Key to the Encarsia species-groups

1.         Tarsus of middle leg 4-segmented (apical two segments at least partially fused).........2
1b.       Tarsus of middle leg 5-segmented.................................................................................4

2.         Fore wing narrow with marginal fringe longer than width of wing; each side lobe with
            one seta; base of metasoma usually sculptured; F1 of males with round sensorial/
            glandular process in some species; ex. Diaspididae............................ singularis group
                        Species: africana, lilyingae, mohyuddini, singularis
2b.       Fore wing broader with marginal fringe not longer than width of wing; each side lobe
            with 2 or more setae; base of metasoma usually smooth; ex. Aleyrodidae..................3

3.         Fore wing with an asetose area around stigmal vein; F2 of male antenna with round
            sensorial/glandular process..................................................................cubensis group
                        Species: aleurothrixi, cubensis, hamoni, hansoni, interstricta, nigricephala, quaintancei
3b.       Fore wing without an asetose area around stigmal vein; F2 of male antenna without
            round sensorial/glandular process..........................................................luteola group
                      Species: brasiliensis, brunnea, desantisi, formosa, gallardoi, guadeloupae, haitiensis, hispida,
                                            luteola , meritoria, variegata

4.         Fore wing with an asetose area around stigmal vein...................................................5
4b.       Fore wing without an asetose area around stigmal vein..............................................7

5.         Marginal fringe of fore wing longer than width of wing; each side lobe with one seta;
            base of metasoma usually sculptured; ex. Diaspididae............................citrina group
                      Species: agilior, citrina, curtifuniculata, eugeniae?, flava, flavus, fuscus, gracilens, kemneri,
                                           latipennis, lounsburyi, pauliani?
5b.       Marginal fringe of fore wing not longer than width of wing; each side lobe with 2 or
            more setae; base of metasoma usually smooth; ex. Aleyrodidae.................................6

6.         Valvulae III apex truncate.............................................................longifasciata group
                        Species: aleuroplati, arabica, longifasciata
6b.       Valvulae III apex rounded..................................................................parvella group
                      Species: acaudaleyrodis, americana, aseta, basicincta, citrofila?, flavescens, gerlingi,
                                      lanceolata, mineoi, nipponica, parvella, pergandiella, sueloderi, tabacivora, telemachusi

7(6b).   Scutellar sensilla very closely  placed, separated by a distance of about the width of
             one sensillum or less...................strenua group..........................................................8
7b.        Scutellar sensilla widely spaced, separated by a distance of more than the width of
             one sensillum.............................................................................................................15

8(7).   Club 3-segmented; most species entirely yellow or with dark transverse bands on
           metasoma; ex. Aleyrodidae or Diaspididae. .................................................................10
8b.     Club 2-segmented or undifferentiated; most species with metasoma with extensive
          dark markings; ex. Aleyrodidae....................................................................................14

9(8).     Apex of costal cell with exceptionally long setae; stigmal vein separated from marginal
            vein by a distinct constriction; body usually extensively yellow, rarely dark; fore wing hyaline
             ................................................................................................................strenua subgroup
                  Species: abundantia, armata, aureola, bimaculata, citri,  costaricensis, dialeurodis,
                         magnivena, muliyali, neocala, norani, oakeyensis, perpulchella?, perstrenua,
                         protransvena, pulliclava, ramsesi,  sophia, strenua.
9b.      Apex of costal cell without exceptionally long setae; stigmal vein smoothly joining
           marginal vein; fore wing usually with infuscate area under marginal vein.......................11

11(10b).  Metasoma yellow with transverse dark bands; valvulae III often very short;
                male with 5-segmented antennae or with F5 and F6 partially fused........citrella subgroup
                        Species: citrella, paracitrella, pseudocitrella, unicitrella
11b.        Metasoma without transverse bands; valvulae III not exceptionally short;
               male antennae 6-segmented.........................................................................................12

12(11b)    Forewing narrow with marginal fringe longer than 0.5x FWW...........titillata subgroup
                        Species:   chaoi, titillata
12b.          Forewing wider with marginal fringe shorter than 0.4x FWW.................................13

13(12b)     Scutellar placoid sensillae kidney-shaped or elliptical; body entirely yellow or nearly so;
                  ex. Aleyrodidae..................................................................................longivalvula subgroup
                         Species: lehri, longivalvula, macroptera, vanharteni.
13b.           Scutellar placoid sensillae round; metasoma dark brown; ex. Diaspididae.......bella subgroup
                          Species:  affectada, bella koebelei

14(8b).     Apex of costal cell with exceptionally long seta; F1 cylindrical, at least 1.5x as long as wide;
                 setae; antennae often with scape and/or club segments dark and infuscate forewing
                 ......................................................................................................................japonica subgroup
                    Species:  aurithorax?,brevivena, catherinae, japonica, lycopersici,  persequens, primitiva, quercicola,
                            semigriclava, sinica, ustulata
14b.          Apex of costal cell without exceptionally long setae; F1 quadrate or nearly so; distinctly
                 shorter than F2; antennae without dark segments; fore wing hyaline..............divergens subgroup
                  Species: divergens, phaea, portoricensis

15(7b).      Ovipositor longer than mid tibia and basitarsus combined and valvulae III longer or
                  only slightly shorter than 0.5 valifer II ; metasomal tergite VII usually elongate and
                  conical, as long as, or longer than wide.....................................................................16
15b.           Ovipositor shorter than mid tibia and basitarsus combined; if as long as or
                  longer, then either vavlvulae III apparently shorter than 0.5 valifer II or metasomal
                  tergite VII not conical and elongate, its basal width longer than its median length....17

16(15).     F1 transverse, quadrate to slightly longer than wide; F2 often longer than F3; males
                with F1 and F2 usually expanded..........................................................opulenta group
                  Species: amicula, bangalorensis, bellottii, circumsculpturata, clypealis, coimbatorensis,  dominicana,
                               eurystoma, fujianensis, ishii, longicauda, nigriventris?, opulenta, perbella?,  perplexa, phaea?
16b.          F1 cylindrical, distinctly longer than wide; F2 rarely longer than F3; males of
                 known species with F1 and F2 not expanded..................................albiscutellum group
                  Species: albiscutellum, albiscutellum longipalpa, nigrifemur, socratis

17(15b)   Setae along anterior margin of margin vein very short, as long as, or shorter than width
                of marginal vein; ex. Diaspididae................................................................tristis group
                      Species: tristis
17b.         Setae along marginal vein not shorter than width of marginal vein...............................18

18(17b).   Mouth fossa clearly broader than 0.5X frontovertex width or longer than malar space length;
                 mandible large, with a distinct ventral tooth; F1 and F2 short and quadrate; antennal
                segments multicolored in known species; ex. Aleyrodidae..............................merceti group
                        Species: bennetti, merceti
18b.         Mouth fossa not broader than 0.5X frontovertex width and not longer than malar space
                length; mandible not enlarged, ventral tooth not distinct...................................................19

19(18b)   Fore wing narrow, about 3X as long as wide; marginal fringe at least 0.6X max. forewing
                disk width (FWW); basitarsus II short, less than or equal to 2X proximal tarsal segment,
                with mid tibial spur approximately as long as basitarsus II; midlobe usually with 2-3 pairs
                of setae; scutellar placoid sensilla widely separated; body often with midlobe and
                scutellum yellow and metasoma partially or completely dark brown ex. Diaspididae
                ................................................................................................................inquirenda group
                       Species: aonidiae, diaspidicola, explorata, fasciata, flexa?, inquirenda, inserens, insulana, leucaspidis,
                              leucippi?, luoae, marginata?, nanjingensis, niigatae, nupta, paradiaspidicola, persea, picta, plana,
                              planchoniae, pseudoaonidiae, sancta, sankarani, taciti, titillata?, tennysoni, unfasciata
19b.         Fore wing width moderate to broad, about 2.5X as long as wide; marginal fringe less than
                0.6X FWW; basitarsus II longer than 2X proximal tarsal segment, with mid tibial spur
                usually shorter than basitarsus II; midlobe usually with more than 3 pairs of setae;
                body color variable.......................................................................................................20

20 (19b)   F2 longer than F3; F1 short, transverse to quadrate; club 3-segmented; ovipositor
                 valvulae III often dark brown; mid tibial spur subequal to basitarsus; male with F5 and
                 F6 partially fused in known species;  F2 expanded or with papillate sensillae in some
                species; ex. Diaspididae..............................................................................aurantii group
                             Species: aurantii, bicolor, brachyura, brimblecombei?, ectophaga, elongata, fuzhouensis, gigas,
                                    intermedia, minuta?, noyesana, obtusiclava, peltata, perniciosi, pura?
20b.        F2 not longer than F3; F1 transverse to cylindrical; club variable; valvulae III
               dark brown or pale; mid tibial spur shorter than basitarsus II; male with F5 and F6 separated
               or partially fused; F2 not expanded, but with papillate sensillae in some species................21

21(20b)     Face with dark transverse bands over toruli; flagellum with dark longitudinal sensillae
                 and distinct, clava 2-segmented with apical segment darker than previous segment;
                 ex. Aleyrodidae..........................................................................................elegans group
                  Species: collecta?, elegans, exornata, exserta, grotei?, iris?, isaaci, microtricha, narayanai,
                         occultans, perniciosi?, tinctoriae?, trivittata
21b.         Face without dark transverse bands over toruli; flagellum longitudinal sensillae not
                dark and distinct, clava 2 or 3-segmented with apical segment not darker than
                previous segment.............................................................................................................22

22(21b)    Antennal club 2-segmented or undifferentiated, segments usually long...........................23
22b.          Antennal club 3-segmented.............................................................................................25

23(22).     F1 and F2 short and subequal; F6 (apical club segment) elongate and tapering to a point; ex.
                 Diaspididae....................................................................................................berlesei group
                   Species: aspidioticola?, berlesei, peruviana, totiaurea?
23b.          F1 and F2 not short and subequal; F6 not as long and tapering; ex. Aleyrodidae.............24

24(23)     Male F3 with at least 2 papillate sensilla; F1 and/or F2 often with specialized sensilla or
                modifications; female body usually extensively yellow and with long, narrow forewing and
                marginal fringe; ex. Aleyrodidae.....................................................................perflava group
                  Species: aethiopica?, aleurochitonis, aleuroilicis, ancistrocera, antiopa?, bothrocera?,
                        cibcensis confusa?, dourunga?, echinocera, elegantula?, hamulata?, justicia?, perflava, pseudococci?,
                        shutovae?, silvestrii?, silvifilia?, synaptocera, viggianii?
24b.        Male F3 without papillate sensilla; F1 and F2 without specialized sensilla or modifications;
               female usually with more dark areas and forewing not as long and narrow; ex. Aleyrodidae
               ......................................................................................................................inaron group
                  Species: accenta, adusta, azimi, brevivalvula, coquilletti, coryli, cybele, duorunga, estrellae, galilea,
                          gunturensis, inaron , ixorae?, lauta, lipaleyrodis?, longicornis, lopezi, margaritiventris, maritima?,
                         moffsi?, multiciliata?, reticulata, siphonini, socratis?, thoreauini?, trjapitzini?, whittieri?

25(23b).      Valvulae III dark brown in contrast to valvifer II; male F2 often swollen....................26
25b.             Valvulae III light, similar to color of valvifer II; male F2 not swollen.........................27

26(25).        F1 transverse, rarely quadrate; axilla seta located apically; forewing narrow; body
                    delicate, mostly light colored; male with F2 antennal segment swollen but without
                    papillate sensillae; ex. Aleyrodidae...............................................................lutea group
                      Species: abatei, asterobemisiae, davidi, dialeuroporae, hamata, indica, lutea , marinikia?,
                                metsheryakovi?, udaipuriensis
26b.             F1 slightly longer than wide; axilla seta located centrally; forewing broad, body usually
                    dark with scutellum light; male with F2 antennal segment with papillate sensillae;
                    ex. Hormaphidinae (Aphididae) and Aleyrodidae...............................flavoscutellum group
                      Species: ex. Aphididae: cerataphivora, flavoscutellum, noordami, thoracaphis; ex. Aleyrodidae - aleurotubae, olivinae

27(25b)    Body entirely yellow to orange or with slight infuscate areas or bands; ex.
                 Aleyrodidae...................................................................................................................28
27b.          Body often with dark mesoscutum and gaster and light scutellum .................................30
 

28(27)      F1, F2 and F3 subequal, slightly longer than wide; mid tibial spur elongate...tremblayi group
                  Species. aleuroilicis, pura, tremblayi
28b.         F1 not subequal and slightly longer than wide, usually much wider than long; mid
                tibial spur short or long..................................................................................................29

29(28b).   Male aedeagus short and broad; midtibial spur about 0.5x basitarsus; F1 and F2
                 about 1.5x as long as wide ex. Aleyrodidae....................................................porteri group
                    Species: neoporteri, porteri
29b.          Male aedeagus normal, i.e. elongate and narrow; midtibial spur subequal to basitarsus;
                 F1 and F2 very long, more than 2x as long as wide; ex. Aleyrodidae.........lahorensis group
                    Species: lahorensis, ?maria, ?praegandis,

30(27b)   F1 quadrate to slightly longer than wide, distinctly shorter (about 0.5x) than F2,
                and without a linear sensillum; F5 and F6 not fused; in E. smithi, fore wing
                infuscate under marginal vein..........................................................................smithi group
                      Species: smithi
30b.          F1 cylindrical, with a linear sensillum; all flagellar segments subequal in length;
                 male F5 and F6 partially fused in known species; forewing hyaline or infuscate
                 ..................................................................................................................tricolor group
                  Species: brittanica, dichroa, gautieri, longisetae?, maria?, peltata, scapeata, tricolor

Unplaced Species: ashmeadi, brahmsi, caelibaris, clara, fasciafacies, filicornis, horatii, lasallei, lougae,
marxi, mozarti, orientalis, picithorax, plaumanni, polaszeki, schilleri, septentrionalis,
submetallica, swifti, synaptocera?, toticilia.

The preceding is a preliminary key to the Encarsia species groups. Groups keyed out in the first
six couplets are well defined while those in the latter couplets are not as well defined. I have placed a
question mark (?) after species whose placement in the group is questionable, because they may not
share all of the characters in the group or the species description and/or illustrations do not include
sufficient details of characters needed to place the species in the group. I have divided the strenua group
into subgroups, some of which have been previously designated as separate species groups
(japonica, divergens), species complexes (citrella), and some are new designations (bella, longivalvula, titillata).