Coreidae

Swanson, Daniel R., Taylor, Steven J. & Heads, Sam W., 2017, Nine true bugs (Heteroptera) newly-discovered in Illinois, Zootaxa 4269 (4), pp. 571-585 : 578-579

Key to the Coreidae of Illinois

1 Apex of metatibia ending in short projecting spine ( Meropachyinae ); metafemur strongly arcuate and clavate ( Merocorini )..................................................................................... Merocoris distinctus

- Apex of metatibia without projecting spine; metafemur not strongly arcuate and clavate, although may be incrassate..... 2

2 (1') Anteocular region lacking median sulcus; tibiae not sulcate on outer surface ( Pseudophloeinae ); antennae, head, and pronotum beset with small seta-bearing granules..................................................... Coriomeris humilis

- Anteocular region with median sulcus; tibiae usually sulcate on outer surface ( Coreinae ); dorsum devoid of small seta-bearing granules........................................................................................... 3

3 (2') Metatibiae of both sexes dilated on one or both sides to form a thin foliaceous flange.............................. 4

- Metatibiae of both sexes simple, terete.................................................................. 11

4 (3) Head deflexed, only slightly prolonged beyond antennal bases; tylus compressed and projected upward between antenniferous tubercles as a triangular spine; scape at least 1.5 times longer than head ( Acanthocephalini : Acanthocephala )........... 5

- Head porrect, much prolonged beyond antennal bases; tylus compressed but deflexed between antenniferous tubercles; scape subequal to length of head ( Anisoscelini : Leptoglossus )...................................................... 7

5 (4) Metatibiae broadly dilated for nearly entire length, ending abruptly near apex................. Acanthocephala declivis

- Metatibiae broadly dilated in basal half only, gradually narrowed from middle to apex............................. 6

6 (5') Metafemora of males strongly incrassate, widest at middle, those of females slightly expanded; metatibial expansion of male more-or-less straight on outer and inner margins; fourth antennomere concolorous with proximal segments to yellowish; third sternite often with darkened area beneath metacoxae.................................... Acanthocephala femorata

- Metafemora of both sexes slightly widened to apex; metatibial expansion of male sinuate on outer margin (only slightly on inner margin); fourth antennomere red to yellow; third sternite without darkened area beneath metacoxae............................................................................................... Acanthocephala terminalis

7 (4') Tylus armed with sharp porrect spine; [rostrum reaching posterior margin of metasternum, not extending onto abdomen; outer dilation of metatibia essentially entire, smoothly convex with few small teeth; corial fascia distinct, zig-zagged].............................................................................................. Leptoglossus clypealis

- Tylus unarmed...................................................................................... 8

8 (7') Rostrum only reaching to middle of metasternum, not extending onto abdomen; [outer dilation of metatibia distinctly scalloped; corial fascia distinct, straight]................................................... Leptoglossus phyllopus

- Rostrum extending well onto abdomen................................................................... 9

9 (8') Outer dilation of metatibia distinctly scalloped; corial fascia reduced to one or two small spots on vein................................................................................................... Leptoglossus oppositus

- Outer dilation of metatibia entire, smoothly convex; corial fascia present, zig-zagged, although sometimes faint or absent.. 10

10 (9') Outer dilation of metatibia distinctly longer inner dilation; corial fascia confined to veins; posterior margin of pygophore with median V-shaped notch.............................................................. Leptoglossus corculus

- Outer dilation of metatibia subequal to inner dilation; corial fascia extending beyond veins, although sometimes faint or absent; posterior margin of pygophore with median subrectangular notch.................... Leptoglossus occidentalis

11 (3') Head as long or nearly as long as pronotum; tylus distinctly narrowed and prolonged beyond antennal bases; femora armed beneath; rostrum long, extending to metacoxae; second and third antennal segment triquetrous ( Chelinideini : Chelinidea )........................................................................................ Chelinidea vittiger

- Head not over two-thirds the length of the pronotum; tylus only slightly prolonged beyond antennal bases; rostrum shorter, extending at most to mesocoxae; second and third antennal segment subcylindrical, not triquetrous.................. 12

12 (11') Metafemur armed beneath with many teeth, strongly swollen in the males...................................... 13

- Metafemur unarmed beneath or armed with only 2–3 small teeth, not swollen in either sex......................... 14

13 (12) Ocellar tubercle large; metathoracic scent gland auricle with single disc; antenniferous tubercles armed laterally ( Acanthocerini ) male with metatibia more or less straight.............................................. Euthochtha galeator

- Ocellar tubercle small; metathoracic scent gland auricle with pair of divergent discs; antenniferous tubercle unarmed (Nematopini); male with metatibia strongly bent................................................. Piezogaster alternatus

14 (12') Third antennomere dilated and compressed on both sides, others terete; antenniferous tubercles very prominent; tylus strongly and abruptly deflexed, the space between the tubercles unfilled ( Chariesterini )................. Chariesterus antennator

- All antennomeres terete; antenniferous tubercles not prominent; tylus not strongly deflexed, the space between the tubercles filled ( Coreini )..................................................................................... 15

15 (14') Eyes distinctly projecting beyond apical angle of pronotum; ocelli separated by nearly twice the distance between them and eyes; abdominal spiracles closer to lateral margins than to anterior or posterior margins............. Catorhintha mendica

- Eyes not or slightly projecting to apical angle of pronotum; ocelli separated by distance equal to distance between them and eyes; spiracles equidistant from lateral, anterior, and posterior margins of ventrite ( Anasa )......................... 16

16 (15') Head with long spines near base of antennae; [scape with large black spots; humeral angles obtusely rounded; posterior pronotal margin with triangular projections small but apparent]........................................ Anasa armigera

- Head unarmed..................................................................................... 17

17 (16') Scape bicolorous, longitudinally striped fuscous and testaceous, second and third antennomere mostly fuscous, fourth antennomere contrastingly pale; posterior pronotal margin with triangular projections essentially obsolete; legs mostly pale with conspicuous black spots.................................................................... Anasa repetita

- Antennae more-or-less entirely fuscous, occasionally reddish near apex; posterior pronotal margin with distinct triangular projections; legs peppered but appearing mostly fuscous............................................... Anasa tristis