A new species of Isocolus from Spain (Hymenoptera, Cynipidae) inducing galls in flower heads of Leuzea conifera (Asteraceae)


Nieves Aldrey, J.L.; Parra, L.A.

Annales de la Societe Entomologique de France 39(1): 49-53

2003


A new species of Isocolus Forster (Hymenoptera, Cynipidae "Aylacini") is described from Spain: Isocolus leuzeae n. sp. The new species induces galls in flower heads of Leuzea conifera (Asteraceae) and represents the first known aylacin species associated with this plant. The species is closely related to Isocolus lichtensteini (Mayr) that induces galls on stems of Centaurea aspera. Biological data on its life cycle, larva and gall are provided.

Ann.
Soc.
entomoi
Fr.
(n.s.),
2003,
39
(1)
:
49-53.
ARTICLE
A
new
species
of
Isocolus
from
Spain
(Hymenoptera,
Cynipidae)
inducing
galls
in
flower
heads
of
Leuzea
conifera
(Asteraceae)
Jose
Luis
NiEvEs-ALDREY*(1)
&
Luis
Alberto
PARRA
(
2
)
(1)
Museo
Nacional
de
Ciencias
Naturales,
Departamento
de
Biodiversidad
y
Biologfa
Evolutiva,
Jose
Gutierrez
Abascal
2,
E-28006
Madrid,
Spain.
(2)
Avenida
del
Padre
Claret
7,
5°G,
E-09400
Aranda
de
Duero,
Burgos,
Espafia
R6sum6
Une
nouvelle
espece
disocolus
d'Espagne
(Hymenoptera,
Cynipidae)
produisant
des
galles
dans
les
akenes
de
Leuzea
conifera
(Asteraceae).—
Isocolus
leuzeae
n.
sp.
(Cynipidae
«Aylacini»)
decrite
d'Espagne
produit
des
galles
dans
les
akenes
de
Leuzea
conifera
(Asteraceae);
c'est
la
premiere
fois
que
l'on
trouve
un
Aylacini
sur
cette
plante.
La
nouvelle
espece
est
fres
proche
d'Isocolus
lichten-
steini
(Mayr)
qui
produit
des
galles
dans
les
tiges
de
Centaurea
aspera.
Abstract
A
new
species
of
Isocolus
Forster
(Hymenoptera,
Cynipidae
"Aylacini")
is
described
from
Spain:
Isocolus
leuzeae
n.
sp.The
new
species
induces
galls
in
flower
heads
of
Leuzea
conifera
(Asteraceae)
and
represents
the
first
known
aylacin
species
associated
with
this
plant.
The
species
is
closely
related
to
Isocolus
lichtensteini
(Mayr)
that
induces
galls
on
stems
of
Centaurea
aspera.
Biological
data
on
its
life
cycle,
larva
and
gall
are
provided.
C
ynipid
gall-wasps
species
inducing
galls
on
herba-
ceous
plants
from
several
families,
mostly
Asteraceae,
Papaveraceae,
Lamiaceae
and
Rosaceae,
are
currently
clas-
sified
within
the
"Aylacini"
(Hymenoptera,
Cynipidae).
Recent
phylogenetic
studies
indicate
that
that
tribe
comprises
the
basal
lineages
of
gall
wasps
(Liljeblad
&
Ronquist
1998;
Ronquist
1999)
but
see
also
Nieves-
Aldrey
(2001).
The
"Aylacini"
are
distributed
across
the
Holarctic
region
but
are
more
species
rich
in
the
Palaearctic,
specially
in
Europe.
The
tribe
is
specially
well
represented
in
the
Mediterranean
Region
and
in
the
East
and
South-East
of
Europe
where
most
species
have
been
recorded,
many
of
them
described
as
new
in
recent
years
by
Zerova
et
al.
(1988).
However
some
of
them
are
still
badly
or
incompletely
known
and
need
further
taxo-
nomic
revision
(Nieves-Aldrey,
personal
observation).
The
genera
of
"Aylacini"
from
western
Europe
were
revised
for
Nieves-Aldrey
(1994)
as
well
as
the
species
from
the
Iberian
Peninsula
(Nieves-Aldrey
2001).
Isocolus
Forster,
1869
is
one
of
the
better
character-
ized
aylacin
genera.
According
to
Liljeblad
&
Ronquist
(1998)
it
belongs
to
one
of
the
most
primitive
phyloge-
*
Corresponding
author.
E-mail:
aldrey@mncn.csic.es
Accept
le
9-08-2002.
netic
lineages
of
cynipids,
the
Isocolus-Neaylax
lineage.
Isocolus
can
be
distinguished
from
other
Aylacini
genera
by
the
following
combination
of
characters:
female
antenna
usually
with
13-14
antennomeres,
first
flagel-
lar
segment
shorter
than
second;
mesopleuron
longitu-
dinally
striated;
marginal
cell
open
on
anterior
margin;
R
1
and
R
s
stopping
near
anterior
margin
of
wing;
hair
fringe
on
distal
margin
of
wing
very
short
or
absent;
fourth
to
seventh
abdominal
terga
densely
micropunctate.
The
distribution
of
Isocolus
is
Palaearctic.
About
15
species
have
been
described
from
West
Palaearctic,
reared
from
galls
on
plants
of
the
Asteraceae
family,
mainly
Centaurea
species
but
also
on
Cirsium,
Serratula
and
Inula
species
(Baumann
&
Brandl
1992;
Nieves-
Aldrey
2001).
One
species
was
described
from
Eastern
Palaearctic
(from
Turkmenistan),
I.
cousiniae
Diakontshuk,
1988,
reared
from
Cousinia
bipinnata
Boiss
(Diakontshuk
1988).
However,
the
status
of
many
species
need
to
be
revised.
The
centre
of
diversity
seems
to
be
in
Eastern
Mediterranean
and
around
the
Black
Sea
from
where
most
species
have
been
described
and
recorded.
From
Western
Europe
six
species
are
known,
three
of
them
plus
a
doubtful
one
have
been
recorded
from
the
Iberian
Peninsula
(Nieves-Aldrey
2001).
The
Iberian
species
are
all
associated
to
species
of
Centaurea,
mainly
Centaurea
scabiosa
and
C.
aspera.
49
66
1
C
J.
L.
NIEVES-ALDREY
&
L.
A.
PARRA
Cynipid
galls
collected
in
the
Centre
of
Spain
asso-
ciated
with
plants
of
the
tribes
Lactuceae
and
Cardueae
(Asteraceae),
particularly
flower
heads
of
Centaurea
and
related
species,
included
an
unknown
species
of
Isocolus
Ashmead
which
is
described
in
this
paper.
All
the
insects
were
reared
from
galls
collected
in
summer,
and
then
kept
indoors
and
forced
to
overwinter
two
months
in
a
fridge
at
5
°C.
Isocolus
leuzeae
n.
sp.
(figs.
1-4)
Type
material
Holotype
female
(in
Museo
Nacional
de
Ciencias
Naturales,
Madrid,
card
mounted,
SPAIN,
Burgos,
Aranda
de
Duero,
Monte
de
La.
Calabaza,
850
m
UTM:
30TVM4914;
ex
gall
in
flower
heads
of
Leuzea
conifera
(L.)
(Asteraceae)
gall
collected
on
6/VIII/1998,
insect
emerged
VI/1999,
L.A.
Parra
leg.
Paratypes:
1
d',
3
9,
same
data
as
holotype,
in
Museo
Nacional
de
Ciencias
Naturales,
Madrid
(catalogue
number
9025);
5
d',
13
9,
La
Rioja,
Enciso,
ex
galls
on
Leuzea
conifera
collected
9/VIII/1998,
emerged
VI,
1999.
Additional
material:
Guadalajara,
Chiloeches,
31/VII/2001,
Madrid,
Valgallego,
4/VIII/2002,
galls
collected
on
Leuzea
conifera
(Nieves-Aldrey
leg.).
Description
Adult.
Body
length,
measured
from
anterior
margin
of
head
to
posterior
margin
of
metasoma,
2.5-2.8
mm
(n
=
4)
for
females;
2
mm
(n
=
1)
for
male.
Coloration
black;
basal
half
of
metasoma,
mouthparts,
antennal
flagellum
and
legs,
excepting
coxae
and
basal
half
of
femora,
reddish
brown.
Head.
Dorsal
view
slightly
more
than
two
times
as
broad
as
long.
POL
about
1,4
times
00L,
posterior
ocellus
separated
from
inner
orbit
of
eye
by
about
2,5
times
its
diameter.
In
ante-
rior
view
(fig.
1A)
1,2
times
as
broad
as
high;
lower
face
not
keeled
medially;
with
facial
striae
radiating
from
dypeus,
scarcely
reaching
compound
eyes
and
lower
margin
of
antennal
sockets.
Upper
face
and
vertex
coriarious;
median
frontal
carina
and
lateral
frontal
carinae
absent.
Ocellar
plate
distinctly
raised.
Lateral
margin
of
gena
bowed,
height
of
malar
space
about
0.5
times
the
height
of
compound
eye.
Clypeus
subquadrate.
Ventral
margin
of
clypeus
slightly
projecting.
Anterior
tentorial
pits
small
but
clearly
indicated.
Epistomal
sulcus
and
clypeo-pleurostomal
lines
weakly
marked.
Antennal
sockets
situated
at
mid-height
of
compound
eye;
distance
between
antennal
rim
and
compound
eye
1.2
times
as
long
as
width
of
antennal
socket
including
rim.
Occiput
with
alutaceous
sculpture
(fig.
1B).
Without
occip-
ital
carina;
only
some
weak
transverse
rugae
present
above
occip-
ital
foramen.
Gular
sulci
free,
well
separated
at
hypostomata.
Oral
foramen
more
than
about
1,5
times
as
long
as
occipital
foramen;
distance
between
oral
and
occipital
foramina
slightly
shorter
than
height
of
occipital
foramen.
Mouthparts.
Mandibles
moderately
large,
right
mandible
with
three
teeth;
left
with
two
teeth.
Maxillary
stipes
about
three
A
X15
PM
B
F
Figure
1
Isocolus
leuzeae
n.
sp.,
female
(SEM).
A,
head
anterior
view.
B,
head
posterior
view.
C,
antenna.
D,
mesosoma
dorsal
view.
E,
mesosoma
lateral
view.
F,
metasoma
lateral
view
times
as
long
as
broad.
Maxillary
palp
five-segmented:
first
segment
very
short,
as
broad
as
long;
second
to
fourth
segments
about
1,5
times
as
long
as
broad;
fifth
segment
long,
two
times
as
long
as
fourth.
Labial
palp
three-segmented:
first
and
third
segments
subequal,
second
segment
about
0,5
times
as
long
as
first
and
third.
Female
antenna
(fig.
1C)
0.7
times
as
long
as
body,
with
13
antennomeres.
Elongate
placodeal
sensilla
present
on
all
flagel-
lomeres
excepting
first.
Scape
1.4
times
as
long
as
pedicd,
pedi-
cel
almost
0.7
times
as
long
as
Fl.
Length
of
Fl
0,8
times
length
of
F2.
F3
2.1
times
as
long
as
broad.
Ultimate
flagellomere
2.2
times
as
long
as
penultimate.
Male
antenna.
14
antennomeres.
F
1
slightly
curved.
Length
of
Fl
0.8
times
length
of
F2.
Mesosoma.
Pronotum
medially
long
(high),
in
anterior
view
ratio
of
median
distance
between
anterior
and
posterior
margins
to
lateral
distance
between
these
margins
about
0.5.
Submedian
pronotal
depressions
oval
transverse,
deep,
open
laterally,
broadly
separated.
Posterior
pronotal
plate
without
sculpture.
Lateral
surface
of
pronotum
coriarious.
50
New
species
of
Isocolus
from
Spain
Mesonotum
(fig.
1D).
Scutum
shining,
minutely
alutaceous.
Median
mesoscutal
impression
weakly
impressed
in
posterior
one
sixth
of
mesoscutum.
Notauli
narrow
and
shallow,
broader
and
convergent
in
posterior
one
third
of
mesoscutum,
slightly
faint
anteriorly.
Scutellar
foveae
with
irregular
sculpture,
sepa-
rated
by
a
broad
septum;
their
inner
posterior
margins
indis-
tinct.
Dorsal
surface
of
scutellum
rugose,
medially
with
a
shal-
low
longitudinal
furrow.
Posterodorsal
and
posterior
margins
of
A
B
'sr
r
/*
F
E
'an
Figure
2
Isocolus
leuzeae
n.
sp.,
female.
A,
left
forewing
(LM).
B,
ovipositor,
lateral
view
from
the
left
side
(LM).
C,
phallus
ventral
view
(SEM).
D,
phallus
dorsal
view
(SEM).
E,
phallus
lateral
view
(SEM).
51
J.
L.
NIEVES-ALDREY
&
L.
A.
PARRA
axillula
distinct.
Lateral
shining
strip
extended
dorsoposteriorly.
Mesopleuron
beneath
mesopleural
triangle
longitudinally
costu-
late
and
shining
(Fig.
1E).
Mesopleural
triangle
distinctly
impressed,
ventral
margin
clearly
marked.
Metanotum.
Metascutellum
conspicuously
constricted
medi-
ally.
Bar
ventral
to
metanotal
trough
almost
smooth.
Metanotal
trough
narrow.
Metapectal-propodeal
complex.
Metapleural
sulcus
meeting
anterior
margin
of
metapectal-propodeal
complex
slightly
above
mid-height
of
latter.
Lateral
propodeal
carinae
relatively
broad
and
flattened
above,
slightly
divergent.
Lateral
and
median
propodeal
area
smooth
and
sparsely
pubescent.
Nucha
moder-
ately
long
dorsally,
longitudinally
rugose.
Legs.
Claws
without
a
basal
lobe
or
tooth.
Forewing
(fig.
2A).
As
long
as
body,
hyaline
and
pubescent.
Marginal
cell
open
along
anterior
margin.
R
1
ending
near
ante-
rior
margin
of
wing;
first
abscissa
of
radius
(2r)
curved
and
radius
(Rs)
slightly
bowed.
Areolet
present,
closed
by
nebulous
to
tubu-
lar
veins.
Hair
fringe
along
apical
very
short
to
almost
absent.
A
VAI5r,
MM.
Mi
OLAMLI
Figure
3
Isocolus
leuzeae
n.
sp.,
mandibles
of
the
larva
(SEM).
A,
left,
dorsal
view.
B,
right,
dorsal
view.
C,
left,
ventral
view.
D,
right,
ventral
view
Ark
.
millagri,-,
_
f
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. _.•
& '
r
,
wii
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it
i.
r
.r
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...
.
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-
.
.
-
r•
''-
•,,
.:7
-
e
—I
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l'it
-.—I
-...
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''41
11101
.
1
4
4/
;
T
.4
01'
;
6
1
9
0
11
1
1,9
-
U
Figure
4
Isocolus
leuzeae
n.
sp.,
host
plant
and
gall.
A,
host
plant,
Leuzea
conifira.
B,
longitudinal
section
of
a
galled
head
flower
and
an
adult
female.
C,
normal
mature
head
flower
(centre)
and
galled
ones
(lateral).
D,
detail
of
a
dissected
larval
chamber
with
a
larva.
52
New
species
of
Isocolus
from
Spain
Metasoma.
Female
metasoma
(fig.
1F).
Third
abdominal
tergum
covering
about
one
third
of
metasoma,
with
a
small
hair
patch
antero-medially,
about
1,5
times
as
long
as
fourth
tergum
along
dorsal
curvature
of
metasoma.
Fourth
to
seventh
terga,
sometimes
posterior
part
of
third
tergum
as
well,
very
minutely
but
distinctly
and
densely
micropunctate,
nude.
Ventral
spine
of
hypopygium
not
projecting,
united
almost
to
apex
with
the
lateral
flaps.
Ovipositor
(fig.
2B).
Basal
part
of
ovipositor
curved
spirally
almost
360
degrees.
Terebra
apically
serrate.
Male
metasoma.
Similar
to
female
metasoma
excepting
as
follows:
Third
tergum
slightly
more
than
twice
as
long
as
fourth
tergum;
without
lateral
pubescent
patch;
micropunctures
pres-
ent
at
posterior
part
of
tergum.
Phallus
(fig.
2C-E).
Apical
part
of
aedeagus
only
slightly
expanded
subapically.
Length
of
paramere
relatively
long,
reach-
ing
beyond
digitus.
Basidorsal
margin
of
parameral
plates
almost
straight.
Larva.
The
larva
is
a
typical
white
U
shaped,
apodous,
13-segmented
cynipid
larva
(fig.
4D).
Mandibles
have
two
teeth
of
different
size,
the
external
longer
and
stronger.
Basal
tooth
of
right
mandible
is
smaller
than
basal
tooth
of
left
mandible
(Fig.
3A-D).
Gall
(fig.
8).
Galls
are
formed
in
flower
heads
of
Leuzea
conifera
(fig
4A).
The
achenes
are
transformed
into
unilocular
oval
galls
with
tough
walls
(fig.
4B,
D).
Galled
achenes
are
fused
forming
a
mass.
Galled
flower-heads
are
distinguished
from
normal
ones
by
their
smaller
size,
the
galled
mass
remaining
almost
entirely
enclosed
by
the
head
flower
involucral
bracts
(fig.
4C).
Diagnosis
and
identification
Closely
related
to
Isocolus
lichtensteini
(Mayr)
that
induces
galls
on
stems
of
Centaurea
aspera
and
C.
melitensis
in
the
Mediterranean
region.
In
the
key
to
species
of
Isocolus
included
in
the
monography
of
Iberian
Cynipidae
(Nieves-Aldrey
2001),
the
new
species
differs
from
I.
lichtensteini
as
follows:
REFERENCES
BAUMANN
T.,
BRANDL
R.
1993
Evolution
of
host
relationships
in
the
genus
Isocolus
Forster
(Hymenoptera:
Cynipidae)
on
Centaurea
(Asteraceae).
Biochemical
Systematics
and
Ecology,
21:
341-349.
DIAKONTSHUK
L.A.
1988
[New
and
little
known
gall
wasps
of
the
subfa-
mily
Cynipinae
(Hymenoptera:
Cynipidae)
from
Central
Asia].
Entomologicheskoye
Obozreniye,
67:
166-181
[In
Russian].
LILJEBLAD
J.,
RONQUIST
F.
1998
A
phylogenetic
analysis
of
higher-level
gall
wasp
relationships
(Hymenoptera:
Cynipidae).
Systematic
Entomologys
23:
229-252.
-
Scutellum
without
longitudinal
depression;
scutellar
foveae
smooth
and shining and
with
their
anterior
margins
closer.
Forewing
with
first
abscissa
of
radius
weakly
angled
and
radius
almost
straight.
Punctures
on
metasomal
tergites
weak
and
faint.
Galls
in
stems
of
Centaurea
aspera
and
C.
melitensis
. .
Isocolus
lichtensteini
-
Scutellum
with
a
weakly
longitudinal
depression;
scutel-
lar
foveae
with
their
anterior
margins
more
broadly
sepa-
rated,
with
rugulose
sculpture
(fig.
3A).
First
abscissa
of
radius
curved
and
radius
slightly
bowed
(fig.
4).
Punctures
on
metasomal
tergites
more
clearly
impressed.
Galls
in
achenes
of
Leuzea
conifera
Isocolus
leuzeae
n.
sp.
Etymology
Named
after
its
host
plant.
Biological
data—
The
species
induces
galls
inside
flower
heads
of
Leuzea
conifera
(Asteraceae).
The
life
cycle
is
typically
univoltine
as
in
most
Aylacini.
Baumann
&
Brandl
(1992)
observed
that
in
most
Isocolus
species
from
Europe,
galling
flower
heads
of
Centaurea
species,
males
were
absent
indicating
parthenogenetic
repro-
duction.
However
it
is
not
the
case
for
the
new
species
where
males
are
not
rare
and
the
reproduction
appears
to
be
bisexual.
Adult
gall-wasps
emerge
in
late
spring
or
early
summer
when
the
host
plant
are
available
in
the
field.
Galls
develop
and
mature
in
summer
and
fully-
grown
larva
are
found
inside
in
September.
Insects
over-
winter
as
larvae
inside
the
galls
and
pupate
next
spring.
Acknowledgements
—We
are
indebted
to
Jose
Bedoya
for
tech-
nical
assistance
with
SEM photomicrographs.
George
Melika
provided
useful
comments
on
the
manuscript.
Financial
support
was
partly
provided
by
the
Research
projects
"Fauna
Iberica
IV",
DGICYT
PB95-0235
and
REN2002-03518
to
J.L.
N-A.
NIEVES-ALDREY
J.
L.
1994
Revision
of
West-European
Genera
of
the
Tribe
Aylacini
Ashmead
(Hymenoptera,
Cynipidae).
Journal
of
Hymenoptera
Research,
3:
175-206.
NIEVES-ALDREY
J.L.
2001
Hymenoptera,
Cynipidae.
In:
Fauna
Iberica,
vol.
XVI,
Ramos
M.A.
et
al
(eds),
Museo
Nacional
de
Ciendas
Naturales
(CSIC),
Madrid,
636
p.
RONQUIST
F.
1999
Phylogeny,
classification
and
evolution
of
the
Cynipoidea.
Zoologica
Scripta,
28:
139-164.
ZEROVA
M.D.,
DIAICONTSHUK
L.,
ERMOLENKO
V.M.
1988
[Gall
formers
ofthe
European
part
ofthe
USSR.
Part
1.
Hymenoptera].
Naukova
Dumka,
Kiev,
180
p.
[in
Russian].
53