www.geologicacarpathica.sk
GEOLOGICA CARPATHICA, DECEMBER 2010, 61, 6, 463—468 doi: 10.2478/v10096-010-0028-x
New male pelecinid wasps (Hymenoptera: Pelecinidae) from
the Yixian Formation of western Liaoning (China)
HUA FENG, CHUNGKUN SHIH, DONG REN and CHENXI LIU
College of Life Science, Capital Normal University, 105 Xisanhuanbeilu, Haidian District, Beijing, 100048 P.R.China;
rendong@mail.cnu.edu.cn
(Manuscript received April 22, 2010; accepted in revised form June 10, 2010)
Abstract: Two new genera and species Abropelecinus annulatus gen. et sp. nov. and Azygopelecinus clavatus gen. et
sp. nov., placed in the subfamily Iscopininae of the family Pelecinidae, are described and illustrated. Sinopecinus viriosus
Zhang, Rasnitsyn & Zhang, 2002 are re-described. All these male specimens were collected from the Yixian Formation
of Beipiao City, Liaoning Province, northeastern China. A key to the male species of the subfamily Iscopininae is given.
In addition, sexual dimorphism in Pelecinidae and the paleoclimate of the Yixian Formation are briefly discussed.
Key words: Pelecinidae, Proctotrupoidea, Hymenoptera, new taxa, Yixian Formation, China.
Introduction
Pelecinidae, a family with only one extant genus, Pelecinus
Latreille, 1802, belongs to the superfamily Proctorupoidea
(Rasnitsyn 1980, 1988; Masner 1993). Pelecinus contains
three extant species distributed in North and South Americas
(Johnson & Musetti 1999). Pelecinids are highly sexually di-
morphic and the sexes can easily be recognized by the form of
metasoma. The metasoma of extant males, usually with seven
segments but only six visible externally, is strongly clavate or
tubular (Johnson & Musetti 1998) and less than twice as long
as the head and mesosoma combined. In contrast, the metaso-
ma of the females, usually with six segments visible, is linear
or tubular and more than twice as long as the head and meso-
soma combined. In North America, the females are commonly
found, but the males on the other hand are very rarely seen
(Brues 1928; Johnson & Musetti 1998, 1999). Brues believed
that Pelecinus is most probably an example of geographical
parthenogenesis and its reproduction mode, either bisexual or
parthenogenetic, may be related to climate conditions.
Twelve fossil genera with 43 species within this family
have been described (Brues 1933; Kozlov 1974; Johnson
1998; Engel 2002; Zhang et al. 2002; Zhang & Rasnitsyn
2004; Zhang 2005; Zhang & Rasnitsyn 2006; Engel & Grimal-
di 2006; Duan & Cheng 2006; Rasnitsyn 2008; Shih et al.
2009; Liu et al. 2009, 2011). Like the extant male pelecinid
wasp, the males of fossil pelecinids are also quite rare. Only
eight of the 43 described fossil species were erected on the ba-
sis of male specimens: four from Baissa, Russia, one from the
Baltic, one from New Jersey, one from Shar Teg, Mongolia,
and one from Beipiao, China. They are summarized in
Rasnitsyn (2008) and Shih et al. (2009). Three of these are
placed in the subfamily Pelecininae: Pelecinopteron tubuli-
forme Brues, 1933 (Engel, 2002) from Baltic amber; Protope-
lecinus regularis Zhang & Rasnitsyn, 2004 from Baissa,
Russia; Henopelecinus pygmaeus Engel & Grimaldi, 2006,
from New Jersey amber. The remaining five are placed in the
subfamily Iscopininae: Iscopinus baissicus Kozlov, 1974,
I. simplex Zhang & Rasnitsyn, 2004 and ?I. suspectus Zhang
& Rasnitsyn, 2004, all from Baissa, Russia; Sinopelecinus
viriosus Zhang, Rasnitsyn & Zhang, 2002 from Beipiao, Chi-
na, and Praescopinus excellens Rasnitsyn, 2008 from south-
western Mongolia, Shar Teg.
Recently we collected a total of 112 fossil specimens of
pelecinids, 14 of which were males, from the Yixian Forma-
tion, Huangbanjigou, near Chaomidian Village, Shangyuan
Township, Beipiao City, Liaoning Province (Fig. 1), China.
Because the forewing venation is comparatively reduced and
the ‘X’ pattern formed by 2r-rs, Rs, Rs
1
and Rs
2
is absent, we
assigned the fossils to the subfamily Iscopininae. We de-
Fig. 1. Index map showing section localities of the Yixian Formation
in Jinzhou—Yixian area, western Liaoning (after Ren et al. 1997).
I – Sihetun section; II – Huangbanjigou section; III –Mashenmiao-
Songbahu section.
464
FENG, SHIH, REN and LIU
scribe two new genera with one new species each, Abrope-
lecinus annulatus gen. et sp. nov. and Azygopelecinus clava-
tus gen. et sp. nov. Using information and data from the new
fossils, we re-describe Sinopecinus viriosus Zhang, Rasnitsyn
& Zhang, 2002.
The exact age of the Yixian Formation is still undecided.
There are three main opinions: the Late Jurassic (Ren et al.
1997; Zheng et al. 2003); the Late Jurassic—Early Cretaceous
(Chen et al. 2004; Wang et al. 2004, 2005) and the Early
Cretaceous (Swisher et al. 1999; Zhou et al.). By comparing
the Yixian biota with the Solnhofen biota of Germany, the
Purbeck biota from England and Late Jurassic Terori-type
and Ryoseki-type floras from Japan, Wang et al. (Wang et al.
2005) considered the age of the Yixian Formation to be the
Late Jurassic to Early Cretaceous (Late Tithonian to the
Berriasian).
Materials and methods
The fossil specimens are deposited in the Key Laboratory
of Insect Evolution & Environmental Changes, Capital Nor-
mal University Beijing, China (CNU). They were examined
using Leica MZ12.5 dissecting microscopes and illustrated
with the aid of an attached drawing tube. The final line illus-
trations were produced with Photoshop CS graphic software.
Photos were taken with a Nikon DXM1200C digital camera.
Morphological terminology and the system used here follow
that of Mason (1986), Johnson & Musetti (1999), and Zhang
& Rasnitsyn (2004).
The following standards were used for measurements:
body length was measured from the apex of the head to the
apex of the metasoma; head length from the vertex to the base
of the head; head width at the maximal width of the head; me-
sosoma, metasoma, trochanter, femur, tibia, at the midline;
wing length, from the base to the apex, wing width, at the
maximal width of the wing. All measurements are in milli-
meters (mm).
Systematic paleontology
Order: Hymenoptera Linnaeus, 1758
Suborder: Apocrita Gerstäcker, 1867
Superfamily: Proctotrupoidea Latreille, 1802
Family: Pelecinidae Haliday, 1840
Subfamily: Iscopininae Rasnitsyn, 1980
Genus: Abropelecinus gen. nov.
T y p e s p e c i e s: Abropelecinus annulatus sp. nov.
E t y m o l o g y: The generic name is a combination of the
Greek prefix ‘abro’ (graceful) and Pelecinus (the type genus
of this family). Gender masculine.
D i a g n o s i s: Male, antenna with 13 segments. Forewing
with only two veins present (C and R). Metasoma with the
seventh segment oblong, slightly acute apically (sometimes
tergum and sternum separated to an extent).
S p e c i e s i n c l u d e d: Type only.
Fig. 2. Abropelecinus annulatus gen. et sp. nov., photograph of ho-
lotype, part and counterpart. A – CNU—HYM—LB2006046C; B –
CNU—HYM—LB2006046P.
Abropelecinus annulatus sp. nov.
Figs. 2 and 3
E t y m o l o g y: The species name is derived from the Latin
‘annulatus’, meaning ringed.
H o l o t y p e: CNU—HYM—LB2006046-P & -C (part and
counterpart). A complete insect except for missing part of legs.
P a r a t y p e: CNU—HYM—LB2006052-P & -C (part and
counterpart); CNU—HYM—LB2006067-P & -C (part and coun-
terpart); CNU—HYM—LB2006075-P & -C (part and counter-
part); CNU—HYM—LB2006076; CNU—HYM—LB2006077;
CNU—HYM—LB2006079; CNU—HYM—LB2006083; CNU—
HYM—LB2006084-P & -C (part and counterpart).
Fig. 3. Abropelecinus annulatus
gen. et sp. nov., line drawing of ho-
lotype. CNU—HYM—LB2006046C.
465
NEW MALE PELECINID WASPS FROM WESTERN LIAONING (CHINA)
T y p e l o c a l i t y a n d h o r i z o n: Collected from Huang-
banjigou, near Chaomidian Village, Shangyuan Township,
Beipiao City, Liaoning Province, China, the Yixian Forma-
tion, Late Jurassic to Early Cretaceous.
D i a g n o s i s: Same as for the genus.
D e s c r i p t i o n: Male; female unknown. Body length
10.9 mm; Head broadly transverse, length 0.8 mm and width
1.1 mm; compound eyes large, nearly oval; antenna with 13
segments, filiform but strong and thick. In both antennae, seg-
ments from 7 to 11 are preserved in coils. Of nine specimens
collected, six have complete antennae preserved: four have
antennae coiled, but two have antennae preserved straight.
Scape trapezoid, thinner basally and thicker apically, apex
slightly wider than pedicel and flagellum; pedicel shorter than
half of scape, rectangular, slightly wider than long; flagellom-
eres cylindrical, the first flagellomere longer than scape and
pedicel combined, subsequent ones also cylindrical and
homonomous, with slightly decreasing length, but terminal
flagellomere longer than the preceding one and acute.
Mesosoma length 2.9 mm, width 1.3 mm. Pronotum short
dorsally. Mesoscutum large. Scutellum semicicular. Propo-
deum comparatively narrow, trapezoid. Metanotum and pro-
podeum with irregular and coarse reticulate sculpture.
Forewing narrow and long, with only two veins (C and R)
visible, R straight; pterostigma elongate and narrow, taper-
ing to a point on anterior wing margin; M + Cu indistinct and
weak. Hind wing slightly shorter than half length of forew-
ing, with only C present.
Fore leg with only right coxa and partial femur are pre-
served. Mid leg discernible, mesocoxa comparatively small,
mesotrochanter subrectangular, mesofemur and mesotibia
incomplete but thinner than corresponding parts of hind leg,
mesotarsus with only four segments preserved, basitarsus
longer than remaining combined. Hind leg incomplete and
distinctly paler than antennae, metacoxa big, round; metatro-
chanter trapezoid, metafemur slightly widened, metatibia
narrow basally and gradually widened apically, slightly
longer than metafemur, metatarsus narrow but incomplete.
Metasoma slender, length of 7.2 mm is about 7/10 of body
length, and slightly paler than antennae. Seven segments vis-
ible, lengths are 0.8 mm, 0.8 mm, 0.8 mm, 0.8 mm, 1.1 mm,
1.3 mm and 1.6 mm; first and second metasomal segments
alike and nearly square; third, fourth and fifth metasomal
segments rectangular and becoming narrower; fifth metaso-
mal segment nearly 3 times as long as wide; sixth metasomal
segment trapezoid, narrowest basally of the entire metasoma;
seventh metasomal segment approximately as long as sixth
one and sternum acute apically; length ratio of metasomal
segments is 1.0 : 1.0 : 1.0 : 1.0 : 1.4 : 1.6 : 2.0.
Genus: Azygopelecinus gen. nov.
T y p e s p e c i e s: Azygopelecinus clavatus sp. nov.
E t y m o l o g y: The generic name is a combination of the
Greek prefix ‘azygo’ (odd) and Pelecinus (the type genus of
this family). Gender masculine.
D i a g n o s i s: Male, antenna with 15? segments. Forewing
with only two veins distinct (C and R), 2r-rs issuing medial 1/3
of pterostigma, Rs short. M + Cu discernible, straight. First
metasomal segment thin and rectangular, second and third ones
nearly triangular, very narrow basally, fourth to sixth ones near-
ly trapeziform, last metasomal segment short triangular.
S p e c i e s i n c l u d e d: Type only.
Azygopelecinus clavatus sp. nov.
Figs. 4 and 5
E t y m o l o g y: The species name is derived from the Latin
‘clavatus’, meaning clavate.
H o l o t y p e: CNU—HYM—LB2006033. A complete insect
except for missing part of legs.
Fig. 5. Azygopelecinus clavatus gen.
et sp. nov., line drawing of holotype,
CNU—HYM—LB2006033.
Fig. 4. Azygopelecinus clavatus gen. et sp. nov., photograph of ho-
lotype. CNU—HYM—LB2006033.
466
FENG, SHIH, REN and LIU
T y p e l o c a l i t y a n d h o r i z o n: Collected from Huang-
banjigou, near Chaomidian Village, Shangyuan Township,
Beipiao City, Liaoning Province, China, the Yixian Forma-
tion, Late Jurassic to Early Cretaceous.
D i a g n o s i s: Same as for the genus.
D e s c r i p t i o n: Male; female unknown. Body size small,
6.4 mm. Head medium-sized, length 0.6 mm, width 1.0 mm,
vertex narrow; compound eyes unclear; antenna with 15? seg-
ments, filiform, paler than mesosoma but scape and terminal
segment darker than others; scape trapezoid, thinner apically
and thicker basally, pedicel short, nearly half of scape, rectan-
gular, flagellomeres cylindrical, first flagellomere as long as
scape and pedicel combined, subsequent flagellomeres also
cylindrical and homonomous, with slightly decreasing length,
terminal flagellomere slightly expanded apically.
Mesosoma length 1.8 mm, width 1.0 mm. Pronotum com-
paratively long dorsally. Propodeum with irregularly coarse-
ly reticulate.
Forewing length 2.7 mm, width 1.1 mm, with venation
pale, two veins (C and R) darker and clearer, R straight, 2r-rs
issuing nearly midpoint of pterostigma, Rs short, almost
spectral, oblique apicad. M+Cu discernible and straight.
Pterostigma elongate and narrow, tapering to a point on ante-
rior wing margin.
Fore leg with only coxa partially preserved. Mid leg discern-
ible but with contour not clear, thinner than hind leg, pale-yel-
low like hind leg, but both paler than mesosoma. Hind leg
incomplete, metacoxa big, trapeziform; metafemur slightly wid-
ened, metatibia as long as metafemur, narrow basally and grad-
ually widened apically, metatarsus narrow and incomplete.
Metasoma slender, 6/10 of body length; 7 segments visible,
lengths are 0.5 mm, 0.7 mm, 0.7 mm, 0.6 mm, 0.6 mm, 0.5 mm
and 0.4 mm; first metasomal segment thinner than other seg-
ments, rectangular, approximately 2.4 times as long as wide;
second and third metasomal segments nearly triangular, very
narrow basally; fourth to sixth metasomal segments nearly tra-
peziform and gradually broadening; last metasomal segment tri-
angular, shortest, joining broadly with the former; length ratio
of metasomal segments is 1.0 : 1.4 : 1.4 : 1.2 : 1.2 : 1.0 : 0.4.
Genus: Sinopelecinus Zhang, Rasnitsyn & Zhang, 2002
T y p e s p e c i e s: Sinopelecinus viriosus Zhang, Rasnitsyn
& Zhang, 2002.
R e v i s e d d i a g n o s i s: Male, antenna with 15 segments,
forewing with two veins (C and R), R slightly bent; 2r-rs ob-
lique apicad and slightly longer than width of pterostigma;
Rs short, almost spectral; M + Cu distinguishable and
straight, bearing short rudiments of free M and 1cu-a. Meta-
soma with 1—6 segments nearly parallel-sided, rectangular,
last segment triangular.
S p e c i e s i n c l u d e d: Type only.
Sinopelecinus viriosus Zhang, Rasnitsyn & Zhang, 2002
Figs. 6 and 7
M a t e r i a l:
CNU—HYM—LB2006026;
CNU—HYM—
LB2006078-P & -C (part and counterpart); CNU—HYM—
LB2006082; CNU—HYM—LB2006042.
Fig. 6. Sinopecinus viriosus Zhang, Rasnitsyn & Zhang 2002, pho-
tograph of CNU—HYM—LB2006026.
Fig. 7. Sinopecinus viriosus Zhang, Rasnitsyn & Zhang 2002, line
drawing of CNU—HYM—LB2006026.
R e d e s c r i p t i o n: Male; female unknown. Body length
9.8 mm. Head medium-sized, length 0.9 mm and width
1.3 mm; compound eyes nearly oval; antenna with 15 seg-
ments, filiform but very strong, slightly longer than the head
and mesosoma combined, scape trapezoid, thicker apically
and thinner basally, cupped apically, pedicel short, inserted
in scape, flagellomeres cylindrical and homonomous, with
slightly decreasing length and width.
467
NEW MALE PELECINID WASPS FROM WESTERN LIAONING (CHINA)
Mesosoma length 3.0 mm, width 1.5 mm. Pronotum com-
paratively long dorsally. Propodeum well produced above
metacoxa, with irregular and coarse reticulate sculpture.
Forewing length 4.2 mm. C straight, R slightly bent, darker
than C; pterostigma elongate and narrow, tapering to a point
on anterior wing margin; 2r-rs arising in middle 1/3 of
pterostigma, oblique apicad, two times as long as pterostig-
mal width; Rs short; M + Cu discernible and straight, bearing
short rudiments of free M and 1cu-a. Hind wing shorter than
half of forewing.
Fore legs not well preserved with only procoxa and protro-
chanter complete, procoxa oblong, protrochanter nearly as
long as procoxa; mesocoxa slightly wider than procoxa, elon-
gate oval; mesotrochanter smaller than mesocoxa, mesofemur
stick-like, not gradually widened apically, mesotibia shorter
and thinner than mesofemur, stick-like, slightly widened api-
cally, mesotarsus incomplete, only 4 segments preserved, me-
sobasitarsus longest tarsomere; metacoxa oval, bigger than
mesocoxa, metatrochanter as long as mesotrochanter, metafe-
mur slightly longer than mesofemur, stick-like, not gradually
widened apically, metatibia stick-like, just slightly widened
apically, metatarsus thin, 5 segmented, metabasitarsus longest
tarsomere, about twice as long as second metatarsomere, but
shorter than half metatibia, fourth tarsomere shortest.
Metasoma slender and elongate, 6/10 of body length, 7 seg-
ments visible, stick-like, lengths are 1.1 mm, 0.8 mm,
0.9 mm, 0.7 mm, 1.0 mm, 0.7 mm and 0.7 mm; 1—6 segments
nearly parallel-sided, rectangular. First metasomal segment
slightly more than 2 times as long as wide, fifth one 2.2 times
as long as wide, seventh one triangular, apex not acute; length
ratio of metasomal segments is 1.0 : 0.7 : 0.8 : 0.6 : 0.9 : 0.6 : 0.6.
Remarks
Although different from other known pelecinids, the
wasps described here are undoubtedly members of the Pele-
cinidae according to their metasoma and wing venation
(Zhang & Rasnitsyn 2004). Zhang and Rasnitsyn have erect-
ed three genera (Sinopelecinus, Eopelecinus, Scorpiopeleci-
nus) mainly based on whether the forewing venation was
complete or reduced and the configuration of the first three
segments of the metasoma. We follow them and adopt the
shape of metasoma as a key diagnostic feature. These two
new genera and species are significantly different from other
‘male’ species.
Key to male species of the subfamily Iscopininae:
1. Forewing with r closed
..................................................
2
Forewing with r opened or absent
..................................
5
2 (1). Forewing ‘Rs
2
’ present
................................................
...............................
Iscopinus baissicus Kozlov, 1974
Forewing ‘Rs
2
’ absent
..............................................
3
3 (2). Forewing m-cu absent
.................................................
...............
Iscopinus simplex Zhang & Rasnitsyn, 2004
Forewing m-cu present
.............................................
4
4 (3). Forewing first abscissa Rs shorter than that of M
........
.
..........
?Iscopinus suspectus Zhang & Rasnitsyn, 2004
Forewing first abscissa Rs longer than that of M
......................
Praescopinus excellens Rasnitsyn, 2008
5 (1). Antenna with 13 segments; forewing with only C and R
veins present
.................................................................
..................... Abropelecinus annulatus gen. et sp. nov.
Antenna with 15 segments; forewing with C, R veins
and 2r-rs crossvein, Rs short
......................................
6
6 (5). Metasomal 6
th
segment trapezoid, its basal point nar-
rowest, 7
th
segment slightly acute apically
...................
......................
Azygopelecinus clavatus gen. et sp. nov.
Metasomal 6
th
segment same as the preceding one but
shorter, 7
th
segment triangular ...................................
.. Sinopelecinus viriosus Zhang, Rasnitsyn & Zhang, 2002.
Discussion
Among fossil Pelecinidae, only Pelecinopteron Brues,
1933 and Sinopelecinus Zhang, Rasnitsyn & Zhang, 2002
were described based on both male and female specimens
preserved in Baltic ambers and in Beipiao, China respective-
ly. All other known species have been based on either male
or female specimens only, and none of these have subse-
quently been associated. We initially hoped that we could
match our new male specimens with already described ‘fe-
male’ species from the same horizon and locality. But due to
the low numbers of pelecinid fossils and their state of preser-
vation, we could not associate the fossil male and female
specimens with sufficient degree of confidence. Therefore,
we tentatively erect two new genera and species.
In extant male pelecinids, the metasoma is composed of
seven segments, but only six are visible externally (Johnson &
Musetti 1999). Up to date, all reported fossil male pelecinids
have metasoma with seven distinct segments, but the 7
th
meta-
somal segment is variable in shape. In Pelecinopteron and
Henopelecinus it is falcate (Engel 2002; Engel & Grimaldi
2006). In Protopelecinus, the 7
th
metasomal segment is the
same as the preceding one but shorter (Zhang & Rasnitsyn
2004). In Iscopinus and Sinopelecinus, the 7
th
segment is as
wide as the 6
th
basally and gradually tapering apicad (Kozlov
1974; Zhang et al. 2002). We assume that the shape of the ter-
minal segment may be related to mating behavior which may
result in further speciation. If this is true, the terminal segment
may be important in taxonomic studies of male pelecinids.
In the Beipiao locality during the Late Jurassic to Early
Cretaceous, the paleoenvironment comprised large lakes sur-
rounded by hygrophilous plants, dominated by shore-line
equisetales and filicales. The climate was warm and humid
with many arboreal gymnosperms, such as ginkgoes and co-
nifers. This area also had forests on high mountains which
were distant from the lake shore under a temperate but arid
microclimate (Zhang H.C. & Zhang J.F. 2000). Brues (1928)
highlighted Pelecinus polyturator as an example of geo-
graphic parthenogenesis: tropical, or at least warmer climate
populations are bisexual whereas populations in more tem-
perate climates consist of only females. Johnson & Musetti
(1998 and 1999) analysed the data on distribution of genders
separately. The populations in the USA and Canada are pri-
marily thelytokous. Males account for approximately 4 % of
468
FENG, SHIH, REN and LIU
the collected specimens. The nearest populations in northern
Mexico have males occurring at the same, or higher frequen-
cy as in the rest of tropical America. They partially support-
ed Brues’ point of view.
In our collection of 14 male and 98 female pelecinid fossils
from the Yixian Formation, the males account for approxi-
mately 12.5 % of all collected specimens. Therefore, we pro-
pose that the composition of male pelecinids supports Zhang
et Zhang’s point of view about paleoenvironment and consis-
tent with other fossil insects found in this locality and horizon.
Acknowledgments: We are sincerely grateful to Wang
Yongjie (Department of Entomology, China Agricultural
University), Gao Taiping, Yue Yanli, Yang Xiaoguang (Col-
lege of Life Sciences, Capital Normal University) and Chen
Huayan (College of Natural Resources and Environment,
Southern China Agricultural University) for their valuable
comments and suggestion on the manuscript. We also thank
anonymous reviewers for providing valuable suggestions
and comments in improving this manuscript. This work was
supported by the National Natural Science Foundation of
China (No. 40872022, 31071964), Nature Science Founda-
tion of Beijing (No. 5082002) and the PHR20090509 Project
of Beijing Municipal Commission of Education.
References
Brues C.T. 1928: A note on the genus Pelecinus. Psyche 35, 205—209.
Brues C.T. 1933: The parasitic Hymenoptera of the Baltic amber.
Part I. Bernstein-Forschungen. 3, 17—20.
Chen P.J., Wang Q.F., Zhang H.C., Cao M.Z., Li W.B., Wu S.Q. &
Shen Y.B. 2004: Discussion on the stratotype of Jianshangou
of Yixian Formation. Science in China Series, D, Earth Sciences
34, 883—895 (in Chinese, English abstract).
Duan Y. & Cheng S.L. 2006: A new species of Pelecinidae (Hy-
menoptera: Proctotrupoidea) from the lower Cretaceous Jiufo-
tang Formation of western Liaoning. Acta Palaeont. Sin. 45, 3,
393—398 (in Chinese with English abstract).
Engel M.S. 2002: The fossil pelecinid Pelecinopteron tubuliforme
Brues in Baltic amber (Hymenoptera: Pelecinidae). J. Hy-
menoptera Res. 11, 5—11.
Engel M.S. & Grimaldi D.A. 2006: A diminutive pelecinid wasp in
Cretaceous amber from New Jersey (Hymenoptera: Pelecinidae).
Northeastern Naturalist. 13, 2, 291—297.
Johnson N.F. 1998: The fossil pelecinids Pelecinopteron Brues and
Iscopinus Kozlov (Hymenoptera: Pelecinidae). Proceedings of
the Entomological Society of Washington 100, 1—6.
Johnson N.F. & Musetti L. 1998: Geographic variation of sex ratio
in Pelecinus polyturator (Drury) (Hymenoptera: Pelecinidae).
J. Hymenoptera Res. 7, 48—56.
Johnson N.F. & Musetti L. 1999: Revision of the proctotrupoid ge-
nus Pelecinus Latreille (Hymenoptera: Pelecinidae). J. Natur.
Hist. 33, 1513—1543.
Kozlov M.A. 1974: An Early Cretaceous representative of ichneumon-
flies of the family Pelecinidae (Hymenoptera, Pelecinoidea). Pa-
leontologicheskiy Zhurnal 1974 (1), 144—146 (in Russian).
Li P.X., Cheng Z.W. & Pang Q.Q. 2001: The horizon and age of the
Confuciusornis in Beipiao, western Liaoning. Acta Geol. Sin.
75, 1, 1—13 (in Chinese, English abstract).
Liu C.X., Shih C.K. & Ren D. 2009: The earliest fossil record of the
wasp subfamily Pelecininae (Hymenoptera: Proctotrupoidea: Pele-
cinidae) from the Yixian Formation of China. Zootaxa 2080, 7—54.
Liu C.X., Gao T.P., Shih C.K. & Ren D. 2011: New findings of pe-
lecinid wasps (Hymenoptera: Proctotrupoidea: Pelecinidae)
from the Yixian Formation of western Liaoning, China. Acta
Geol. Sin. 85, 1, (in print).
Masner L. 1993: Chapter 13. Superfamily Proctotrupoidea. In: Goulet
H. & Huber J.T. (Eds.): Hymenoptera of the world: an identifi-
cation guide to families. Canada Communication Group Pub-
lishing, Canada, Ottawa, 537—557.
Mason W.R.M. 1986: Standard drawing conventions and definitions
for venational and other features of wings of Hymenoptera. Pro-
ceedings of the Entomological Society of Washington 88, 1, 1—7.
Pang Q.Q., Li P.X., Tian S.G. & Liu Y.Q. 2002: Discovery of ostra-
cods in the Dabeigou and Dadianzi Formations at Zhangjiagou,
Luanping County, northern Hebei province of China and new
progress in the biostratigraphic boundary study. Geol. Bull.
China 21, 6, 329—336 (in Chinese, English abstract).
Rasnitsyn A.P. 1980: Origin and evolution of the Hymenoptera.
Trans. Paleont. Inst., Acad. Sci. USSR 174, 1—192 (in Russian).
Rasnitsyn A.P. 1988: An outline of evolution of the hymenopterous
insects (order Vespida). Oriental Insects 22, 115—145.
Rasnitsyn A.P. 2008: Hymenopterous insects (Insecta: Vespida) in
the Upper Jurassic deposits of Shar Teg, SW Mongolia. Rus-
sian Entomol. J. 17, 3, 299—310.
Ren D., Guo Z.G., Lu L.W., Ji S.A., Tang F., Jin Y.G., Fang X.S. &
Ji Q. 1997: A further contribution to the knowledge of the Up-
per Jurassic Yixian Formation in Western Liaoning. Geol. Rev.
43, 449—459 (in Chinese, English abstract).
Ren D., Gao K.Q., Guo Z.G., Tan J.J. & Song Z. 2002: Stratigraph-
ic division of the Jurassic in the Daohugou area, Nengcheng,
Inner Mongolia. Geol. Bull. China 21, 8—9, 584—591.
Shih C.K., Liu C.X. & Ren D. 2009: The earliest fossil record of pele-
cinid wasps (Insecta: Hymenoptera: Proctotrupoidae: Pelecinidae)
from Inner Mongolia, China. Entomol. Soc. Amer. 102, 1, 20—38.
Swisher C.C., Wang Y.Q., Wang X.L., Xu X. & Wang Y. 1999:
Cretaceous age for the feathered dinosaurs of Liaoning, China.
Nature 400, 58—61.
Wang W.L., Zhang L.J., Zheng S.L., Zheng Y.J., Zhang H., Li Z.T. &
Yang F.L. 2004: A new study on the stratotype and biostratigra-
phy of the Yixian stage in Yixian – Beipiao region, Liaoning
– establishment and study of stratotypes of the Yixian stage.
Acta Geol. Sin. 78, 4, 433—447 (in Chinese, English abstract).
Wang W.L., Zhang L.J., Zheng S.L., Ren D., Zheng Y.J., Zhang H.,
Li Z.T. & Yang F.L. 2005: The age of the Yixian stage and the
boundary of Jurassic Cretaceous – the establishment and
study of stratotypes of the Yixian stages. Geol. Rev. 51, 3,
234—242 (in Chinese, English abstract).
Zhang H.C. & Rasnitsyn A.P. 2004: Pelecinid wasps (Insecta: Hy-
menoptera: Proctotrupoidea) from the Cretaceous of Russia
and Mongolia. Cretaceous Research 25, 807—825.
Zhang H.C. & Zhang J.F. 2000: Xyelid sawflies (Insecta, Hy-
menoptera) from the upper Jurassic Yixian formation of west-
ern Liaoning, China. Acta Palaeont. Sin. 39, 4, 476—492.
Zhang H.C., Rasnitsyn A.P. & Zhang J.F. 2002: Pelecinid wasps (In-
secta: Hymenoptera: Proctotrupoidea) from the Yixian Formation
of western Liaoning, China. Cretaceous Research 23, 87—98.
Zhang J.F. 2005: Eight new species of the genus Eopelecinus (Hy-
menoptera: Proctotrupoidea) from the Laiyang Formation,
Shandong Province, China. Paleont. J. 39, 4, 417—427.
Zhang J.F. & Rasnitsyn A.P. 2006: New extinct taxa of Pelecinidae
sensu lato (Hymenoptera: Proctotrupoidea) in the Laiyang For-
mation, Shandong, China. Cretaceous Research 27, 684—688.
Zheng S.L., Zheng Y.J. & Xing D.H. 2003: Characteristics, age and
climate of Late Jurassic Yixian flora from western Liaoning. J.
Stratigraphy 27, 3, 233—241 (in Chinese, English abstract).
Zhou Z.H., Barrett P.M. & Hilton J. 2003: An exceptionally pre-
served lower Cretaceous ecosystem. Nature 421, 807—814.