The Australian species of Encarsia Förster (Hymenoptera, Chalcidoidea: Aphelinidae), parasitoids of whiteflies (Hemiptera, Sternorrhyncha, Aleyrodidae) and armoured scale insects (Hemiptera, Coccoidea: Diaspididae)

The species of Encarsia Förster known from Australia are revised. This study is based mainly on material collected over the last 10 years. Ninety‐four species are recognized, including 38 new species, and seven new records for Australia. All species are fully described or diagnosed, and illustrated by microphotographs. Seven new specific synonymies are proposed and two lectotypes are designated. A key to the females of Australian species of Encarsia is provided. The known hosts and distribution are summarized. The diversity of the Australian Encarsia fauna is discussed.


Introduction
Encarsia Fö rster is a relatively large genus of Aphelinidae, currently containing 283 described species (Noyes 2003). Encarsia species are mostly primary parasitoids of whiteflies (Aleyrodidae) and armoured scale insects (Diaspididae), with four species known from aphids (Hormaphididae) (Evans et al. 1995). Males, however, are commonly hyperparasitoids of females (or males) of their own or other species (reviewed by Walter 1983a, 1983b, Williams and Polaszek 1996, and the males of certain species have been recorded as (probably facultative) hyperparasitoids of Psyllidae (Viggiani 1984;, and obligate parasitoids of lepidopteran eggs (Polaszek 1991;Hunter et al. 1996). Species of Encarsia have been considered as the most efficacious group of biocontrol agents of whitefly pests on a broad range of agricultural crops. Recently their economic importance has been recognized worldwide and more attention has been given to their taxonomy. This is especially true of the Encarsia species parasitic on whiteflies (Huldén 1986;Rivnay and Gerling 1987;Krishnan and Vasantharaj David 1996;Trjapitzin et al. 1996;Schauff et al. 1996;Schmidt et al. 2001). Manzari et al. 2002;Polaszek et al. 2004;Schmidt et al. 2006). This technique has been applied to selected Australian species, for example in the strenua-, inaron-and smithi species groups.

Discussion
Until recently, the Australian Encarsia fauna was largely unknown and the few taxonomic treatments were almost exclusively based on the study of type specimens (e.g. Viggiani 1985c), most of which had been described by Alexandre Arsene Girault (Dahms 1978(Dahms , 1983(Dahms , 1984. After Girault's contribution, the genus Encarsia in Australia was largely ignored, and it was only after the establishment of the B-biotype of the silverleaf whitefly in 1994 that interest in Encarsia resurfaced. Australia has never before had a serious whitefly pest of outdoor crops and, as a consequence, there was very little research experience present in Australia capable of dealing with that pest. Subsequently a research programme was initiated because there were indications that agents capable of contributing significantly to the biological control of this pest may already be present in Australia. Until then only a single species attacking B. tabaci and T. vaporariorum, Encarsia formosa, was known from Australia (Wilson 1960). During this research project it became apparent that the genus Encarsia is particularly diverse in Australia. This observation was supported by the high species richness of host taxa, in particular whiteflies (Carver and Reid 1996;Martin 1999), and the high number of Australian species described by early authors: between 1913 and 1939 44 species of Encarsia were described, mostly by Girault. Nearly all of those species were insufficiently described and they are usually known only from the type specimen which is often in very poor condition. Only a small fraction (eight species) of the species described in the first half of the 20th century were described as Encarsia, the remaining species were originally treated as members of the genera Coccophagus (29 species), Prospaltella (six species), and Aspidiotiphagus (one species).
For Australia we treat 94 Encarsia species as valid, representing about one-third of the known world fauna of the genus. This is the highest number of species for any country, followed by China (76 species;Huang and Polaszek 1998) and India (52 species;Hayat 1998).
Many Encarsia species have a wide or even cosmopolitan distribution, complicating taxonomic revisions on a local scale. However, in Australia three-quarters of the species seem to be restricted in their distribution to Australia, indicating a high level of endemism. At least eight species occurring in Australia have either a wide geographical distribution embracing several major zoogeographical regions (E. aseta, E. azimi, E. bimaculata, E. boswelli, E. brimblecombei, E. dispersa, E. elegans, and E. pergandiella) or are virtually cosmopolitan (E. citrina, E. formosa, E. perniciosi, E. lounsburyi, E. lutea, E. protransvena, and E. sophia).
In Australia species richness of Encarsia is highest in Queensland with 65 species (70%; Table I), followed by Western Australia with 31 species (33%) and New South Wales with 15 species (16%). The remaining states or territories (excluding external territories) have between three (Australian Capital Territory) and nine species (South Australia; Table I).
Despite this high number of species in Australia, we believe that the number of species occurring in Australia is about two to three times higher than currently known. This estimate is to some extent based on the relatively high species diversity of whiteflies in Australia, comprising about 110 described species with estimates of the total number of species being about three times as many (Martin 1999 and personal communication). Furthermore, about one-third of all Encarsia species with known host records parasitize armoured scale insects which are similarly diverse in Australia with about 240 species (Carver et al. 1991). In the present study species attacking armoured scale insects are somewhat underrepresented. This is partly because there has been more interest in parasitoids of whiteflies than in those species attacking diaspidids.

Acronyms for depositories
The following acronyms are used: ANIC, Australian National Insect Collection, Canberra

Diagnosis
For a full generic description of Encarsia and a discussion of morphological characters of Encarsia and closely related genera see Schmidt and Polaszek (2007). The presence of the following character states is required for a positive diagnosis of Encarsia (females): fore and hind tarsi five-segmented; antenna eight-segmented (excluding radicle); scutellum always with two pairs of setae; marginal vein longer than submarginal vein; postmarginal vein absent; stigmal vein very short, always less than one-quarter of the length of the marginal vein. The closely related Coccophagus differs from Encarsia primarily in having six or more setae on the scutellum. However, the generic circumscriptions of the coccophagine genera are currently being reassessed, as are their phylogenetic relationships (P. A. Pedata, A. Polaszek and S. Schmidt, in preparation).
Key to the species of Encarsia (females) from Australia The following key allows the identification of all Encarsia species currently known to occur on the Australian mainland and external territories. The key includes only females because males are known from only about 25% of the species, and in general they are extremely difficult to identify without conspecific females. Descriptions of males are provided where possible to aid identification of males in samples where males and females are present.
Measurements of quantitative characters given in the species descriptions are based on specimens which were available at the time this study was conducted. Additional material or abnormal specimens may reveal values which lie slightly outside the given ranges.
Furthermore, type specimens of species described by Girault are usually in a very poor condition and diagnostic characters are often not visible or distorted. Measurements of Girault species that are only known from the type specimen(s) should be regarded as approximations. We took this into account when creating the key and tried to be as general as possible and as specific as necessary. In cases when a character state is variable, or appears to be intermediate, the species will key out both ways. In critical cases, in particular when a couplet gives only a single character, both ways should be tried and the result should be scrutinized by checking the specimens against the diagnosis and the corresponding illustrations.  95 Metasoma dark, basal two tergites laterally each with three to six (rarely only two) setae. Antennae shorter, F4 about two times as long as its maximum width; F1 less than two times as long as its maximum width ( Figure 12) . . . . E. adusta -Metasoma pale, basal two tergites laterally with zero to two (rarely four) setae. Antennae elongate, F4 distinctly longer than two times its maximum width; F1 at least two times as long as its maximum width ( Figure 48) (0.82-0.88). Flagellomeres with the following numbers of sensilla: F1: 0, F2: 1, F3: 2, F4: 3, F5: 3, F6: 3. Midlobe of mesoscutum with eight setae, arranged symmetrically, side lobes with three setae each. Mesoscutal midlobe, axillae, and scutellum with rather fine but distinctive reticulation, cells with distinct internal striations. Scutellar sensilla widely separated (approximately seven times the maximum width of a sensillum). Distance between anterior pair of scutellar setae greater than between posterior pair. Fore wing 2.4 times as long as width of disc. Marginal fringe 0.26-0.29 times as long as width of disc. Submarginal vein with two setae, marginal vein anteriorly with seven to nine setae. Basal cell with seven or eight setae. Tarsal formula 5-5-5. Apical spur of midtibia distinctly shorter than half the length of the corresponding basitarsus (0.27-0.36). Tergites laterally with the following numbers of setae: T1: 2, T2: 2-3, T3: 2, T4: 2, T5: 3, T6: 3, T7 with four setae. Ovipositor subequal in length to midtibia (0.99-1.04). Third valvula 0.32-0.34 times as long as second valvifer.
Male. Body predominantly brown with mesoscutal midlobe posteriorly and scutellum lighter. Legs light brown except coxae brown, femora, in particular hind femur, lighter brown and tibiae slightly darkened. Apical two segments of antenna fused and sensilla partly overlapping.

Comments
The species is similar to E. thoreauini but has a different wing shape and the setation of the fore wing is more scattered than in the latter species (cf. Figures 16, 285). It also resembles E. aleurochitonis Mercet but can be separated by the reticulate surface sculpture of the stemmaticum, whereas in aferi the sculpture is rugose. Also, aferi has a much longer fore wing marginal fringe which is about 0.2 times as long as the maximum width of disc, whereas in aleurochitonis it is less than 0.1 times. (Girault) (  Chou et al. 1996, p 196;Hayat 1998, p 193. Encarsia albiscutellum (Girault): Polaszek 1998, p 1839.
Host. Aleyrodidae: Aleuroduplidens sp. The following additional host has been recorded : Aleurolobus sp.

Comments
The species is easily recognizable by the combination of long ovipositor, dark brown colour, elongate first funicular segment, and very long midtibial spur.
The type status of E. perbella is unclear. On a slide with a female, labelled ''Coccophagus perbellus'', Girault had crossed out the word ''type'' and replaced it with a ''?''. Therefore Dahms (1986, p 399) did not assign a type number. Encarsia perbella (Girault) is very similar to albiscutellum and shows only minor colour differences of head and mesoscutum. According to Girault's description perbella has, unlike albiscutellum, an orange vertex (except ocellar area) and an orange mesoscutal side lobe with a black spot, legs white except hind coxa. However, since there is no type specimen we are left with Girault's description which is not sufficient to characterize the species sufficiently. The identity of perbella remains unclear until more material of perbella is available that fits Girault's description and for the time being we regard perbella as a junior synonym of albiscutellum.
Male. Similar in colour and morphology to female. Flagellum six-segmented, all segments with abundant sensilla.
Distribution. Australia: Northern Territory, Western Australia.

Male. Unknown.
Species group placement. Not established.

Distribution. Australia: Queensland.
Host. Aleyrodidae: Xenaleyrodes timonii Martin.   The male holotype of Encarsia antiopa (Girault) belongs to the E. perflava group and could be the male of E. justicia. However, the male has a dark infuscation behind the marginal vein which is missing in E. justicia and in the closely related perflava group males E. bothrocera, E. cibcensis, and E. perflava. The male also differs from E. perflava and E. cibcensis by having, similar to E. bothrocera, pit-like sensilla on F1. Unlike E. cibcensis and E. perflava, the male has at least one papillate sensillum on F4. The flagellum of the male holotype of E. antiopa is equipped with the following numbers of pit-like and papillate sensilla: F1 with five to seven pit-like and two papillate sensilla, F2 with about eight papillate sensilla, pit-like sensilla indiscernible, F3 with about seven papillate sensilla and F4 with at least one papillate sensillum.

Male. Unknown.
Species group placement. E. lutea group.

Diagnosis
Female. Colour: body entirely yellow. Fore wing hyaline.

Redescription (holotype)
Female. Colour: head appearing brown. Body yellow. Antenna yellow and legs yellow.

Comments
The type specimen is in very poor condition and apparently has been remounted. Viggiani (1985c, p 235) provides a description of the holotype. However, all wings of the type specimen are missing and hence we cannot confirm the wing characters given by Viggiani. Moreover, the specimen differs considerably from the original description in that the whole body is completely yellow, whereas Girault describes it as similar to E. nigriventris, which has a dark brown gaster. Hence our investigation of the type remains inconclusive and we regard E. ashmeadi as a nomen dubium.

Male. Unknown.
Species group placement. Not established.

Male. Unknown
Species group placement. E. strenua group.

Diagnosis
Female. Colour: head predominantly brown, vertex and area around mouthparts lighter. Mesosoma brown. Metasoma pale yellow to white except with sharply defined narrow dark brown band at base. Antenna yellow with pedicel brown and apical segments slightly darkened. Fore wing hyaline. Legs yellow, coxae and femora slightly darkened.
Male. Body brown with mesoscutal midlobe posteriorly and scutellum lighter. Legs brown, tibiae and tarsi light brown. Apical two segments of antenna fused and sensilla partly overlapping.

Male. Unknown.
Species group placement. Not established.

Diagnosis
Female. Colour: mainly yellow except pronotum, a large anteromedial patch on middle lobe of mesoscutum, axillae, mesopleuron, propodeum, and petiole more or less brown. Head yellow with a transverse brown band. Metasoma mostly yellow except brown at base and occasionally with a faint brown patch on T4 and T5, or tergites more or less brown and petiole, T1, T3, and T4 basally with indistinct transverse brown band. Fore wing hyaline, slightly infuscate near base of marginal vein.
Male. Colour pattern similar to female but darker. Head with a dark transverse band. Apical two segments of flagellum fused.

Comments
Encarsia bimaculata has a distinctive colour pattern that is unique among the species of the E. strenua group, in particular the dark mesosomal colour pattern, although this is sometimes very faint. The other species of the E. strenua group present in Australia are almost completely yellow (E. protransvena, E. oakeyensis, and E. sophia) or predominantly brown (E. ustulata). (Girault) (  67] times as long as its maximum width, subequal in length to F2 and F3. Flagellomeres with the following numbers of sensilla: F1: 2, F2: 2, F3: 2, F4: 3-4, F5: 4-5, F6: 4-5 and with sensory area. F1-F3 cylindrical and similar in shape and size, F4 conical and subequal in length to preapical and apical segment. Midlobe of mesoscutum with about 6-14 setae, side lobes with two to three setae each. Scutellar sensilla separated by approximately five times the maximum width of a sensillum. Distance between anterior pair of scutellar setae smaller than distance between posterior. Fore wing 2.7 times as long as width of disc. Basal cell with two to five setae. Submarginal vein with two setae, marginal vein anteriorly with 7-11 setae. Longest setae of marginal fringe 0.22-0.23 [0.22] times as long as width of disc. Apical spur of midtibia slightly longer than half the length of the corresponding basitarsus (0.59-0.64) [0.64]. Basitarsus of middle leg ventrally with stout setae. Tergites on each side with the following numbers of setae: T1: 0, T2: 1, T3: 1, T4: 1, T5: 2, T6: 2, T7 with four setae. Ovipositor longer than midtibia (1.13-1.23) [1.23] and two times as long as clava. Third valvula about 0.36 times as long as second valvifer.

Encarsia boswelli
Male. No males of the species were collected in the study area. For a description of E. boswelli males from elsewhere see Polaszek and Hayat (1990, p 3).

Comments
Unlike all other known Encarsia species, which have a three-toothed mandible, the mandible of E. boswelli has four teeth. This species is also unusual for an Encarsia because it is an egg parasitoid of black stink bugs (Heteroptera: Plataspidae), and it is the only known obligatory egg parasitoid in the Coccophaginae (Polaszek 1991), except for males of E. porteri which develop in eggs of Lepidoptera (Hunter et al. 1996). The generic placement of E. boswelli has long been debated and it has only recently been placed in Encarsia as part of a revisionary treatment of the Encarsia noyesi species group (formerly Encarsiella) based on molecular and morphological evidence (Schmidt and Polaszek 2007 Morphology: maxillary palp two-segmented. Antennal formula 1,1,3,3. Pedicel longer than F1 (1.3). F1 1.9 times as long as its maximum width, shorter than F2 (0.77) and F3 (0.71). F2 subequal in length to F3. Scutellar sensilla widely separated from each other. Fore wing about 2.5 times as long as width of disc. Marginal fringe 0.18 times as long as width of disc. Basal cell with nine setae. Submarginal vein with two setae, marginal vein anteriorly with nine setae. Tarsal formula 5-5-5. Ovipositor shorter than midtibia (0.87), about 1.2 times as long as clava. Third valvula 0.27 times as long as second valvifer.

Comments
The species can be separated from other members of the strenua group by its relatively short ovipositor.

Male. Unknown.
Species group placement. Not established.

Male. Unknown
Species group placement. Not established.
Host. Aleyrodidae: Aleurocanthus sp. The following additional whitefly host has been recorded Polaszek et al. 1999): Aleurotrachelus micheliae Takahashi. Encarsia citrina has been recorded from a large number of hard scales (Diaspididae, see Huang and Polaszek (1998, p
Morphology: antennal formula 1,1,3,3. Pedicel longer than F1 (1.67). F1 1.4 times as long as its maximum width, slightly shorter than F2 and F3. F2 subequal in length to F3. Midlobe of mesoscutum with eight visible setae. Scutellar sensilla widely separated (approximately seven times the maximum width of a sensillum). Distance between anterior pair of scutellar setae subequal to distance between posterior pair. Fore wing with small bare area near stigmal vein, 2.3 times as long as width of disc. Marginal fringe about 0.3 times as long as width of disc. Basal cell with one seta. Submarginal vein with one seta, marginal vein anteriorly with six setae. Tarsal formula 5-5-5. Apical spur of midtibia subequal in length to corresponding basitarsus. Ovipositor longer than midtibia (1.3) and twice as long as clava. Third valvula about 0.25 times as long as second valvifer.

Male. Unknown.
Species group placement. Not established.

Comments
The species is characterized by the single seta on the submarginal vein in combination with the long midtibial spur and the asetose area in the fore wing near the stigmal vein.

2154
The slide-mounted holotype is in very bad condition and no diagnostic characters are recognizable. The specimen is crushed and wings and antenna are missing. Apparently the specimen has been remounted and the antennae were lost during that process since one antenna was illustrated by Viggiani (1985c, p 239 Girault: Girault 1915[238], p 60 (correction to 1913 description), Dahms 1983, p 207-208, Viggiani 1985c.

Distribution. Australia: New South Wales.
Host. Unknown.

Comments
This species resembles E. smithi but can be separated by the three-segmented clava, fewer setae on the mesoscutum and different wing infuscation.

Diagnosis
Female. Colour: head and mesosoma brown, contrasting with yellow remainder of body. Antenna yellow with petiole and antennal tip slightly darker. Metasoma yellow except brown at base. Fore wing hyaline. Legs pale, coxae more or less brown at base.
Male. Body predominantly brown, legs lighter. Lower half of head, vertex partly and ocellar area brown.

Comments
Encarsia formosa was released into Australia between 1934 and 1936 as a biological control agent of the greenhouse whitefly, Trialeurodes vaporariorum (Wilson 1960
Morphology: maxillary palp two-segmented. Antennal formula 1,1,3,3, F6 appearing conical. Pedicel slightly longer than F1 (1.21). F1 1.56 times as long as its maximum width, subequal in length to F2 and slightly shorter than F3 (0.82). Scutellar sensilla distantly placed. Distance between anterior pair of scutellar setae subequal to distance between posterior pair. Fore wing about 2.5 times as long as width of disc. Marginal fringe 0.34 times as long as width of disc. Basal cell with two setae. Marginal vein anteriorly with six setae. Tarsal formula 5-5-5. Apical spur of midtibia subequal in length to basitarsus. Ovipositor distinctly longer than midtibia (1.55) and 2.41 times as long as clava. Third valvula about 0.3 times as long as second valvifer.

Male. Unknown.
Species group placement. Not established.
Morphology: antennal formula 1,1,3,3. Pedicel slightly longer than F1. F1 slightly shorter than F2 and F3. Only two posterior setae on midlobe of mesoscutum discernible. Scutellar sensilla widely separated (approximately 10 times the maximum width of a sensillum). Distance between anterior pair of scutellar setae greater than between posterior pair. Fore wing about 2.6 times as long as width of disc. Marginal fringe 0.30 times as long as width of disc. Submarginal vein with two setae, marginal vein anteriorly with six setae. Basal cell with three setae. Tarsal formula 5-5-5. Apical spur of midtibia almost as long as the length of the corresponding basitarsus (0.86). T2-4 laterally apparently each with one seta, setation of remaining tergites indiscernible. Ovipositor subequal in length to midtibia, about 1.5 times as long as clava. Third valvula about 0.3 times as long as second valvifer.

Distribution. Australia: Queensland.
Host. There is only the very questionable host record of the type specimens (Eriococcidae).

Comments
Girault's original description differs from the type specimens in that they do not have a dark band behind the marginal vein. It is possible that Girault described the species when they were still card mounted before he mounted them on a slide with the wings folded over the dark brown gaster, erroneously assuming that they have a dark band (and there are indications in the text, e.g. colour characters which are easier to see in card-than in slide-mounted specimens). No lectotype was designated because the heads of the two females on the slide are separated from the body and no unequivocal assignment is possible.

Redescription
Female. Colour: head brown. Mesosoma brown except following parts yellow: mesoscutum posteriorly, posteromesal corner of axilla, scutellum, and metanotum. Gaster predominantly brown or basal tergites paler. Antenna yellow. Fore wing with dark band behind marginal vein. Legs yellow except mid and hind coxae and occasionally hind femur brown.
Distribution. Australia: New South Wales, Queensland, Western Australia.

Redescription (holotype)
Female. Colour: body orange yellow, head pale yellow green, antenna and legs pale yellow. Wings hyaline.
Morphology: stemmaticum with rugose-reticulate strigose surface sculpture. Antennal formula 1,1,4,2, clava not very distinct. Pedicel longer than F1 (1.24). F1 almost two times as long as its maximum width (1.89), shorter than F2 (0.85) and F3 (0.71). F2 slightly shorter than F3 (0.83). F1 and F2 without longitudinal sensilla, F3 with one or two, F4 with three distinct, and each claval segment with three distinct sensilla. Scutellar sensilla rather closely placed (approximately three to four times the maximum width of a sensillum). Distance between anterior pair of scutellar setae appearing less than distance between posterior pair. Fore wing about 3.1 times as long as width of disc. Marginal fringe about half as long as width of disc (0.52 midtibia slightly longer than half the length of the corresponding basitarsus (0.60). Tergites laterally with the following numbers of setae: T1: 0, T2: 2, T3: 2, T4: 2, following segments indiscernible. Ovipositor slightly longer than midtibia (1.15). Third valvula relatively long, half as long as second valvifer.

Comments
The species is similar to E. bothrocera from Taiwan and E. perflava from China and India, and perhaps is conspecific with one of the two. Females of several species in the perflava group are very similar but males are strikingly different. However, for many species in this species group males have not been associated with females. See also comments on E. antiopa which could represent the male of E. justicia.

Male. Unknown.
Species group placement. Not established.

Comments
Encarsia leptosa is similar to E. pilosa but can be separated by having fewer setae on the mesoscutal midlobe, presence of a medial furrow on the scutellum, lack of a clava, and twosegmented maxillary palp. (Girault) ( Figures 144-146
Morphology: antennal formula 1,1,3,3. Pedicel longer than F1 (1.3). F1 1.55 times as long as its maximum width, shorter than F2 (0.77) and F3 (0.77). F2 and F3 subequal in length. Midlobe of mesoscutum with four setae. Scutellar sensilla widely separated (approximately eight times the maximum width of a sensillum). Distance between anterior pair of scutellar setae subequal to distance between posterior pair. Fore wing about 2.9 times as long as width of disc. Marginal fringe 0.54 times as long as width of disc. Submarginal vein with two setae, marginal vein anteriorly with 11 setae. Basal cell with a single seta. Tarsal formula 5-5-5. Apical spur of midtibia longer than half the length of the corresponding basitarsus (0.71). Basitarsus of middle leg apically with distinct spine. Tergites laterally with the following numbers of setae: T1: 0, T2: 1, T3: 1, T4: 1 (setation of following tergites indiscernible). Ovipositor subequal in length to midtibia and 1.24 times as long as clava. Third valvula approximately 0.43 times as long as second valvifer.

Male. Unknown.
Species group placement. Not established.

Diagnosis
Female. Colour: head and body completely yellow except ocellar triangle with brown spot and antenna brown towards apex. Fore wing hyaline. Legs yellow.
Morphology: stemmaticum with indiscernible surface sculpture. Antennal formula 1,1,4,2. Pedicel subequal in length to F1. F1 2.17 times as long as its maximum width, subequal in length to F2 and F3. Flagellomeres with the following numbers of sensilla: F1: 0, F2: 0, F3: 1, F4: 1, F5: 2, F6: 2. Midlobe of mesoscutum with six setae, four near anterior and two near posterior margin, setae with very distinct bases of equal diameter, side lobes with two setae each, placed in the centre of the anterior third of the axilla. Scutellar sensilla close together, separated by a distance of about half the width of a sensillum. Distance between anterior pair of scutellar setae distinctly smaller than between posterior pair. Fore wing 2.4 times as long as width of disc. Marginal fringe 0.31 times as long as width of disc. Submarginal vein with two setae, marginal vein anteriorly with six setae. Basal cell with three or four setae. Tarsal formula 5-5-5. Apical spur of midtibia subequal in length to the corresponding basitarsus. Tergites laterally with the following numbers of setae: T1: 0, T2: 1, T3: 1, T4: 1, T5: 3, T6: 3, T7 with four setae. Ovipositor longer than middle tibia (1.45) and 2.85 times as long as clava. Third valvula 0.6 times as long as second valvifer. Basal seta of third valvula removed from base about 0.4 along the length of the valvula.
Male. Body dark brown, mesoscutellar midlobe posteriorly, scutellum and legs lighter. Head brown except vertex with paler areas. Antenna pale, second and third funicular segments with distinct glandular complex (Pedata et al. 1995), apical two segments fused.
Species group placement. E. lutea group.

Redescription
Female. Colour: head yellow except stemmaticum brown. Mesosoma yellow, pronotum, anterior margin of mesoscutal midlobe and T1 anteriorly more or less brown; following tergites laterally very slightly brown and T3-T6 with very faint transverse brown band. Antenna yellow. Fore wing hyaline. Legs yellow.

Comments
The species is similar to E. protransvena, but with broader fore wing (2.4 times as long as wing width, whereas it is 2.6-2.8 times in protransvena), setae on mesoscutal midlobe of similar size (in protransvena the anterolateral and posterior setae are much stouter than the medial setae), and body with brown colour pattern (protransvena is completely yellow). (Girault) ( Figures 174-176
Morphology: antennal formula 1,1,3,3, apical segment appears conical. Pedicel subequal in length to F1. F1 about two times as long as its maximum width, subequal in length to F2, and slightly shorter than F3 (0.83). F2 slightly shorter than F3 (0.83). Scutellar sensilla widely separated. Fore wing about 2.8 times as long as width of disc. Marginal fringe 0.39 times as long as width of disc. Basal cell with three setae. Marginal vein anteriorly with eight setae. Tarsal formula 5-5-5. Apical spur of midtibia distinctly longer than half the length of the corresponding basitarsus (0.75). Ovipositor longer than midtibia (1.75) and 2.17 times as long as clava. Third valvula 0.27 times as long as second valvifer.
Male. No males of the species were collected. For a description of E. mineoi males from elsewhere see Polaszek et al. 1999, p 158. The males are hyperparasitoids (Pedata, personal communication).

Redescription
Female. Colour: head yellow except postgena with transverse brown band on vertex partly, malar space and area around mouth brown. Mesosoma mostly yellow, pronotum, mesoscutal midlobe anteriorly and axillae anteriorly more or less brown. Metasoma dark brown except petiole lighter and apex of T7 yellow. Antenna yellow with apical segments darker. Fore wing with dark band behind marginal vein. Legs yellow, hind coxa occasionally brown.

Male. Unknown.
Species group placement. Not established.

Comments
The species is similar to Encarsia synaptocera Huang and Polaszek but has only two setae on the mesoscutal side lobe (synaptocera has three), the scutellar sensilla are further apart, and the gaster is only laterally brown, whereas in synaptocera the gaster is centrally brown. Females of several species in the perflava group are very similar but males differ strikingly from each other. However, males are unknown for this and many other species of the perflava species group. ) Encarsia oakeyensis Schmidt andNaumann in Schmidt et al. 2001, p 381. Holotype R, Australia, Queensland, Oakey, 25 June 1997 (D. R. Lea), ex Trialeurodes vaporariorum on Lactuca serriola L. (Asteraceae) (ANIC, examined).

Comments
Encarsia obliqua is one of the few known Encarsia species with an obliquely truncate clava and an oblique sulcus between F5 and F6, characters which are characteristic for members of the E. noyesi species group. Until recently it was included in Encarsiella (Schmidt and Polaszek 2007).
Male. Head pale, antennae light brown. Mesosoma yellow except pronotum, mesonotum anteriorly and axillae largely brown. Metasoma brown except pale at base and at apex. Legs pale. Apical two segments of antennae fused, but sensilla not or only very slightly overlapping.
Male. Head and body predominantly brown, midlobe of mesoscutum, scutellum, and legs lighter.
Species group placement. E. parvella group. Placed in E. pergandiella group by Viggiani and Mazzone (1979) and Viggiani (1993), and in E. parvella group by Hayat (1989aHayat ( , 1998 and , which these authors consider encompasses the E. pergandiella group.
Male. No males were collected in the study area. For a description of males from elsewhere see Huang and Polaszek (1998

Redescription (lectotype)
Female. Colour: head and mesosoma yellow, gaster dark brown. Antenna yellow. Fore wing with dark band behind marginal vein. Legs yellow. Morphology: antennal formula 1,1,3,3. Collapsed antenna apparently with pedicel slightly longer than F1 and F1 slightly shorter than F2 and F3. F2 subequal in length to F3. Midlobe of mesoscutum with four setae. Scutellar sensilla indiscernible, but distance between anterior pair of scutellar setae greater than between posterior pair, indicating distantly placed sensilla. Fore wing about 2.7 times as long as width of disc. Marginal fringe 0.30 times as long as width of disc. Basal cell with three setae. Submarginal vein with one seta, marginal vein anteriorly with five setae. Tarsal formula 5-5-5. Apical spur of midtibia distinctly longer than half the length of the corresponding basitarsus (0.81). Ovipositor shorter than midtibia (0.83). Third valvula slightly less than half the length of the second valvifer.

Male. Unknown.
Species group placement. Not established. Longitudinal sensilla present on flagellar segments 2-6. Midlobe of mesoscutum with eight setae, arranged symmetrically. Scutellar sensilla separated by about three times the maximum width of a sensillum. Distance between anterior pair of scutellar setae subequal to distance between posterior pair. Fore wing about 3.0 times as long as width of disc. Marginal fringe 0.32 times as long as width of disc. Basal cell with four setae. Marginal vein anteriorly with six setae. Tarsal formula 5-5-5. Apical spur of midtibia distinctly longer than half the length of the corresponding basitarsus (0.8). Ovipositor distinctly longer than midtibia (1.43) and twice as long as clava. Third valvula 0.28 times as long as second valvifer.

Male. Unknown.
Species group placement. E. inquirenda group sensu Hayat (1989a Female. Colour: head brown. Mesosoma brown except mesoscutal midlobe posteriorly and laterally lighter, and mesoscutal side lobes posteriorly, scutellum, and metanotum yellow. Metasoma brown, apical tergite occasionally yellow. Antenna yellow, radicle brown. Fore wing hyaline, venation brown, occasionally with dark infuscation behind proximal half of marginal vein. Legs yellow except mid and hind coxae and hind femur brown. Morphology: stemmaticum with rugosely strigose surface sculpture. Antennal formula 1,1,4,2. Pedicel half as long as F1. F1 2.22-2.46 times as long as broad, subequal in length to F2 and F3. Flagellomeres each with 8-10 longitudinal sensilla. F1-F5 cylindrical and similar in shape and size, F6 conical and slightly shorter than preapical segment. F1-F5 apically with papillar sensilla. Mid lobe of mesoscutum with about 60-70 setae, evenly reticulate, side lobes with three setae each. Posterior pair and lateral setae of mesoscutal midlobe larger than remaining setae. Scutellar sensilla separated by approximately three to four times the width of a sensillum. Distance between anterior pair of scutellar setae smaller than distance between posterior pair, anterior pair located at least slightly anterior to scutellar sensilla. Fore wing 2.1 times as long as width of disc, densely setose, setation of disc slightly more dense than area behind marginal vein. Basal cell with 14-16 setae. Longest setae of marginal fringe about one-tenth the width of disc. Submarginal vein with three to five setae, marginal vein anteriorly with 10-12 setae. Apical spur of midtibia longer than half the length of the corresponding basitarsus (0.77-0.89). Mid tarsus 0.6 times as long as mid tibia. Basitarsus of mid leg ventrally with stout setae with distinct bases, almost as long as combined length of three following tarsal segments. Tergites on each side with the following numbers of setae: T1: 2-4, T2: 4-6, T3: 5-7, T4: 7-8, T5: 12-16, T6: 3-4, T7 with four to six setae. Ovipositor slightly longer than midtibia (1.06-1.09). Third valvula 0.34-0.35 times as long as second valvifer.
Male. Colour and structural details similar to female, but brown colour more extensive.
Species group placement. Not established.
Male. No males of the species were collected in the study area. For a description of E. protransvena males from elsewhere see Heraty and Polaszek 2000, p 160.

Male. Unknown.
Species group placement. Not established.
Host. Unknown. Female. Colour: the holotype is clearly a teneral specimen and the dark colour pattern of the mesosoma is expected to be different in normal specimens. The type has a brown head and mesosoma with the following dark brown markings: pronotum, mesoscutal midlobe with a medial stripe, beginning broadly at the anterior margin, becoming constricted, dilated, and constricted again, and ending well before posterior margin, side lobes anteriorly and along mesal margin, axilla except posteromesal corner, scutellum with pair of dark maculae posterior of scutellar sensilla, within area enclosed by anterior and posterior pair of scutellar setae, mesopleuron and propodeum brown. Gaster pale except first tergite anteriorly brown. Antenna yellow. Fore wing hyaline. Legs yellow. Morphology: stemmaticum with reticulate surface sculpture. Antennal formula 1,1,4,2. Pedicel longer than F1 (1.22). F1 short, 1.6 times as long as its maximum width, distinctly shorter than F2 (0.60) and F3 (0.58). F2 subequal in length to F3. Flagellomeres with the following numbers of sensilla: F1: 0, F2: 2, F3: 4, F4: 4, F5: 4, F6: 1. Midlobe of mesoscutum with 10 setae plus two setae in an asymmetrical position on the left side of the midlobe near the centre which may be missing in other specimens, side lobes with three setae each. Axillary seta located at about one-third the length of the axilla from its anterior margin. Scutellar sensilla widely separated (approximately four times the maximum width of a sensillum). Distance between anterior pair of scutellar setae distinctly smaller than between posterior pair. Fore wing about 2.2 times as long as width of disc. Marginal fringe 0.18 times as long as width of disc. Submarginal vein with two setae, marginal vein anteriorly with 9-10 setae. Basal cell with four to five setae. Stigmal vein very narrow, without distinct constriction. Tarsal formula 5-5-5. Apical spur of midtibia distinctly longer than half the length of the corresponding basitarsus (0.83). Tergites laterally with the following numbers of setae: T1: 0, T2: 1, T3: 1, T4: 1, T5: 3, T6: 3, T7 with four setae. Ovipositor subequal in length to midtibia, with blunt apex. Third valvula relatively long, 0.68 times as long as second valvifer.
Distribution. Australia: New South Wales.

Comments
Teneral specimens with a similar colour pattern are known to occur in other Encarsia species, e.g. E. formosa (A. Polaszek, personal observation), in particular if the specimens were reared. Apart from the unusual pattern of dark markings on the mesosoma, there are additional characters that indicate the presence of a teneral specimen, including the wings which are very pale (including the venation) and appear crumpled. Furthermore, the reticulation of the mesosoma is discernible only in dark coloured areas, suggesting that both the sculpture and the pigmentation develop in patches. Despite this abnormality, the species can be distinguished from closely related species of the inaron group by the relatively long third valvula.
79. Encarsia seminigriclava (Girault) ( Figures 251-253 widely separated. Fore wing about 2.6 times as long as its maximum width. Basal cell with six setae. Marginal fringe 0.33 times as long as width of disc. Marginal vein anteriorly with eight setae. Tarsal formula 5-5-5. Apical spur of midtibia distinctly longer than half the length of the corresponding basitarsus (0.77). Ovipositor distinctly longer than midtibia (2.39) and 2.97 times as long as clava. Third valvula 0.34 times as long as second valvifer.

Comments
Encarsia socratis is characterized by its very long ovipositor which identifies it as belonging to the E. opulenta species group. Encarsia socratis can be separated from other Australian species of the opulenta group (E. albiscutellum, E. iris, E. longicauda, and E. subhyalina n. sp.) by its longer marginal fore wing fringe and the longer ovipositor. with four setae. Ovipositor shorter than midtibia (0.71-0.73) and 1.03-1.13 times as long as clava. Third valvula 0.48-0.53 times as long as second valvifer.

Male. Unknown.
Species group placement. Not established.

Comments
Characterized by the long midtibial spur, the short ovipositor, and the stout antenna with the first funicular segment quadrate. 84. Encarsia stirlingia n. sp. (Figures 269-272)
Distribution. Australia: Queensland, Western Australia.  The species is similar to E. perplexa, but F1 is transverse in perplexa and quadrate in subhyalina, and the gaster has the T5 largely dark in subhyalina whereas it is pale in perplexa. (Girault) ( Figures 276, 277

Redescription
Female. Colour: head pale brown, stemmaticum darker. Antennae pale. Mesosoma brown, the side lobes of the mesoscutum paler, scutellum white in striking contrast to the remainder of the mesosoma (though appearing dark under transmitted light because the specimen has not been cleared). Metasoma brown. Fore wing hyaline. Legs pale except the hind coxae which are brown.
Male. Not collected in the study area. Males from elsewhere are very similar to females in both colour and morphology. Antenna eight-segmented, slight fusion occurring between F5 and F6.
Species group placement. E. tristis group.

Comments
The species is recognized by the short ovipositor and the almost quadrate two distal funicular segments. Girault recorded the species from Australia in 1919 (Girault 1919, p 53) but his material could not be located. In his publication Girault writes that he reared three females from pupae of the sugarcane whitefly, Aleyrodes bergi (5Neomaskellia bergii), at Gordonvale, Queensland, on cane, on 9 December 1918. The species has a peculiar colour pattern in that it has two black spots on the mesosoma (i.e. the axillae are black) contrasting with the remaining yellow mesosoma. Also quite unusual are the stout antennae with segments two and three short to almost quadrate. 91. Encarsia uncinata n. sp. (Figures 288-291)

Comments
The species is characterized by the long marginal fore wing fringe, the sparse setation of the wings, and the conical F6. It is similar to inquirenda but differs by having the F1 subquadrate and distinctly shorter than F2 (longer than broad and subequal in length to F2 in inquirenda) and the ovipositor slightly longer than the middle tibia (subequal in inquirenda). Museum, London, UK) for the identification of whitefly adults. Identifications of whitefly and scale insect host plants by Alice Wells (Australian Biological Resources Study, Canberra, Australia) and staff of the Australian National Botanic Gardens in Canberra is also gratefully acknowledged. The Australian Biological Resources Study is gratefully acknowledged for financial support of part of this study, which was otherwise largely funded by CSIRO, and we acknowledge in particular the support of Paul De Barro. Sincere thanks to Emilio Guerrieri, John Noyes, and Paolo Pedata for their reviews of, and comments on, the manuscript of this paper, which led to great improvements, particularly in the key.