Tetramesa phragmitis ( Erdös, 1952 )

Zerova, M. D. & Fursov, V. N., 2016, A Redescription And New Data On The Distribution Of Tetramesa Phragmitis (Hymenoptera, Eurytomidae), Vestnik Zoologii 50 (1), pp. 85-88 : 86-88

Tetramesa phragmitis ( Erdös, 1952) , fig. 1 –8

References. Erdös, 1952: 117–121 (♀); 1955: 46 (Ơ) ( Gahaniola ). — Claridge, 1961: 83; Zerova, 1967:

29–37; 1976: 138; 1978: 120.

M a t e r i a l e x a m i n e d. Type. Lectotype ♀, HNHM N 4136 , Hungary, designated by Szelenyi in 1973; 6 ♀ (paralectotypes): Hungary, 11.05.1950 (Erdös), on Phragmites vulgaris Lam. (HNHM) .

Non-type. Ukraine: Kherson Region: Black Sea Reserve, Ivano-Rybalchansky, 17.05.1971 (Zerova), ex stems Phragmites communis *, exit 25.06.1971, 8.09.1971, 3 ♀, 23 Ơ (Zerova); idem, Ivano-Rybalchansky , ex stems of reeds, 25.04.1974, 14 ♀ , 1 Ơ (Zerova); idem, coll. 5.04.1971, exit 25.05.1971, 44 ♀ , 8 Ơ (Zerova); idem, coll. 5.04.1971, exit 27.05.1971, 7 ♀ , 1 Ơ (Zerova); idem, Solenoozerny , ex stems Ph. communis , coll. 25.06.1970, exit 3.09.1970, 18 Ơ (Zerova) ; idem, ex stems Ph. communis , coll. 24.04.1974, exit 20.05.1974, 27 ♀ , 4 Ơ (Zerova); Black Sea Reserve , 23.06.1976, 1 ♀ (Kotenko) ; Odessa Region: Reserve “Dunayski Plavni”, 8.07.1997, 1 ♀ (Kotenko) ; Donetsk Region: Telmanove, Reserve “Khomutovsky Step”, Ph. communis , coll. 24.04.1975, exit 16.05.1975, 33 ♀ , 3 Ơ ( Zerova ); Moldova: Chişinau, stems Ph. communis , 25.05.1972, 8 ♀ , 1 Ơ (Chiauca); Văleni , marshes, 8.06.1967, 1 ♀ (Talitsky) ; Ciumai , 17.08.1967, 2 ♀ (Talitsky) ; Russia: Stavropol Territory: Kargalinskaya , 16.05.1972, 1 ♀ (Zerova) ; Astrakhan Region: Astrakhan branch VNPO, laboratory of biological control, ex Ph. communis , 11.06.1973, 1 ♀ (Zerova) ; Astrakhan Reserve , reed, coll. 7.05.1976, exit 16.07.1976, 8 ♀ (Zerova) ; 2 Ơ, idem, coll. 7.05.1976, exit 16.07.1976 (Zerova); 1 ♀ , idem, Domchansky uch., 7.05.1976 (Zerova); Primorsky (Maritime) Territory: Reserve “Kedrovaya Pad”, from stems Ph. japonica , coll. 1.05.1983, exit 6.07.1983, 20 ♀ , 2 Ơ (Zerova); Tajikistan: Jilikul, at Vakhsh River , 13.06.1936, 1 ♀ ; idem, old dock, 22.06.1941, 1 Ơ ( V. Gussakovsky); Israel: Nahal Alexander, environs Hagera, reared from Phragmites sp. at river of Reni , 13.07.2003, 1 ♀ (Simutnik) ; Japan: Kyushu, Ibaraki Pref., Tsukuba, Sakuragaoka , swept on grass & bamboo near forest, 26.04.1997, 3 ♀ (Fursov) ; Kyushu, Fukuoka Pref., c. Kamiishigama , 12.03.1999 ( R. Matsumoto), ex Ph. japonica , 04.1999, 2 ♀ , 2 Ơ (Kamijo et Matsumoto ) ( SIZK) .

Description

Female. Length of body 2.7–4.3 mm. Body quite strong, with fairly wide mesosoma and large head. Colouration black with some bright yellow spots around clypeus, on cheeks, in some specimens around eyes, and sometimes on sides of mesothorax; tegula yellow. Yellow spots on pronotum, being typical for vast majority of Tetramesa species, are very variable in size, from small, at outer corner of pronotum, to very large, well spaced throughout lateral side of pronotum. Coxae mostly black, yellow at apex, rest of legs bright yellow. Fore wing with unclear yellow spot under marginal vein; veins yellow. Antenna brownish-yellow. Pubescence of body weakly noticeable.

Head dorsally much broader than pronotum, massive, round, no more than 1.5 × wider than long; POL 1.2–1.3 × OOL, temples very short, twice shorter than eye. Head, in frontal view, wider than its height, with ratio 52: 40; frons visibly prominent; clypeus with very weakly convex outer edge, unclearly delimited; frontal cavity deep, unclearly bordered, with subparallel edges, tapering only slightly upwards. Eye glabrous; cheek as long as longitudinal diameter of eye.

Face sculpture distinct, reticulated-cellular, with very short and sparse pubescence. Head, in lateral view, with antenna attached slightly above middle of face; scape long, not convexed, reaching level of middle of eye; flagellum relatively short, with 6 flagellomeres; 1st flagellomere longest, 1.5 × as long as wide; 2–5th flagellomeres more or less transverse, almost quadrate; clava 2-segmented, its segments clearly separated, apical processes clearly expressed; width of clava not exceeding width of flagellum; anellus very small.

Mesosoma in lateral view not convex, elongated. Propodeum slightly inclined, in dorsal view almost as long as mesoscutum. Scutellum elongate-oval, 1.8 × as long as wide medially. Sculpture of pronotum and mesonotum small-cellular, with rare, scattered, small, round spots, more distinct on scutellum. Propodeum long, tapering towards top, with a distinct deep median furrow, peripherally coarsely rugose.

Fore wing 2.6–2.7 × as long as its maximum width, with obscure black spot under marginal vein. Disc long and narrow. Marginal vein relatively short and slightly expanded; ratio of marginal and radial veins = 28: 20: 14.

Hind coxa elongate, with weak sculpture.

Metasoma elongated, severely narrowed towards top (in lateral view), with very short petiole, 1st tergite longest, almost as long as 2nd and 3rd tergites combined; 2–5th tergites of equal length; 6th tergite 1.5 × as long as 5th tergite, epipygium very short. All tergites shiny, with very small, weakly visible punctures.

Male. Length of body 3.1–3.3 mm. Coloration and sculpture as in female, but yellow spots are smaller and predominate on face and upper corners of pronotum. Antenna with 7 flagellomeres and very short diffuse pubescence. Petiole of first tergite short, at most twice longer than its width. Metasoma long, 0.5–0.65 × as long as mesosoma.

Variability: Yellow spots on head and thorax vary from relatively small to large. Specimens collected in southern territories ( Israel, Tajikistan) are lighter, sometimes almost entirely yellow.

C o m p a r a t i v e n o t e s. T. phragmitis differs from other species of the genus by the combination of following characters: fore wings with relatively short and slightly enlarged marginal vein; male metasoma with short petiolus; male antenna with very short diffuse pubescence.

Biology. Phytophagous chalcid wasp. Larvae develop inside stems of Phragmites spp. Each larva forms an individual cell at the top of cane stalks. One stalk usually contains several (up to 10 or more) cells with larvae of T. phragmitis . The importance for biological control of Phragmites was not studied.

D i s t r i b u t i o n. Trans-Palaearctic species: Central Europe ( Hungary, Czech Republic) through Moldova, Southern Ukraine, Caspian Sea region, Stavropol Territory and Kuban of Russia, Middle East, Central Asia to south of the Russian Far East (Primorsky Territory) and Japan. Abundant in southern regions of Europe. In Ukraine this species is abundant in swamps at rivers (Danube, Southern Bug, Dnieper), but was not recorded earlier in northern regions of Ukraine (but only in the north of Kherson and Donetsk Regions). Abundant in Kuban region and Stavropol Territory of Russia and in Israel along the rivers.

Authors are greatly acknowledged John Phipps, who kindly read and corrected English language of the manuscript.

Figures

Fig. 1. Tetramesa phragmitis, 1–5 — female, 6, 7 — male: 1 — antenna; 2 — fore wing venation; 3 — radial and marginal veins; 4 — adult, lateral view; 5 — adult, dorsal view; 6 — adult, lateral view; 7 — head, frontal view; 8 — infested stems of Phragmites sp. with emergence holes.