Schizochelus Blanchard. Sixteen 1850
Creators: name: Katovich, Kerry
Publisher: name: Zenodo
Year: 2008
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Melolonthidae
Schizochelus

description: Schizochelus Blanchard, 1850   
(Figure 161-166)  
 Schizochelus Blanchard, 1850: 89. Type species Schizochelus flavescens Blanchard, 1850, by subsequent designation (Evans 2003: 346).   
 Taxonomic Notes   
 The following generic diagnosis is based on a dissected homeotype of the presumptive syntype of the type species S. flavescens located at the MNHC, identified with a Blanchard label.   
 Generic diagnosis   
 This genus is similar in appearance to Macrodactylus, but can be characterized by its oblong, transverse pronotum, widest in anterior 1/4.   
 Generic redescription   
 Measurements: Prothorax at widest point of prothorax 2.5 mm, elytra at widest point of elytra 3.2 mm.   
 Color and vestiture: Body brown, elytral surface with a vestiture consisting of dense yellow setae, remaining surface of body with scattered yellowish setae.   
 Head: Clypeus not coplanar with frons; frons angled at 30 o; labrum in frontal view, narrowly ovate, weakly emarginate, labrum coplanar with clypeus; labium with prementum rectangular, elongate (2X longer than wide), ventral surface with medial groove (Fig. 163); mandibles in dorsal view rectangular, scissorial area reduced to a membrane, lined with dense setae, molar area bluntly produced, weakly sclerotized; maxillary palpi with apical palpus ovate, equal to length of segments 2-3 combined, apex acute, with blunt sensory region; antennae with 10 antennomeres, antennomeres 7-9 forming the elongate club, lamellae thin, equal to length of antennomeres 2-7 combined.   
 Prothorax: Pronotum oblong, transverse, wider than long, widest in anterior 1/4, anterior angle acute, lateral margin convex, posterior angle acute, posterior margin concave, medially lobed (Fig. 164); prothoracic leg with coxa elongate; tibia lacking tooth, ventral margin medially with a spur (Fig. 165); pretarsus with claws divergent, equal in length, both claws narrowly split, upper lobe narrow, slightly longer than lower lobe, lower lobe narrow on individual claw, base of claw toothed.   
 Mesothorax: Scutellum narrowly subtriangular; elytra longer than wide, widest medially, in lateral profile epipleuron flattened, membranous, dorsal surface with six weakly raised striae, anterior and posterior umbones strongly developed; pretarsus similar to prothoracic pretarsus.   
 Metathorax: Metathoracic leg with coxa widely separated; femur narrowly ovate, narrow proximally, widest medially; tibia subtriangular, narrow proximally, widest medially, posteroventral margin lacking spurs, posterior margin with a deep, U-shaped groove; pretarsus with claws similar to those of prothoracic and mesothoracic legs.   
 Abdomen: Ventrites 2-4 subequal in length, medially grooved (Fig. 166), 5 th visible ventrite (= propygidium) equal to length of ventrites 3-4 combined, posterior margin membrane-like, ventrite and sternite of 5 th abdominal segment lacking suture, spiracle placed posteromedially, 6 th ventrite equal to length of 5 th ventrite, triangular in lateral profile; pygidium subtriangular, width equal to length, posterior margin rounded.   
 Diversity and Geographic Distribution Schizochelus comprises seven species, all known only from Brazil or Chile. No key to species exists.
description: Published as part of Katovich, Kerry, 2008, A generic-level phylogenetic review of the Macrodactylini (Coleoptera: Scarabaeidae: Melolonthinae), pp. 1-78 in Insecta Mundi 2008 (23) on pages 62-64, DOI: 10.5281/zenodo.4532645