Gromphas amazonica Bates, 1870

Figueroa, Luis, Edmonds, W. D. & Meza-Velez, Felipe, 2012, The genus Gromphas Brullé, 1837 in Peru (Coleoptera: Scarabaeidae: Scarabaeinae: Phanaeini), Insecta Mundi 2012 (248), pp. 1-8 : 3-4

Gromphas amazonica Bates, 1870

( Fig. 3-4, 12-13, 19-23)

Diagnosis. Length 12-18 mm. Dorsum shining black with weak dark green to blue highlights ( Fig. 3-4). Clypeal margin slightly expanded and upturned near notch ( Fig. 12, arrow), not evenly curved. Head of both sexes with a weakly bituberculate, median gibbosity, never with a conical horn ( Fig. 12). Pronotum of both sexes evenly convex, lacking any trace of a median prominence ( Fig. 3-4). Pronotum densely and finely granulate, granulation becoming almost effaced posteromedially. Inner apical angle of male protibia drawn out into an acute spine ( Fig. 20, arrow); outer edge of protibial spur of both sexes strongly expanded subapically ( Fig. 20-21). Apical protarsal segment prolonged apically ( Fig. 19).

Geographical Distribution. ( Fig. 5) Recorded from Brazil, Colombia and Peru. In Peru known from isolated localities in Amazonian lowlands of Loreto, San Martin and Ucayali. Peruvian collecting data: LORETO: Prov. Ucayali, Distr. Padre Marquez, CCNN Santa Ana (7 o 52’S, 75 o 31' W) 224 m [Oct] MUSM ; Contamana (7 o 21’S, 75 o 01’W) 134 m [Dec] MUSM, WDEC. SAN MARTIN: Prov. El Porvenir ,

Bosque El Pelejo (6 o 16’S, 75 o 50’W) 161 m [May] MUSM. UCAYALI: Prov. Coronel Portillo, Pucallpa (8 o 25’S, 74 o 28’W) [Aug] MUSM, (8 o 22’S, 74 o 34’W) [Jul-Aug, Dec] CMNC.

Ecology. The ecology of this species is not understood. Specimens examined with precise data were collected with pitfall traps baited with human feces in forest habitats; in one case, several individuals were found in secondary growth associated with mandioca cultivation (cassava, “yuca”; Manihot esculenta Crantz ). Trond Larsen (pers. comm.) points out the possibility that it may be a narrow ecological specialist; he has not collected G. amazonica during several years of intensive collection and ecological monitoring of the dung beetle fauna in Madre de Díos (southeastern Peru).