Belostoma, Latreille, 1807

Key to species of adult Belostoma View in CoL from the four southeastern Brazilian states

( Espírito Santo, Minas Gerais, Rio de Janeiro, and São Paulo)

1 Pilosity (PIL) extending along genital operculum (GOP), covering entire margin of connexivum (CON) ( Fig. 2D View FIGURE 2 ) ...................................................................................................................................................... 2

- Pilosity not extending along genital operculum, or if so, then covering one-third of margin of connexivum ( Fig. 2A–C View FIGURE 2 ).................................................................................................................................................. 6

2 Pilosity covering all or part of sternites ( Fig. 2E View FIGURE 2 ) ....................................................................................... 3

- Pilosity not on sternites ( Fig. 2D View FIGURE 2 )................................................................................................................................................................. B. dilatatum ( Fig. 18B–C View FIGURE 18 ) [ Argentina, Bolivia, Brazil, Paraguay, Uruguay]

3 Inner margin of eye straight; eyes triangular ( Fig. 2I View FIGURE 2 )..................................................................................................................................................................... B. costalimai ( Fig. 17B View FIGURE 17 ) [ Brazil, Colombia, Surinam]

- Inner margin of eye rounded; eyes usually rounded ( Fig. 2J View FIGURE 2 ) ..................................................................... 4

4 Total length (from apex of head to apex of hemelytra at rest) 26.0–34.0 mm ............................................ 5

- Total length not exceeding 21.0 mm......................................................... B. noualhieri ( Fig. 20A View FIGURE 20 ) [ Brazil]

5 Total length about twice greatest width; phallus with outer caudal lateral margins of ventral diverticulum usually sinuous in ventral view ( Fig. 15B–G View FIGURE 15 ) .......................................................................................................................................................... B. testaceopallidum ( Fig. 21B View FIGURE 21 ) [ Argentina, Brazil, Lesser Antilles?]

- Total length more than twice largest width of body; phallus with outer caudal lateral margins of ventral diverticulum convex instead of sinuous in ventral view ( Fig. 14C–H View FIGURE 14 ).......... B. ribeiroi ( Fig. 20C View FIGURE 20 ) [ Brazil]

6 Total length not exceeding 20.0 mm; eyes rounded .................................................................................... 7

- Total length more than 20.0 mm; eyes rounded, subtriangular, or triangular............................................ 11

7 Prosternal keel elevated ( Fig. 11A, E, F View FIGURE 11 ), if not, then projecting anteriorly ( Fig. 11J–K View FIGURE 11 ); greatest pronotal width not twice its median length................................................................................................................ 8

- Prosternal keel not elevated and not projecting anteriorly ( Figs 12A–B; 12F View FIGURE 12 ); greatest pronotal width twice its median length, if not, then B. micantulum .................................................................................. 10

8 Greatest pronotal width only slightly more than twice its median length; dorsal arms of phallotheca always divergent ( Fig. 11L View FIGURE 11 ); ventral diverticulum of phallus slightly cleft apically in ventral view ( Fig. 11M View FIGURE 11 ).......................................................................................................... B. sanctulum ( Fig. 20D View FIGURE 20 ) [ Brazil]

- Greatest pronotal width less than twice its median length; dorsal arms of phallotheca variable; ventral diverticulum of phallus rounded apically, without a cleft in ventral view ( Fig. 11C, H View FIGURE 11 ) ............................ 9

9 Length of segment 1 of rostrum equal to length of segment 2; posterior interocular width more than 1.5 times width of an eye; prosternal keel acute at apex ( Fig. 11A View FIGURE 11 ), not truncated; dorsal arms of phallotheca divergent ( Fig. 11B View FIGURE 11 )............................................... B. candidulum ( Fig. 17A View FIGURE 17 ) [ Argentina, Brazil, Uruguay]

- Length of segment 1 of rostrum only slightly shorter than length of segment 2; posterior interocular width 1.5 times width of an eye; prosternal keel truncated or obtuse at apex ( Fig. 11E–F View FIGURE 11 ); dorsal arms of phallotheca parallel or slightly convergent ( Fig. 11G View FIGURE 11 )...... B. horvathi ( Fig. 19C View FIGURE 19 ) [ Argentina, Brazil, Uruguay] [treated as B. oxyurum by Nieser and Melo (1997) and Ribeiro (1999)]

10 Phallus with ventral diverticulum strongly curved ( Figs 12C–E; 12G–I; 12M–O View FIGURE 12 ) .................................. 11

- Phallus with ventral diverticulum not curved ( Fig. 11D, I, N View FIGURE 11 ) ...................................................................... ............................................................................................... B. orbiculatum [ Argentina, Brazil, Uruguay]

11 Total length 13.5–16.9 mm; phallus with ventral diverticulum usually lacking a medial depression; if present then not distinct ( Fig. 12G–O View FIGURE 12 ); dorsal arms of phallotheca not covering laterodorsal margins of ventral diverticulum ( Fig. 12G, J, M View FIGURE 12 ) ................................................................................................................................................... B. plebejum ( Fig. 20B View FIGURE 20 ) [ Argentina, Brazil, Paraguay, Peru, Uruguay, Venezuela]

- Total length 10.3–13.3 mm; phallus with ventral diverticulum strongly medially depressed ( Fig. 12C–E View FIGURE 12 ); dorsal arms of phallotheca covering the laterodorsal margins of ventral diverticulum ( Fig. 12C View FIGURE 12 )............... B. micantulum ( Fig. 19D View FIGURE 19 ) [ Argentina, Bolivia, Brazil, Colombia, Guyana, Paraguay, Surinam, Uruguay, Venezuela]

12 Inner margin of eye rather straight; eyes triangular ( Fig. 2I View FIGURE 2 ); greatest pronotal width more than twice its median length............................................................................................................................................. 13

- Inner margin of eye convex or sinuous with anterior part convex and posterior part concave; eyes rounded or subtriangular; greatest pronotal width less than twice its median length.............................................. 14

13 Total length usually less than twice largest width of body; anteoculus longer than interoculus; pronotum lacking yellowish or whitish longitudinal stripes ................................................................................................................................. B. bergi ( Fig. 16C View FIGURE 16 ) [ Argentina, Brazil, Chile, México, Paraguay, Peru, Uruguay]

- Total length more than twice largest width of body; anteoculus equal to shorter than interoculus; pronotum with yellowish or whitish longitudinal stripes.............................................................................................................................. B. bosqi ( Fig. 16D View FIGURE 16 ) [ Argentina, Bolivia, Paraguay, Brazil, Peru, Surinam, Venezuela]

14 Total length most often between 22.5 and 27.2 mm; eyes subtriangular with inner margin of eye always convex............................................... B. discretum ( Fig. 18D View FIGURE 18 ) [ Argentina, Bolivia, Brazil, Paraguay, Peru]

- Total length more than 29.4 mm; eyes rounded with inner margin of eye convex or sinuous with anterior part convex and posterior part concave ..................................................................................................... 15

15 Pilosity extending along genital operculum ( Fig. 2B View FIGURE 2 )............................................................................... 16

- Pilosity not extending along genital operculum ........................................................................................ 17

16 Body elongate with its lateral margins slightly parallel; dorsum with peculiar brownish golden hairs (these can drop if handled or not correctly preserved); vertex, pronotum, and posterior part of scutellum with distinct median longitudinal carina............................................................................................................................................ B. aurivillianum ( Fig. 16B View FIGURE 16 ) [ Bolivia, Brazil, Colombia, Paraguay, Surinam, Venezuela]

- Body ovoid and convex; dorsum without pilosity; vertex, pronotum, and posterior part of scutellum without median longitudinal carina.............. B. cummingsi ( Fig. 17C View FIGURE 17 ) [ Argentina, Brazil, Paraguay, Uruguay]

17 Dense covering of short scalelike hairs on body (these can drop if handled or not correctly preserved); vertex, pronotum, and posterior part of scutellum with median longitudinal carina ( Fig. 21A View FIGURE 21 , LOC); scutellum not reaching nodal line (NLI); ventral diverticulum of phallus with ventroapical protuberance not distinct in lateral and ventral views ( Fig. 13C–K View FIGURE 13 )........... B. stollii ( Fig. 21A View FIGURE 21 ) [ Bolivia, Brazil, Guyana, French Guyana, Peru, Surinam, Venezuela]