1	Hind wing vein SC+R present	2
–	Hind wing vein SC+R absent	42
2(1)	Metasomal terga 3-6 granulate apically, rarely smooth medially but at least granulate laterally	3
–	Metasomal terga 3-6 smooth apically	15
3(2)	Vertex granulate and usually with distinct transverse rugae behind ocelli, occasionally finely striate behind ocelli	4
–	Vertex evenly granulate behind ocelli	6
4(3)	Face granulate; temple in dorsal view narrow, sloping behind, width less than 1/2 eye width	Heterospilus ektorincon Marsh, sp. n.
–	Face rugose; temple in dorsal view broader, not distinctly sloping behind eye, width about 1/2 eye width	5
5(4)	Head dark brown, usually with yellow eye orbits; flagellum brown with white annulus near apex	Heterospilus rojasi Marsh, sp. n.
–	Head entirely brown or dark brown; flagellum entirely brown, without white annulus	Heterospilus austini Marsh, sp. n.
6(4)	Stigma of fore wing yellow or honey yellow	7
–	Stigma of fore wing brown or black, occasionally hyaline brown	9
7(6)	Metasoma mostly yellow or honey yellow, head and mesosoma dark brown or black	Heterospilus flavisoma Marsh, sp. n.
–	Metasoma with at most apical terga 6-7 lighter, remainder of terga dark brown, concolorous with mesosoma	8
8(7)	Scape yellow with lateral longitudinal brown stripe	Heterospilus achi Marsh, sp. n.
–	Scape entirely dark brown or black	Heterospilus dianae Marsh, sp. n.
9(6)	Ovipositor at most as long as metasomal tergum 1, usually shorter	10
–	Ovipositor longer than metasomal tergum 1	12
10(9)	Metasomal tergum 1 distinctly wider at apex than length; flagellum entirely brown with white annulus near tip	Heterospilus cora Marsh, sp. n.
–	Metasomal tergum 1 width equal to or less than length; flagellum with white annulus near tip	11
11(10)	Body entirely black or dark brown	Heterospilus barbalhoae Marsh, sp. n.
–	Head, mesoscutum, metasomal tergum 2 dorsally and apical metasomal terga honey yellow, remainder of body brown	Heterospilus quitirrisi Marsh, sp. n.
12(9)	Metasomal tergum 1 length equal to apical width	13
–	Metasomal tergum 1 length greater than width	14
13(12).	Propodeum in dorsal view with small but distinct tubercles just above hind coxae; flagellum with white annulus near tip	Heterospilus chorotegus Marsh, sp. n.
–	Propodeum without tubercles above hind coxae; flagellum entirely brown, without white annulus	Heterospilus wrightae Marsh, sp. n.
14(12)	Metasomal terga entirely brown	Heterospilus carolinae Marsh, sp. n. (in part)
–	Metasomal terga 5-7 yellow, terga 1-4 brown	Heterospilus zapotec Marsh, sp. n. (in part)
15(2)	Body, including head, flattened dorso-ventrally	Heterospilus complanatus Marsh, sp. n.
–	Body not flattened dorso-ventrally	16
16(15)	Prescutellar furrow with one cross carina	17
–	Prescutellar furrow with 3-5 cross carinae	18
17(16)	Hind coxa brown, fore and mid coxae yellow	Heterospilus phaeocoxus Marsh, sp. n.
–	All coxae unicolorous yellow or light brown	Heterospilus kikapu Marsh, sp. n.
18(16)	Propodeum with median basal carina distinct and long, at least as long as median cross carina of prescutellar furrow, usually longer	19
–	Propodeum with median basal carina absent, if rarely a short carina apparently present, it is shorter than median cross carinae of prescutellar furrow, costulae of areola usually meeting at base of propodeum	24
19(18)	Scape yellow or brown, without lateral longitudinal brown stripe	20
–	Scape yellow, with lateral longitudinal brown stripe	21
20(19)	Fore wing vein r slightly less than 1/2 length of vein 3RSa; flagellum entirely brown; ocell-ocular distance 1.5 times diameter of lateral ocellus	Heterospilus amuzgo Marsh, sp. n.
–	Fore wing vein r nearly as long as vein 3RSa; flagellum brown with apical flagellomeres white; ocell-ocular distance 2.5 times diameter of lateral ocellus	Heterospilus zitaniae Marsh, sp. n.
21(19)	Metasomal tergum 2 yellow or lighter than remainder of terga	Heterospilus bicolor Marsh, sp. n.
–	Metasomal tergum 2 brown, concolorous with remainder of terga	22
22(21)	Mesoscutum light brown or honey yellow	Heterospilus cangrejaensis Marsh, sp. n.
–	Mesoscutum dark brown	23
23(22)	Ovipositor as long as metasomal tergum 1	Heterospilus guapilensis Marsh, sp. n.
–	Ovipositor 3/4 length of metasoma	Heterospilus chocho Marsh, sp. n.
24(18)	Face smooth	25
–	Face sculptured, striate, granulate or areolate	26
25(24)	Scutellum smooth	Heterospilus pitillaensis Marsh, sp. n.
–	Scutellum granulate	Heterospilus orosi Marsh, sp. n.
26(24)	Notauli meeting posteriorly in triangular rugose area	27
–	Notauli meeting posteriorly in triangular costate or costate rugose area	32
27(26)	Basal median areas of propodeum distinctly margined	Heterospilus cocopa Marsh, sp. n.
–	Basal median areas of propodeum not margined, often small or absent	28
28(27)	Ocell-ocular distance 2.5-3 times diameter of lateral ocellus	29
–	Ocell-ocular distance 2 times or less diameter of lateral ocellus	30
29(28)	Fore wing vein r usually as long as, or rarely very slightly shorter than, vein 3RSa	Heterospilus jonmarshi Marsh, sp. n.
–	Fore wing vein r distinctly shorter than vein 3RSa	Heterospilus ixcatec Marsh, sp. n.
30(28)	Propodeum with distinct tubercle or projection apico-laterally just above hind coxae	Heterospilus sumo Marsh, sp. n.
–	Propodeum without tubercle or projection above hind coxae	31
31(30)	Legs bicolored, hind femur yellow on basal half, brown on apical half; flagellum brown with white annulus near apex	Heterospilus villegasi Marsh, sp. n.
–	Legs entirely yellow; flagellum entirely brown	Heterospilus nemestrinus Marsh, sp. n.
32(26)	Basal median areas of propodeum not distinctly margined	33
–	Basal median areas of propodeum distinctly margined	34
33(32)	Body light brown to honey yellow; flagellum entirely brown	Heterospilus achterbergi Marsh, sp. n.
–	Head and mesosoma dark brown, metasoma bicolored dark brown and yellow; flagellum brown with weak apical white annulus	Heterospilus pech Marsh, sp. n.
34(32)	Vertex with more or less distinct transverse rugae or costae behind ocelli	35
–	Vertex entirely granulate	38
35(34)	Scape entirely brown or dark brown	Heterospilus sharkeyi Marsh, sp. n.
–	Scape yellow with lateral longitudinal brown stripe	36
36(35)	Head yellow	Heterospilus ugaldei Marsh, sp. n.
–	Head dark brown	37
37(36)	Mesoscutal lobes brown to light brown, lighter than remainder of mesosoma	Heterospilus jennieae Marsh, sp. n. (in part)
–	Mesosoma entirely dark brown	Heterospilus arawak Marsh, sp. n.
38(34)	Scape brown or dark brown	39
–	Scape yellow with lateral longitudinal brown stripe	40
39(38)	Stigma yellow	Heterospilus puertoviejoensis Marsh, sp. n.
–	Stigma brown	Heterospilus chilamatensis Marsh, sp. n.
40(38)	Apical metasomal terga dark brown, concolorous with anterior terga	Heterospilus carolinae Marsh, sp. n. (in part)
–	Apical metasomal terga yellow, remainder of terga dark brown, tergum 2 often with yellow spots laterally	41
41(40)	Metasomal tergum 2 entirely dark brown	Heterospilus zapotec Marsh, sp. n. (in part)
–	Metasomal tergum 2 brown with yellow spots laterally	Heterospilus zoque Marsh, sp. n.
42(1)	Metasomal terga 3-6 smooth apically	43
–	Metasomal terga 3-6 granulate apically	60
43(42)	Ovipositor as long as or shorter than metasomal tergum 1	44
–	Ovipositor longer than metasomal tergum 1	51
44(43)	Scape yellow or brown without lateral brown stripe	45
–	Scape yellow with more or less distinct lateral longitudinal brown stripe	46
45(44)	Length of metasomal tergum 1 nearly twice apical width; mesoscutal lobes weakly granulate and shining	Heterospilus nahua Marsh, sp. n.
–	Length of metasomal tergum 1 equal to apical width; mesoscutal lobes distinctly granulate and dull	Heterospilus poqomam Marsh, sp. n.
46(44)	Basal median areas of propodeum distinctly margined	47
–	Basal median area of propodeum not distinctly margined	49
47(46)	Mesoscutal lobes weakly granulate and shining	Heterospilus mam Marsh, sp. n.
–	Mesoscutal lobes distinctly granulate and dull	48
48(47)	Length of metasomal tergum 1 at least 1.5 times apical width, often nearly twice as long	Heterospilus strazanaci Marsh, sp. n.
–	Length of metasomal tergum 1 about equal to apical width	Heterospilus aubreyae Marsh, sp. n.
49(46)	Propodeum with distinct tubercle (raised carina) laterally just above hind coxa	Heterospilus vulcanus Marsh, sp. n.
–	Propodeum without distinct tubercle laterally above hind coxa	50
50(49)	Prescutellar furrow with 3 cross carinae; mesoscutal lobes weakly granulate and shining	Heterospilus jabillosensis Marsh, sp. n.
–	Prescutellar furrow with 1 cross carina; mesoscutal lobes distinctly granulate and dull	Heterospilus parkeri Marsh, sp. n.
51(43)	Scape yellow without lateral longitudinal brown stripe; flagellum entirely brown	52
–	Scape yellow with lateral longitudinal brown stripe; flagellum with apical white annulus	54
52(51)	Fore wing vein r at most half as long as vein 3RSa	Heterospilus ixil Marsh, sp. n.
–	Fore wing vein r nearly as long as or equal to vein 3RSa	53
53(52)	Body entirely yellow or honey yellow	Heterospilus warreni Marsh, sp. n.
–	Body entirely dark brown	Heterospilus longisulcus Marsh, sp. n.
54(51)	Areola on propodeum with numerous distinct cross carinae or costae	Heterospilus tzutujil Marsh, sp. n.
–	Areola on propodeum rugose or areolate-rugose	55
55(54)	Mesosoma entirely dark brown or black	56
–	Mesosoma light brown or bicolored, at least mesoscutum partially light brown or yellow	58
56(55)	Vertex granulate with weak but distinctive transverse rugae behind ocelli	Heterospilus sergeyi Marsh, sp. n.
–	Vertex entirely granulate	57
57(56)	Metasomal tergum 2 dark brown, light brown or honey yellow medially; ocell-ocular distance usually more than twice diameter of lateral ocellus	Heterospilus bennetti Marsh, sp. n.
–	Metasomal tergum 2 entirely dark brown; ocell-ocular distance usually twice or less diameter of lateral ocellus	Heterospilus spiloheterus Marsh, sp. n.
58(55)	Notauli meeting at prescutellar furrow in unsculptured area	Heterospilus lasalturus Marsh, sp. n.
–	Notauli meeting at prescutellar furrow in small triangular costate area	59
59(58)	Temple in dorsal view strongly sloping behind eye	Heterospilus robbieae Marsh, sp. n.
–	Temple somewhat bulging, not strongly sloping behind eye	Heterospilus mopanmaya Marsh, sp. n.
60(42)	Ovipositor as long as or shorter than metasomal tergum 1	61
–	Ovipositor longer than metasomal tergum 1	72
61(60)	Metasomal tergum 2 bicolored brown or dark brown with median yellow or honey yellow spot	62
–	Metasomal tergum brown or yellow, concolorous with anterior and/or posterior terga	67
62(61)	Mesoscutal lobes lighter in color than remainder of mesosoma	Heterospilus tricolor Marsh, sp. n.
–	Mesosoma entirely brown, dark brown or black	63
63(62)	Face smooth, rarely partially very weakly granulate	64
–	Face granulate or striate	65
64(63)	Length of metasomal tergum 1 greater than apical width	Heterospilus saminae Marsh, sp. n. (in part)
–	Length of metasomal tergum 1 equal to apical width	Heterospilus dani Marsh, sp. n.
65(63)	Mesoscutal lobes weakly granulate, shining	Heterospilus aesculapius Marsh, sp. n.
–	Mesoscutal lobes distinctly granulate, dull	66
66(65)	Propodeum with distinct tubercle laterally just above hind coxa	Heterospilus sabrinae Marsh, sp. n. (in part)
–	Propodeum without lateral tubercle above hind coxa	Heterospilus bacchus Marsh, sp. n.
67(61)	Notauli weak or absent posteriorly	Heterospilus caritus Marsh, sp. n.
–	Notauli complete and distinct posteriorly	68
68(67)	Notauli meeting at prescutellar furrow in broadly rugose area	Heterospilus longinoi Marsh, sp. n.
–	Notauli meeting at prescutellar in costate or unsculptured area	69
69(68)	Face more or less smooth and shining	Heterospilus saminae Marsh, sp. n. (in part)
–	Face granulate and dull	70
70(69)	Apical metasomal terga bright yellow, distinctly contrasting with the dark brown anterior terga	Heterospilus kellieae Marsh, sp. n.
–	Apical metasomal terga usually concolorous with anterior terga, rarely slightly lighter brown	71
71(70)	Notauli deeply scrobiculate anteriorly, meeting at prescutellar furrow in deeply costate-rugose area	Heterospilus agujasensis Marsh, sp. n.
–	Notauli shallow and weakly scrobiculate anteriorly, meeting at prescutellar furrow in weakly costate area	Heterospilus sabrinae Marsh, sp. n. (in part)
72(60)	Body entirely yellow, apical metasomal terga rarely darker	Heterospilus microstigmi Richards
–	Body entirely brown or dark brown	73
73(72)	Ovipositor longer than metasoma; flagellum entirely brown	Heterospilus richardsi Marsh & Mello
–	Ovipositor shorter than metasoma; flagellum brown with apical white annulus	74
74(73)	Metasomal tergum 2 entirely brown or dark brown	75
–	Metasomal tergum 2 bicolored brown with yellow area medially	76
75(74)	Mesoscutal lobes weakly granulate, shining	Heterospilus lenca Marsh, sp. n.
–	Mesoscutal lobes granulate and dull	Heterospilus rama Marsh, sp. n.
76(74)	Scape yellow without lateral longitudinal brown stripe	Heterospilus braeti Marsh, sp. n.
–	Scape yellow with distinct lateral longitudinal brown stripe	77
77(76)	Vertex granulate with weak transverse striae or rugae behind ocelli	Heterospilus leenderti Marsh, sp. n.
–	Vertex entirely granulate	78
78(77)	Mesosoma entirely dark brown, concolorous with head	Heterospilus phytorius Marsh, sp. n.
–	Mesosoma partially or entirely brown or light brown or bicolored, usually lighter in color than head	Heterospilus xinca Marsh, sp. n.