Macroglenes gramineus (Haliday)

Mitroiu, Mircea-Dan, 2010, Revision of the Palearctic species of Macroglenes Westwood (Hymenoptera: Pteromalidae), Zootaxa 2563, pp. 1-34 : 18-19

Macroglenes gramineus (Haliday)

(Figs. 5–6, 14)

Pirene graminea Haliday, 1833: 338 .

Macroglenes gramineus ; Morley, 1910: 27.

Diagnosis. Body with no or only slight metallic reflections, mainly bronze; clypeal margin not incised (cf. Figs 1–2); antenna (Figs 5–6), with only F5 large and provided with sensilla and F1–F3 compacted together, sometimes almost fused; mesosoma moderately convex (cf. Fig. 10); pecten regular, usually 2/3 length of hind tibia (Fig. 14); forewing with bare area between R and apical margin, basal cell occasionally with few hairs near basal vein (cf. Fig. 22, but bare area less extended); ovipositor sheaths less than half length of hind tibia; tip of hypopygium not reaching tip of gaster (cf. Fig. 31). Male with eyes enlarged (cf. Fig. 2, but sometimes somewhat smaller, not always touching posterior ocelli), normal scape, and pecten occupying entire tibial length (cf. Fig. 16).

Material examined. CZECH REPUBLIC: 2Ψ ‘ Bohemia: Týništĕ n. Orl., obora. Bouček / 5. 7. 59 ’, ‘Macrogl. near? microcerus Hal. ’ ( NMPC); 1Ψ ‘Hostomice pod Brdy, BOHEMIA, Bouček 1959 / 7. 6. 59 ’ ( NMPC); 2Ψ ‘Ratibořické hory, Tábor., BOHEMIA, 14. 7. 45. Hoffer’ ( NMPC); 1Ψ, 1ɗ ‘ Bohemia c.: Praha, okolí, Bouček’, ‘Chuchle, 24. VI. 55 ’ ( NMPC); 4Ψ ‘Boh. or. Holovousy, Hostounský / 12. VII. 53 ’ ( NMPC); 6Ψ ‘Bohem. merid. Střibr. Hutĕ, 10 / VII. 1945, Bouček leg.’ ( NMPC); 1Ψ ‘ Bohemia: Týništĕ n. Orl. obora. Bouček / 5. 7. 59 ’ ( NMPC); 1Ψ ‘Bor u Skutče n/s. Bohemia, VII. 65 Macek’ ( NMPC); 1ɗ ‘Bohem. Hr. Kr., Vëkoše, Bouček / 27. VII. 47 ’ ( NMPC); 11ɗ ‘ Bohemia or., Velký Vřeštov, Bouček 9. 7. 54 ’ ( NMPC); 1ɗ idem, ‘ VIII. 53 ’ ( NMPC). GREECE: 2ɗ ’GR: Kerkini Lake Nat. Park, Kerkini Mts. nr. Neo Petritsi’, ’sweep net, 420–750 m alt., 17. VI. 2008 leg. Fusu & Popovici’, ’ Macroglenes gramineus ɗ det. M. Mitroiu ’09’ ( MICO); 1ɗ idem, ’Malaise trap, 18–22. VI. 2008 ’ ( MICO). ROMANIA: 1Ψ ‘ Macroglenes gramineus Ψ det. M. Mitroiu 2005’, ‘Barnova (IS), 2. 0 7. 1998 leg. M.M. 295’ ( MICO); 1Ψ ‘RO: IS, Barnova, 2. VII. 1999 leg. M.-D. Mitroiu’, ‘ Macroglenes gramineus Ψ det. M. Mitroiu 2009’ ( MICO); 1ɗ idem, ’ 25. VI. 2005 leg. O. Popovici’ ( MICO); 1Ψ ’ Macroglenes gramineus Ψ det. M. Mitroiu 2005’, ’Valea lui David, 11. VI. 99 leg. L. Fusu 277’ ( MICO); 5Ψ, 1ɗ ’RO: IS, Barnova - R.N. Poiana cu Schit, 21. VI. 0 7 leg. O. Popovici’, ’ Macroglenes gramineus det. M. Mitroiu 2009’ ( MICO); 1ɗ ’ Macroglenes gramineus ɗ det. M. Mitroiu 2005’, ’Potoci (NT), 26. VI. 1999, 288’ ( MICO). SLOVAKIA: 1Ψ, 1ɗ ‘ SLOVAKIA or. Somotor, leg. Kocourek / 25. 6. 52 ’ ( NMPC). SWEDEN: 1Ψ ‘ Pirene graminea Hal., Ch. Ferriere det’, ‘S. Sweden 1936, E. Johansten, Ex. Contarinia tritici Kirby. ’, ‘Pres. by Imp. Inst. Ent. B. M. 1936-780’ ( BMNH).? U.K.: 1ɗ ‘Walker coll. 1904-120’ ( BMNH).

Variation. The tibial pecten of females covers 2/3−3/4 the length of hind tibia (Fig. 14). Males are rather variable regarding eye dimensions and degree of fusion between F1–F3. Moreover, some individuals, close to the second group defined by Graham [p. 347], appear to have intermediate characters between M. gramineus and M. microcerus . However, I hesitate in considering the two names as synonymous, at least until some females with characteristic antennae, i.e. with segments F1–F3 distinctly separated, are discovered. In one of the examined males F4 was intermediate in size between F3 and F5, but without visible sensilla.

Comments. Graham (1969) stated that we may be dealing with an aggregate of species based on the variable characters of males [p. 347]. Indeed, in most individuals the eyes virtually touch the posterior ocelli (cf. Fig. 2), but in others they don’t. However, no other characters could be found to separate the two groups, thus I regard them as a single species until further evidence.

Distribution. Germany, Hungary, Ireland, Netherlands, the Republic of Moldavia, Romania, Spain, Sweden, Switzerland, U.K. ( Noyes 2003); previously not recorded from the Czech Republic, Greece and Slovakia.

Hosts. Graham (1969) mentioned that Kutter’s specimens reared in Switzerland as M. gramineus from Contarinia pisi are in fact M. chalybeus ; after examining these specimens (deposited in MHNG) I can confirm this statement. Also Graham examined some Macroglenes reared in Sweden from C. tritici , identified as M. chalybeus , which proved to be a mixture of species, “only part of which represent the true chalybea ” [p. 350]; however, he did not mention what the other species was and he did not mention C. tritici as host of M. gramineus . I found a female from this series in BMNH which belongs to M. gramineus (see above), thus this is the first published association between this species and C. tritici .