Notes on Macromesug Walk. (Hym. Chalcidoidea, Pteromalidae) and description of a new species
By
IiaRL-JoHAN HEevrsr
\Yhen rvorking on chalcids as parasites of brrk-beetles I received speci- mens of :r remarkable species from F-inland. After seeking in lhe literature I for.rnd that lhe specimens belonged lo lltesenbergia occura( Iiryg. The genus lltesertberg t f,ry61. was described by Kryger in year 1943 and the species was clplured by him in a \r'et mendow along an acclivit5r \yith spruces- \orth
Sealand. Denmark. In )'ear 1959 \I.\\'. R. de \'. Graham published a redescrip- tion of .l/ncromesrrs ompiirclus \\'erlk. Cornparing my specimens with his exellent description I found that they agree yery rvell. It is obvious lhat ll'esettbergiu Iirvg. is congeneric rvith -Jlacronresus \\'alk. lnd consequentlv s]'nonvul()us rvitlr the latter geDus. 'Ihe nerv svuonvnrl' is given as follorvs:
,llrucronresrrs Nalk. I E{E
ll'esenbergtu liryg. 1.943 syn. nov.
fl qcronrcsus entphirctus \Yalk. l8-18
ll'estrrbergfu occrrllo Kr1'9. l9-13 s1'n. nov.
flucronrcsus entphiretus \Yalk. is now knorvn from Engl:rnd. F-inland.
Polaud and Srveden. In Sweden I huve bred this species from a bnrk-beelle.
P hl horophloe us spinrrlosrrs Rer'-
In a lrox n-ith material of Trigonoderus and Epi.slenirr I got fram Snrith- rionian Institution. \Yashington. U.S.-{.. there $'ere m nv specimens of a spe- cies rvlrich to mv surprise belonged to .llocrorrresus \\'tlk. -\ descriptiorr of this nerv species is iJiven belorv.
Macromesue americsnut sp.n.
9. Head blue-r'iolet \yith melallic luslre, face liolet.'I'horas dorsalll' bronze- i{reelr. laterall}' blue. -\bdomen dark brorvn. .{nlennire rvith scape 1'ellorv.
pedicellus 1'elloish brou'n. :lnellus. funicle segments rrrd clava dark brorrn.
Fore-. nrid- and lrindlegs reddish 1'ellorv. Hind cosa basally blue with rnelal-
lic lustre. -{ll fenrora and tibia Nith tiul of brorvn. \\'ing leins light brortn.
Head subglobular. \Ial:rr ilroore slrong. belNeerr antennal sockel aud malar groole a supplenrenlar]' groor-e rvhich runs nearll- purallel \\ith the millilr groovc but not renching the base of mandible. F-ace arr<l vertex rvilh scattered small punctures lNith hairs). The et'es o\.ale. lari.ie. \lnndibles iright and
E ontn. Ts. ,1",.81. ll.1-1.1960
lll0l
NOTES ON }IACRO\TESUS $'ALK. AND DESCRIPTION OT'A NE\T'SPECTES I4I
I.ig. 1 l. Forc$'ing of.]/dcronesus dnrpli..lus \Yalk B. Forr,\ing of Jracrompsus arrerirnnus sp.n.
left) lYith 3 teeth. Clypeus anterior margin lruncale. above lhe clypeus l\yo pits. .{ntennae inserted slightly belon' leYel of ventral edge of e)'es. r'ith for- mula 11172. Scape short, pedicellus shorter than the first funicle segment.
firnicle segments longer than broad. the first funicle se€iment longest. (:lava not storrler than flagellum. The rvhole head fine reticulated, round itbttrrt rrrirlar grooves Yery fine.
Pronotun short and rounded. The middle lobe of nresoscuturn slightll' shorler than scutellun. Notaulices complete and deep. converging slrongly lowards scutellum. )Ietascutellum large, with puncturation similar rvith the remaining part of thora\. Propodeum slightl-rr decliyed rvith nredian carina.
plica only posteriorly indicated. spiracles subcircular and fimbriae ferv.
-{ll femora slout. I.ore corae nearly as long as the lrind coxae. I}orc- rrtd hind coxae above with row of hairs (fig. 2. E.). Fore- and hiud tibia rvith a
row of spines. Mid tarsus; lhe first segment louger than the rest. Hilld tibia rvith a singel spur.
l'orewing (lii{. l. B.) with mar5Jinal vein shorter than lhe poslmarginal Yein but longer than the stigmal. Stigma not distinctly separated fronr the sligmal vein aud not so large. Basalcell with hairs, speculum postbaslrle large.
Gaster lanceolarte.
C. Resembles the female. brrl has. horvever, anlennae l3-segmented lt I173) and funicle segments more fusiform. Gaster oblong.
-llrucrorncsrr.s antericttnus sp.n. is very similar to the European species )1. umphiretus \\'alk.. and lhe following key will serre lo distinguish lhe nen' species from the European one.
)rt. Rl- ll.3-l- llrin I
r {2 K.\ItL-JOHAN HEQ\'IST
A B
'{#
C D
E
Fig. 2. A. .lr.rcromesus amphirctus \Yalk-, head in dorsal rierv., B. .llocromesus ometicanus sp.n.. head in dorsal \,ie$'., C. -l/dc.omesur omphiritu$ lYalk., the reliculation on meso- scuIum., D. .l/rrcroraesus orne?icanus sp.n., the reticulalion on mesosculum., E. illacromesus
americanus sp.n.. the fore coxa.
I. ]Ietuscutellum has stronger reticulation than sculellum and scutum. Postmarginal vein shorter than the marginal rein. Stigma large. Basalcell $ith a line of verl' small hairs (fig. 1..{.). Mandibles Nith 2 slightly pointed teeth aod a third (inner) obtuse one. llarginal fringe lfig. 1..{.) going around the apex of the foreNing.
.v. ortpiirettrs \Yalk.
-. Iletascutellum has not slronger reticulation than sculellumi reticulation similar over the \yhole thorax and a large part of head. The postnrarginal vein (fig. l. B.i longer than the marginal vein. Stigma (fig. l.B.) moderatel]' large and nol distinctly separated from the stigmal vein. Basalcell (fig. l. B. ) \\ ith both large and small hairs. \Iandibles Nith 3 teeth, rhe rhird (inner) nol obtuse. trtarginal fringc (fig. 1. B.) not going around the apex of the forerving ... M. flmeaiconlls sp.n.
'Ihere are also some differences in the colour.
]laterial: )!. untphiretus \\'alk. { 99 and 2 d d.
)1. umericunus sp.n. l{ 9? and I dd.
Holotype: Dragon llls. .{riz. Cochire Strngh, .{pril 23,1957, Arizona C;-press, leg. G. lluller and F. \\'erner.
.\llotype: The same locality' as for the holotype.
Paratype: 3 99 and I d fron the same locality as above.
I 9 and I d Lodgepole Pine above Suttle lk., Oreg., 6-21-39, hosts:
Cg lind roco pt urus longrrlus (Lec.).
Enlomol. Ts- lut.8t- ll. 3-1.19e0
NOTES ON IIACROMESTIS vr'ALI(. AND DESCRIPTION OF A NE\\'SPECIES 143
I I (Hopk. U.S. 37558) Middtetown, Lake Co., Calit., XI-l l-l9.il, leg.
G. M. 'Ihomson.
3 9? and 3 6 6 1Hopk. U.S. 31068), Colfax, Cal., l-31-51, Pseudotsuga
tarilolia, leg. G. C. Trostle.
3 99 and 3 66 (Hopk. U.S.21083.2 specimens I 9 and I d are marked rvith 85,3 specimens 2 99 and I 3 with 82 and I specimen I d with
B 7) Pine Crest Calif., 6-21-34, Pittus krmbertinnn, Pinus pontlerosa.
l-eg. K. .{. Salman and J. M. }Iillcr.
I Y (Hopk. U.S. 33751) B) Placerville, Cal., Eldorado Co., X-l 1946,
Pinus nontarut, Ieg. J. M. Ililler.
19 rHopk. U.S.31906e) Yoscmite Nat. Pk., VI-ll-1956, .lbies concolor, leg. G. R. Struble.
Litcrsture
GR-a.rr^rr, f[. W. R. de \'.: Rediscover.'" of .lfncromerus amphirelus \Yalk. (Hym.. Chatci- doidea, Pteromalidae) in Britsin, $ilh a discussion of ils s!'stemalic position. Ent.
llonthll Vag. Vol. XCVi pp. 7&-7E, 1959.
KRycER, J. P.: T$-o notes on Chalcid Flies.
- Ent. lledd. Bend \XlI, pp. 361)--363. Copen- hagen l9{3.
\Y^LrER, F-.: Lisl of the H!'menoplerous Insecls in lhe Colleclion of the British lluseum.
Part 2.
- Chalcidites .{ddilional species. London. lE{{1.
Ent n l. Ts. fry. El- 11.31,1960
