Bradypodidium, Vaz-De-Mello, 2008

Vaz-De-Mello, Fernando Z., 2008, Synopsis of the new subtribe Scatimina (Coleoptera: Scarabaeidae: Scarabaeinae: Ateuchini), with descriptions of twelve new genera and review of Genieridium, new genus, Zootaxa 1955, pp. 1-75 : 18-19

publication ID

1175­5334

persistent identifier

https://treatment.plazi.org/id/03D287CE-FFA5-AF08-D1DB-DC23FE1A1001

treatment provided by

Felipe

scientific name

Bradypodidium
status

gen. nov.

2. Bradypodidium View in CoL , new genus

Diagnosis: Small oval to elongate species ( Fig. 17), hairs very fine, clypeus with none, two or four teeth ( Figs. 43, 45), elytral striae deeper and wider posteriorly, protibial teeth concentrated in the apical one-half of tibia; males with proclaws and last tarsomere strongly modified ( Fig. 46); lacking apicomesal tooth in protibia; parameres elongated, flat and wider at apex, always with mesal apices superposed ( Fig. 44).

Description: Size 2.3–3.7 mm. Body oval, with elytra clearly wider than prothorax ( Fig. 17); color tan to black, rarely with traces of metallic sheen. Clypeus with none, two, or four teeth (interspecific and sexually dimorphic in at least some species related to a wide variety of general head forms: transverse, rounded, or triangularly elongated). Clypeal border lateral to teeth straight to feebly rounded, continuous with genal border. Clypeofrontal and clypeogenal sutures indistinct, head dorsally flat except for anteromedian part of clypeus. Eyes, in dorsal view oval; interocular width 8 to 10 times eye width ( Figs. 43, 45). Pronotum lacking anterior or posterior beads, lateral callosity weakly defined. Disc centrally with setose punctures. Hypomera laterally separated from pronotal disc by strong carina and bearing a strong posterior longitudinal carina parallel to the pronotal-hypomeral delimitation. Mesoepimera with anterior transverse carina. Metasternum with setose punctures on the disc. Elytral interstriae almost flat, each with two well-separated rows of setose punctures; striae wider and deeper on the posterior declivity. Pseudoepipleura gradually narrowed from anterior third to end of elytron, with setiferous punctures all along. Protibiae with three teeth, basal one frequently reduced; teeth concentrated in apical two-fifths of tibia; lateral tibial margin denticulate between base and basal tooth; ventral scale-like setae of tibial teeth absent. Mesotibiae and metatibiae elongate, much longer than five times their apical width. Metatarsus with first tarsomere flattened and oval, longer than second. Parameres bladelike, tips slightly overlapped, apically wider than at mid-length ( Fig. 44), about as long as half phallobase length or shorter. Coxites present, large and symmetrical. Spermatheca C-shaped, gradually narrowed posteriorly, basally globular and strongly modified in conical point at duct insertion.

Sexual dimorphism: Apical tarsomere of protarsi of male excavated dorsally to receive proclaws; claws strongly angulate at mid-length ( Fig. 46). Metasternal disc somewhat concave in males, and very flat in females. Protibial teeth much wider and robust in females; males frequently with very reduced basal tooth. In species with variable clypeal shape, males often with more elongated clypeus when teeth are present, and reduced or absent lateral clypeal teeth; while females almost always have transverse or rounded head with four well developed clypeal teeth. Pygidium much more transverse and vertical in females than in males.

Type species: Trichillum bradyporum Boucomont, 1928 View in CoL (present designation) = Bradypodidium bradyporum ( Boucomont, 1928) View in CoL , new combination.

Etymology: Combination of Bradypus (generic name of the most common sloths [ Mammalia: Edentata: Bradypodidae ], in reference to the phoretic relation these scarabs have with them) and Pedaridium , a genus name. Bradypodidium is neuter in gender.

Distribution: Widely co-distributed with sloths in the Neotropical region from Costa Rica to southeastern Brazil.

Remarks: Collection records suggest an obligatory relationship with sloths. Bradypodidium is closely related to Trichillidium , sharing with the latter protibial teeth concentrated in the apical half of tibia, slender dorsal setae, among many other characters. Monophyly of Bradypodidium is supported by the relatively slen- der male tibia in relation to female, laminate overlapped parameres, relatively elongated body, transverse pygidium in females, and the association with sloths. See under Onoreidium for more remarks on Trichillidium-Bradypodidium.

Composition: Besides the type species, the genus Bradypodidium includes B. adisi ( Ratcliffe, 1980) , new combination, B. venezuelense ( Ferreira & Galileo, 1993) , new combination, and at least three new species presently under study.

Material examined:

Kingdom

Animalia

Phylum

Arthropoda

Class

Insecta

Order

Coleoptera

Family

Scarabaeidae

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