Synergus ashmeadi Lobato-Vila & Pujade-Villar, 2021

Lobato-Vila, Irene & Pujade-Villar, Juli, 2021, The genus Synergus Hartig (Hymenoptera: Cynipidae: Synergini) in the New World: a complete taxonomic revision with a key to species, Zootaxa 4906 (1), pp. 1-121 : 14-16

Synergus ashmeadi Lobato-Vila & Pujade-Villar , sp. nov.

( Figures 1 , 42a )

urn:lsid:zoobank.org:act:E31901F1-A222-4DC2-948E-FA0A37BC4FF5

Type material. HOLOTYPE ♀ deposited in JP-V coll. ( UB) with the following labels: ‘ MEX: P141, Sierra Fría (Aguascalientes, AGS), 22°11’51.1’’N, 102°35’29.5’’W’ (white label) / ‘Ex. Andricus sp., 2464m, Q. potosina , (14. ii.2011) 17.ii.2011, E. Estrada & A. Equihua leg.’ (white label) / ‘Holotype ♀ Synergus ashmeadi Lobato-Vila & Pujade-Villar , IL-V desig-2020’ (red label). PARATYPE (1♀) deposited in JP-V coll. ( UB) with the same data as the holotype.

Etymology. Named in honor of Mr. William Harris Ashmead (1855–1908), an American entomologist who specialized on parasitic Hymenoptera , including gall wasps.

Diagnosis. Synergus ashmeadi , sp. nov. is the only species that lacks notauli, which at most appear as very shallow, inconspicuous, and hardly traceable grooves visible only under optimal illumination of the specimen. In addition, it is one of a few species that have the mesoscutum uniformly coriaceous-punctate, with conspicuous punctures covering all of the surface ( Fig. 1g ) (usually entirely alutaceous, coriaceous, or more or less carinated in the rest of species). Synergus ashmeadi , sp. nov. is also characterized by having the mesopleuron entirely sculptured, with parallel striae covering all of the surface, including the speculum ( Fig. 1e ); hyaline wings ( Fig. 1a ); and the mesoscutellum medially coriaceous and laterally and posteriorly wrinkled ( Fig. 1g ).

Description

FEMALE. Length. Body length 2.0 mm (n = 2).

Color ( Fig. 1 ). Body black and yellow. Head mainly yellow, vertex and occiput medially and around the occipital foramen, black. Antenna yellow, the tip somewhat darker. Mesosoma mainly black; pronotum yellow or anterolaterally black and the rest, yellow; mesopleuron completely black or with yellow speculum; mesopleural triangle and tegula, yellow. Metasoma black dorsally, yellow laterally and ventrally. Legs pale yellow. Wings hyaline, veins pale yellow.

Head. In frontal view ( Fig. 1b ) trapezoid, about 1.1 times as wide as high, gena not broadened behind eye. Face faintly pubescent, lower face with dense striae radiating from clypeus, reaching eyes and toruli; medial striae short to absent. Clypeus indistinct, ventral margin straight, not projected over mandibles. Malar space about 0.5-0.6 times as long as height of eye. Anterior tentorial pits visible; pleurostomal and epistomal sulcus absent. Transfacial line about as long as height of eye. Toruli situated slightly under mid-height of eyes; distance between torulus and eye about as long as diameter of toruli; distance between toruli slightly longer than diameter of toruli. Frons finely coriaceous, with a few weak wrinkles and very few small piliferous punctures; frontal carinae narrow, branched in their whole length and reaching lateral ocelli. Head in dorsal view ( Fig. 1c ) is 2.0 times as wide as long. Vertex finely coriaceous, with some weak wrinkles and small punctures. POL: OOL: LOL = 6.5: 5.5: 3 and diameter of lateral ocelli, 3. Occiput finely coriaceous, with some weak wrinkles and small punctures.

Antenna ( Fig. 1d ). 14-segmented (7: 4: 12: 11: 11: 10: 8: 8: 6: 5.5: 4.5: 4: 4: 7.5); filiform, not broadened apically; pubescence dense and short; placodeal sensilla visible on flagellar segments F3–F12. Pedicel about 1.6 times as long as wide; F1 slightly longer than F2, F2 as long as F3. Last flagellar segment about 2.5 times as long as wide and almost 2.0 times as long as F11.

Mesosoma. About 1.2 times as long as high in lateral view including nucha, with short and not dense pubescence ( Fig. 1e ). Ratio of length of pronotum medially/laterally: 0.33. Pronotal plate indistinct. Lateral pronotum strongly coriaceous to weakly wrinkled; lateral carina absent, pronotum rounded seen from above. Mesoscutum ( Fig. 1g ) about 1.1 times as wide as long, uniformly coriaceous-punctate; anterior parallel lines shallow but visible, extended about 1/3 of the mesoscutal length; notauli absent, at most with two very weakly depressions on the mesoscutum where notauli are usually present; median mesoscutal line absent; parapsidal lines weakly impressed, reaching tegulae. Mesoscutellum ( Fig. 1g ) rounded, almost as long as wide, anteriorly coriaceous, posteriorly and laterally wrinkled, interspaces coriaceous; circumscutellar carina weak but visible, somewhat obscured by wrinkles, not projected; scutellar foveae subquadrate to ovate, well impressed and delimited, the bottom with longitudinal weak carinae and separated by a narrow carina. Mesopleuron ( Fig. 1e ) regularly and densely striated, interspaces finely coriaceous anteriorly; slightly pubescent basally. Metapleural sulcus reaches about 3/4 parts of mesopleural height. Propodeum weakly sculptured; propodeal carinae almost straight and parallel. Nucha weakly sulcate dorsally and laterally.

Legs. Tarsal claws with a basal lobe.

Wings. Fore wing pubescent with short marginal setae, slightly longer than body length. Radial cell closed, about 2.5 times as long as wide; areolet inconspicuous, only the posterior vein somewhat pigmented ( Fig. 1h ). Rs+M inconspicuous, almost reaching the basal vein. Basal cell with sparsely spaced setae.

Metasoma. Shorter than head plus mesosoma, almost as high as long in lateral view ( Fig. 1f ). First metasomal segment sulcate dorsally and laterally. Syntergum smooth, with an anterolateral pubescence composed of very few setae and posteriorly with an incomplete band of micropunctures extended almost 1/3 of its length, less widespread dorsally ( Fig. 1f , dot line); not dorsodistally incised, pointed. Hypopygial spine almost 3.0 times as long as wide (very narrow) and with a few lateral setae; without apical setae.

MALE. Unknown.

Distribution. Mexico: Aguascalientes.

Biology. Reared from tuberous galls induced by an undetermined species of Andricus ( Fig. 42a ) on Q. potosina .

Figures

FIGURE 1. Synergus ashmeadi Lobato-Vila & Pujade-Villar, sp. nov. (female): a) lateral habitus; b) head in frontal view; c) head in dorsal view; d) antenna; e) mesosoma in lateral view; f) metasoma in lateral view; g) mesosoma in dorsal view; h) radial cell of the fore wing.

FIGURE 42. a) Andricus sp. (Ref.: MEX: P141); b) Andricus sp. (Ref.: MEX: P230); c) Melikaiella bicolor (Ref.: MEX: 044, 049, P026, P071); d) Sphaeroteras sp. (Ref.: MEX: P024); e) Undetermined genus (Ref.: MEX: P184); f) Neuroterus sp. (Ref.: MEX: P386, P388); g) Disholcaspis sp. (Ref: MEX: P398); h) Femuros nr repandae (Ref.: P187, P227, 2797); i) Femuros repandae (Ref.: MEX: P313, 255, 256); j) Andricus sp. (Ref.: MEX: P314); k) Disholcaspis sp. (Ref.: MEX: P140); l) Undetermined genus (Ref.: MEX: P259); m) Neuroterus sp. (Ref.: MEX: P381); n) Loxaulus hyalinus (Ref.: MEX: 333); o) Undetermined genus (Ref.: Clark-49); p) Atrusca sp. (Ref.: P317, P318); q) Atrusca sp. (Ref.: MEX: P183); r) Andricus sp. (Ref.: MEX: P394); s) Andricus sp. (Ref.: MEX: P038).