Synergus oneratus ( Harris, 1841 ), 1864

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 : 76-80

Synergus oneratus ( Harris, 1841)

( Figure 30 )

Cynips oneratus Harris, 1841 . Rpt. Ins. Mass. Injurious to Veg.: 398. Type material: MCZ.

Synergus oneratus: Walsh (1864) . Proc. Entomol. Soc. Phil. 2: 498.

Synergus garryana Gillette, 1893 . Can. Entomol. 25: 110 syn. nov. Type material: USNM.

Synergus oneratus var coloradensis Gillette, 1896 . Trans. Am. Entomol. Soc. 23: 91 syn. nov. Type material: USNM.

Synergus oneratus oneratus: Burks in Krombein et al. (1979) . Smith. Inst. Press 1: 1062.

Synergus oneratus coloradensis: Burks in Krombein et al. (1979) . Smith. Inst. Press 1: 1062.

Type material of Cynips oneratus Harris, 1841 (examined). LECTOTYPE ♀ with the following labels: on the underside of the insect label, it can be read ‘June, July, 1822, small oak galls (handwritten); ‘102 +’ (white label, handwritten) / ‘M.C.Z. Type 26335’ (red label) / ‘Jan–Jul 2005, MCZ Image Database’ (white label) / ‘MCZ-ENT 00026335’ (white label, QR code) / ‘ Lectotype ♀ Cynips oneratus Harris, 1841 IL-V desig-2019’ (red label) / ‘ Synergus oneratus (Harris) Walsh, 1864 ’ (white label).

Type material of Synergus garryana Gillette, 1893 (examined). LECTOTYPE ♀ with the following labels: ‘Wash 1053’ (orange label, handwritten) / ‘Biol 38’ (white label) / ‘Type’ (white label, handwritten) / ‘ Type No. 27946 U.S. N.M.’ (red label) / ‘Acc No 71950 USNM to be loaned only to ColoAgCol’ (white label) / ‘ Synergus garryana ’ (white label with a red frame, handwritten) / ‘USNMENT 00802113’ (white label, QR code) / ‘ Lectotype ♀ Synergus garryana Gillette, 1893 , IL-V desig-2017’ (red label). PARALECTOTYPES (1ϐ & 2♀) with the following labels: ‘Wash 1053’ (orange label, handwritten) / ‘Type’ (white label, handwritten) / ‘11’ (green label, handwritten) / ‘Collection Ashmead’ (white label) / ‘ Paratype No. 27946 U.S. N.M.’ (red label) / ‘ Synergus garryana Gill. ’ (white label, handwritten) / ‘ Paralectotype ♀ Synergus garryana Gillette, 1893 , IL-V desig-2017’ (red label) (2♀); same labels, but ‘ Allotype No. 27946 U.S. N.M.’ (1ϐ) .

Type material of Synergus oneratus coloradensis Gillette, 1896 (examined). LECTOTYPE ♀ with the following labels: ‘Colo 1833’ (white label) / ‘118’ (white label, handwritten) / ‘Type’ (white label, handwritten) / ‘AccNo71950 USNM to be loaned only to ColoAgCol’ (white label) / ‘Type No. 27936 U.S. N.M.’ (red label) / ‘ S. oneratus coloradensis ’ (white label, handwritten) / ‘USNMENT 00779991’ (white label, QR code) / ‘ Lectotype ♀ Synergus oneratus coloradensis Gillette, 1896 , IL-V desig-2017’ (red label) / ‘ Synergus oneratus ( Harris, 1841) , IL-V det. 2019’ (white label). PARALECTOTYPES (2ϐ & 1♀) with the following labels: ‘Colo 1723’ (white label) / ‘Type’ (white label, handwritten) / ‘Coll CF Baker’ (white label) / ‘ Allotype No. 27936 U.S. N.M.’ (red label) / ‘ Synergus oneratus var coloradensis Gill. ’ (red label with a black frame, handwritten) / ‘USNMENT 00960370’ (white label, QR code) / ‘ Paralectotype ϐ Synergus oneratus coloradensis Gillette, 1896 , IL-V desig-2017’ (red label) / ‘ Synergus oneratus ( Harris, 1841) , IL-V det. 2019’ (white label) (1ϐ); ‘Colo 1723’ (white label) / ‘Type’ (white label, handwritten) / ‘Coll CF Baker’ (white label) / ‘ Paratype No. 27936 U.S. N.M.’ (red label) / ‘ USNMENT 00960564’ (white label, QR code) / ‘ Paralectotype ϐ Synergus oneratus coloradensis Gillette, 1896 , IL-V desig-2017’ (red label) / ‘ Synergus oneratus ( Harris, 1841) , IL-V det. 2019’ (white label) (1ϐ); ‘Colo 838’ (white label) / ‘Biol 117’ (white label) / ‘Type’ (white label, handwritten) / ‘Collection Ashmead’ (white label) / ‘ Paratype No. 27936 U.S. N.M.’ (red label) / ‘ Synergus oneratus coloradensis Gill ♀ ’ (white label, handwritten) / ‘USNMENT 00960675’ (white label, QR code) / ‘ Paralectotype ♀ Synergus oneratus coloradensis Gillette, 1896 , IL-V desig- 2017’ (red label) / ‘ Synergus oneratus ( Harris, 1841) , IL-V det. 2019’ (white label) (1♀).

Other material examined (5ϐ & 16♀). Material determined as Synergus oneratus coloradensis deposited in USNM with the following labels: ‘N.Y. 1710’ (white label, handwritten) / ‘Det Gill’ (white label, handwritten) / ‘Coll CF Baker’ (white label) (1ϐ); ‘12070 z2 Hopk US’ (white label) / ‘Reared June 15-15’ (white label) / ‘ USMENT 00960613’ (white label, QR code) (1♀); ‘HopkUS 10773 us’ (white label) / ‘Reared July 2–19’ (white label) / ‘ Quercus gambelii ’ (white label) / ‘ Colorado Springs, Col’ (white label) / ‘JH Pollock Colo’ (white label) / ‘Ex gall of Disholcaspis perniciosa ’ (white label, handwritten) / ‘ Synergus oneratus coloradensis Gill. ’ (white label with a black frame, handwritten) / ‘USNMENT 00960664’ (white label, QR code’ (1♀); ‘12070 z2a Hopk US’ (white label) / ‘Reared June 28–15’ (white label) / ‘ Quercus undulata ’ (white label) / ‘N. Cheyenne Canyon, Colo.’ (white label) / ‘Champlain AB Colr’ (white label) / ‘ Synergus oneratus coloradensis, Midd. det.’ (white label with a black frame, handwritten) / ‘Ex. Dish. rubens ’ (white label, handwritten) / ‘USNMENT 00960623’ (white label, QR code) (1♀); ‘13604 c’ Hopk. U.S. ’ (white label) / ‘Reared June 4– 15 W. Middleton’ (white label) / ‘USNMENT 00960417’ (white label, QR code) (1ϐ & 7♀). Material determined as Synergus garryana deposited in USNM with the following labels: ‘Wash 1317’ (white label, handwritten) / ‘Coll CF Baker’ (white label) / ‘USNMENT 00960012’ (white label, QR code) (3ϐ & 4♀); ‘Camp Baldy, Cal.’ (white label) / ‘ Q. dumosa ’ (grey label) / ‘Bred from gall 1653’ (white label) / ‘ Synergus garryana Gill. ’ (white label with a black frame, handwritten) (1♀); ‘Wash 1317’ (white label, handwritten) / ‘Coll CF Baker’ (white label) / ‘ Synergus garryana Gill’ (red label with a black frame, handwritten) (1♀).

Diagnosis. Synergus oneratus belongs to a group of species characterized by having the mesopleuron entirely sculptured, covered with parallel and fine transverse striae; hyaline wings and radial cell of fore wing at most 2.5 times as long as wide; malar space 0.6 or more times as long as height of eye; transfacial line as long as height of eye; POL longer than OOL; OOL 1.2–1.3 times as long as diameter of lateral ocelli; gena not broadened behind eye; F1 as long as F2, antenna 14-segmented in females; lateral pronotum wrinkled or carinated, at least ventrally; mesoscutum with transversal carinae, interspaces sculptured; notauli complete, reaching the posterior margin of pronotum; tarsal claws bidentate, with a distinct and conspicuous basal lobe; first metasomal segment completely sulcate dorsally and laterally; syntergum posteriorly with a complete wide band of micropunctures extended laterally more than 1/3 of its length, weakly to not dorsodistally incised in females; and body of females with some dark surfaces, never completely yellow. Synergus oneratus is morphologically close to S. rutulus (see below), from which differs by having POL 1.6 times as long as OOL ( Fig. 30c ) (1.3 in S. rutulus , Fig. 37c ); mesoscutum with weak, dense and discontinuous transversal carinae and median mesoscutal line absent ( Fig. 30f, j ) (mesoscutum with strong and dense transversal carinae, and median mesoscutal line appearing as a small incision in S. rutulus , Fig. 37b ); radial cell of fore wing 2.3 times as long as wide (2.5 in S. rutulus ); and syntergum of females weakly dorsodistally incised ( Fig. 30a, e, g ) (not incised in S. rutulus , Fig. 37a ), among others (see the identification key).

Redescription

FEMALE. Length. Body length about 2.5–3.5 mm (n = 20).

Color ( Fig. 30 ). Body mainly yellow to black and yellowish orange or rufous. Head yellow, except for a black spot in the ocellar area, to yellow with frons, vertex and occiput black. Antenna yellow with the tip somewhat darker, to dark brown with rufous joints. Mesosoma can be yellow or dark yellow with propodeum and mesosoma basally black; yellow and black, with the mesopleuron entirely black, the mesoscutum with a medial dark strip or completely black; or black, sometimes only with the pronotum posteriorly and base of notauli orange or rufous. Tegulae yellow. Metasoma yellow with a more or less extended dorsal black band, to orange or amber with a dorsal black band. Legs yellow, tarsi blackish. Wings hyaline, veins yellow to testaceous.

Head. In frontal view trapezoid, about 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 straight, not 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 about as long as diameter of torulus; distance between toruli shorter than diameter of toruli. Frons ( Fig. 30e, i ) coriaceous with some weak wrinkles and scarce piliferous punctures; frontal carinae narrow, branched in their whole length, reaching lateral ocelli. Head in dorsal view is about 2.1 times as wide as long. Vertex ( Fig. 30e, i ) coriaceous with some weak wrinkles and scarce piliferous punctures. POL: OOL: LOL = 9: 5.5: 4 and diameter of lateral ocelli, 4.5. Occiput coriaceous with some weak wrinkles.

Antenna ( Fig. 30d, e ). 14-segmented; filiform, not broadened apically; pubescence dense and short. Scape plus pedicel about as long as F1 or slightly shorter; pedicel almost 1.5 times as long as wide; F1 about as long as F2, F2 about as long as F3 or slightly longer; the following segments progressively shorter. Last flagellar segment about 4.0 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. 30a, e, g ). Ratio of length of pronotum medially/laterally: 0.4. Pronotal plate indistinct. Lateral pronotum coriaceous, sometimes with some weak wrinkles basally ( Fig. 30b ); lateral carina absent, lateral margins of pronotum rounded seen from above. Mesoscutum ( Fig. 30f, j ) about 1.2 times as wide as long, with weak and dense, discontinuous transversal carinae; anterior parallel lines visible but shallow, reaching 1/3 of the mesoscutum; notauli complete and usually well impressed in their whole length, sometimes less impressed and visible in the anterior 1/3; median mesoscutal line absent; parapsidal lines weakly impressed, inconspicuous. Mesoscutellum ( Fig. 30f, j ) about as long as wide, wrinkled, interspaces alutaceous; circumscutellar carina well defined and visible, especially seen from above; scutellar foveae ovate to subquadrate, moderately large, shallow, weakly sculptured bottom, the posterior margin not well defined and separated by a narrow carina. Mesopleuron ( Fig. 30e, g ) finely, regularly and densely striated, interspaces smooth. Metapleural sulcus reaching 3/4 of mesopleural height. Propodeum pubescent and alutaceous; propodeal carinae straight and slightly convergent posteriorly. 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. 30d ). Radial cell closed, about 2.3 times as long as wide; areolet visible, small. Rs+M inconspicuous, not reaching the basal vein. Basal cell with sparsely spaced setae.

Metasoma. Slightly shorter than head plus mesosoma and almost 1.2 times as long as high in lateral view ( Fig. 30a, e, g ). First metasomal segment sulcate dorsally and laterally. Syntergum smooth, anterolateral pubescence composed of a few setae and posteriorly with a complete wide band of micropunctures extended somewhat more than 1/3 of its length, less extended dorsally ( Fig. 30g, h ); weakly dorsodistally incised to not incised, not pointed. Hypopygial spine about 2.0 or 3.0 times as long as wide and with a few lateral setae; without apical setae.

MALE. Similar to female, except for the following: body length about 2.0– 2.5 mm (n = 8). Antenna 15-segmented; F1 almost straight, very weakly incised medially and almost not broadened distally nor basally. Metasoma shorter than head plus mesosoma. Body darker; frons, vertex and occiput black; mesosoma completely black; metasoma chestnut; metatibiae and metatarsi dark; antenna progressively darker towards the tip.

Distribution. USA: Massachusetts, New York, New Jersey, Washington D.C., Michigan, Illinois, Iowa ( Harris 1841; Gillette 1896; Burks 1979; authors), Colorado ( Gillette 1896; authors), Washington, and Oregon ( Gillette 1893, 1896; Burks 1979); also from California ( Fullaway 1911; McCracken & Egbert 1922; authors), but this distribution needs to be confirmed; and Canada: Ottawa ( Gillette 1896).

Biology. Reared from galls of Andricus (= Adleria ) quercusstrobilana ( Osten-Sacken, 1862) , Atrusca brevipennata ( Gillette, 1893) , Disholcaspis quercusglobulus ( Fitch, 1859) and D. rubens ( Gillette, 1893) ( Gillette 1896; Burks 1979); from galls very similar to those of Disholcaspis perniciosa (Bassett, 1890) (= Holcaspis monticola Gillette, 1893 ) on Q. garryana ( Gillette 1893) , which may correspond to Disholcaspis eldoradensis (Beutenmüller, 1909) ( Burks 1979) ; from galls of D. eldoradensis on Q. lobata and Q. dumosa ( Fullaway 1911; McCracken & Egbert 1922), even though this record needs to be confirmed; and from galls of D. perniciosa on Q. gambelii , and D. rubens on Q. x undulata , according to the labels of some specimens deposited in USNM.

Remarks. Synergus oneratus was described from an unstated number of specimens ( Harris 1841: 398). We located and examined a single female belonging to the type series deposited in MCZ, which has been designated as lectotype.

Synergus oneratus coloradensis was mentioned for the first time by Gillette (1896: 91) as a variety and Burks (1979: 1062) considered it as a subspecies. We located and examined 2ϐ and 2♀ deposited in USNM with red labels reading ‘Type’, ‘Allotype’, and ‘Paratype’ respectively, as well as with a USNM accession number. Gillette did not designate a type series for this variety, so we assume that USNM recognized these specimens as the type series (syntypes) of S. oneratus coloradensis . We designate one of the examined females as lectotype and the rest of specimens as paralectotypes.

Synergus garryana was described from 5ϐ and 4♀ ( Gillette 1896: 92). We located and examined 1ϐ and 3♀ belonging to the type series deposited in USNM. A lectotype has herein been designated .

After examining the type material of both subspecies of S. oneratus ( S. oneratus oneratus and S. oneratus coloradensis ), we are confident that they must be synonymized despite showing distinct coloration patterns, since Harris himself (1841: 398) states that Synergus oneratus varies in color. On the other hand, after examining the type material of S. garryana we found no morphological differences between this species and S. oneratus , both sharing host galls and distributions. Hence, we propose here Synergus oneratus coloradensis Gillette, 1896 and Synergus garryana Gillette, 1893 as new synonyms of Synergus oneratus ( Harris, 1841) .

The host plants are not mentioned neither in the original description of S. oneratus nor in the comments given about S. oneratus coloradensis by Gillette (1896). According to Burks (1979), A. quercusstrobilana is associated with Q. bicolor and Q. macrocarpa ; A. brevipennata , with Q. x undulata , Q. gambelii , and Q. turbinella ; D. quercusglobulus , with Q. alba , Q. prinoides , and ‘ Q. prinus ’ (which could be Q. muehlenbergii or Q. montana ); and D. rubens , with Q. arizonica , Q. x undulata , Q. gambelii , ‘ Q. oblongifolia ’ (which could be Q. oblongifolia , Q. chrysolepis , or Q. grisea ), Q. rugosa , Q. turbinella , and Q. toumeyi .

Figures

FIGURE 30. Synergus oneratus. Lectotype of Cynips oneratus (MCZ-ENT 00026335): a) lateral habitus; b) detailed view of the lateral pronotum and mesoscutum; c) head and pronotum in anterodorsal view; d) dorsal habitus. Lectotype of Synergus oneratus coloradensis (USNMENT 00779991): e) lateral habitus; f) mesosoma in dorsal view. Lectotype of Synergus garryana (USNMENT 00802113): g) lateral habitus; h) detailed view of the metasomal punctuation; i) head in anterodorsal view; j) mesosoma in dorsal view.

FIGURE 37. Synergus rutulus (holotype, Type No. 5816): a) lateral habitus; b) mesosoma in dorsal view; c) head in dorsal view.