1	A. Body length (not including appendages) less than 3 mm	2
–	B. Body length more than 3 mm	7
2(1)	A. Metasoma with sclerotized carapace formed by terga 1–3; Chile	Gondwanocentrus
–	B. Metasoma with sclerotized carapace formed by terga 1–4. Widespread	3
–	C. Metasoma lacking sclerotized carapace; five or more sclerotized terga visible in dorsal view; CC. rarely 4th and 5th terga desclerotized but fully exposed; Neotropical	5
3(2)	A. r-m crossvein of forewing present (though often weak), closing second submarginal cell	Stiropius
–	B. r-m crossvein of forewing absent, second submarginal cell of forewing not closed apically	4
4(3)	A. Malar space (distance between base of mandible and eye) relatively short and malar suture present between eye and mandible; Neotropical	Choreborogas
–	B. Malar space relatively long and malar suture absent; Nearctic	Polystenidea
5(2)	A. Second submarginal cell of forewing present; apical abscissa of forewing vein M relatively straight	6
–	B. Second submarginal cell of forewing absent; apical abscissa of forewing vein M sinuate; Neotropical and recently discovered in Papua New Guinea (Braet 2016)	Jannya
6(5)	A. Antenna not emanating from a protruding shelf; eyes emarginate; head wider than long	Bulborogas
–	B. Antenna emanating from a protruding shelf; eyes not emarginate; head at least as long as wide	Conobregma
7(1)	A. Tarsomeres 2‒4 of front and middle legs reduced and compact; tarsomeres 2‒4 each as short as or shorter than wide, 5th tarsomere as long as or longer than tarsomeres 2‒4 combined	8
–	B. Tarsomeres 2‒4 of front and middle legs not reduced and compact; tarsomeres 2‒4 each longer than wide, 5th tarsomere shorter than tarsomeres 2‒4 combined	9
8(7)	A. Hind wing vein R much longer than high and RS weakly curved or absent; widespread.	Yelicones
–	B. Hind wing vein R much higher than long and RS strongly curved; Neotropical	Pseudoyelicones
9(7)	A. Membrane of forewing first submarginal evenly setose; widespread	10
–	B. Membrane of forewing first submarginal with a distinct windowlike patch devoid of setae; Neotropical	Cystomastax
10(9)	A. m-cu crossvein of hind wing long and conspicuous and directed towards base of wing; ovipositor as long as middle tibia or longer	Clinocentrus
–	B. m-cu crossvein of hind wing absent or if present then shorter and not directed towards the base of the wing; ovipositor usually shorter than middle tibia (variable in Triraphis)	11
11(10)	A. 2RS of forewing nearly parallel with r-m, thereby forming a roughly rectangular or subquadrate second submarginal cell	12
–	B. 2RS of forewing angled towards base of wing posteriorly, thereby forming a roughly trapezoidal second submarginal cell	13
12(11)	A. Second submarginal cell of forewing ca. as long as high. AA. Hind trochantellus elongate, 2 or more × longer than trochanter in ventral view; tarsal claws without pectination; Neotropical, rare	Heterogamus
–	B. Lacking one or more of the above characters; most specimens are as follows: second submarginal cell longer than high. BB. Hind trochantellus not elongate, less than 2 × longer than trochanter in ventral view; tarsal claws usually with pectination; widespread, common	Aleiodes (most species, ~90%)
13(11)	A. Hind tibial spurs mostly lacking setae and curved. AA. Hypopygium large; Neotropical, rare	14
–	B. Hind tibial spurs setose and relatively straight. BB. Hypopygium normal; widespread, common	15
14(13)	A. Tarsal claws simple, swollen basally but lacking a distinct lobe. AA. Hind femur swollen apically	Hermosomastax gen. nov.
–	B. Tarsal claws with a squared or slightly acute basal lobe. BB. Hind femur not swollen apically	Bioalfa gen. nov.
15(13)	A. Tarsal claws lacking basal lobe, but often with basal pectin-like row of short spines	Aleiodes (~10% of species)
–	B. Tarsal claws with well-defined sharp tooth or teeth	Triraphis