A new gall midge (Diptera: Cecidomyiidae), feeding beneath leaf sheaths of Phalaris arundinacea (Poaceae)

11 Pages·1997·1.2 MB·

by  Sylvén, E

A new gall midge (Diptera: Cecidomyiidae), feeding beneath leaf
sheaths of Phalaris arundinacea (Poaceae)
EDVARD SYLVEN, SVEN HELLQVIST, GUNNEL SELLERHOLM &
RUBEN reSrAS-OUqUe
Sylv6n, E., Hellqvist, S., Sellerholm, G. & Tastds-Duque, R.: A new gall midge (Diptera:
Cecidomyiidae) feeding beneath leafsheaths of Phalaris arundinacea (Poaceae). IEn ny gall-
mygga (Diptera: Cecidomyiidae), som livniir sig under bladslidor pi Phalaris arun-
dinacea (Poaceae).1 - Ent. Tidskr. 118(2-3):99-109. Uppsala, Sweden 1997. ISSN 0013-
886x
The gall m\dge Epicalamus phalaridis Sylvdn, gen. and sp. n. is described from reed canary
grass, Phalaris arundinacea L., in northern Sweden. Larvae feed beneath leaf sheaths and the
crop, which is grown for bioenergy and fibre production, lodges. The biology and economic
significance of this new pest is detailed.
Edvard Sylvdn and Gunnel Sellerholm, Section of Entomology, Swedish Museum of Natural
History, Box 50007, 5-104 05 Stockholm, Sweden.
Sven Hellqvist, Department of Agricuhural Researchfor Northern Sweden, Swedish Univer'
sirl of Agricultural Sciences, Box 4097, 5-904 03 Umed, Sweden.
Ruben Tastds-Duque, Department of Zoology, University of Stockholm, S-106 91 Stockholm,
Sweden.
Introduction
Reed canary grass, Phalaris arundinacea L., is when mature, have a bilobed spatula and are per-
native in temperate parts of the Northern Hemi- haps conspecific with those erroneously identified
sphere (Hult6n & Fries1986), and grown as a as Mayetiola phalaris by Tomaszewski. They be-
fodder crop in some areas. Recently P. arundi- long to the tribe Oligotrophini and represent a new
naceahas achieved attention as a crop having po- species of a new genus.
tential for bioenergy and fibre production (Land- E.S. is responsible for text dealing with struc-
strdm et al. 1996, Sandstrrim 1996). tural taxonomy of the midge, and the remaining
Barnes (1927) described a new gall midge spe- text is written by S.H.
cies, Mayetiola phalaris, on the basis of adults
reared from P. arundinacea in Germany by
Blunck. Tomaszewski (1931) identified larvae General remarks
feeding on stems of P. arundinacea as MayetioLa Using the technique described by Sylv6n & Antipa
phalaris, but Ertel (1975) found that this was Neufeld (1991) most specimens included in the
wrong. She noticed, on the basis of Blunck's ori- taxonomical analysis were mounted in Hoyer's
ginal material of Mayetiola phalaris, that the medium (except in each adult one wing that was
mature larva of this species has only one anterior mounted dry) by G.S., who is largely responsible
lobe on the spatula, whereas the larva described also for the production ofthe drawings. The SEM
by Tomaszewski has two lobes. analyses [for technique used see Sylv6n & Tast5s-
In 1996 in an experimental field of P. arundi- Duque (1993: 277)) werc done by R.T. The holo-
nacea at Vojakkala in northern Sweden (65" 52' type and the paratypes are deposited in the gall
N: 24" 05' E) lodging of the crop was observed. midge collection in the Section of Entomology of
At the points of stem breakage gall midge larvae the Swedish Museum of Natural History, Stock-
were found beneath the leaf sheaths. These larvae, holm.
99
Edvard Sylvdn, Sven Hellqvist, Gunnel Sellerholm & RubenTastds-Duque Ent. Tidskr. 118 (1997)
Description Kieffer, type species M. destructor (Say). The last
instar larva and the pupa of Epicalamus do not as
Epicalamus Sylv6n, gen. n. those of Mayetiola develop in a puparium. Struc-
Adult. No. of flagellomeres variable within spe- tural features in Epicalamus deviating from those
cies. Flagellomeres I and II not separated from in the type species and various other species of
each other. Most flagellomeres with a node and a Mayetiola are, e.9., as follows: 1) Each tarsal claw
neck (Figs 1-2), the latter conspicious in males but with a well-developed (not tiny) tooth (Fig. 4); 2)
short in females. Circumfila in both sexes ap- Distal part of each mediobasal lobe of male
pressed against node (Fig. 23). Palpus (Fig. 3) terminalia dorsoventrally narrow (not broadly
with four joints but the two outermost ones (in the rounded, nor more or less blunt-ended) (Fig. 6);
type species at least) frequently not separated 3) Distal part of aedeagus in lateral aspect broadly
from each other. Maxillary bulbus (Fig. 3) presenr. rounded (not strikingly narrow) (Fig. l0).
Tarsal tip (Fig. 4) with claws toothed and with
empodium as long as or somewhat longer than Epicalamus phalaridis Sylv6n, sp.n.
claws. Wing (Fig. 5) with R, joining C slightly Type material. Holotype: adult female reared
anterior of apex. Border of wing j ust beyond inser- from larva collected beneath a leaf sheath on
tion of R. with a naked patch devoid of thick- Phalaris arundinacea, Sweden, Norrbotten,
ening. Urotergites I-V[ in both sexes with narrow Vojakkala, 1996, leg. S. Hellqvist, slide no.
scales (Figs 11,25). Male terminalia (Figs 6-10) 10680. Paratypes 18 adult males, 15 adult fema-
with cercal structure and hypoproct bilobed, and les, 5 pupal skins, and 8 last instar larvae, host
with a pair of mediobasal lobes sheathing aede- plant and locality as above.
agus, this latter remarkably thick. Urotergite VIII Adult. Size as indicated by length of wing see
in female appearing as a pair of longitudinal, Tabs l-2. No. of flagellomeres l5-17 and l4-16 in
broad and diffuse bands (Fig. l1). Female cercal males (n = 16) and females (n = l6), respectively.
lobe (Figs 12-14,27-29) and hypoproct (Figs 13, Distal section of antenna frequently correspon-
28) densely covered with microtrichia. ding to two, occasionally three flagellomeres, not
Pupa. Antennal sheath proximally with a tooth separated and usually without necks. Remaining
(Fig. 20). Face without protuberances. flagellomeres each with a node and a neck (Figs 1-
Last instar larva. Spatula (Figs 15-17) with 2). General colour of abdomen in both sexes
two anterior lobes, and an elongate shaft. orange. Urotergites I-VII in both sexes with setae
Tlpe species. Epicalamus phalaridis Sylv6n, caudally, and with scales > 10, occasionally > 20
sp.n. times as long as wide, frequently thread-like in
Etymology. Epi calamus = on straw. both ends (Fig. 25). Most urotergites in borh sexes
Comparison with related genera. Epicalamus with scattered setae also laterally. Male terminalia
is close to Dasineura Rondani, the type species of with gonocoxites (Figs 6-7) evenly narrowing
which is proposed to be D. sisymbrii (Schrank) towards distal end, and with gonostyli (Figs 8-9)
(see Gagn6 et al. 1991). The following features tapering and strongly bent from base to tip, with
noticed in Epicalamus are among those deviating microtrichial cover extending both dorsally and
from the pattern in the proposed type species and ventrally abolt 314 or 415 of the distance from
various other species of Dasineura: 1) In adult base to tip. Female terminalia with cercal lobe
female eighth urotergite very weak, diffusely mar- (Figs l2-14, 27-29) dorsovenrrally rectangularly
ked (Fig. 1l);2) In adults ofboth sexes urotergite shaped, or broadly rounded distally, equipped
scales remarkably narrow (Figs I 1, 25) (for with setae and a dense cover of largely randomly
comparison with urotergite scales in D. sisymbrii distributed microtrichia, and with hypoproct (Figs
see Fig. 26); 3) Aedeagus remarkably thick (Figs 13, 28) ventrally densely covered with micro-
6, 10); 4) In last instar larva no mamelons present trichia arranged in transverse rows. For morpho-
(cf. species description below) (Figs 18, 19); 5) In metric details of the adult midge see Tabs l-2.
last instar larva also anterior ventral papillae and Pupa. Length of empty and flattened skin 2.8
anal papillae setaceous (Figs 18, l9); 6) Eggs rem- and 2.4 - 3.3 mm in male (n = I ) and females (n =
arkably big (cf. species description below). 3), respectively. Exterior cephalic seta longer than
Another genus akin to Epicalamus is Mayetiola prothoracic horn (Figs 20-21). Dorsum of each of
100
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Edvard Sylvdn, Sven Hellqvist, Gunnel Sellerholm & RubenTastds-DuqueIEnt. Tidskr. ll8 (1997)
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Figs I 1-22. Epicalamus phalaidis. I l - I4, structures in adult Q : I l, end part of abdomen, dorsal view; I2, cercal
lobe, dorsaL view; l3-14, cercal lobe and hypoproct, ventral and lateral view, respectively. l5-19, structures in
mature larva: 15-17, spatula sternalis in three specimens, ventral view: l,8, anterior ventral papillae and
surroundingareasonrighthalfofuromereVll; lg,analpapillaeandsurroundingareasonrighthalfofuromereX.
20'22,structuresinpupa:20,detailoffrontpart,dorsalview;21, prothoracichorn(samespecimenasin20);22,
detail of left haLf of uromere VII, dorsal view. an, anal papilla; av, anterior ventral papilla: ec, exterior cephalic
seta; ed, exterior dorsal papilla; gc, genital chamber: hy, hypoproct: id, interior dorsal papilla; ip, interior ciphalic
papilla; ma, macrospines; mi, microspines; Vll and VIII (in Fig.l I ), tergites. Scale lines: (Figs l l, 20-21) lbT W,
(12-14) 25 ytm, (15-19, 22) 50 1tn.
Epicalamus phalaridis. ll-14, imagostrukturer,9; l5-19, strukturer hos fullvuxen tarv; 20-22, strukturer hos
Puppan.
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Edvard Sylvdn, Sven Hellqvist, Gunnel Sellerholm & Ruben Tastds-Duque Ent. Tidskr. ll8 (1997)
Tab.l.RegressionstatisticsofadultstructuresforEpicalamusphalaridis.LW,arculustowingapexdistance; RW
arculus to distal point of R, distance; BW, wing breadth as indicated by an imaginary line at 9U to and crossing
centre of LW; AL, antennal length; GS, length of gonostylus; OV length of ovipositor from anterior limit of genital
chamber; CE, length offemale cercal lobe (superior lamella) from base of hypoproct (inferior lamello). n, number of
specimens; r,r, product-moment correlation coefficient: b, slope of linear regression tine: C.i. of b, 95 Vo confidence
limitsof b; (b- I)/suindicates'significance'levelof deviationof slopeof tinearregressionlinefromproportionaliD.
(4Sokal &Rohlf, 1995:471-472):^',notsignificant;*P<0.05; **p<0.01 ;*** P<0.001;alllogvaluesare
tolog
values.
Re gre ss ionsstatistik av imago- strukturer fbr Epicalamus phalaridis.
Sex ft, b C.i. of b (b- 1) / sn
log RW on log LW d l6 1.00 l.0l 1.00 - l.0l + 2.02*
log RW on log LW I 4 1.00 1.00 .99 - t.02 + .59n.
log BW on log LW d l6 .97 1.20 1.03 - 1.36 + 2.56*
log BW on log LW t4 .99 t.t4 1.03 - t.25 + 2.13'r
log AL on log LW d 16 .96 .92 .75 - Ll0 - .98,.
log GS on log LW d l6 .92 .63 .47 - .78 ( .).)***
log OV on log LW I t4 .96 .53 .43 - .63 _l0.2l r<{<{<
log CE on log LW I t4 .85 .57 .3s - .80 - 4.17**
uromeres II-VIII with an area covered with thorax), further on the abdomen all ventral
macrospines (Fig. 22). Inner dorsal papillae on papillae (Fig. l8), the terminal papillae, and the
each of the same uromeres without seta (Fig. 22). anal papillae (Fig. l9). Setae of body throughout
Last instar larva. Ground colour orange. short, length of each of the six dorsal setae on pro-
Length of empty and flattened skin 3.9-4.4 mm (n thorax, for example, only about 2 or 3 %" of length
= 7). Most of skin covered with either circular of emptied and flattened skin.
(Fig. l9) or (in front of ventrum of most segments) Egg. Shape and size of eggs from dissected
acute verrucae (Fig. l8). On either longitudinal females as follows: elongate, more or less
half of each thoracic segment normally five lateral ellipsoidal, 0.42 - 0.46 mm long by 0.09 - 0.12 mm
papillae, viz. one inner group with three papillae wide (n = 30). Note: size of eggs almost or entirely
(two of them with and one papilla without seta), independent of size of females producing them.
and one outer group with two papillae (each with a
seta). On ninth uromere up to four terminal pa-
pillae on each body half, and on tenth uromere up Occurrence of midge and symptoms of attack
to two anal papillae on each body half. Otherwise The experimental field in Vojakkala, where the
see Fig. 5 in Sylv6n (1975) for number and distri- gall midge was found, was 42 x 28 m, and was
bution of various kinds of papillae on thorax and established in l99l with the P. arundinacea va-
abdomen. Most papillae setaceous, inter alia the riety 'Palaton'. Most plots in this field have been
ordinary dorsal papillae, the sternal papillae on harvested each year in late autumn or early spring,
meso- and metathorax (but normally not on pro- and a few plots in August. Symptoms of midge at-
t04
Ent. Tidskr. I l8 (1997) A new gall midge
Tab. 2. Morphometics of adult structures for Epicalamus phalaridis. For explanation of LW, RW, etc., see Tab. l.
BW,' GS,, OV,, and CE, refer to convertedfigures [Log values of BW, GS, etc., converted accortling to respective
linear regression lines (log BW on log LW, etc., see Tab, I ) into values corresponding to log LW = S.:Ot O 1= tog oy
2 000 W)' and expressed as antilog / 201. For further details of conversion procedure utid ,"" Sylvin & Lr;viren
( 1995). n, number of specimens; C.i., 95 7c confidence interval ofmean.
Mtitytirde n av imago st rukturer fdr Epicalamus phalaridis.
Sex Ci c.i.
dI 1146 RRWWLLWW ((77oo)) 9989..7t -- 9999..14 LLWW ((mmmm)) 21..09 -- 22..13
d
I 16 BW/LW (7o) 42.3 - 44.3 BW 42.3 - 44.o
t4 BWLW (7o) 40.9 - 42.9 BW 4t.0 - 42.3
d l6 AL/LW (Eo) 80.3 - 83.8
d
16 GS/LW (7o) 4.8 - 5.1 GS 4.9 - 5.1
I
t4 ov/tw (%) 22.5 - 24.7 OV 23.4 - 24.t
t4 CEfi,W (Va) 4.0 - 4.4 CE 4.1 - 4.4
tack were first noticed in mid August 1996, and attack on 1.3 (S.D. = 0.89) of these, with interno-
the field was examined in mid September of the des 2-3 being most frequently attacked. There
same year. Then only a few shoots were standing were about I 100 attacked internodes per square
upright (Fig. 30), and several shoots, mainly weak meter in the field, corresponding to about 100 000
sterile ones, had wilted. On attacked internodes gall midge larvae per square meter.
midge larvae were mostly found at the lower part,
close to the node. The stem had turned blackish
and soft at the site where the larvae occurred, but
galls had not been produced, and there were no
external symptoms on the leaf sheath (Fig. 31).
The larvae lived gregariously, and in one case as
many as about 650 mature larvae were found
beneath a single leaf sheath.
In 16 randomly selected small plots (13 x 13
cm), in the part of the field that was harvested in
the spring, all shoots were cut at ground level.
Each internode of the shoots was examined for
symptoms of midge attack. All examined fertile
shoots (n = 42) and78 Vc of the sterile ones (n = Fig. 30. Lodging of Phalaris arundinacea due to attack
158) were attacked by midge larvae on at least one by Epicalamus phalaridis. Sterile shoots have emerged
internode. Fertile shoots had on average 6.0 inter- through a dense layer of broken shoots on the ground.
nodes (S.D. = 0.79) and on average 2.5 (S.D. = Vojakkala, September, 1996. Photo: Sven Hellqvist.
0.83) of these were attacked, with the highest
Ett rbtflensbestdnd har lagt sig efter angrepp av gall-
incidence of attack on intemodes 2-4 (counted myggan E. phalaridis. Sterila skott skjuter upp genom
from the stem base) (Fig. 33). Sterile shoots had ett tjockt lager av skott, som vikt sig. Norrbotten,
on average 5.0 internodes (S.D. = 1.91) and larval Vojakkala, september I 996.
05
Edvard Sylv,in, Sven Hellqvist, Gunnel Sellerholm & Ruben Tastds-Duque Ent. Tidskr. 118 (1997)
Fig. 32. Female Epicalamus phalaridis during ovipo-
,sition on Phalaris arundinacea. Ph()to: Sven Hellqvist.
Hona av gallm-,-ggan Epicalamus phalaridis under rigg-
liiggning pd rorflen.
attacked shoots). Several other experimental
fields with P. arundinacec in different parts of
Sweden and Finland, were inspected in August
and September 1996. Larvae of the new species
were not found in these fields. In 1997, the midge
was found on wildgrowing P, arundinacea on the
bank of Kalix river, ca 50 km W ofVojakkala.
Fig. 31. Damage byEpicalamus phalaidis on shottts of
Egg laying
Phalaris arundinacea. At arrangement of the shoots for
photography the stems was parll,v- drawn out from the The number of eggs in eight dissected, newly
leaf sheaths in order to show symptoms of attack. Note emerged females of different sizes varied from 58
the dark colour and soft appearance of the stems at the to 355. In the greenhouse oviposition on 170
lower part of the internodes. Mature midge Larvae are shoots ofP arundinacea was observed. Eggs were
seen in the background. Photo: Sven HeLlqvist. in most cases (92 7o) laid at the base of the leaves,
on the upper leaf surface, close to the junction
Skador av E. phalari.dis pd skott av rdrflen. Strdna har between the ligule and the lamina. They were
delvis dragits ut frdn bladslidorna fdr att visa symPto'
men. Observera att strdna vid internodernas nedre del deposited in rounded or elongated multilayered
cir mjuka och mdrkfeirgade. Fullvuxna larver s1'ns i bak- clusters (1-2 mm in diameter) or as a transverse
grunden. band across the leaf base. The number of eggs in
larger clusters were more than 100. Eggs had a
Observations in September showed, that most bright orange colour and the egg clusters were
of the larvae had left the shoots and were in clearly visible with the naked eye. Most egg
cocoons at the soil surface. Most cocoons were clusters were laid on the uppermost fully ex-
attached to plant debris at the base of the shoots panded leaf of the shoot (88 7o) or on the second
and on the ground, but a few also occurred in the uppermost leaf ( l0 7o). While ovipositing, the fe-
uppermost part of the mineral soil (in this case a male grasped the rolled, emerging leaf at the
silt loam). shoot apex and inserted the ovipositor between
The midge was also found in two other experi- the ligule and the lamina of the expanded leaf
mental fields with P. arundinacea at Vojakkala, as (Fig.32). On 8 Vo of the shoots, the eggs were not
well as on wildgrowing P. arundinacea in the vi- laid at the base of the leaf lamina, but further out
cinity, on the bank of Torne river. In these cases on the leaf, on either side of the lamina. In these
the incidence of attack was, however, low (< 5 Vo cases, the egg clusters were generally much
106
Ent. Tidskr. I l8 (1997) A new gall midge
smaller than those at the leaf base. Up to four egg
clusters from a single female have been obser- s 80
ved. I lertile shoots
o6_ n sterile shoots
Euo
Io
Seasonal occurrence 'E
+o
There are no data on the oviposition period and o
E
the development time for the midge. However, o
620
the pattern of attack on the shoots (Fig. 33) indi- 6
cates that there was a single generation in
Vojakkala in 1996, with oviposition probably 0 12t,l,"rno.u"678
from mid June to early July (based on fenology
of P. arundinacea and the observation that the Fig. 33. Distribution of attack by Epicalamus phaln-
uppermost leaves are primarily chosen for ovi- ridis among internodes ofPhalaris arundinacea (inter-
position). Mature larvae collected in Vojakkala node I = the lowest prolonged internode on the shoot).
in August and September readily pupated and Vojakkala, September I 996.
emerged as adults after about two weeks at room
temperature, indicating that the larvae do not Fdrdelning av angrepp av E. phalaridis mellan inter-
necessarily enter diapause. More than one gene- noder av rii(\en, Phalaris arundinacea (internod I =
ration per year may therefore be expected in war- den nederstaft)rkingda internoden pd skottet). Norrbot-
mer summers (the spring and early summer were ten, Vojakkala, september 1996.
unusually cold in northern Sweden in 1996) or at
more southern localities.
Judging from the observations in Vojakkala in
1996, the new gall midge appears to be of minor
Economic importance importance if P. arundinacea is grown as a fodder
Most of the attacked shoots of P. arundinacea crop. The dry matter yield is slightly or not ar all
appeared to be able to reach about normal length affected (see above), and because the crop is
before the internodes became soft and lodging harvested early, probably before the larvae have
occurred late in the season. The length of midge reached maturity, the midge will have little
attacked fertile shoots from the heavily infested opportunity to multiply in the field.
field in Vojakkala was on average 140 cm (S.D. = The midge may have greater importance if p
33.8; n = 42), only slightly shorter than arundinacea is grown for bioenergy or fibre
unattacked shoots from a nearby field with the production. Under such circumstances a prom-
same P arundinacea variety (on average 152 cm; ising production method is to harvest P. arundi-
S.D.=22.6; n=19). nacea as a senescent, dry crop in the early spring.
Some plots in the heavily infested field were This method yields a high quality producr (having
harvested in late August 1996. The dry matter low ash content) with no need for artificial drying
yield in these plots was on average 27 Vo lower and with low fertilization costs (Landstrtim et al.
than the corresponding yield in the previous year. 1996). Lodging of the crop due to midge attack
There was, however, a yield reduction (17 Vo) in will probably reduce the amounts of plant
1996 also in the nearby field where only a few nutrients that are translocated from leaves and
shoots were midge attacked. The effect of midge stems to roots and rhizomes in the autumn. The
damage on the dry matter yield of P. arundinacea resulting higher content of nutrients in the above
may consequently be rather low, even at high ground parts of the crop may result in higher
levels of attack. In the heavily infested field, the winter losses due to microbial decomposition. As
midges must have been present in rather high mentioned above midge attacked stems turn black
densities already in 1995, even though this was not and soft, and they will therefore probably have a
noticed. Nevertheless, the dry matter yield in the low value as a source for fibre. The lodged crop
field increased with about 20 Vo from 1994 to will also be more difficult to harvest. Further, the
1995. gall midge will have good opportunities to
107
Edvard Sylvin, Sven Hellqvist, Gunnel Sellerholm & Ruben Tastds-Duque Ent. Tidskr. I l8 ( 1997)
muttiply in the field, in a production system with Diptera): proposed designation of Tipula sisl'mbrii
spring harvest. Schrank, 1803 as the type species. - Bull. zool. Nom.
It might seem surprising that an insect species 54 (2):92-94.
Hult6n, E. & Fries, M. 1986. Atlas of North European
that is capable of occurring at very high densities vascular plants north of the Tropic of Cancer. Vol. I-
on a crop, has escaped discovery until now. One Ill. ll72 pp. Kdnigstein (Koeltz Scientific Books).
cause may be the new cultivation system (spring Landstriim, S., Lomakka, L. & Andersson, S. t996.
harvest) that now allows the midge to reproduce in Harvest in spring improves yield and quality in reed
the field with no disturbance during the growing canary grass as bioenergy crop. - Biomass and
season. The spring harvest system may also inter- Bioenergy I l:333-341.
fere with the action of natural enemies. Several Sandstr<im, D.A. 1996. Rrirflen - rivara fdr pappersin-
hundreds of adult midges have been reared from dustrin. - Svensk Papp-Tidn./Nordisk Cellulosa 1996
(7):25-26.
cocoons from the heavily infested field, but only
I Sokal, R.R. & Rohlf, F.J. 1995. Biometry. The princip-
very few parasitoids [about Eo parusitized by
les and practise of statistics in biological research. 3rd
Platygaster sp. (Hymenoptera: Platygasteridae)]. ed. 887 pp. San Francisco (Freeman).
On the other hand, on the single shoot of wild- Sylv6n, E. 1975. Study on relationships between habits
growing P. arundinacea where midge larvae and external structures in Oligotrophidi larvae
were found, almost all larvae were dead, para- (Diptera. Cecidomyiidae). - Zool. Scr. 4: 55-92.
sitized by Tetrastichus sp. (Hymenoptera: Eulo- Sylv6n, E. & Antipa Neufeld, M. 1991. A preparation
phidae). This parasitoid overwinters as larvae in method for gall midges. - Ent. Tidskr. I l2: t53- 155.
killed host larvae beneath a leaf sheath on the Sylv6n, E. & L6vgren, L.1995. Dasineura ingeris sp.n.
(Diptera: Cecidomyiidae) on Sa/rx viminalis in Swe-
straw. During a spring harvest, these parasitoids
den, including comparisons with some other Dasi-
will be removed from the field, while unpara-
neura species on Sa1ix. - Syst. Entomol. 20: 59-7 I .
sitized midge larvae escape removal because they Sylv6n, E. & Tastiis-Duque, R. 1993. Adaptive, taxo-
overwinter on the ground. nomic, and phylogenetic aspects of female abdominal
features in Oligotrophini (Diptera, Cecidomyiidae),
and four new Dasineura species from Western
Acknowledgements Palearctic. - Zool. Scr. 22:277-298.
We gratefully acknowledge Mr Bertil Lomakka at Tastds-Duque, R. & Sylv6n, E. 1989. Sensilla and
Vojakkala Experimental Station who first noticed attack cuticular appendages on the female abdomen of
by the new gall midge, Miss Malin Barrlund who Las iopte ra rabi (Schrank) (Diptera, Cecidomyiidae).
assisted with the field work, and Dr Staffan Landstrdm - Acta zool., Stockh. 70: 163-l'74.
who kindly provided data on P arundinacea yields at Tomaszewski, W. 193 l. Cecidomyiden (Gallmiicken)
Vojakkala. Our thanks are also due to Dr Raymond als Grasschiidlinge. - Arb. biol. ReichAnst. Land - u.
Gagn6 (Washington, D.C.), Dr Keith Harris (Woking, Forstw. l9: l-15.
UK), and Dr Marcela Skuhravri (Praha). They kindly
critically commented questions in connection with the
present study. Further we are indebted to Dr Karl-Johan
Hedqvist (Tiiby, Sweden) who kindly identified the Sammanfattning
hymenopterous parasites. Studies ofthe new gall midge Rcirflen, Phalaris arundinacea L., har liinge od-
is financially supported by Stiftelsen Lantbruksforsk- lats som fodergrdda men under senare tid mest
ning, NUTEK and Vattenfall within "Ramprogram Str6- uppmarksammats som en grdda med potential fdr
briinslen". bioenergi- och fiberproduktion. I ett ftirstjksfiilt
med rOrflen i Vojakkala, Norrbotten, fcirekom un-
der 1996 angrepp av en ny gallmygga, som ovan
References beskrivits under namnel Epicalamus phalaridis
Barnes, H.F. 192'1 . A new gall midge (Mayetiola Sylv6n, gen. och sp.n. Det nya sliikte, som arten
phalaris sp.n.) reared from Phalaris arundinacea. - fcirts till, stflr niira Dasineura Rondani.
Z. angew. Ent. l3: 375-377 . Tidigare har en annan gallmygga beskrivits frin
Ertel, M. 1975. Untersuchungen zur Larvalsystematik
r6rflen, Mayetiola phalaris Barnes 1927, men
der Gattung Mayetiola (Cecidomyiidae, Diptera). -
Stuttg. Beitr. Naturk., Ser. A, Nr. 267: l-64. denna art fcirpuppar sig i ett puparium, vilket inte
Gagn6, R.J., Harris, K.M., Skuhravd, M., Solinas, M. & gliller den nya arten. Tomaszewski (1930) identi-
Sylvdn, E. 1997. Dasineura Rondani 1840 (Insecta, fierade av honom pi rcirflen pitraffade larver som
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