Chariodema Blanchard, 1850

Katovich, Kerry, 2008, A generic-level phylogenetic review of the Macrodactylini (Coleoptera: Scarabaeidae: Melolonthinae), Insecta Mundi 2008 (23), pp. 1-78 : 32-33

Chariodema Blanchard, 1850

( Figure 58-62 )

Chariodema Blanchard, 1850: 117 . Type species Philochloenia virescens Blanchard, 1850 , by subsequent designation ( Evans 2003: 247).

Taxonomic Notes

The following generic diagnosis is based on a dissected homeotype of the presumptive syntype of C. xylina Blanchard located at the MNHC and identified with a Blanchard label. The generic type of C. virescens Blanchard was located at the MNHC, identified by a Blanchard label. The generic limits of the genus were compared to C. xylina .

Generic diagnosis

This genus is characterized by the wide, hexagonal pronotum; elongate prementum, with ventral surface medially grooved; elytra with strong anterior umbones, weak posterior umbones.

Generic redescription

Measurements: Prothorax at widest point 3.0 mm, elytra at widest point 3.7 mm, length 8.6 mm.

Color and vestiture: Body brown, surface with a vestiture consisting of short white setae.

Head: Clypeus not coplanar with frons; frons angled with clypeus at 20 o; labrum in frontal view trapezoidal, broad, weakly emarginate, labrum evenly transitioning with clypeus; labium with prementum quadrate, ventral surface with medial groove, ventromedially forming a weak U-shaped pocket, ventroposterior region flattened, ventromedially with an incomplete raised transverse ridge ( Fig. 60 ); mandible in dorsal view rectangular, scissorial area bluntly produced, bidentate, strongly deflexed dorsally, molar area well developed, bluntly produced adorally; maxillary palpi with apical palpus ovate, equal to length of 2 nd segment, apex acute, distally with a small sensory spot; antennae with 9 antennomeres, antennomeres 7-9 forming the elongate club, lamellae thin, equal to length of antennomeres 2-6 combined.

Prothorax: Pronotum hexagonal, oblong, transverse, widest medially, anterior angle acute, lateral margin convex, posterior angle obtuse, posterior margin convex, dorsal surface rounded, with a weak medial groove ( Fig. 61 ); prothoracic leg with coxa transverse; tibia bidentate, spur present in other species; pretarsus with claws missing in C. virescens , in C. xylina , claws are weakly divergent, equal in length, both claws are narrowly split, upper lobe narrow, lower lobe broad on individual claw.

Mesothorax: Scutellum subtriangular; elytra longer than wide, widest medially ( Fig. 62 ), elytral epipleuron narrowly flattened, margin lacking a membrane, dorsal surface lacking striae, anterior umbone strongly developed, posterior umbone weakly developed; pretarsus similar to prothoracic pretarsus.

Metathorax: Coxa widely separated; femur narrowly ovate, narrow proximally, width uniform; tibia subtriangular, narrow proximally, widest distally, posteroventral margin with a pair of long, stout spurs, anterior spur shorter than posterior spur, spurs arising from same level as tarsal articulation joint, posterior margin with a deep U-shaped tarsal articulation groove; pretarsus with claws similar to prothoracic legs.

Abdomen: Ventrites 2-4 subequal in length, 5 th visible ventrite (= propygidium) equal to length of 4 th, ventrite and sternite of 5 th abdominal segment not separated by a suture, spiracle placed medially, 6 th ventrite equal in length to 2X 5 th ventrite length, posteromedial margin membranous; pygidium subtriangular, longer than wide, posterior margin rounded.

Diversity and Geographic distribution

Chariodema contains 12 species, distributed from Bolivia, Brazil, and Colombia. There is no species

level key currently available for this genus.

Figures

Figure 58-62. Chariodema virescens (Blanchard). 58) Dorsal habitus. 59) Left lateral view. 60) Prementum, ligula and labial palpi, ventral view. 61) Pronotum, dorsal view. 62) Scutellum, and elytra, dorsal view.