Encarsia hera Lahey & Andreason, 2022

Lahey, Zachary, Simmons, Alvin M. & Andreason, Sharon A., 2022, Encarsia hera Lahey & Andreason (Hymenoptera, Aphelinidae): a charismatic new parasitoid of Aleurocybotus Quaintance & Baker (Hemiptera, Aleyrodidae) from Florida, Journal of Hymenoptera Research 94, pp. 89-104 : 89

Encarsia hera Lahey & Andreason sp. nov.

Figs 1-3 , 4 , 5

Species-group placement.

Encarsia luteola -group.

Diagnosis.

Encarsia hera , sp. nov., can be differentiated from other members of the E. luteola -group by outstanding coloration of the mesoscutellum and metasoma. Most E. luteola -group species have a concolorous mesoscutellum and a predominately yellow metasoma. Encarsia hera , sp. nov., differs from these species by the paired brown patches in the posterior half of the mesoscutellum and the predominantly brown metasoma of the female. Encarsia guadeloupae Viggiani also has a dark metasoma; however, in that species T1 is completely dark and the clava is 2-merous, whereas the lateral portions of T1 are yellow and the clava is 3-merous in E. hera , sp. nov.

Description

(female). Coloration. Body: predominately dark brown. Head: dark brown, except for pale areas on frons adjacent to compound eyes and a transverse strip on vertex anterior to ocellar bars. Antenna: yellow, except for fuscous apical clavomere (F6). Mesosoma: dark brown, except for yellow lateral and posteromedial margin of mesoscutum, mesoscutal side lobe, anterodorsal portion of acropleuron, and most of mesoscutellum. Mesoscutellum: predominately yellow with two conspicuous brown spots in posterolateral half. Fore and hind wings: hyaline, venation fuscous. Legs: pale yellow, except for fuscous apical tarsomere (tarsomeres 4 + 5 fused) on midleg and apical three tarsomeres on hindleg. Metasoma: dark brown, except for lateral portions of T1 which appear transparent/opalescent. Ovipositor: third valvulae yellow.

Head. Antennal formula: 1-1-3-3. Length of pedicel relative to F1: 0.8. Length of F1 relative to F2: 0.9. Length of F2 relative to F3: approximately equal. Number of multiporous plate sensilla on F1-F6: 1-2-2-3-3-3. Sculpture of stemmaticum: aciculate. Sculpture of frons ventral to transfacial line: indiscernible. Sculpture of frons dorsal to transfacial line: transversely imbricate.

Mesosoma. Number of setae on midlobe of mesoscutum: 16. Number of setae on side lobe of mesoscutum: 2. Number of setae on axilla: 1. Proximity of campaniform sensilla on mesoscutellum: ≥ 5 sensillar widths apart. Distance between anterior pair of mesoscutellar setae: equal to distance between posterior pair of mesoscutellar setae. Length of mesoscutellar setae: anterior pair distinctly shorter than posterior pair. Tarsal formula: 5-4-5. Length of midtibial spur: 0.8 × length of midbasitarsus.

Metasoma. Number of paired setae on T1-T6: 0-1-2-1-3-3. Length of ovipositor: 0.8 × length of midtibia. Apical portion of 3rd valvulae: chisel-tipped, inner margin longer than outer margin. Length of 3rd valvulae relative to 2nd valvifer: 0.7 ×.

Wings. Length of fore wing: 2.7 × width. Asetose area below stigma vein: absent. Length of marginal fringe: 0.3 × maximum width of disc. Number of setae in basal cell region: 5. Arrangement of setae in basal cell: linear, originating and forming a 45° angle with submarginal vein. Number of setae on submarginal vein: 2. Number of setae along anterior of marginal vein: 8; 9.

Description

(male). Coloration. Same as female, except for the darker mesoscutellum and T1 is dark throughout.

Morphology. Sculptural patterns very similar to female. Mesoscutellar sculpture: weak medially, large reticulations laterally. Number of antennomeres: 8. Condition of F6: articulate with F5, not fused or partially fused.

Distribution.

Florida (USA).

Host.

Aleurocybotus sp. nr. cereus ( Hemiptera : Aleyrodidae ).

Etymology.

Named for the Hera of Greek mythology, one of the Twelve Olympians, Queen of the Gods, and protector of women from harm during childbirth.

Material Examined.

Holotype, female: USA: Florida, Gainesville , 29°36'3"N, 82°25'13"W, 19.vi.2022, ex. Aleurocybotus n. sp. on ornamental Muhly grass ( Muhlenbergia capillaris ), Z. Lahey, OSUC 863846 (deposited in USNM) . Paratypes: USA: collection data identical to holotype, 1 female, 2 males, OSUC 863847 (USNM); OSUC 863886, 863887 (FSCA) .

Phylogenetic analyses.

The alignment of the 28S-D2-3 region in the 36 taxa was 1,037 characters long (base pairs plus gaps) and the model of nucleotide evolution was SYM+I+G4. In all analyses, the E. luteola -group was recovered as monophyletic with maximum ultrafast bootstrap support (UFBS = 100; Fig. 9 ). Encarsia hera , sp. nov., was nested within the E. luteola -group, as the sister taxon to E. formosa Gahan (UFBS = 99; Fig. 9 ), and E. luteola Howard was recovered as the sister taxon to E. hera sp. nov. + E. formosa (UFBS = 95; Fig. 9 ). An expanded analysis of the same gene region with additional Encarsia species recovered the same sister group relationships between E. luteola , E. hera sp. nov., and E. formosa as those in Fig. 9 (Suppl. material 1), as did a trimmed version (495 characters) of the original dataset (Suppl. material 2). While this article was in press, we were alerted that two taxa (three sequences) used in the phylogenetic analyses are misidentified in GenBank. The sequences corresponding to accessions AF223366.1 and AF223367.1 belong to E. californica Polaszek and AY360217.1 corresponds to E. dispersa Polaszek. Both E. meritoria Gahan and E. haitiensis Dozier have never been sequenced (A. Polaszek, pers. comm.).

Comments.

Members of the E. luteola -group are recognized by having 4 mesotarsal segments and a fully setose wing disc ( Gahan 1924; Polaszek et al. 1992). This species group has been recovered as monophyletic in several phylogenetic analyses of 28S rDNA (Babcock et al. 2000; Schmidt et al. 2006), although no analysis has yet to include all described species.

The sister group relationship between E. formosa and E. hera , sp. nov., recovered in our study breaks the longstanding paradigm that E. formosa and E. luteola are likely each other’s most closely related living relative ( Babcock and Heraty 2000). This is an interesting finding given the morphological similarity between the two taxa, with certain specimens impossible to distinguish as either species ( Polaszek et al. 1992). Schauff et al. (1996) even mentioned the possibility that E. formosa and E. luteola are conspecific based on the lack of morphological characters that can readily define them. Our analysis brings to light at least one character mentioned by Babcock and Heraty (2000) that allows for the unambiguous identification of E. formosa : the presence of multiporous plate sensilla (MPS) on funicle (F) 1 and 2. Encarsia hera , sp. nov., also possesses this character, whereas E. luteola lacks MPS on F1 and F2, lending morphological credence to the relationships between these three taxa recovered in the molecular analysis.

Figures

Figure 4. Encarsia hera Lahey & Andreason, female paratype (OSUC 863886), habitus, dorsal view. Scale bar in millimeters.

Figure 5. Encarsia hera Lahey & Andreason, male paratype (OSUC 863887), habitus, dorsolateral view. Scale bar in millimeters.

Figure 9. Maximum likelihood phylogeny of the 28 S-D 2 - 3 region in 34 Encarsia and two outgroup species. The number under the scale bar indicates the number of expected nucleotide substitutions per site. Ultrafast bootstrap supports values are indicated by colored circles at nodes. GenBank accession numbers beginning with OP correspond to specimens newly sequenced for this study.

Figures 1 - 3. Encarsia hera Lahey & Andreason, female holotype (OSUC 863846) 1 Antenna, lateral view 2 Mesotarsus, dorsal view 3 Fore wing, lateral view. Scale bars in millimeters.