Synergus pomiformis ( Ashmead, 1885 ), 1922

Lobato-Vila, Irene, Equihua-Martínez, Armando, Estrada-Venegas, Edith G., Cibrián-Tovar, David, Barrera-Ruíz, Uriel M. & Pujade-Villar, Juli, 2020, Synergus Hartig species group (Hymenoptera: Cynipidae: Synergini) with partially smooth mesopleurae from the New World, Zootaxa 4822 (1), pp. 1-38 : 26-29

Synergus pomiformis ( Ashmead, 1885)

( Figure 5 c–d)

Ceroptres pomiformis Ashmead, 1885 . Trans. Am. Entomol. Soc. 12: 300. Type material: USNM.

Synergus flavus Kieffer, 1904 . Bull. Soc. Hist. Nat. Metz, ser. 2, 11: 133 syn. nov. Type material: USNM (lectotype), paralectotypes in USNM and CAS .

Synergus varicolor Fullaway, 1911 . Ann. Entomol. Soc. Am. 4: 371 syn. nov. Type material: USNM.

Synergus pomiformis: Weld (1922) . Proc. U. S. Nat. Mus. 61: 26.

Synergus variegatus McCracken & Egbert, 1922 . Stanford Univ., Pubs., Univ. Ser. Biol. Sci. 3 (1): 51 (in part). Type material (in part): paralectotypes in USNM.

Type material of Ceroptres pomiformis Ashmead, 1885 (examined). LECTOTYPE ♀ with the following labels: ‘Riverside, California’ (white label, handwritten) / ‘Type No. 14539 U.S. N.M’ (red label) / ‘Collection Ashmead’ (white label) / ‘ Ceroptres pomiformis Ashm. ’ (white label, handwritten) / ‘USNMENT 00802255’ (white label, QR code) / ‘ Lectotype ♀ Ceroptres pomiformis Ashmead, 1885 , IL-V desig-2017’ (red label) / ‘ Synergus pomiformis (Ashmead) Weld, 1922 , IL-V det. 2017’ (white label).

Type material of Synergus flavus Kieffer, 1904 (examined). LECTOTYPE ♀ with the following labels: ‘Claremont Cal., Baker’ (white label) / ‘ U.S. N.M. Paratype No. 25005’ (red label) / ‘USNMENT 00960403’ (white label, QR code) / ‘ Lectotype ♀ Synergus flavus Kieffer, 1904 , IL-V desig-2019’ (red label) / ‘ Synergus pomiformis (Ashmead) Weld, 1922 , IL-V det. 2019’ (white label). PARALECTOTYPES (3♀) with the following labels: ‘Claremont Cal., Baker’ (white label) / ‘ U.S. N.M. Paratype No 25005’ (red label) / ‘ Paralectotype ♀ Synergus flavus Kieffer, 1904 , IL-V desig-2019’ (red label) / ‘ Synergus pomiformis (Ashmead) Weld, 1922 , IL-V det. 2019’ (white label) (2♀); ‘Claremont, Col. Baker’ (white label) / ‘ U.S. N.M. Paratype No 25005’ (red label) / ‘ Synergus flavus Kieff. , by exch. with Panama’ (white label, handwritten)’ / ‘ Paralectotype ♀ Synergus flavus Kieffer, 1904 , IL-V desig-2019’ (red label) / ‘ Synergus pomiformis (Ashmead) Weld, 1922 , IL-V det. 2019’ (white label) (1♀). Six more specimens deposited in CAS (sex unknown, not examined) remain under the category of syntype ( R. Zuparko pers. comm.).

Type material of Synergus varicolor Fullaway, 1911 (examined). LECTOTYPE ♀ with the following labels: ‘Stanford Univ. Calif., R.W. Patterson’ (white label, handwritten) / ‘L.S.Jr.U., Lot 500, Sub 18’ (white label) / ‘Cotype’ (pink label) / ‘ Synergus varicolor Full’ (white label, handwritten) / ‘ Synergus varicolor Full’ (white label, handwritten; the same as the previous label) / ‘Beut. Coll. rec’ d1939’ (white label) / ‘USNMENT 01081309 ’ (white label, QR code) / ‘ Lectotype ♀ Synergus varicolor Fullaway, 1911 , IL-V desig-2019’ (red label) / ‘ Synergus pomiformis (Ashmead) Weld, 1922 , IL-V det. 2019’ (white label). PARALECTOTYPES (1♂ & 3♀) with the following labels: ‘Stanford Univ. Calif., R.W. Patterson’ (white label, handwritten) / ‘L.S.Jr. U., Lot 500, Sub 18’ (white label) / ‘Cotype’ (red label) / ‘ Synergus varicolor Full’ (white label, handwritten) / ‘Beut. Coll. rec’ d1939’ (white label) / ‘ Paralectotype ♀ Synergus varicolor Fullaway, 1911 , IL-V desig-2019’ (red label) / ‘ Synergus pomiformis (Ashmead) Weld, 1922 , IL-V det. 2019’ (white label) (2♀); ‘L.S.Jr. U., Lot 497, Sub 17’ (white label) / ‘PARATYPE’ (yellow label) / ‘ Paratype No. 24995 U.S. N.M’ (red label) / ‘USNMENT 00960457’ (white label, QR code) / ‘ Paralectotype ♂ Synergus varicolor Fullaway, 1911 , IL-V desig-2019’ (red label) / ‘ Synergus pomiformis (Ashmead) Weld, 1922 , IL-V det. 2019’ (white label) (1♂); ‘L.S.Jr. U., Lot 554, Sub 264’ (white label) / ‘ ♀ ’ (white label, handwritten) / ‘I. McCracken Col.’ (white label) / ‘ Paratype No. 24995 U.S. N.M’ (red label) / ‘ Paralectotype ♀ Synergus varicolor Fullaway, 1911 , IL-V desig-2019’ (red label) / ‘ Synergus pomiformis (Ashmead) Weld, 1922 , IL-V det. 2019’ (white label) (1♀).

Type material of Synergus variegatus McCracken & Egbert, 1922 (in part; examined). PARALECTOTYPES (1♂ & 2♀) with the following labels: ‘L.S.Jr.U., Lot 554, Sub 226’ (white label) / ‘ ♀ ’ (white label, handwritten) / ‘PARATYPE’ (yellow label) / ‘ Synergus variegatus Egbert’ (white label, handwritten) / ‘Beut. Coll. rec’ d1939’ (white label) / ‘ Paralectotype ♀ Synergus variegatus McCracken & Egbert, 1922 , IL-V desig-2019’ (red label) / ‘ Synergus pomiformis (Ashmead) Weld, 1922 , IL-V det. 2019’ (white label) (1♀); ‘L.S.Jr.U., Lot 554, Sub 226’ (white label) / ‘ ♀ ’ (white label, handwritten) / ‘I. McCracken col.’ (white label) / ‘PARATYPE’ (yellow label) / ‘ Paratype No. 24500 U.S. N.M’ (red label) / ‘ Paralectotype ♀ Synergus variegatus McCracken & Egbert, 1922 , IL-V desig-2019’ (red label) / ‘ Synergus pomiformis (Ashmead) Weld, 1922 , IL-V det. 2019’ (white label) (1♀); ‘L.S.Jr. U., Lot 554, Sub 226’ (white label) / ‘ ♂ ’ (white label, handwritten) / ‘I. McCracken col.’ (white label) / ‘PARATYPE’ (yellow label) / ‘Ex gall of Andricus pacificus ’ (white label, handwritten) / ‘ Paratype No 24500 U.S. N.M’ (red label) / ‘ Synergus variegatus McC. & Eg.’ (white label, handwritten) / ‘ Paralectotype ♂ Synergus variegatus McCracken & Egbert, 1922 , IL-V desig-2019’ (red label) / ‘ Synergus pomiformis (Ashmead) Weld, 1922 , IL-V det. 2019’ (white label) (1♂).

Additional material (13♂ & 22♀). Non-type material deposited in USNM with the following labels: ‘3847’ (white label, handwritten) / ‘Through C. V. Riley’ (white label) / ‘USNMENT 00960986’ (white label, QR code) (1♂); ‘Marin Co. CAL.’ (white label) / ‘Through C. V. Riley’ (white label) / ‘On Quercus wisliceni , 22’ (white label with a black frame, handwritten; number 22 in red) / ‘Ex Andricus pomiformis Bass’ (white label, handwritten) / ‘ Synergus pomiformis (Ashm) det. Weld 1923’ (1♂ and 3♀ in the same pin); ‘ 2867 Jan. 29.86’ (white label, handwritten) / ‘Through C. V. Riley’ (white label) (4♂ & 8♀); ‘Sacramento Co. CAL.’ (white label) / ‘Through C. V. Riley’ (white label) / ‘On Quercus wisliceni , 22’ (white label with a black frame, handwritten; number 22 in red) (1♀); ‘Nordhoff, CAL.’ (white label) / ‘ Q. agrifolia ’ (white label) / ‘Ex 1621’ (white label) / ‘ Synergus pomiformis (Asmh.) = flavus Kieffer = varicolor McC+Egb.’ (white label with a black frame, handwritten) (1♂ & 1♀ in the same pin); ‘1621 L. H. Weld’ (white label) / ‘Ex. gall Callirhytis pomiformis ’ (white label) / ‘ Synergus pomiformis det. Weld 37 (Ashm)’ (white label with a black frame, handwritten) (6♂ & 6♀). New material collected in Mexico (3♀) and deposited in UB with the following location data: MEX: 453 (Ordaz 2), Ejido Uruapan (B.C.), 31°37’18.001’’ N, 116°26’23.069’’ W, 202m, Ex. undescribed Amphibolips , Q. agrifolia , (19.x.2018) 10.xi.2018, S. Ordaz leg.

Diagnosis. Synergus pomiformis is similar to S. cibriani , S. citriformis , S. laeviventris , S. longimalaris and S. longiscapus (see above), but differs from all of them mainly by having the scutellar foveae large and subquadrate to ovate (absent, inconspicuous or small and shallow in these species) and the circumscutellar carinae weak and not well defined (well defined, sometimes up-turned and projected, in these species) (see the descriptions of all these species and the identification key).

Redescription. FEMALE. Length. Body length 2.0– 2.5 mm (n = 30).

Color ( Fig. 5 c–d). Yellow to yellowish brown or brown. Head yellow or dark yellow to orange, darker between ocelli in lighter specimens or frons, vertex and occiput brownish in darker specimens. Antennae yellow to orange or testaceous. Mesosoma dark yellow to chestnut or light brown, scutellum dorsally generally darker; metathorax light brown; tegulae light yellow. Metasoma yellow to rufous. Legs yellow or somewhat testaceous. Wings hyaline, veins light brown.

Head. In frontal view, about 1.2 times as wide as high, genae not expanded behind compound eyes. 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 compound eye. Anterior tentorial pits visible; pleurostomal and epistomal sulcus absent. Transfacial line about as long as height of compound eye. Toruli situated mid-height of compound eye; distance between torulus and compound eye about as long as diameter of torulus; distance between toruli shorter than diameter of toruli. Frons finely coriaceous, shiny, without punctures; frontal carinae absent. Head in dorsal view is almost 2.0 times as wide as long. Vertex finely coriaceous, shiny, without punctures. POL: OOL: LOL = 14.5: 11.5: 7 and diameter of lateral ocelli, 6. Occiput finely coriaceous, with scattered piliferous punctures.

Antennae ( Fig. 5c ). 14-segmented; filiform, not broadened apically; pubescence dense and short. Scape plus pedicel about 1.2 times as long as F1; pedicel 2.0 times as long as wide; F1 about 1.2 times as long as F2, F2 and F3 subequal, the following segments progressively shorter. Last flagellar segment about 3.0 times as long as wide and about 1.7 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. 5c ). Ratio of length of pronotum medially/laterally: 0.24. Pronotal plate indistinct. Lateral pronotum ( Fig. 5c ) finely imbricated to weakly wrinkled; lateral margins of pronotum rounded, without lateral carina. Mesoscutum ( Fig. 5d ) about 1.2 times as wide as long, coriaceous to finely imbricated, sometimes with some weak discontinuous transversal elements; anterior grooves inconspicuous. Notauli incomplete, faint in the anterior 1/3 (sometimes only visible in the distal half of the mesoscutum). Median groove absent. Parapsidal grooves inconspicuous. Scutellum ( Fig. 5d ) rounded, about as long as wide or at most 1.1 times as long as wide, medially coriaceous to finely imbricated, weakly rugose laterally and posteriorly; circumscutellar carina weak, obscured by rugae; scutellar foveae large, subquadrangular to ovate, shallow, weakly sculptured, not well defined posteriorly and separated by a narrow carina. Mesopleurae ( Fig. 5c ) regularly and separately striate medially, finely striate basally, speculum smooth; little pubescent basally. Metapleural sulcus reaching 4/5 of mesopleural height. Propodeum pubescent and weakly sculptured; propodeal carinae straight and parallel. Nucha sulcated dorsally and laterally.

Legs. Tarsal claws with a basal tooth.

Wings. Fore wings pubescent with short marginal setae, longer than body length ( Fig. 5c ). Radial cell ambiguously closed and 2.4 times as long as wide; areolet inconspicuous. Rs+M inconspicuous, not reaching the basal vein. Basal cell with sparsely spaced setae.

Metasoma. Slightly longer than head plus mesosoma, about 1.4 times as long as high in lateral view ( Fig. 5c ). First metasomal segment sulcated dorsally and laterally, with furrows sometimes reaching only half of the segment. Syntergite smooth, anterolateral pubescence composed of a few setae and without punctures (or at least with a small posterodorsal patch of micropunctures); not dorsodistally incised, 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 morphological traits: body length 1.2–1.5 mm (n = 15). Antennae 15-segmented; F1 emarginated. Lighter body color.

Distribution. USA, different localities from the state of California ( Fullaway 1911; McCracken & Egbert 1922; and in this work, see the additional material) and Mexico, state of Baja California (see the additional material).

Biology. Both Synergus pomiformis¸ S. flavus and S. varicolor were originally reared from galls of Callirhytis quercuspomiformis (Bassett, 1881) (= C. maculipennis Kieffer, 1904 ) ( Ashmead 1885; Kieffer 1904; Fullaway 1911), which are found on Quercus wislizeni A. DC. and Q. agrifolia (Lobatae section), according to Burks (1979). Some non-type specimens formally determined to S. pomiformis deposited in USNM (see the additional material) were bred from galls of C. quercuspomiformis on Q. wislizeni and Q. agrifolia as well, according to their labels. For its part, the new material collected in Mexico emerged from galls of Amphibolips sp., probably a new species, on Q. agrifolia .

Remarks. Synergus pomiformis was described from two specimens by Ashmead (1885: 300). The original description seems to refer only to males, but the only examined specimen deposited in USNM is a female. Labels indicate this female is part of the type series with no doubt, so we are of the opinion that one of the specimens mentioned by Ashmead must in fact be a female. As it is not stated in the original description, we designated as the lectotype of the type series the only examined female.

Synergus flavus was described from an unstated number of specimens ( Kieffer 1904: 133). We located and examined 4♀ belonging to the type series deposited in USNM , while six more unstudied specimens are deposited in CAS (R. Zuparko pers. comm.). The specimens at USNM are labelled as ‘Paratypes’, but Kieffer (1904) neither designated a holotype nor commented where did he deposit the type series. Hence, a lectotype for this species has been designated and deposited in USNM .

Synergus varicolor was described from an unstated number of specimens ( Fullaway 1911: 371). We located and examined 1♂ and 4♀ belonging to the type series deposited in USNM. According to McCracken & Egbert (1922: 51), the type of this species was deposited in the Stanford Entomological Museum (later absorbed by CAS), but no type material is currently deposited in this institution (R. Zuparko pers. comm). We also found an empty pin with the following labels: ‘L.S.Jr. U., Lot 497, Sub 17’ (white label) / ‘PARATYPE’ (yellow label) / ‘Ex. gall Callirh. pomiformis ’ (white label, handwritten) / ‘ Paratype No. 24995 U.S. N.M.’ (red label) / ‘ Synergus varicolor Full. ’ (white label with a red frame, handwritten); this and one of the paralectotypes have yellow ‘Paratype’ labels instead of ‘Cotype’ as most of Fullaway’s types. The term ‘Paratype’ was not used until some years after the publication of the description of S. varicolor , so we think these specimens were not labelled by Fullaway, but by a different author. Both the typology and the handwriting of these labels is the same as the one used in the species described by Mc-Cracken & Egbert (1922); so, we are of the opinion that these two authors labelled these specimens as ‘Paratypes’ probably after finding some notes written by Fullaway. Lastly, and since it is not stated in the original description, a lectotype for S. varicolor has been designated and deposited in USNM.

After examining all this type material, we conclude S. pomiformis , S. flavus and S. varicolor are the same species. According to the original descriptions of S. pomiformis and S. varicolor , females of these three species have the mesosoma more or less black or with some dark surfaces, while in S. flavus the mesosoma is yellow with less dark areas. However, all the specimens examined display a moderate degree of coloration variability. As a result, and since the rest of morphological traits are identical between them and they were bred from the same galls and collected in the same state, we do not consider coloration variability prove enough to keep considering them as different species. Hence, S. flavus and S. varicolor are here proposed as new synonyms of S. pomiformis . This synonymy had already been proposed, but not formally published, in one of the labels found among the non-type material of S. pomiformis deposited in USNM (see the additional material), probably written by L. H. Weld, according to its handwriting.

As it has been stated in the remarks section of S. flavens (see above), the type series of S. variegatus is composed of two different species. The specimens that belong to this type series that are deposited in USNM correspond to S. pomiformis . The only specimens of the type series that truly correspond to S. variegatus are those deposited in CAS.

Figures

FIGURE 5. Synergus profusus (synonym of S. pacificus): a) lateral habitus; b) dorsal view. Synergus pomiformis: c) lateral habitus; d) dorsal view. Synergus succinipedis: e) lateral habitus; f) dorsal view.