2001: 133 (dung beetle species from Colombia). — Halffter 2003: 24 (redescription). — Vaz-de- Mello et al. 2011: 4, 8, 15, 23, 30, 38, 44 (key to the genera of Scarabaeinae ). — Boilly & Vaz-de- Mello 2013: 106 (key to the Scarabaeinae of Guiana). — Cupello & Vaz-de-Mello 2018: 13, 17 (list of genus-group names proposed for ‘ Canthon sensu lato’).

Type species

Agamopus lampros Bates, 1887 , by original monotypy.

Diagnosis

Agamopus belongs to the tribe Ateuchini , which is recognized by the transverse clypeal process; hypomeron with a transverse carina and deep anterior excavation; apex of protibiae truncated in a straight angle (see Vaz-de-Mello 2008); metatibiae of males with an elongate apical process ( Figs 4C – black arrow; 6A, C); and by the transverse sulcus on the pygidium (as in Figs 4D and 9E ). The latter two characters can be used to separate Agamopus from all other genera in the tribe ( Halffter & Martínez 1968; Howden & Young 1981; Vaz-de-Mello et al. 2011; Boilly & Vaz-de-Mello 2013). For a comprehensive description of the genus Agamopus , see Halffter & Martínez (1968) and Howden & Young (1981).

Identification key to the Agamopus species (adapted from Halffter & Martínez 1968)

1. Frons with two small tubercles near to fronto-clypeal sulcus ( Fig. 5B , white setae). Pygidium without yellow setae ...................................................................................................................................... 2

– Frons without tubercles ( Fig. 5A ). Pygidium bearing yellow setae ( Fig. 2A‒B ) ............................. 3

2. Pygidium with arched sulcus ( Fig. 9E ). Anterior half of metatibiae with outer and inner edges gradually widened apically; inner edge smooth. Central Brazil......................................................... ................................................................................................... Agamopus viridis Boucomont, 1928

– Pygidium with sinuous sulcus ( Fig. 4D ). Anterior half of metatibiae with outer and inner edges parallel ( Fig. 4C ); inner edge crenulated. Southern Brazil (Paraná) .......... Agamopus joker sp. nov.

3. Head fully covered by micropunctation (as in Fig 5B , but without tubercles); male with posterior margin of metafemora smooth .......................................................................................................... 4

– Head with central part smooth or with sparse micropunctation ( Fig. 5A ); male with posterior edge of metafemora crenulated ( Fig. 6C ). From Mexico to northern South America ( Colombia and Venezuela) ........................................................................................ Agamopus lampros Bates, 1887

4. Pygidium with a single row of several yellow setae arranged along anterior edge of sulcus ( Fig. 2A ); Brazil and Bolivia............................................................... Agamopus unguicularis ( Harold, 1883)

– Pygidium with a row of two or three yellow setae along centre of anterior edge of sulcus ( Fig. 2B ). Suriname, French Guiana, and northern Brazil...................... Agamopus castaneus Balthasar, 1938

Figures

Fig. 4. Agamopus joker sp. nov. Holotype, ♂ (CEMT). A. Habitus, dorsal view. B. Habitus, ventral view (black arrow indicating the longitudinal keel slightly marked). C. Hind tibia (black arrow indicating the elongate apical process in the metatibia). D. Sulcus in the pygidium. E. Aedeagus, lateral view (black arrow indicating the gibbosity near base). F. Aedeagus, dorsal view. G. Labels. Scale bars = 1 mm.

Fig. 9. A‒D. Agamopus viridis Boucomont, 1928. Holotype, ♀ (MNHN). A. Habitus, dorsal view. B. Habitus, ventral view. C. Habitus, lateral view. D. Labels. E. Sulcus of the pygidium in an ordinary specimen (CEMT). Photographs A‒D: Christophe Rivier, MNHN.

Fig. 5. Cephalic integument of species of Agamopus Bates, 1887. A. A. lampros Bates, 1887 (CEMT): smooth and lacking tubercles.B. A. joker sp. nov., holotype, ♂ (CEMT), with dense punctuation and two small tubercles. White arrows indicating the small cephalic tubercles. Red arrows indicating the lateral clypeal carina. Scale bars = 1 mm.

Fig. 2. Ventral view of the abdomen. A. Agamopus unguicularis (Harold, 1883), dissected specimen (CEMT), with one row of several yellow setae along the anterior edge of the pygidial sulcus (black arrows). B. Agamopus castaneus Balthasar, 1938, dissected specimen (CEMT) with three (sometimes two) yellow setae in the centre of the pygidial disc (black arrows). Scale bars = 1 mm.

Fig. 6. Agamopus lamprosBates, 1887. A–B. Lectotype, ♂ (BMNH). A. Habitus, dorsal view. B. Labels. C. Hind leg of a non-type specimen (CEMT) showing the posterior femoral edge crenulate (black arrows). Length of specimen: 4.5 mm. Scale bar = 1 mm.