Scarabaeinae, Latreille, 1802

Ratcliffe, Brett C., 2013, The Dung- and Carrion-Feeding Scarabs (Coleoptera: Scarabaeoidea) of an Amazonian Blackwater Rainforest: Results of a Continuous, 56 - Week, Baited-PitfallTrap Study, The Coleopterists Bulletin 67 (4), pp. 481-520 : 507-510

Scarabaeinae : Canthonini

Canthon ( Figs. 38–39 ) consists of about 150 species found from Canada to Argentina ( Gill 2002). Three species of Canthon were taken at Reserva Ducke, with C. triangularis being the most abundant ( Table 1). Canthon triangularis ( Fig. 39 , frontispiece) (Amazonian parts of Brazil, Suriname, French Guiana, Colombia, Bolivia) is diurnal, often seen resting on leaves, and is a dung roller; it represented 85% of all Canthon collected in the dung traps and 15% taken in the carrion traps.

Canthonella Chapin is a small genus of 16 species that occur in the West Indies and South America (Ratcliffe and Smith 1999). Matthews (1965) observed them opportunistically feeding on bird, snail, and mammal dung, and the five specimens of Canthonella silphoides (Harold) taken in this study were collected in both dung and carrion traps ( Table 1).

Cryptocanthon Balthasar ( Fig. 40 ) is another small genus with 35 species occurring from Mexico to Brazil ( Cook 2002). They inhabit the litter of lowland rainforests and montane cloud forests. Cryptocanthon peckorum Howden ( Brazil, Colombia, Bolivia; Cook 2002) was col- lected in both dung (89%) and carrion traps (11%) at Reserva Ducke ( Table 1).

Deltochilum Eschscholtz ( Figs. 41–43 ) is a New World genus with more than 80 species ( Gill 2002). Most species feed on carrion, but all five species taken at Reserva Ducke were also collected in the dung traps. Interestingly, the few specimens of Deltochilum orbiculare Lansberge were collected only in the dung traps. Deltochilum diringshofeni ( Brazil) (61% on carrion) and D. septemstriatum ( French Guiana, Brazil) (78% on carrion) were the two most abundant species of Deltochilum at Reserva Ducke ( Table 1).

Scybalocanthon Martínez has approximately 19 species that occur in Central and South America ( Silva 2011). Molano Rendón and Medina Uribe (2010) reported Scybalocanthon species are usually diurnal, and that they are known to feed on vertebrate dung preferentially but also on carrion and fungi. Scybalocanthon pygidialis (Schmidt) ( Brazil, Colombia, Suriname) was collected from both dung (92%) and carrion traps (8%) at Reserva Ducke ( Table 1).

Figures

Figs. 35–40. Reserva Ducke dung beetles. 35) Onthophagus bidentatus. Photograph by Denis Faure; 36) Onthophagus rubrescens. Photograph by Trond Larsen; 37) Eurysternus caribaeus. Photograph by Trond Larsen; 38) Canthon quadriguttatus rolling a small piece of howler dung spattered on a leaf about 1 m above the ground. Photograph by Trond Larsen; 39) Canthon triangularis. Photograph by Trond Larsen; 40) Cryptocanthon peckorum. Photograph by Trond Larsen. All images used by permission.

Figs. 41–46. Reserva Ducke dung beetles. 41) Deltochilum carinatum. Photograph by Jim McClarin; 42) Deltochilum septemstriatum. Photograph by Denis Faure; 43) Deltochilum pseudoicarus. Photograph by Trond Larsen; 44) Ateuchus sp. Photograph by Jim McClarin; 45) Canthidium bicolor with phoretic mite. Photograph by Trond Larsen; 46) Canthidium gerstaeckeri. Photograph by Trond Larsen. All images used by permission.