Synergus duricorius Gillette, 1896

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 : 46-48

publication ID	https://doi.org/ 10.11646/zootaxa.4906.1.1
publication LSID	lsid:zoobank.org:pub:09383AAD-8E30-4E50-A533-C6DA4D00E33C
DOI	https://doi.org/10.5281/zenodo.4447541
persistent identifier	https://treatment.plazi.org/id/03BF702A-9528-FFED-FDE5-FA8D72B7FD2E
treatment provided by	Plazi
scientific name	Synergus duricorius Gillette, 1896
status

Treatment

( Figure 16 View FIGURE 16 )

Synergus duricoria Gillette, 1896 . Trans. Am. Entomol. Soc. 23: 93. Type material: USNM.

Type material (examined). HOLOTYPE ♀ with the following labels: ‘Del.’ (white label) / ‘ Ac. Cat. 166’ (orange label) / ‘Biol. 2’ (white label) / ‘Type’ (white label) / ‘ Type No. 27942 U.S. N.M’ (red label) / ‘AccNo 71950, USNM to be loaned only to ColoAgCol’ (white label) / ‘ Synergus duricoria n. sp. ’ (white label, handwritten) / ‘USNMENT 00802038’ (white label, QR code) / ‘ Holotype ♀ Synergus duricorius Gillette, 1896 ’ (red label).

Other material examined (1♂ & 1♀). Material deposited in USNM with the following labels: ‘ U.S.A., Minnesota, Anoka County, Cedar Creek Natural History Area, Spr. Sum. 1983, J. Brokaw’ (white label) / ‘Commensal-Parasite in galls of Disholcaspis quercusmamma on Quercus macrocarpa ’ (white label, handwritten) / ‘20’ (yellow label, handwritten) / ‘ Synergus duricoria Gillette’ (white label) / ‘ USNM 2032352’ (white label).

Diagnosis. Synergus duricorius belongs to a group of species characterized by having the mesopleuron entirely sculptured, covered with non-parallel, transverse striae, somewhat reticulated anteriorly; hyaline wings and radial cell of fore wing at most 2.5 times as long as wide; gena not broadened behind eye; POL longer than OOL; F1 as long as F2 and female antenna with 14 segments; lateral pronotum wrinkled or carinated, at least ventrally; mesoscutum with transversal carinae, interspaces sculptured; notauli complete, reaching the posterior margin of pronotum; tarsal claws with a distinct basal lobe; first metasomal segment completely sulcate dorsally and laterally; syntergum with a posterior band of micropunctures; and body of females at least with some dark surfaces, never completely yellowish. Synergus duricorius differs from the species sharing these traits ( S. beutenmulleri and S. linnei, sp. nov., see below) by having a narrow band of micropunctures posteriorly on the syntergum, which extends at most 1/5 of its length (a wide band extended laterally somewhat more than 1/2 of its length in these species, Figs 6h View FIGURE 6 ; 22h View FIGURE 22 ); tarsal claws with a small basal lobe (strong in these species, Figs 6e View FIGURE 6 ; 22e View FIGURE 22 ); and body of females mostly yellow, head only with a black spot in the ocellar area ( Fig. 16c View FIGURE 16 ) (frons, vertex and occiput, black in these species, Fig. 5e View FIGURE 5 ), among others (see the identification key).

Redescription

FEMALE. Length. Body length about 4.0 mm (n = 2).

Color ( Fig. 16 View FIGURE 16 ). Mainly yellow. Head yellow, except for a black spot in the ocellar area and the area surrounding the occipital foramen, which is black. Antenna yellow. Mesosoma mainly yellow, space between coxae and propodeum, black; tegulae light yellow. Metasoma mainly yellow, the first metasomal segment and the syntergum dorsally, black. Legs yellow, metatarsi darker. Wings hyaline, veins brown.

Head. In frontal view trapezoid, 1.2 times as wide as high, gena not broadened behind eye. Face faintly pubescent, lower face with striae radiating from clypeus. Clypeus indistinct, ventral margin slightly projected over mandibles. Malar space about 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 mid-height of eye; distance between torulus and eye shorter than diameter of torulus; distance between toruli shorter than diameter of toruli. Frons ( Fig. 16c View FIGURE 16 ) coriaceous with some scattered punctures between frontal carinae, weakly wrinkled outside carinae; frontal carinae narrow and branched, reaching lateral ocelli. Head in dorsal view is about 2.1 times as wide as long. Vertex ( Fig. 16c View FIGURE 16 ) weakly wrinkled and punctate. POL: OOL: LOL = 12.5: 8: 6 and diameter of lateral ocelli, 6.5. Occiput weakly reticulated, without punctures.

Antenna ( Fig. 16a View FIGURE 16 ). 14-segmented; filiform, not broadened apically; almost as long as the body; pubescence dense and short. Scape plus pedicel about as long as F1; pedicel almost 1.4 times as long as wide; F1 as long as F2, F2 and F3 subequal; the following segments progressively shorter. Last flagellar segment about 3.5 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. 16a View FIGURE 16 ). Ratio of length of pronotum medially/laterally: 0.27. Pronotal plate indistinct. Lateral pronotum weakly wrinkled; lateral carina absent, lateral margins of pronotum rounded seen from above. Mesoscutum ( Fig. 16b View FIGURE 16 ) about 1.2 times as wide as long, with dense but weak discontinuous carinae, interspaces alutaceous; anterior parallel lines weakly impressed, reaching somewhat more than 1/3 of the mesoscutum; notauli complete and visible in their whole length but shallow and narrow, less impressed anteriorly; median mesoscutal line absent; parapsidal lines shallowly impressed, narrow, reaching tegulae. Mesoscutellum ( Fig. 16b View FIGURE 16 ) about 1.2 times as long as wide, wrinkled; circumscutellar carina weak, almost inconspicuous, obscured by wrinkles; scutellar foveae large, more or less ovate, shallow, weakly sculptured bottom and separated by a narrow carina. Mesopleuron completely irregularly striated. Metapleural sulcus reaching about 3/4 of mesopleural height. Propodeum pubescent and weakly sculptured; propodeal carinae straight and parallel. Nucha sulcate dorsally and laterally.

Legs. Tarsal claws with a small basal lobe.

Wings. Fore wing pubescent with short marginal setae, about as long as the body length ( Fig. 16a View FIGURE 16 ). Radial cell closed, about 2.4 times as long as wide; areolet visible but small, all veins well pigmented. Rs+M visible, almost reaching the basal vein. Basal cell with sparsely spaced setae.

Metasoma. About as long as head plus mesosoma and about 1.3 times as long as high in lateral view ( Fig. 16a View FIGURE 16 ). First metasomal segment sulcate dorsally and laterally. Syntergum smooth, anterolateral pubescence composed of a few setae and posteriorly with a narrow band of micropunctures extended about 1/5 of its length; strongly dorsodistally incised, not pointed. Hypopygial spine about as long as wide and with a few lateral setae; without apical setae.

MALE. Similar to female, except for the following: body length 3.5 mm (n = 1). Antenna 15-segmented; F1 straight, almost not incised medially and very slightly broadened apically and basally. Malar space almost 0.7 times as long as height of eye. Metasoma shorter than head plus mesosoma, the band of micropunctures less widespread. Frons and vertex medially, and occiput, black; lower face and gena light yellow; mesosoma mainly black, dorsolateral pronotum, mesopleural triangle and tegulae, yellow; metasoma yellow, the dorsal black band extended laterally; legs light yellow.

Distribution. USA: Delaware ( Gillette 1896) and Minnesota (authors).

Biology. Reared from galls of Disholcaspis quercusmamma (Walsh, 1869) ( Gillette 1896; authors) on and oak from Quercus section ( Pénzes et al. 2012) and on Q. macrocarpa (authors).

Remarks. Synergus duricorius was described from a single female ( Gillette 1896: 93), which has been found and examined. Since no more specimens where used to describe this species, the only female composing the type series becomes the holotype.