1	Abdomen with marking pattern; black in background with medial yellow markings either maculae, vittae or fasciae, or abdomen with terga 3-6 yellow (see Figs 1, 2, 4)	other species of Toxomerus
–	Abdomen black, sometimes reddish posteriorly, without clear medial/central yellow markings (Figs 3, 10, 12). Abdominal terga with or without yellow lateral margins, continuously yellow from tergum 2 to tergum 5 or interrupted yellow lateral margins (Figs 5, 17, 19)	2
2	Proepimeron black, yellow macula above procoxa absent (Figs 14, 15); scutum variable	3
–	Proepimeron with yellow macula (Fig. 13); scutum with medial white pollinose vitta broadening on posterior margin forming large pollinose macula anterior to scutellum	sp. 1
3	Scutum all dark [usually only postpronotum yellow] or with lateral yellow vitta interrupted, either between postpronotum and transverse suture or ending at transverse suture (Figs 14, 24, 25)	10
–	Scutum with lateral yellow vitta continuous and extending from postpronotum to scutellum (Figs 16, 18)	4
4	Scutellum entirely yellow, black pilose (Figs 26, 27)	9
–	Scutellum black with lateral and posterior margins yellow (Figs 17, 19), sometimes yellow margins not well differentiated from central disc covered by bronze pollinosity, black and/or yellow pilose	5
5	Wing bare basally; costal cell bare on basal half or more, cells CuP, BM and R partly bare (Fig. 6)	7
–	Wing entirely microtrichose, slightly brownish (Borges and Couri 2009: 14, Fig. 13)	6
6	Scutum and scutellum black pilose. Male genitalia with postanal process very reduced. Females with face yellow medially, dark lateroventrally	sp. 2
–	Scutum and scutellum entirely yellow pilose. Male genitalia with postanal process long, more than half as long as surstylus (Borges and Couri 2009: 21, Fig. 47). Females with yellow face with medial broad black vitta	Toxomerus flaviplurus (Hall)
7	Face yellow with two sublateral black vittae (Figs 20, 21); profemur yellow, mesofemur partly yellow; cell BM bare on basal third and on anterior and posterior margins. Eye with triangular emargination large: approximately the half of eye width in lateral view (Fig. 23)	8
–	Face yellow; pro- and mesofemora mostly black, yellow very basally and apically; cell BM microtrichose on apical 1/4 with microtrichia extending more basally on posterior margin. Eye with triangular emargination small: at most a third of eye width in lateral view (Fig. 22)	Toxomerus hieroglyphicus (Schiner) [dark form]
8	Costal cell entirely bare, at most few microtrichia apically; metafemur black apically, yellow on basal third; occiput with dorsal knob posterior to ocellar triangle pointing posteriorly (Fig. 23) (male unknown)	Toxomerus picudus Mengual sp. n.
–	Costal cell bare basally, microtrichose on apical third; metafemur entirely black, at most the apical edge yellow; occiput rounded posteriorly on dorsal section, without any protuberance (Fig. 19) (male unknown)	Toxomerus hauseri Mengual sp. n.
9	Wing entirely microtrichose; scutum and notopleuron yellow and black pilose	Toxomerus paragrammus (Schiner) [dark form]
–	Wing microtrichose with small bare areas: cells CuP, BM and R bare on anterior margin; scutum and notopleuron entirely yellow pilose	Toxomerus incaicus Sack [dark form]
10	Wing bare basally; cell BM bare on anterobasal third or more, cell R1 bare anterior to RS furcation (Fig. 6)	13
–	Wing almost entirely microtrichose, in some cases only a bare line following vein M on anterior margin of cell BM and on posterior margin of cell R	11
11	Katepisternal yellow macula well developed (Figs 13, 15). Pro- and mesotibiae yellow with subapical or medial brown to black ring, less evident in the protibia; wing hyaline, extensively microtrichose with small bare area on both sides of vein M on the basal portion of cell bm, and costal cell bare very basally; in males, antennal bases yellow dorsally and laterally, medial black facial vitta not surrounding antennal bases; in females, abdomen shiny or matte black with no pollen pattern	12
–	Katepisternal yellow macula absent or greatly reduced (Fig. 14). Pro- and mesotibiae bright yellow; wing slightly infuscated, brownish, entirely microtrichose; in males, medial black facial vitta surrounding antennal bases forming narrow dark area between antennal bases; in females, abdomen with black pollen pattern forming at least a black pollinose fascia on tergum 2 (Fig. 10)	Toxomerus flaviplurus (Hall)
12	Notopleuron yellow; supra-alar area dark and post-alar callus yellow (http://www.eol.org/data_objects/11884429); scutellum black with broad yellow vitta on lateral and apical margins. Male genitalia: postanal process narrower, as long as or a bit longer than basal width (Fig. 28). Female unknown	Toxomerus circumcinctus (Enderlein)
–	Notopleuron black, at most with triangular small yellow macula anteriorly, with a submedial position, not on the most lateral margin (Fig. 15); supra-alar area dark and post-alar callus dark brown; scutellum black basally and laterally, yellow only apically. Male genitalia: postanal process more triangular, broader at the base than long (Fig. 29)	Toxomerus anthrax (Schiner)
13	Metacoxa brown to black; metafemur black, at most basal and apical apices yellowish; abdomen entirely black or with yellow vitta on lateral margins, continuous or briefly interrupted at posterior margins of each tergum or abdomen with terga 3–6 yellowish-red	14
–	Metacoxa yellow; metafemur black, yellow on basal 1/4–1/3; abdomen black with terga 2, 3, 4 and 5 with triangular yellow macula on anterior 1/2–2/3 of lateral margins (Borges and Couri 2009: 217, Figs 22, 23)	Toxomerus basalis (Walker) [dark form]
14	Pro- and mesofemora dark brown to black, at least on basal half, with apical apex yellow; katepisternal yellow macula broad, broader than anepisternal yellow vitta and normally wider than mesofemur (Figs 13, 24, 25); scutum with a different pattern	15
–	Pro- and mesofemora entirely yellow (male unknown); katepisternal yellow macula reduced, as broad as anepisternal yellow vitta, as wide as or narrower than mesofemur (see Fig. 14); scutum with three broad blue-steel pollinose vittae divided by two submedial brown-bronze pollinose vittae (http://www.eol.org/data_objects/11884446)	Toxomerus funestus (Doesburg)
	Note: Some specimens of Toxomerus dispar may have pro- and mesofemora entirely yellow but they also have katepisternal yellow macula broad and usually abdomen mainly yellow or with evident yellow markings (Figs 1, 2, 4).
15	Postpronotum bright yellow (Fig. 24); notopleuron black or yellow. Postanal process of male genitalia variable	16
	Postpronotum dark brown to black (Fig. 25); notopleuron black. Male genitalia with postanal process short, little distinct, much less than half as long as surstylus (Borges and Couri 2009: 22, Fig. 56)	Toxomerus laenas (Walker)
16	Male face entirely yellow; female face with medial black vitta. Notopleuron entirely black. Female abdomen black, shiny or matte, without clear pollinose pattern, sometimes with small yellow areas along lateral margins or lateral margins entirely yellow	17
–	Male and female face with medial black vitta. Notopleuron partly yellow, usually with triangular small yellow macula anteriorly (Fig. 24). Female abdomen usually shiny black with black lateral margins, or terga 4 and 5 with lateral yellow margins; tergum 2 with submedial black pollinose fascia and terga 3 and 4 with four black pollinose vittate maculae (Fig. 9)	Toxomerus nitidus (Schiner)
	Note: Some specimens of Toxomerus dispar may have notopleuron entirely yellow but they also have abdomen mainly yellow or with evident yellow markings (Figs 1, 2, 4).
17	Abdomen partially black on lateral margins: male usually with terga 1 and 2 black, and following terga dark reddish-brown; female usually entirely black (Figs 3, 5). Pro- and mesotibiae yellow. Postanal process of male genitalia long, more than half as long as surstylus (Fig. 8). Females with metaepisternum partly or entirely yellow	Toxomerus dispar (Fabricius) [dark form]
–	Abdomen uniformly black with continuous yellow on lateral margins, from tergum 2 to apex. Pro- and mesotibiae yellow, usually with medial dark ring of variable length. Male genitalia with postanal process short, much less than half as long as surstylus. Females with metaepisternum entirely black	sp. 3