<strong> The Eurasian species of <em> Xyela </ em> (Hymenoptera, Xyelidae): taxonomy, host plants and distribution </ strong>
Author
Blank, Stephan M.
stephan.blank@senckenberg.de.
Author
Shinohara, Akihiko
shinohar@kahaku.go.jp.
Author
Altenhofer, Ewald
stephan.blank@senckenberg.de.
text
Zootaxa
2013
2013-03-18
3629
1
1
106
http://dx.doi.org/10.11646/zootaxa.3629.1.1
journal article
53391
10.11646/zootaxa.3629.1.1
9bac424f-e31f-4780-a976-f4fe3ba62156
1175-5326
5261330
FF47F026-9CB6-4390-B900-130A3DF2B33B
Xyela heldreichii
Blank
,
sp. nov.
Type
locality:
Greece
, Nomos Grevena,
Pindos National Park
E
,
Metsovo N
15 km
,
Mount Blia
.
Xyela julii
:
Csiki 1923: 104
(misidentification).
Description
. Female. Color. Head dark brown to black, usually with indistinct stripes on vertex along upper eye margin extending more or less toward facial and genal orbits, sometimes with indistinct spots lateral to postocellar area and on interantennal area. Antennae brown, ventrally a little paler (
Fig. 58
). Thorax dorsally brown, rarely with more or less distinct pale pattern on mesonotal lobes and mesoscutellum, tegulae pale and largely brown in middle. Thorax ventrally brown, mesosternum laterally yellow. Abdomen brown, tergum 8 and 9+10 laterally and more or less preapical sterna pale brown to yellow. Valvifer 2 yellow, valvula 3 generally darker, preapically infuscate and pale at tip (
Fig. 108
). Legs yellow, coxae brown, upper side of femora and lower side of femora 3 more or less darkened. Wings almost clear, venation and pterostigma pale brown.
Morphology. Fore wing (3.2–)
3.6–4.5 mm
long, 1.60–1.80 times longer than ovipositor sheath, vein Rs+M 200–330 µm long, 2r-m meeting Rs proximal to furcation of Rs1 and Rs2. Synantennomere 3 (490–)610–860 µm long, antennomere 4 (100–)140–180 µm long and 4.0–5.5 times longer than wide distally. Article 3 of maxillary palp 470–610 µm long, 1.45–1.80 times longer than scape and wider than synantennomere 3. OOL: POL = 1.45–1.85: 1. Ovipositor sheath (2.00–)2,30–2,75 mm long, valvula 3 1.95–2.25 times longer than valvifer 2 and 7.0–8.0 times longer than wide at base (
Fig. 108
). Valvula 3 of ovipositor compressed, pale membranous area about as long as basal width of valvula 3, dorsal edge of valvula 3 sloping down to round tip, distally with sensilla field exposed and directed caudally, bearing 3 setae. Ovipositor almost straight and compressed. Valvula 1 with aulax terminating distally, ventral edge sloping up to tip, with 15–16 oblique closely spaced annuli in distal quarter, without serrulae, olistether with 6–7 setae. Left and right valvulae 2 fused along dorsal edge in basal half. Valvula 2 with smooth dorsal margin, tapering in distal half, pale and evenly sclerotized, in distal 0.4 with single sensilla campaniformia, in distal 0.1 with 5 oblique annuli. Posterior tibia (0.80–)
0.90–1.15 mm
long, claws without subapical tooth.
Male. Color. Head yellow with black pattern: narrow black stripes along frontal furrows meeting ocellar and postocellar spot, medial spot on frons, kidney-shaped spots on vertex separate from black postocellar area (
Fig. 59
). Antennae pale brown. Thorax dorsally black, pronotum laterally sometimes with brown spot, lateral and more or less anterior mesonotal lobes with yellow, mesoscutellum with yellow spot, tegulae pale and sometimes brown in middle, mesepisternum largely yellow. Abdominal terga dark brown, hypopygium yellow to brown, usually paler than preceding sterna. Legs pale brown, posterior coxae laterally brown and ventrally brown in basal and pale in distal half. Wing membrane almost hyaline, venation and pterostigma pale brown.
Morphology. Fore wing
3.3–3.7 mm
long, Rs+M 210–250 µm long, 2r-m meeting Rs proximal to furcation of Rs1 and Rs2. Synantennomere 3 640–810 µm long, antennomere 4 (130–)160–200 µm long and 4.5–5.5 times longer than wide distally. Article 3 of maxillary palp 440–530 µm long, 1.45–1.65 times longer than scape and wider than synantennomere 3. OOL: POL = 1.55–1.75: 1. Longitudinal apodeme of basiparamere curved, basal portion in lateral position, harpe about as long as wide in lateral view. Lower ergot on valvular stalk absent. Valviceps 1.50–1.55 times longer than wide on medial lobe, with distinct oblique lateral lamella, proximal lobe of penis valve 0.26–0.30 times as long as valviceps and 0.70–0.75 times as high as medial lobe, excision on lower edge 0.18–0.21 as deep as width of medial lobe, valviceps on medial lobe 1.15–1.25 times wider than on distal lobe, 2 distal flagella present, tip of longer flagellum reaching 0.70–0.75 width of distal lobe (
Fig. 143
). Valviceps with median longitudinal sclerotization present, medial lobe almost symmetric and broad, with 5–9 cone-like sensilla along upper edge and scattered on lateral surface, upper edge between medial and distal lobe with 11–15 setae. Posterior tibia (0.85–)0.90–1.00 mm long, claws without subapical tooth.
Type material
.
Holotype
♀
: “
Greece
: Nom. [
Nomos
]
Grevena
,
Pindos Natl.
[National] Park E,
Metsovo N
15 km
,
Mt. Blia
,
1550 m
NN, 27.–
28.5.2000
,
20°54N
21°12E
, swept from grass below
Pinus heldreichii
, leg.
Blank
&
Kutzscher
”; [red:] “Holotype ♀
Xyela heldreichii
spec. n.
det.
S. M. Blank
2000”.
DEI
.
Paratypes
:
63♀
8♂
,
DEI
,
EJC
,
HNHM
,
MKC
,
MZLS
,
RSME
,
WSC
,
ZSM
.
Etymology
. Like its host plant,
Pinus heldreichii
, the new
Xyela
species
is dedicated to Theodor von Heldreich, who was one of the first modern scientific explorers of the Olympus mountain range, where part of the material of
X. heldreichii
was collected. From 1851, when von Heldreich climbed the Olympus first, until his death in 1902, he contributed more to Greek botany than anybody else before (
Strid 1980
).
Host
plant
.
●
Pinus heldreichii
Chr.
(observation of
two females
ovipositing into staminate cones).
Geographic distribution
.
Albania
,
Greece
(
Fig. 16
).
Remarks
.
Xyela heldreichii
,
X. obscura
and
X. uncinatae
differ from other Palearctic representatives of the
X. julii
group in their (at least predominantly) dark brown or black head. Female
X. heldreichii
are separated from
X. obscura
and
X. uncinatae
by the longer ovipositor and the smaller fore wing: ovipositor ratio, and the brown valvula 3. There are single specimens with a predominantly pale valvula 3, which is not darker than valvifer 2 (possibly not completely colored specimens). In males, the hypopygium is usually paler than the preceding sterna, whereas the sterna are similarly colored in
X. julii
,
X. obscura
and
X. uncinatae
. See also remarks under
X. julii
.
This species has been reported under the name
Xyela julii
by
Csiki (1923)
, who studied
two females
collected at “Mts. Gyalicalums” at
1,650 m
. This name corresponds with the Albanian mountain Gjalicë e Lumës, which lies southeast of
Kukës
(
Friese & Königsmann 1962
).
The larval host plant is without doubt
Pinus heldreichii
. In
Greece
, imagines have been collected several times in
P. heldreichii
woodland either directly from the pine trees or they were swept from the grass below the trees (Mt. Olymp at
2,000 m
; Pindos National Park at
1,750 m
; Vasilitsa Ski Resort at
1,830 m
). On collection sites at lower altitudes
P. heldreichii
was growing intermixed with
P. nigra
(Pindos National Park at
1,550 m
; Mt Smolikas at
1,500 m
). However,
P. nigra
can be excluded as the host plant for two reasons: 1, their staminate cones were too strongly developed at the time of collecting
X. heldreichii
, and the remaining period for a proper development of the larvae would accordingly have been too short; and 2, cones of
P. nigra
presented to
X. heldreichii
females were not accepted for oviposition, but cones of
P. heldreichii
were. Fully developed
Xyela
larvae hatched from
P. heldreichii
cones collected in the Pindos National Park at
1,400 m
and on Mt Smolikas at
1,500 m
in the year 2000. From these samples no imagines hatched in spring 2001, but living larvae were still present in the rearing jars. Possibly, larvae of
P. heldreichii
diapause at least two years as is known for the other European subalpine
Xyela
species
,
X. alpigena
and
X. obscura
.
Pinus heldreichii
(panzer pine, white-bark pine) occurs in the dry and usually rocky upper zone of limestone mountains in the western part of the Balkan Peninsula (
Friese & Königsmann 1962
, Polunin 1988,
Kindel 1995
). A disjunct population is present in southeastern
Italy
(
Adamović 1909
,
Kindel 1995
), but no
Xyela
material was available from there. In
Greece
, single
P. heldreichii
trees are found at ca
1,000 m
. There and at higher altitude it grows intermixed with
P. nigra
,
P. heldreichii
becoming dominant from ca
1,700 m
. Above
2,000 m
it forms an open woodland. Between 2,300 and
2,500 m
, the
P. heldreichii
is reduced to krummholz which gradually becomes lower and more scattered (
Strid 1980
). Within the
P. heldreichii
zone,
X. heldreichii
has been collected from
1,400 to 2,000 m
. It is possibly absent at lower altitudes as no larvae were found in 4 samples of staminate cones collected on the Mt. Olympus range between 900 and
1,300 m
.