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Pcecilostoma, Dbm., Consp., 5.
Empyria, Brulle Hymen, iv, 666.

Wings with two radial and four (sometimes only three) cubital
cellules. Lanceolate cellule with an oblique cross nervure. Transverse
median nervure received in middle of median cellule. Hind wings with
the recurrent nervure present, the transverse cubital absent, accessory
nervure shortly appendiculated. Antennae short, rarely longer than
abdomen, thin, attenuated at apex, rarely thick, with the joints trun-
cated at the apex. Abdomen oblong, widening out from the third seg-
ment ; blotch distinct. Eyes not reaching to base of abdomen. Clypeus
incised. Legs longish, patellso distinct ; claws bifid, or with a minute
tooth at the apex.

The ground colour of the abdomen is usually black,
rarely luteous. When not entirely luteous the seg-
ments are lined with white or luteous, and the apical
segments may be entirely luteous. The legs with one
group are luteous, with another black, marked with
white at the knees. The stigma is luteous or black, as
the legs are black or luteous. With the black species
the dorsal abdominal segments bear white markings*

The alar neuration is subject to considerable varia-
tion. With the black-legged species the first transverse



GENUS POBOILOSOMA. 207

cubital nervure is usually absent, either constantly in
particular species, or occasionally with certain species.
In the same way the hind wings may want the recur-
rent nervure, and when this is combined with the
absence of the first transverse cubital nervure in the
front wings, we get the neuration of Emphytus. The
relative size of the third cubital cellule varies in the
different species, as does also the position of the
recurrent nervures.

The larvaB are similar to those of Tavonus, and have
the same habits. Nine European species are known
and two North American.



s of Species.

1 (2) Abdomen luteous. Antenna} short, thick, the joints sharply cut

off from each other and slightly produced at the apices
beneath. Wings with four cubital cellules, hind wings with
the recurrent nervure present. Head distinctly inflated
behind the eyes. Clypeus deeply incised. Antenna! fovea
large (=Monostegia > Costa). Luteolum.

2 (1) Abdomen black.

3 (8) Legs for the greater part white or luteous, the abdominal seg-

ments broadly bordered with white.

4 (5) Hind wings with the recurrent nervure absent. Antennas not

much longer than double the length of the head, third joint
not much longer than fourth. Face and orbits of eyes white.
Clypeus broadly, but not deeply emarginated, Claws with a
minute subapical tooth. Candidatum.

5 (4) Hind wings with the recurrent nervure present. Antennae dis-

tinctly longer than head and thorax.

6 (7) Legs entirely luteous, first transverse cubital nervure present.

Antennae short, the third joint much longer than fourth ;
third cubital cellule long and narrow. Pulveratum.

7 (6) Femora lined with black, first transverse cubital nervure absent.

Antennas longish, attenuated at the apex ; third (second)
cubital cellule short and broad. Fletcheri.

8 (3) Abdomen and legs black ; pronotum with a white line ; abdomen

often bearing white lateral spots. Recurrent nervure in
hind wings present ; first cubital nervure often absent
(=guttatum, Fall, and impressum, Kl.).

9 (16) Pronotum lined with white.

10 (11) Hinder calcaria a third of the length of metatarsus, antenna;

thickish, wings infuscated, claws bifid. Guttatum.

11 (10) Hinder calcaria not a third of the length of metatarsus ; antenna?

attenuated at the apex ; wings subhyaline.

12 (15) Posterior tibiae and tarsi not broadly white at base ; costa and

stigma black, clypeus truncated at apex.



208 POSOILOSOMA LUTEOLUM.

13 (14) Claws almost bifid, antennae longish, in $ longer than the body.

Longicorne.

14 (13) Claws with a subapical tooth. Antennae short ; in $ not much

longer than abdomen. Submuticum.

15 (12) Tibiae and tarsi broadly white, costa and stigma dull testaceous ;

clypeus deeply incised. Excisum.

16 (9) Pronotum entirely black, antennae short, thick. Nigricolle.



1. PCECILOSOMA LUTEOLUM.

PL IV, fig. 12, Larva,

Tenthredo luteola, Klug, Berl. Mag., viii, 9; Htg., Blattw., 28],

52 (Eriocampa).

Menostegia luteola, Costa, F. N., 1861.
Selandria luteola, Kalt., Pfl., 423, 426.
Pcecilosoma luteola, Thorns., Op., 288, 2; Hym. Sc., i, 228.
Eriocampa luteola, Andre, Species, i, 319 ; Cat., 10,* 2.

Antennae shorter than the head and thorax, thickish, a little dilated
at the apex ; first joint a fourth longer and thicker than the second ;
third a quarter longer than the fourth ; remaining joints becoming
gradually shorter ; black, pale luteous beneath, and covered with a
short pile. Head black, half shining, densely covered with a short
pile ; frontal sutures invisible ; apex of clypeus and labrum luteous.
Thorax black, pilose; breast and pleurae very smooth and shining,
slightly pilose. Tegulae and pronotum luteous ; cenchri large, pale
white. Sutures of mesonotum moderately deep. Abdomen luteous, a
very little narrower than the thorax, of nearly uniform breadth, blunt
at the apex; blotch large, pale white; sheath black, projecting. Legs
luteous, the apices of the tarsi fuscous. Wings longish, with a smoky
tinge, yellowish at the base, more hyaline at the apex ; costa luteous
at the base, the apex with the stigma fuscous ; nervures yellowish at
the base, blackish at the apex ; the first radial cellule smaller than the
second, tr. radial nervure curved, received a little beyond the middle of
the third cubital cellule ; first cubital cellule a little shorter than the
second, a half wider at the base than at the apex ; second narrow, of
nearly equal width throughout, except where the recurrent nervure is
received ; third a fourth longer, more than double the width of its base
at the apex ; fourth a little longer than the first two ; the second
recurrent nervure is curved, and is received a little in front of the
middle of the cellule.

Length 3^ lines.

The c? is unknown to me, and appears to be very
rare.

Lutecium differs from all the other species of Pcecilo-
soma in the colour of the abdomen. It resembles very
much the yellow species of Seiandria in many respects,
but is best, I think (unless it be placed in a genus by



PCECILOSOMA LUTEOLUM. 209

itself as lias been done by Costa), regarded as a Pcccilo-
soma, although it differs considerably from the other
species of that genus, not only in coloration, but also
in form. From Selandria it differs in the structure
of the antenna3, of the lanceolate cellule, and in the
neuration of the hind wings.

The larva feeds on LysimacJda vulgar is, and, accord-
ing to Kaltenbach, on Anagallis arvensis, during
August and September. It is cylindrical, glabrous,
save a very short white down on the head. The head
is pale yellow, with a large black mark on the vertex,
narrow before and behind, and extending from the
back of the head till it reaches the level of the eyes,
which are black. Mouth piceous ; mandibles darker.
Body dark green to the spiracles ; below these the
colour is white. Legs white ; on the femur is a pale
fuscous line ; and there is also a fuscous line over the
ventral legs. The skin is in folds, the folds being darker
at the junction of the segments.

At the last moult the head loses the black mark ;
the colour of the body becomes paler, and assumes a
yellowish tinge, besides becoming more shining.

The larva when not eating remains curled up in a
ring on the lower side of the leaf. It does not spin a
cocoon.

Kaltenbach says that he found the larva also at
the beginning of July, and hence suspects that there
are two generations in the year.

I believe luteolum will prove to be a common species
in the south. There are specimens in Stephens' s
collection, and it has been taken by Mr. Dale at
Glanvilles' Wootton, by Mr. Bridgman at Norwich, and
by Mr. Fletcher at Worcester.

It has a 'tolerably wide European distribution, being
found in Sweden, Germany, Holland, Italy and
Syria.



VOL. i. 14



210 PCECILOSOMA CANDIDATUM.



2. PGECILOSOMA OANDIDATUM.

Tenthredo candidate*, Fall., Acta Holm., 1807, 105, 40.

repanda, Klug, Berl. Mag., viii, 77, 64 ; Htg., Blattw.,
279, 45.

Selandria bipunctata, Tasch., Ins. f. Gart., 160 (lar.).

Pcecilosoma candidata, Thorns., Opus., 288, 3 ; Hym. Scand., i,
230, 3 ; Toll., Tidj. Ent., xix, 258,
pi. x (lar. im., &c.).

Eriocampa repanda, Andre, Species, i, 319 ; Cat., 40,* 3.

Black ; covered with a short pubescence ; labrum, clypeus, mandibles,
orbits of the eyes, save a small bit above the antenna, and legs pale
testaceous ; tegulse, the edge of pronotum, a spot on hinder edge of
tnesopleura, and the edges of all the abdominal segments, white. The
greater part of coxai and femora black. "Wings hyaline; costa and
stigma dull testaceous. Antennae not much longer than thorax, the
third joint not much longer than fourth, the rest about equal. The
second cubital cellule is not much longer than third, and receives the
recurrent nervure not far from the middle; the second recurrent is
received in the basal third of cellule; transverse median nervure is
received a little before middle of cellule. The accessory nervure in
hind wing is shortly appendiculated. ? .

Length 3| lines.

The larva is dull yellowish- white, yellowish on the
head, except the mouth and eye spots which are darker.
It lives boring in the pith of rose branches during
the second half of May, June, and sometimes on to the
first half of July. Towards the middle of April or com-
mencement of May the fly appears, and lays her eggs
singly in the point of the young branches. The larva
soon bores into the pith, whereby the leaves become
withered, and then damage is done to the plant. It
eats about an inch and a half into the branch, and
when it reaches maturity, bores a round hole in the
side of its habitation and drops to the ground, where
it spins a cocoon.

Apparently a rare species. The only British locality
I know is Oxford where it has been taken by Prof.
Westwood. Cf. Van Vollenhoven, I.e.



PCECILOSOMA PULVERATUM. 211



3. P(ECILOSOMA PULVERATUM.

Plate II, figs. 2 and 2a, larva ; Plate XX, fig. 8, Saw.

Tcnthredo pulveratum, Rctz., Degeer, 304; De Geer, Mem., ii,

291, t. 34, figs. 2025 (lar.) ;
Fall., Acta, 1808, 105, 38 ; Dbm.,
Claris, 34, 53.

olesa, Klug, Berl. Mag., viii, 164; Htg., Blattw.,
302, 13 (Poecilosoma), Brischke,
Beschr., 5, t. i, fig. 1 (lar.).
leucozonias, Htg., Blattw., 290, 15.

AUantus leucozonias, Rudow, S. E. Z., 1871, 137.

Poecilosoma pulveratum, Thorns., Op., 288, 1 ; Hym. Sc., i, 229,

2; Cam., E. M. M., xv, 12;
Fauna, 19, 1; Voll., Tidj. Ent.,
xxiii, 7, pi. 2 (lar., &c.) ; Andre,
Species, i, 332, pi. xx, figs. 4, 6,
8 (lar.); Cat., 42,* 3; cf. also
Bergman, Wet. Acad. Handl.,
1763, 161.

Black, sinning, smooth, covered with a close greyish pubescence ;
tegulee, edge of pronotum and the abdominal segments at their junc-
ture, white. Legs and apex of abdomen reddish-ochreous. Wings
hyaline; costa and stigma sordid testaceous; nervures black at the
apex, pale at the base ; saw projecting, the sheath black ; cerci small ;
posterior tarsi fuscous ; palpi fuscous.
Ab. a. Abdominal segments without white bands.
b. Labrurn white.
., c. Anal segment black.

c?. Apex of posterior femora and tibia? and tarsi fuscous.
Length 3 4 lines.

The <$ of this insect has never been discovered, and
there is good reason for believing that parthenogenesis
plays a normal role with it. This is shown by the fol-
lowing observation. Early in May I found in one of
my breeding bottles two ? specimens, one dead, the
other apparently but newly emerged, and there was
no trace of a male. The living specimen was taken
out of the bottle and placed under a bell glass along
with a fresh sprig of alder. In a short time it layed a
number of eggs, most of which produced Iarva3, thus
showing conclusively that the insect can propagate
without having connection with the male.

The manner of oviposition was as follows : Until



212 PCECILOSOMA PULVEBATUM.

placed in the sunshine the insect was very sluggish,,
but at once on feeling the sunshine became very lively,
and flew up and down the enclosure. After a time it
discovered the food plant, examined it all over, and
ultimately fixed upon a young, half -grown leaf, in
which to lay the eggs. At first it rested motionless in
the middle of the leaf, then came close to the border,
fixed the outer legs along the edge, then raised the body
so that it was a little more than the height of the
tibise above the surface of the leaf. In this position it
remained for about a couple of seconds, then the abdo-
men was bent down, the saw inserted into the leaf and
apparently moved up and down, but without being
entirely withdrawn out of the leaf. The saw was not
inserted straight down, but was a little bent forward,
the two sheaths remaining at right angles and not fol-
lowing the position of the saw. After being in the
leaf for a few seconds the saw was withdrawn, the
insect remained motionless for a second or two, and
then the abdomen was again bent down, the saw
inserted (but not I think deeply), and the egg de-
posited. During the egg-laying the antennae were a
little raised above the height of the head with a slight
curve, and remained almost rigid. The whole opera-
tion lasted about eighty or ninety seconds. Several
minutes elapsed before the next ovipositioii took place.
All the eggs were deposited on thick half -grown leaves,
sometimes singly, sometimes as many as three on the
same leaf. They were placed close to, but not touch-
ing any of the nerves, and on the underside of the
leaf.

Immediately after being laid they were quite invi-
sible, but by twenty-four hours they had swollen up
very much, and were easily noticed as greenish oblong
elevations. As the larva came to maturity a small
open space separated the egg from the leaf, forming a
trench, as it were, round it. With two other experi-
ments I was more successful and managed to rear
females from eggs laid by virgin females.



PGECILOSOMA FLETCHER!. 213

The larva lias a long, cylindrical body, narrowed
towards the end ; the head small, ground colour pale
green, bearing a few scattered hairs, and covered with
a very fine granular white powder. Body of the same
colour as the head, but with a deeper greenish tint ; a
white line (of the same tint as the head) goes down the
sides, and there is another on the back. The skin is in
folds and much wrinkled, and like the head is covered
with a fine powder. The eyes are black, mouth brown,
legs pale green.

At the last moult it loses the green colour, and
becomes of a dirty drab colour. Two or three of them
feed on the same leaf, resting flat on the underside, and
eating roundish holes in the leaf . According to Van
Vollenhoven they spin a cocoon, but they never did
this with me ; even when earth was supplied, they pre-
ferred to bore into the cork of the bottle which held
them, where they pupated without spinning a cocoon,
rather than burying themselves in the earth.

Commonly distributed over Scotland, the imago
appearing at the end of May and beginning of June.
Norwich (Bridgman).

Continental distribution : Scandinavia, Denmark,
Germany, Holland, France, Switzerland, Tyrol.



4. PODCILOSOMA FLETCHERI.
Plate XI, fig. 4, ? .

Pcecilosoma obtusa, Thorns., Opus., 289, 5 ; Hym. Sc., i, 231, 4

(nec,KL).

Fletcheri, Cam., Fauna, 20, 2 ; Andre, Species, i,
332, Cat. 42,* 1.

Antennae a little longer than the abdomen, almost filiform, attenuate
at the apex, slightly pilose, the third joint a very little longer than the
fourth, the rest of the joints shorter. Head black, covered with a dense
greyish pubescence, the front broadly projecting ; antennal fovea3
small ; labrum and palpi sordid white. Thorax and abdomen shining,
covered with a greyish pubescence ; tegulae and edge of pronotum
broadly white ; cenchri very large, clear white ; blotch large. Abdo-
men short, thick, dilated and obtuse at the apex, and a little projecting
above. Saw black, projecting a little. The edges of the segments are
broadly white, the anal segment of a dirty luteous colour ; the sides are



214 PCEOILOSOMA FLETOHBEI.

marked with dirty-white splashes between the white segmental marks.
Legs covered with a grey pile ; coxae and trochanters black ; femora
obscure luteous, lined with black above and beneath ; tibiae white at the
base, the apex sordid luteous, splashed with black ; tarsi fuscous, paler
at the base; claws bifid. Wings hyaline ; costa at the base pale testa-
ceous; apex and stigma sordid luteous. The tr. radial nervure is
received a fourth of the length of the cellule from the apex ; the first
tr. cubital nervure is absent ; the second (first)^ cellule is 'a little
longer than the third (second), narrow, and having a horny point at its
apex ; the third (second) is much broader, double the breadth of the
base at the apex ; the apical cellule is shorter than the preceding.

The $ has the femora and tibiae obscure luteoue, according to
Thomson.

Length nearly 3? lines.

Of similar form to pulveratum, but smaller ; there
are only three cubital cellules ; the second (the third in
pulvemtum) is shorter and much broader; the coxae
and trochanters are quite black ; the body is more
densely pilose, the white marks on the abdomen, too,
are broader than those on the sides, being very con-
spicuous, while they are not found in pulveratum.
From Oandidatum it is known by its more pilose body,
the eyes not having a white border, and otherwise is
easily known by the structure of the posterior wings.

Seemingly a rare species. I have only seen two
British specimens, one taken by Dr. Sharp at Brae-
mar, the other by myself at Rannoch.

Thomson has doubtfully adopted the name of obtu-
sum for this insect, but it seems to me to be very dif-
ferent from the obtusum of Klug. Thus, it has the
antennas as long, if not longer than the abdomen ; in
obtusum they are only as long as the thorax ; the cly-
peus is black, in the other species white ; there is a
distinct white line on the pronotum ; the legs differ in
coloration and also the abdomen ; and, lastly, Klug's
insect is larger than pulveratum, while Fletcheri is
smaller. I can find no record of obtusum beyond the
original locality given by Klug, namely, Hungary. It
is possible that obtusum may have been founded on an
extreme variety of pulveratum, with which, indeed, the
description agrees except in one point, namely, the
description given of the colour of the legs, which are



PGECILOSOMA GUTTATUM. 215

stated to be "pech brun," which scarcely applies to
any specimens of pulveratum I have seen ; and, as
already stated, oltusum is said to be a quarter of a
line longer in the body, and two thirds in the wings
than pulveratum.

Continental distribution : Sweden.



5. PCECILOSOMA GUTTATUM.

Plate XI, fig. 5, ? .

Tmtliredo guttatum, Fall., Acta, Holm., 1807, 105, 39 (ex parte).

Poecilosoma guttatum, Thorns., Opus. Ent., 289, 4 ; Hym. Scand.,

i, 231, 5; Andre, Species, i,
333; Cat., 42,* 4.

Black, ovate, broad, shining, covered (especially the legs) with a slight
grevish down ; the apex of anterior femora, all the knees, and the tibiae
in front sordid white ; the edge of the pronotum has a thin white line ;
the tegulae are black. Antennae a little longer than the abdomen ; the
third joint is a little longer than the fourth, the fifth, sixth, and seventh
are a very little thicker, the eighth and ninth thinner. The abdominal
segments are very faintly white at the junction, with faint indications
of white between the segments in the middle. The front is smooth,
shining, the sutures are invisible, antennal fovea large, ovate, and
shallow. Wings faintly black, lighter at the apex ; the first tr. cubital
nervure is present, the tr. radial is received in the apical fourth of the
third cubital cellule ; the costa and stigma black, the latter faintly fus-
cous round the edge. The cenchri are very large, oval, white ; blotch
rather small ; the sheath projecting ; hinder calcaria as long as a third
of the basal joint of the tarsus. Claws bifid.

Length 3 3 lines.

This insect is distinguished from submuticum by its
broadly ovate, short body, blackish wings, thicker and
longer antenna?, distinctly bifid claws and longer spurs,
shorter and broader third cubital cellule, and smaller
and much shallower antennal fovea. P. longicorne is
longer, less shining, the antennas thinner and longer,
the frontal sutures distinct, and antennal fovea deeper,
and the calcaria are shorter.

It appears to be a rare species. I have only seen
one British specimen (a ? ). This was taken by Mr.
Fletcher at Worcester.

On the Continent it has only been recorded from
Sweden, but possibly it is overlooked.



216 POECILOSOMA SUBMUTICUM.

6. PGBCILOSOMA LONGICORNE.

Pcecilosoma longicorne, Thorns., Hym. Scand., i, 232, 6 ; Andre,

Species,!, 333; Cat., 42 * 5.

Black, shining, pilose on head and thorax, all the knees and anterior
tibise dirty white, a line on the pronotum clear white, and the abdominal
segments as often as not are marked with longish lateral spots of a
less clear white ; all the segments lined with white at the apices.
Wings hyaline, tinged with fuscous on the apical half; costa and
stigma black. (For Saw, see Plate XXI, Bg. 3.)

5 similar but the antenna) are as long as the body and the legs in
front bear more white.

Length 3 3 lines.

Similar to submuticum but with the body longer and
narrower, the antennae slightly longer and noticeably
thinner with the ? , and distinctly so with the J , these
organs with submuticum not being much longer
than the abdomen, the head is more pilose, the antennal
fovea if anything shorter, and the claws almost bifid.
Thomson describes the claws as "bifid" in longi-
corne, but all my specimens have one tooth shorter
than the other, but still longer than in submuticum.
I am inclined to believe that the relative length of one
of the teeth varies with different specimens. The
first cubital nervure is almost always absent, while in
submuticum it is generally present. The accessory
nervure in hind wing is much appendiculated.

Apparently a common species on Spircea ulmaria.
I bred it along with the larvas of Empliytus calceatus,
but did not have an opportunity of describing the larva.
But see p. 217. The imago appears during May and
June.

Clydesdale, Norwich.

Continental distribution : Sweden.



7. PCECILOSOMA SUBMUTICUM.

Pcecilosoma submuticum, Thorns., Hym. Sc., i, 232, 7 ; Cam.,

Fauna, 20, 3; Andre,
Species, i, 333; Cat., 42,*
6.

Black, half shining, longish ; antennas as long as the abdomen, edge



PCKCILOSOMA EXCISUM. 217

of pronotum, knees, and anterior tibiae white. Abdominal segments
broadly marked with longish white marks, spurs very short, claws with
a minute subapical tooth. The tr. radial nervure is as in guttatum, but
the third cellule is as long as the second, while in guttatum it is shorter.
Cenchri small, antennal fovea large ; sheath short. $ and <.
Length 2 3 lines.

This species may be known by the first tr. cubital
nervure being almost always present, the hinder tibige
and tarsi quite black, or with only a very small white
band on the extreme base, the deep frontal foveaB,
short spurs, and claws with a small subapical tooth.
The antennal joints are more distinctly separated than
in yntf'tti'.iii. (For Saw, see Plate XXI, fig. 4.

Ab. a. First tr. cubital nervure absent.
1. First tr. cubital nervure absent and no

middle cellule in the hind wings.
c. Abdomen entirely black.
,, (1. Pronotum black.

Nothing very definite is known regarding the larva
of this common insect. It is frequently bred from
bramble stems, but the larvae in all probability merely
retired there to pass the pupal state. I once bred it
along with the Emphytus calceatus, and hence suspect
that it is attached to Spiraa, upon which I have found
a larva similar to that of calceatus but with black
marks along the sides. (See Plate VII, fig. 1.)

Submuticum is one of the commonest species in the
genus, and is found almost everywhere in June and
late in May.

It is apparently the commonest of the black species
on the Continent, but as they are mixed in most
collections it is impossible to give the distribution with
any exactness.



8. PCECILOSOMA EXCISUM.

Poeciloscma excisum, Thorns., Hym. Sc., i, 233, 8 ; Cam., Fauna,

20; Andre, Species, i, 334, pi.
xx, fig. 2 ; Cat., 42,* 7.
vernalis, Diet., M T. Schw., Ent. Ges., 1868, p. 354?



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