Glaresis inducta Horn, 1885

Gordon, Robert D. & Hanley, Guy A., 2014, Systematic revision of American Glaresidae (Coleoptera: Scarabaeoidea), Insecta Mundi 2014 (333), pp. 1-91 : 27-29

Glaresis inducta Horn

Glaresis inducta Horn 1885: 117 ; Gordon 1970: 510; Ratcliffe 1991: 133; Warner 1995: 268; Ratcliffe and Paulsen 2008: 65.

Glaresis knausi Brown 1928: 73 ; Gordon 1970: 510.

Glaresis cartwrighti Gordon 1970: 508 . New synonym.

Description. Male. Length 3.0 mm, width 1.8 mm; body form short, stout, strongly widened from elytral base to apical 1/3 ( Fig. 17A ). Color yellowish brown. Head with clypeal surface and apical 1/2 of frons shiny, posterior 1/2 of frons and vertex densely rugose, dull, clypeus and frons with large, scattered tubercles, vertex without basal carina, setae short, indistinct. Clypeal apex slightly raised, weakly sinuate, with median emargination, lateral angles oblique, angulate ( Fig. 17B ). Mandible pair symmetrical; mesal tooth strong; lateral prominence strong, outer margin rounded. Pronotum with distinct, long, transverse fovea in anterior 1/4 extended completely across pronotum, small slightly transverse fovea on each side of middle in anterior 1/2, wide, deep fovea on each side medially near lateral margin, distinct central furrow extended from base to transverse furrow; surface finely rugose, with slightly curved, setabearing carinae, setae decumbent, about 1/2 length of carina; anterior and lateral pronotal margins not bordered, all margins crenulate. Elytra with surface dull, finely microreticulate; all striae strongly raised, convex, carinate, carinae nearly continuous, briefly interrupted adjacent to space between interval punctures; intervals with large, shallow, slightly rectangular punctures ( Fig. 17C ). Metasternum long, dull, finely, densely microreticulate, median surface without ridges, laterally with scattered, straight ridges in basal 2/3, median area flat, with median carina extended anteriorly from apical keel 1/2 or more distance to mesocoxae ( Fig. 17D ); metasternal groove not visible or indistinctly so. Lateral protibial teeth unevenly spaced, basal 2 teeth closer together. Mesotibia with 4 spines laterally, spinal bases widely separated, tibia slightly projecting at apex ( Fig. 17D ). Posterior metatrochanteral margin without small teeth; posterosuperior surface of metatrochanter with single large tooth near femur ( Fig. 17G ). Metafemoral surface rugose, with widely, evenly spaced, obliquely transverse, small setae-bearing tubercles, width to length ratio 1.0:1.5, without noticeable flange on anterior margin; posterior metafemoral margin angulate next to trochanter; posterosuperior margin with 2 small, widely spaced teeth ( Fig. 17G ). Metatibia broadly triangular, surface entirely microreticulate, with large, irregular, transversely oblique posteromedian lateral projection, an irregular row of small, obliquely transverse tubercles extended from base to posteromedian projection, inner margin smooth, pubescent ( Fig. 17F ). Apical margin of 5th abdominal ventrite weakly rounded. Genitalia long, basal piece about as long as parameres, proximal end curved; median lobe slightly shorter than parameres, tapered from base to apex, narrower at middle than a paramere, slightly curved upward in apical 1/3, apex angulate in ventral view; parameres slightly curved before apex in lateral view, margin straight, apex narrowly rounded ( Fig. 17E ).

Female. Apical margin of 5th ventrite strongly rounded.

Variation. Length 2.6 to 3.2 mm, width 1.6 to 1.8 mm. Metasternal groove may be more apparent on some specimens; lateral mesotibial spine number varies from 4 to 5, with occasional specimens having 6 spines; number of teeth on posterosuperior metafemoral surface varies from 1 to 2, occasionally a specimen has a third tiny tooth; number of median, obliquely transverse tubercles on metatibia is variable, both shape and size of posteromedian lateral projection vary considerably.

Type locality. of inducta , southwestern Texas ; of knausi , Kansas, Medora; of cartwrighti , New Mexico, White Sands.

Type depository. of inducta, MCZ ; of knausi, CNIC ; of cartwrighti, USNM.

Temporal distribution. May-July.

Geographical distribution. MEXICO. Sonora: vicinity of La Salina Ba. San Jorge ; 24 mi. S. Sonoita. UNITED STATES. Arizona: Cochise Co, 4 mi. S. Wilcox ; Wilcox Playa; 5.8 km E Willcox, Blue Sky Road. Colorado: Bent Co., Hasty . Kansas: Reno Co., Medora . Indiana: Porter Co., Dunes Beach . Illinois: Mason Co., Sand Ridge State Forest . Michigan: Warren Dunes St. Pk . Nebraska: Greeley Co., 10 mi. N. Greeley, sandhills, Jct. hwys 281 & 91 ; Thomas Co., Halsey, Dismal River . New Mexico: Chaves Co., Mescalero Sands ; 15.5 mi. E. Roswell; 9.5 mi W Caprock ; Dona Ana Co., Las Cruces ; Eddy Co., Carlsbad ; Eddy Co., 26 mi. N Carlsbad ; Lea Co., 5 mi. E Loco Hills ; Hidalgo Co., 6 mi. E. Cloverdale ; Lea Co., 4 mi. S Jal ; Otero Co., 24 km S. Alamagordo ; White Sands; Torrance Co., Town of Gran Quivira , 6500 '. Oklahoma: Jackson Co., Jct. Hwy. 6 & Red River ; Marshall Co., Lake Texoma . South Dakota: Bennett Co., Martin ; Fall River Co., Angostura Dam, S. Hot Springs ; Hyde Co., Highmore . Texas: Anderson Co., Tennessee Colony ; Salmon; Andrews Co., Dunes, 1.3 E of Jct. Tx. 115 & FR 181 ; 10 mi. N. Andrews; Bexar Co., S. of San Antonio, Applewhite Rd ; Jct. I-37 & hwy. 1604, Waterwood estates; Brazos Co., College Station ; Brooks Co., 8 mi. S. Falfurrias ; Caldwell Co., 5.5 mi. E Luling ; Cameron Co., Boca Chica Beach ; Crane Co., Jct. 1053 & 1233 ; Culberson Co., Guadelupe Mts. National Park ; El Paso Co., Anthony ; Horizon City; Johnson Co., Cleburne St. Park ; Lamb Co., Littlefield ; Lee Co., Fedor ; Leon Co., 5 mi. N Flynn ; 9 km N. Flynn ; Martin Co., Stanton ; Milam Co., 5.6 km NE Gause ; Ward Co., Monahans Dunes ; Winkler Co., 10 mi. NE Kermit ; Winkler Co., 20 mi. NE Kermit ;. 5 mi. NE VIC, Jct. Hwy 115 & Fm. Rd. 874 . Wisconsin: Wood Co., Griffith State Nursery . Wyoming: Niobrara Co., Lusk ( BYUC) ( CASC) ( CMNC) ( CMNH) ( CNIC) ( CSCA) ( DCCC) ( FSCA) ( JCIC) ( KUNHM) ( RAAC) ( RCCC) ( TAMU) ( UCRC) ( USNM) .

Remarks. A diagnosis for G. inducta would be: average size small, length 2.60 to 3.20 mm; head with vertex and posterior portion of frons dull, densely, finely rugose; body short, stout, lateral elytral margins rounded medially; elytral striae raised, strongly carinate, carinae nearly continuous, metatibial surface with armature reduced, median row of tubercles weak, obliquely transverse; posterolateral mesotibial emargination with 4 or 5 spines, spinal bases widely separated.

The most critical character listed above is number of mesotibial spines that nearly always number 4 or 5, but number 6 or more about 2% of the time. If the mesotibial spination and densely rugose vertex characters are applied rigorously, G. inducta can be accurately defined. The metatibial surface armature is useful only in distinguishing G. inducta from G. sabulosa and G. canadensis , not from most other similar species. Of the other species, G. warneri has the same mesotibial spination as G. inducta , but is distinguished by elytral striae weakly raised, and strial carinae broken into distinct segments.

Glaresis canadensis and G. inducta are similar, but G. canadensis is nearly always distinguished by larger average size, length 3.30 to 4.30 mm; posterior portion of frons with pronounced, elongate reticulation; strong metatibial surface armature composed of more or less vertical tubercles; and 6 or more posterolateral mesotibial spines. However, very small G. canadensis specimens occasionally occur, and these small specimens usually have less pronounced metatibial armature. In these instances, if the large G. inducta specimens have 6 or more posterolateral mesotibial spines, identification becomes difficult. Fortunately these instances are rarely encountered.

A series of G. inducta -like specimens collected in Texas, “Bexar Co., Jct. I-37 & Hwy. 1604,” mostly agree with the above diagnosis, but the head sculpture is different enough to create doubt as to correct identification. Because we find no other differences, this series is placed as probably G. inducta . A series of G. inducta was collected at a widely disjunct locality at Wilcox, Arizona, in company with supposed G. canadensis , and again we can find little difference between the Arizona specimens and typical G. inducta . See Remarks under G. canadensis .

Glaresis knausi Brown was synonymized with G. inducta by Gordon (1970); in the same publication Gordon described G. cartwrighti based on two worn specimens from White Sands, New Mexico. With considerably more knowledge of G. inducta distribution and character variation, it is apparent that G. carwrighti must also be considered a junior synonym of G. inducta .

Figures

Figures 17A-17G. Glaresis inducta Horn. A) Habitus view. B) Clypeus and head surface. C) pronotal surface. D) Metasternum and mesotibia. E) Male genitalia. F) Metaleg, dorsal view. G) Metaleg and trochanter, ventral view.