Synergus formosanus Schwéger & Melika, 2015

Schwéger, Szabina, Melika, George, Tang, Chang-Ti, Bihari, Péter, Bozsó, Miklós, Stone, Graham N., Nicholls, James A. & Pénzes, Zsolt, 2015, New species of cynipid inquilines of the genus Synergus (Hymenoptera: Cynipidae: Synergini) from the Eastern Palaearctic, Zootaxa 3999 (4), pp. 451-497 : 469-472

Synergus formosanus Schwéger & Melika , new species

Figs 43–57

Type material. HOLOTYPE female: TAIWAN (TW389), Nantou County, Cing Jing Veterans Farm, ex Trichagalma formosana asex gall on Quercus variabilis 24.X.2008. leg J. Nicholls. 59 female and 30 male PARATYPES: 25 female and 11 male: TAIWAN (TW389, TW364, TW393, TW361, TW357, TW351, TW350, TW352) Nantou County, Cing Jing Veterans Farm, ex Trichagalma formosana asex gall on Quercus variabilis 24.X.2008. leg J. Nicholls; 33 female and 18 male: TAIWAN (TW198, TW190, TW193, TW188, TW192, TW194, TW197, TW191, TW189) Nantou County, Huisun Forest Station, ex Trichagalma formosana asex gall on Quercus variabilis 25.X.2008. leg J. Nicholls; 1 female and 1 male: TAIWAN (TW339) Nantou County, 5 km East of Jenai, ex Trichagalma formosana asex gall on Quercus variabilis 23.X.2008. leg J. Nicholls.

The female holotype, 34 female and 10 male paratypes are deposited in PHMB, 10 female and 10 male paratypes in USNM and 15 female and 10 male paratypes in NCHU.

Other material examined. 10 females and 5 males: TAIWAN, Taichung Co, 29K, Central-Cross-Island Highway, Heping Township, ex. asexual Trichagalma formosana gall on Quercus variabilis , 17.X.2009., 24°10’35.40”N, 120°58’31.48”E, 685m, em. 26-IX-2009, leg. Chang-Ti Tang; 6 females and 1 male: TAIWAN, Taichung Co, 29K, Central-Cross-Island Highway, Heping Township, ex. asexual Trichagalma formosana gall on Quercus variabilis , 17.X.2009., 24°12’33.66”N, 121°01’09.98”E, 843m, em. 27-IX-2009, leg. Chang-Ti Tang; 6 females: TAIWAN, Taichung Co, 29K, Central-Cross-Island Highway, Heping Township, ex. asexual Trichagalma formosana gall on Quercus variabilis , 12.XII.2010. (TWT453) 24°10’35.40”N, 120°58’31.48”E, 685m, em. 16-I- 2011, leg. Chang-Ti Tang; 3 females: TAIWAN, Taichung Co, 29K, Central-Cross-Island Highway, Heping Township, ex. asexual Trichagalma formosana gall on Quercus variabilis , 12.XII.2010. (TWT453) 24°10’35.40”N, 120°58’31.48”E, 685m, em. 23-I-2011, leg. Chang-Ti Tang; 1 female and 6 males: TAIWAN, Taichung Co, 29K, Central-Cross-Island Highway, Heping Township, ex. asexual Trichagalma formosana gall on Quercus variabilis , 12.XII.2010. (TWT453) 24°10’35.40”N, 120°58’31.48”E, 685m, em. 12-I-2011, leg. Chang-Ti Tang.

Etymology. The species is named after the main host, Trichagalma formosana Melika & Tang (Cynipini) , from whose galls the adults of the new species were reared.

Diagnosis. Most closely resembles S. chinensis and S. formosanus . In S. chinensis the head and mesosoma are always reddish brown ( Figs 123–127 , 130–132 ), while in S. symbioticus and S. formosanus only the head is reddish brown, while the mesosoma always black or very dark brown ( Figs 107–113 , 117–120 ). In S. symbioticus the postgena with dense setae, especially along the hypostoma ( Fig. 109 ), F 1 in male curved and expanded apically ( Fig. 115 ), the median mesoscutal line is strongly impressed, complete, reaches pronotum ( Fig. 119 ), the mesoscutellum 1.4 times as long as broad ( Fig. 120 ), while in S. formosanus the postgena without setae ( Figs 45, 49 ), F 1 in male curved but not expanded apically ( Fig. 51 ), the median mesoscutal line is deeply impressed in the posterior half, extending to 2/3 of the mesoscutum, never complete ( Fig. 54 ), the mesoscutellum only slightly longer than broad ( Fig. 55 ).

Description. FEMALE. Head chestnut brown with darker frons and vertex; mesosoma black to dark brown; antenna light brown, mouthparts, maxillar and labial palps yellowish; legs yellowish brown with darker coxae; wings with yellow venation; 1st metasomal tergite always dark brown, rest of metasoma reddish brown, dorsally always darker.

Head coriaceous, nearly rounded in frontal view, 1.2 times as broad as high, slightly broader than mesosoma, 2.2 times as broad as long in dorsal view. Lower face, malar space, clypeus and gena behind eye with dense white setae, row of setae present along inner margin of eye, postgena without setae; posterior areas aside hypostoma with dense setae. Eye 1.6 times as high as length of malar space. Malar sulcus absent, strong striae radiating from clypeus and reaching eye and toruli. Clypeus very small, smoothly joins central area of lower face, with striae, slightly impressed, ventrally straight, not emarginate; epistomal sulcus and clypeo-pleurostomal line indistinct, anterior tentorial pit small, indistinct. Lower face with distinct numerous striae radiating from clypeus and extending to lower level of toruli and eyes, central part with strong complete striae extending from clypeus to antennal toruli. Frons delicately coriaceous aside of strong complete frontal carinae, with numerous deep punctures between frontal carinae; interocellar area with numerous small punctures. Transfacial distance same length as height of eye; distance between inner margin of eye and torulus slightly shorter than diameter of torulus; diameter of torulus 1.5 as long as distance between toruli. POL 2.9 times as long as OOL and 2.2 times as long as LOL; length of lateral ocellus 1.2 times as long as OOL. Vertex dull rugose, with distinct, numerous, deep punctures, with dense white setae. Occiput smooth. Gena not broadened behind eye in frontal view, coriaceous, with some white setae. Postgena smooth, without setae. Postgenal bridge reduced to long, narrow median strip; postgenal sulci united well before reaching hypostoma; posterior tentorial pit distinct, area around occipital foramen wellimpressed, smooth, shiny. Antenna with 12 flagellomeres, pedicel 1.5 times as long as broad, F1 1.2 times as long as F2 and 2.3 times as long as pedicel; F2=F3, F12 1.8 times as long as F11; placoid sensillae on F3–F12, invisible on F1–F2.

Mesosoma 1.25 times as long as high in lateral view. Sides of pronotum sharply angled in dorsal view; pronotum coriaceous, laterally with some strong short interrupted rugae, area between them weakly coriaceous or almost smooth. Propleuron alutaceous with some transverse striae and short white setae in lower half. Mesoscutum nearly as long as broad measuring along anterior edge of tegulae, with white setae; uniformly dull rugose, with short interrupted transverse rugae, especially between notauli. Notaulus complete, reaching pronotum, slightly broadened posteriory, with smooth bottom. Anterior parallel line indistinct, hardly traceable. Parapsidal line narrow, smooth, extending to half length of mesoscutum; distinct parascutal carina present, reaches pronotum; median mesoscutal line deeply impressed in posterior half, extending to 2/3 of mesoscutum, never complete. Dorsoaxillar area very finely coriaceous, with micropunctures; lateroaxillar area joins dorsoaxillar area at acute angle. Mesoscutellum slightly longer than broad, uniformly dull rugose. Scutellar foveae transverse, deeply impressed, with delicately coriaceous bottom, separated by distinct narrow central carina, well delimited posteriorly. Mesopectus with transverse parallel longitudinal striae, with smooth area between stiae. Metapleural sulcus reaches posterior margin of mesopectus in most upper 1/3 of its height. Propodeum smooth, glabrous, with sparse short white setae laterally and dorsally; lateral propodeal carinae distinct, uniformly thin, nearly straight; central propodeal area delicately coriaceous, with some striae, without setae. Metascutellum smooth, shorter than smooth ventral impressed area; metanotal trough smooth, without setae; propodeal spiracle transversely ovate, with strong raised carina along anterior border. Nucha black, with longitudinal parallel rugae dorsally and laterally.

Fore wing veins pale, yellowish; margin with long cilia; radial cell opened, 2.6–2.8 times as long as broad; Rs and R1 slightly curved, areolet present. Legs with short white setae, tarsal claws with distinct basal lobe.

Metasoma only very slightly longer than head+mesosoma and slightly longer than high in lateral view. First metasomal tergite with longitudinal parallel rugae dorsally and laterally. Syntergite with few white setae anterolaterally, smooth, glabrous; posterodorsally slightly incised, with small rounded dorsoposterior patch of delicate micropunctures which not extending onto lateral sides. Subsequent tergites and hypopygium micropunctate; prominent part of ventral spine of hypopygium short with very few short white setae ventrally. Body length 2.4–2.9 mm (n =15).

MALE. Similar to female but head more rounded in frontal view and yellowish brown with only darker frons; antenna with 13 flagellomeres, F1 slightly curved and broadened apically, less broadened basally, 1.6 times as long as F2; placoid sensillae on F3–F11. Body length 2.2–2.6 mm (n = 15).

Biology. This species was reared only from the asexual galls of Trichagalma formosana Melika & Tang ( Fig. 148 ) on Quercus variabilis Blume , adults emerged under laboratory conditions during October.

Distribution. Currently known from Taiwan only (Nantou county).

Figures

FIGURES 43 – 51. Synergus formosanus, new species, 43 – 46, head, female: 43, frontal view, 44, dorsal view, 45, posterior view, 46, lateral view, 47 – 49, head, male: 47, frontal view, 48, dorsal view, 49, posterior view. 50 – 51, antenna: 50, female, 51, male.

FIGURES 52 – 57. Synergus formosanus, new species, female: 52, pronotum and propleuron, frontal view, 53, mesosoma, lateral view, 54, mesoscutum, dorsal view, 55, mesoscutellum, dorsal view, 56, metascutellum and propodeum, posterodorsal view, 57, metasoma, lateral view.

FIGURES 123 – 129. Synergus chinensis, 123 – 125, head, female: 123, frontal view, 124, dorsal view, 125, posterior view. 126 – 127, head, male: 126, frontal view, 127, dorsal view. 128 – 129, antenna: 128, female, 129, male.

FIGURES 130 – 133. Synergus chinensis, female: 130, pronotum and propleuron, frontal view, 131, mesosoma, lateral view, 132, mesoscutum and metascutellum, dorsal view, 133, metasoma, part, lateral view.

FIGURES 107 – 116. Synergus symbioticus, new species, 107 – 110, head, female: 107, frontal view, 108, dorsal view, 109, posterior view, 110, lateral view. 111 – 113, head, male: 111, frontal view, 112, dorsal view, 113, posterior view. 114 – 115, antenna: 114, female, 115, male. 116, hind tarsal claw.

FIGURES 117 – 122. Synergus symbioticus, new species, 117 – 120, female: 117, pronotum and propleuron, frontal view, 118, mesosoma, lateral view, 119, mesoscutum, dorsal view, 120, mesoscutellum, dorsal view. 121 – 122, metasoma, lateral view: 121, female, 122, male.

FIGURES 145 – 157. Host oak galls of newly described Synergus spp.: 145, Andricus kashiwaphilus, asexual gall, 146, A. mukaigawae, asexual gall, 147, A. hakonensis (= A. symbioticus), asexual galls, 148, Trichagalma formosana, asexual galls, 149, Belizinella sp., asexual gall, 150, Ussuraspis sp., asexual gall, 151, undescribed leaf gall (RUl 5), 152, undescribed leaf gall (RUl 1), 153, undescribed acorn gall (JPa 2), 154, undescribed bud gall (JPb 1), 155, undescribed bud gall (JPb 1), 156, undescribed acorn gall (JPa 1) (photos by G. Csóka). 157, undescribed stem swelling-like gall (TWTs 13) (photos by Chang Ti Tang).