Castolus, Stal, 1858

Forero, Dimitri & Mejía-Soto, Andrés, 2021, A striking sexually dimorphic new species of Castolus (Hemiptera: Heteroptera Reduviidae) from Colombia, with new records from Neotropical countries and taxonomic notes on the genus, Zootaxa 5048 (4), pp. 538-560 : 540-541

Key to the species of Castolus (based on Maldonado, 1976)

1 Humeral angle of pronotum with a long spine.............................................................. 2

1’ Humeral angle of pronotum either unarmed, shortly produced, or with a very short tooth, but never with a long spine..... 6

2 Head black, or red-orange with area around ocelli and most of anteocular region black; anterior pronotal lobe black or orange; legs black; hemelytron of a single color with no markings..................................................... 3

2’ Head yellowish, with area around ocelli black; anterior pronotal lobe pale yellow; legs yellowish with dark markings; hemelytron not entirely yellow, usually basally with dark areas...................................................... 4

3 Anterior pronotal lobe black; posterior pronotal lobe on anterior half black with a yellowish orange broad longitudinal marking, posterior half yellowish orange; humeral spine yellowish orange........................ C. nigriventris Breddin, 1904

3’ Anterior pronotal lobe orange or red; posterior pronotal lobe entirely orange (male) or mostly black with posterior half reddish with a W-like pattern (female); humeral spine black............................................ C. rafaeli sp. nov.

4 Femora with an apical and a subapical dark ring, and fine longitudinal dark lines on basal half; anterior pronotal lobe with anterior and posterior margin black, posterior pronotal lobe mostly orange; hemelytron basally pale or with a small dark area............................................................................ C. lineatus Maldonado, 1976

4’ Femora pale yellow with only an apical dark ring; anterior pronotal lobe either entirely yellow or only with the posterior margin black; hemelytron basally with a large dark area, as long as the scutellum........................................ 5

5 Anterior pronotal lobe entirely pale yellow, posterior pronotal lobe pale yellow............. C. pallidus Maldonado, 1976

5’ Anterior pronotal lobe with posterior margin black, posterior pronotal lobe with anterior half orange................................................................................................. C. bolivari Brailovsky, 1982

6 Humeral angle of pronotum with a short tooth.............................................................. 7

6’ Humeral angle of pronotum unarmed or slightly subangularly dilated............................................ 9

7 Ocelli small, slightly elevated; pronotum pale yellow and whitish, posterior lobe with three black spots................................................................................................. C. trinotatus (Stål, 1866)

7’ Ocelli large, elevated; pronotum brown or reddish brown with dark brown areas................................... 8

8 Anterior pronotal lobe pale brown usually with dark areas on disk; posterior pronotal lobe with lateral margin dark brown; antennal scape pale brown to brown.................................................... C. ferox (Banks, 1910)

8’ Anterior pronotal lobe entirely black; posterior pronotal lobe with lateral margin reddish brown; antennal scape black..................................................................................... C. omega Swanson, 2018

9 Anterior and posterior lobes of pronotum concolorous, reddish brown or dark brown; head reddish or brown........... 10

9’ Anterior lobe of pronotum much lighter than posterior, posterior with extensive black or brown area; head black, yellowish or reddish............................................................................................ 11

10 Pronotum dark brown to black, posterior lobe of pronotum with lateral and posterior margins red; scutellum bright red, disc black; clavus and corium dark brown to black; hind margin of pronotum straight; humeral angles rounded....................................................................................... C. rufomarginatus Champion, 1899

10’ Pronotum reddish brown; scutellum brownish; clavus and corium dark red; hind margin of pronotum slightly concave; humeral angles slightly emarginated........................................................ C. spissicornis (Stål, 1860)

11 Head black......................................................................................... 12

11’ Head reddish, if ocellar area black at least neck yellowish.................................................... 13

12 Posterior pronotal lobe with dark brown area on disc not reaching lateral margins; forewing with clavus dark brown, corium whitish with a central ovoid dark spot, area posterior to quadrate cell dark brown.............. C. multicinctus Stål, 1872

12’ Posterior pronotal lobe with brown area reaching lateral margins; forewing with clavus and corium yellowish white, both basally brown, corium apically brown................................................ C. fuscoapicatus (Stål, 1860)

13 Head and legs reddish; posterior lobe of pronotum with pale area yellow or white; forewing with clavus and most of corium whitish, corium sometimes yellow, apically black, rarely as a mostly longitudinal black area.... C. plagiaticollis Stål, 1858

13’ Head yellowish, with black ocellar area, sometimes vertex black; fore and midlegs brownish; forewing with clavus and corium basally yellow up to level of scutellum, black between scutellum and middle of quadrate cell, remaining of corium red.................................................................................... C. tricolor Champion, 1899