Synergus pacificus McCracken & Egbert, 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 : 24-25

Synergus pacificus McCracken & Egbert, 1922

( Figure 5 a–b)

Synergus pacificus McCracken & Egbert, 1922 . Stanford Univ., Pubs., Univ. Ser. Biol. Sci. 3 (1): 56. Type material: CAS (lectotype), paralectotypes in CAS and USNM .

Synergus profusus McCracken & Egbert, 1922 . Stanford Univ., Pubs., Univ. Ser. Biol. Sci. 3 (1): 59 syn. nov. Type material: CAS (lectotype), paralectotypes in CAS and USNM .

Type material of Synergus pacificus McCracken & Egbert, 1922 (examined). LECTOTYPE ♀ with the following labels: ‘ L.S.Jr. U., Lot. 554, Sub. 72’ (white label) / ‘ New species Apr. 1915 ’ (white label, handwritten) / ‘ ♀ ’ (white label, handwritten) / ‘ ♀ Type’ (red label) / ‘ California Academy of Sciences , Type No. 5803’ (white label) / ‘ Lectotype ♀ Synergus pacificus McCracken & Egbert, 1922 , IL-V desig-2018’ (red label). PARALECTOTYPES (2♂) deposited in CAS and USNM with the following labels: ‘ L.S.Jr. U., Lot. 554, Sub. 72’ (white label) / ‘ ♂ Type’ (red label) / ‘ Synergus pacificus McC & Eg.’ (white label with a red frame, handwritten) / ‘ California Academy of Sciences , Type No. 5803’ (white label) / ‘ Paralectotype ♂ Synergus pacificus McCracken & Egbert, 1922 , IL-V desig-2018’ (red label) (1♂); ‘L.S.Jr.U., Lot. 554, Sub. 72’ (white label) / ‘ ♂ ’ (white label, handwritten) / ‘Paratype’ (yellow label) / ‘Beut. Coll. rec’d1939’ (white label) / ‘ Synergus pacificus Egbert’ (white label, handwritten) / ‘ Paratype No. 53993, U.S. N.M.’ (red label) / ‘ Synergus pacificus Mc +Egb.’ (white label with a black frame, handwritten) / ‘USNMENT 00960963’ (white label, QR code) / ‘ Paralectotype ♂ Synergus pacificus McCracken & Egbert, 1922 , IL-V desig-2017’ (red label) (1♂).

Type material of Synergus profusus McCracken & Egbert, 1922 . LECTOTYPE ♀ (examined) with the following labels: ‘L.S.Jr.U., Lot. 554, Sub. 23’ (white label) / ‘ ♀ Type’ (red label) / ‘ California Academy of Sciences, Type No. 5807’ (white label) / ‘ Lectotype ♀ Synergus profusus McCracken & Egbert, 1922 , IL-V desig-2019’ (red label) / ‘ Synergus pacificus McCracken & Egbert, 1922 , IL-V det. 2019’ (white label). PARALECTOTYPES (5♂ & 5♀) deposited in CAS (1♂) and USNM (4♂ & 5♀) (examined) with the following labels: ‘L.S.Jr.U., Lot. 554, Sub. 23’ (white label) / ‘ ♂ Type’ (red label) / ‘ Synergus profusus McC & Eg.’ (white label with a red frame, handwritten) / ‘ California Academy of Sciences, Type No. 5807’ (white label) / ‘ Paralectotype ♂ Synergus profusus McCracken & Egbert, 1922 , IL-V desig-2019’ (red label) / ‘ Synergus pacificus McCracken & Egbert, 1922 , IL-V det. 2019’ (white label) (1♂); ‘L.S.Jr.U., Lot. 554, Sub. 23’ (white label) / ‘I. McCracken Col.’ (white label) / ‘Paratype’ (yellow label) / ‘Ex. gall of Cynips canescens ’ (white label, handwritten) / ‘ Paratype No. 24501’ (red label) / ‘ Synergus profusus McC & Eg.’ (white label with a red frame, handwritten) / ‘ Paralectotype Synergus profusus McCracken & Egbert, 1922 , IL-V desig-2019’ (red label) / ‘ Synergus pacificus McCracken & Egbert, 1922 , IL-V det. 2019’ (white label) (2♂ & 2♀); ‘StanU, Cal., Mar 1915 ’ / ‘L.S.Jr.U. Lot. 554, Sub. 23’ (white label) / ‘Paratype’ (yellow label) / ‘ Synergus profusus Egbert’ (white label, handwritten) / ‘Beut. Coll., rec’d1939’ (white label) / ‘ Paralectotype Synergus profusus McCracken & Egbert, 1922 , IL-V desig-2019’ (red label) / ‘ Synergus pacificus McCracken & Egbert, 1922 , IL-V det. 2019’ (white label) (2♂ & 3♀). Fifty-three more specimens deposited in CAS (sex unknown, not examined) remain under the category of syntype ( R. Zuparko pers. comm.).

Diagnosis. Synergus pacificus is morphologically close to S. flavens (see above), whose main differences have already been commented on (see the diagnosis of S. flavens and the identification key).

Redescription. FEMALE. Length. Body length 2.0–3.0 mm (n = 7).

Color ( Fig. 5 a–b). Dark reddish brown to black. Head brownish, lower face and ocellar area darker, genae lighter; a somewhat light halo around the oral fovea. Antennae yellow. Mesosoma dark brown to black; tegulae yellow. Metasoma dark reddish-brown. Legs yellow, coxae darker, especially metacoxae. Wings hyaline, veins yellow.

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 clearly shorter than diameter of torulus; distance between toruli shorter than diameter of toruli. Frons finely coriaceous, without punctures; frontal carinae narrow, not reaching lateral ocelli, almost inconspicuous. Head in dorsal view is about 2.1 times as wide as long. Vertex finely coriaceous, with scarce small piliferous punctures. POL: OOL: LOL = 6: 4: 2.5 and diameter of lateral ocelli, 3. Occiput finely coriaceous, with scarce small piliferous punctures.

Antennae ( Fig. 5a ). 14-segmented; filiform, not broadened apically; pubescence dense and short. Scape plus pedicel about as long as F1; pedicel 1.5 times as long as wide; F1 about as long as F2 or at most 1.1 times as long as F2, F2 and F3 subequal, the following segments progressively shorter. Last flagellar segment almost 3.3 times as long as wide and almost 2.0 times as long as F11.

Mesosoma. About 1.3 times as long as high in lateral view, including nucha, with short and not dense pubescence ( Fig. 5a ). Ratio of length of pronotum medially/laterally: 0.45. Pronotal plate indistinct. Lateral pronotum ( Fig. 5a ) strongly coriaceous dorsally, weakly carinated basally; lateral margins of pronotum rounded, without lateral carina. Mesoscutum ( Fig. 5b ) about 1.1 times as wide as long, strongly coriaceous to weakly discontinuously carinated or with weak discontinuous transversal elements, interspaces coriaceous; anterior grooves weakly impressed, reaching at most 1/3 of the mesoscutum length. Notauli incomplete, faint in the anterior 1/3, somewhat interrupted by carinae. Median groove absent. Parapsidal grooves weakly impressed, reaching tegulae. Scutellum ( Fig. 5b ) rounded, about as long as wide, strongly wrinkled, interspaces alutaceous; circumscutellar carina weak, obscured by wrinkles; scutellar foveae ovate to subtriangular, shallow, weakly sculptured, not well defined posteriorly and separated by a narrow carina. Mesopleurae ( Fig. 5a ) basally and medially regularly striate, speculum smooth; little pubescent basally. Metapleural sulcus reaching 3/4 of mesopleural height. Propodeum pubescent and weakly sculptured; propodeal carinae very slightly curved but parallel. Nucha sulcated dorsally and laterally.

Legs. Tarsal claws with a basal tooth.

Wings. Fore wings pubescent with short marginal setae, about as long as body length ( Fig. 5a ). Radial cell closed and 2.4 times as long as wide; areolet visible, posterior vein more pigmented, the rest inconspicuous. Rs+M inconspicuous, not reaching the basal vein. Basal cell with sparsely spaced setae.

Metasoma. Slightly longer than head plus mesosoma, about 1.2 times as long as high in lateral view ( Fig. 5a ). First metasomal segment sulcated dorsally and laterally. Syntergite smooth, anterolateral pubescence composed of a very few setae and posteriorly with a band of micropunctures extending about 1/3 of the syntergite length, less extended dorsally; not 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 morphological traits: body length about 2.0 mm (n = 7). Antennae 15-segmented; F1 strongly excavated and strongly expanded apically; last flagellar segment 1.3 times as long as F12 and 2.5 times as long as wide. POL: OOL: LOL = 6.5: 3: 2.5. Malar space 0.5 times as long as height of compound eye. Mesopleurae slightly coriaceous anteriorly. Metasoma shorter than head plus mesosoma, punctures extending 1/3 of the syntergite length. Head yellow, except for a dark spot in the ocellar area.

Distribution. USA. Different localities from the state of California ( McCracken & Egbert 1922).

Biology. Synergus pacificus was reared from galls of Heteroecus pacificus ( Ashmead, 1896) on Quercus chrysolepis ( Protobalanus section), while S. profusus was reared from galls of Disholcaspis canescens (Bassett, 1890) on Q. douglasii Hook. & Arn. ( Quercus section) ( McCracken & Egbert 1922).

Remarks. Synergus pacificus was described from 5♂ and 1♀ ( McCracken & Egbert 1922: 57) and S. profusus , from 24♂ and 40♀ ( McCracken & Egbert 1922: 60). We located and examined 2♂ and 1♀ of S. pacificus (1♂ and 1♀ with a ‘Type’ label deposited in CAS, and 1♂ deposited in USNM) and 5♂ and 6♀ of S. profusus (1♂ and 1♀ with a ‘Type’ label deposited in CAS, and 4♂ and 5♀ deposited in USNM, while fifty-three unstudied specimens are deposited in CAS (R. Zuparko pers. comm.)) belonging to the type series of each species.

The authors comment that the ‘Type’ of these species was deposited at the Stanford Entomological Museum, later absorbed by CAS; however, in the ‘Type’ section they do not specify anything else but the type depository. As a result, and since the descriptors did not designate a holotype, a lectotype for each species has been designated and deposited in CAS .

After examining these two species, we found no significate morphological differences to keep considering them as different species. As a result, we propose S. profusus as a new synonym of S. pacificus .

According to the original descriptions, the specimens of both S. pacificus and S. profusus are black except for some yellowish areas, but the examined specimens go from dark brown to black with some reddish-brown areas. Since the rest of morphological traits are coincident with those of the original descriptions, we think this color differences may be the result of a discoloring process.

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.