Glaresis clypeata Van Dyke, 1928

Gordon, Robert D. & Hanley, Guy A., 2014, Systematic revision of American Glaresidae (Coleoptera: Scarabaeoidea), Insecta Mundi 2014 (333), pp. 1-91 : 19-20

Glaresis clypeata Van Dyke

Glaresis clypeata Van Dyke 1928: 162 ; Gordon 1970: 507.

Description. Male. Length 3.5 mm, width 1.8 mm; body form robust, slightly widened from elytral base to apical 1/3 ( Fig. 11A ). Color dark yellowish brown. Entire head surface densely microreticulate, dull, clypeus and frons with large tubercles separated by less than to twice diameter of a tubercle, setae short, barely visible. Clypeal apex broadly, weakly emarginate medially, not sinuate, with large, evenly spaced tubercles, appearing dentate, lateral angles oblique, pronounced, outwardly acute ( Fig. 11B ). Mandible pair symmetrical; mesal tooth strong; lateral prominence strong, pronounced; outer margin abruptly rounded. Pronotum with all foveae weakly impressed except fovea on each side medially near lateral margin strongly impressed; surface densely rugose, with sparse, setae-bearing carinae, carinae short, straight. Elytra with surface dull, densely microreticulate; striae convex, feebly carinate, carinal segments widely separated, each with short seta; intervals with shallow, slightly rectangular punctures ( Fig. 11E ) Metasternum long, dull, finely, densely microreticulate, surface medially flat without median carina, lateral surface with sparse, short ridges each bearing seta twice as long as ridge ( Fig. 11D ); metasternal groove nearly invisible. Lateral protibial teeth unevenly spaced, basal 2 teeth close together. Mesotibia with 6 spines laterally, tibia weakly projecting at apex ( Fig.11D ). Posterior metatrochanteral margin with 3 small, blunt teeth ( Fig. 11D ); posterosuperior surface of metatrochanter with 2 teeth, outer tooth large, inner tooth small ( Fig. 11H ). Metafemoral surface microreticulate with widely scattered, elongate, setae-bearing ridges, ridges often becoming tuberculate in large specimens, projecting above metafemoral surface along posterior metafemoral margin; width to length ratio 1.0:1.6, with narrow flange on anterior margin; posterior margin with single large tooth at angle near metatrochanter ( Fig. 11H ), posterosuperior margin with 2 teeth. Metatibia broadly triangular, surface entirely microreticulate, with small, equal teeth from base to large, bifid, posteromedian lateral projection ( Fig. 11G ), row of sparse, small tubercles extended from base nearly to apex medially, inner margin smooth, pubescent. Apex of 5th abdominal ventrite evenly rounded. Genitalia very long, basal piece short, 1/3 length of parameres, proximal end curved; median lobe slightly longer than parameres, not tapered from base to apex, slightly constricted medially, wider than paramere, apex broadly rounded, not curved upward before apex; parameres slightly curved in lateral view, apex narrow, somewhat acute ( Fig. 11F ).

Female. Apex of 5th abdominal ventrite same as in male.

Variation. Length 3.5 mm to 5.3 mm, width 1.8 to 3.8 mm. Apical clypeal teeth and surface tubercles on head extremely variable between populations, clypeal teeth may be small, relatively indistinct to very robust, and surface tubercles on head vary correspondingly; largest specimens tend to have exaggerated head sculpture and are usually from southern California or southern Arizona; posterolateral mesotibial spines vary from 5 to 9, spacing also varies.

Type locality. California, Trinity Co., Carrville.

Type depository. CASC.

Temporal distribution. April-October.

Geographical distribution. MEXICO. Baja California Norte: 5.5 mi. E El Arco. UNITED STATES. Arizona: Cochise Co., 5 mi. SW McNeal; Coconino Co., 2 mi. N. Sedona; 1 mi. E. Tuba City; Navajo Ind. Res., 1.2 mi. S. Moenkopi; Maricopa Co., Tempe; Mohave Co., Virgin River Rec. Area; Yavapai Co., Ash

Fork; 3 mi. SW Sedona; Yuma Co., Fort Yuma; Ehrenberg; Yuma Co., Parker. California: Imperial Co., Algodones Dunes, 2.5 mi. NE Coachella Bridge #1; Inyo Co., Independence; Lassen Co., Hat Creek, Lasen NF; Mono Co., Benton; Benton Sta.; Riverside Co., Indian Wells; Trinity Co., Carrville. Colorado: Nunn Co., Pawnee Grassland. Idaho: Ada Co., T1N R4E S29. Nevada: Lincoln Co., Alamo; Ormsby Co., Carson City; Nye Co., Amargosa Desert, Big Dune; 2 mi. N 24 mi. E Warm Springs, Black Rock Smt, 6350'; Grapevine Mts., Phinney Canyon; Pershing Co., Woolsey; Washoe Co., 9 mi. S. Reno. New Mexico: McKinley Co., Dalton Pass; Otero Co., Three Rivers Petroglyphs; San Juan Co., Cuaco Canyon. Oregon: Deschutes Co., 13 mi. E. Sisters; Morrow Co., 3 mi. S Boardman. Utah: Emery Co., Goblin Valley; Garfield Co., Calf Creek, 7 mi S Boulder; Grand Co., 3 mi N of Moab; Juab Co., Little Sahara, White Sands Camp; Kane Co., Coral Pink sand dunes; 50 mi. E. Kanab, Catstairs Canyon; Sevier Co., Fish Lake, Dog Spring; Toole Co., Dugway Proving Ground; Washington Co., Leeds Canyon; Wayne Co., 14 mi. S. Hanksville; Wayne Co., base of Henry Mts; Weber Co., Ogden. Washington: Yakima Co., Toppenish. Wyoming: Sweetwater Co., Flaming Gorge, Blacks Fork River; Sweetwater Co., Flaming Gorge Res. ( BYUC) ( CASC) ( CICC) ( CMNC) ( CMNH) ( CNIC) ( CSCA) ( JHCIC) ( MJPC) ( RCCC) ( SMCC) ( USNM) ( USUL)

Remarks. Glaresis clypeata is one of the most easily recognized species of North American Glaresis . The combination of large average size; strongly tuberculate head and clypeal apex; large, usually acute tooth on posterior femoral margin adjoining trochanter; and lateral metasternal ridges bearing setae twice as long as ridge diagnose this species.

Specimens available for examination indicate an extremely broad range from Mexico and Arizona north to Washington state. Additional field work should expand this range considerably.

Figures

Figures 11A-11H. Glaresis clypeata Van Dyke. A) Habitus view. B) Clypeus and head surface. C) Elytra. D) Metasternum and mesotibia. E) Elytral striae. F) Male genitalia. G) Metaleg and trochanter, dorsal view. H) Metaleg and trochanter, ventral view.