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280
Paleontological Journal, Vol. 39, No. 3, 2005, pp. 280–283. Translated from Paleontologicheskii Zhurnal, No. 3, 2005, pp. 55–58.
Original Russian Text Copyright © 2005 by Vasilenko.
English Translation Copyright © 2005 by
åÄIä “Nauka
/Interperiodica” (Russia).
INTRODUCTION
The assemblage of Late Mesozoic Odonata from
eastern Transbaikalia is rather poor in both higher and
lower taxa, unlike assemblages of a similar age in Ger-
many (Solnhofen) and England, where Odonata
remains are abundant and diverse. There are four large
stratigraphic units recognized in the Mesozoic conti-
nental section of eastern Transbaikalia: Shadoron
Group (
J
2–3
), Unda-Daya Group (
J
3
), Turga Formation
(
J
3
–K
1
), and Kuti Formation (
K
1
). Odonata remains are
known only from volcanic sedimentary rocks of the
Unda-Daya Group and the Turga Formation. The Odo-
nata assemblages of these stratigraphic units are strik-
ingly different at the subordinal level.
Odonata of the suborder Anisozygoptera, three spe-
cies in three genera of the extinct family Isophlebiidae,
are characteristic of the Unda-Daya Group. Organic
remains often form single-taxon oryctocenoses in the
volcanic sedimentary rocks of the Unda-Daya Group.
These are, for example, oryctocenoses formed by
horsetails (
Equisetites
sp.), moss (
Muscites
sp.), lyco-
pods (
Lycopodites
sp.), and body fragments and cara-
paces of tadpole shrimps
Prolepidurus
sp. In some
oryctocenoses, larvae and imagoes of isophlebiid Odo-
nata form either sheet single-taxon assemblages or dis-
persed assemblages, which contain remains of horse-
tails or tadpole shrimps. Other animals or plants do not
form separate assemblages. According to accepted
reconstructions, deposits of the Unda-Daya Group
were accumulated in high-mountain caldera lakes with
sporadic inhabitants, horsetail marshes along the
beaches and beds of water mosses (Sinitza, 1993).
The volcanic sedimentary rocks of the Turga Forma-
tion, which are widespread in Transbaikalia, are poor
(except for the Semen locality) in remains of Odonata,
which are represented by wing fragments or, less com-
monly, by larvae of Anisoptera, dominated mostly by
members of the family Aeschnidiidae or, in much rarer
cases, by Aeschnidae. The Odonata of the Turga Forma-
tion are still poorly known; however, preliminary results
show that Aeschnidiidae are represented by at least three
genera in the Turga oryctocenoses. Various lakes that
experienced periodic change of regime have been recon-
structed for the Turga Formation (Sinitza, 1975).
The first organic remains from insect-bearing beds
of the Chernovskie Kopi locality were collected by Si-
nitza in the mid-1980s. The largest collection of insect
remains from this locality (over 500 specimens, repre-
senting 13 insect orders) was collected between 1993
and 1995. Although Orthoptera dominate numerically
in this collection, the remains of aquatic insects gener-
ally outnumber those of terrestrial insects (Sinitshen-
kova, 2000). Odonata are of sporadic occurrence.
Identification of the collection has shown that oryc-
tocenoses of this locality cannot be assigned to any of
the stratigraphic levels recognized in eastern Trans-
baikalia, contain a mixed assemblage of fossil insects
(Sinitza, 1995; Sinitshenkova, 2000), and are consid-
ered to be transitional between the Unda-Daya Group
and the Turga Formation (Sinitza, 1995).
Subsequent collections have shown the same pattern
of domination despite an increased relative abundance
of beetles and cockroaches.
In 2004, a total of 15 Odonata remains were known
from the locality of Chernovskie Kopi, most of them
represented by wing fragments buried along with leaf
flora (conifer and ginkgophyte leaves). Only one poorly
preserved anisopteran-like larva has been found in a
bed with plant debris.
Although this collection of Odonata is small, it
shows an unusual diversity (uncommon in eastern
Transbaikalian oryctocenoses) and includes members
of the dominant suborder Anisoptera: Gomphae-
schnidae (
Gomphaeschna sibirica
: Bechly
et al.
, 2001)
New Damselflies (Odonata: Synlestidae, Hemiphlebiidae)
from the Mesozoic Transbaikalian Locality of Chernovskie Kopi
D. V. Vasilenko
Chita State University, ul. Aleksandro-Zavodskaya 30, Chita, 672039 Russia
e-mail: lab@palaeoentomolog.ru
Received March 26, 2004
Abstract
—Two new genera and two new species,
Gaurimacia sophiae
gen. et sp. nov. (Synlestidae) and
Mer-
situria ludmilae
gen. et sp. nov. (Hemiphlebiidae), are described from the Mesozoic locality of Chernovskie
Kopi in eastern Transbaikalia. The Odonata assemblage of Chernovskie Kopi is analyzed.
Key words
: new species and genera, damselflies, Insecta, Odonata, Synlestidae, Hemiphlebiidae, Mesozoic,
Transbaikalia, Chernovskie Kopi.
PALEONTOLOGICAL JOURNAL
Vol. 39
No. 3
2005
NEW DAMSELFLIES (ODONATA: SYNLESTIDAE, HEMIPHLEBIIDAE) 281
and as yet undescribed Aeschnidiidae and Aeshnidae.
New members of the families Synlestidae and Hemi-
phlebiidae (suborder Zygoptera) are described below.
Representatives of these families are extremely rare in
the fossil record and are known mainly from modern
faunas, hence, the significance of the Odonata assem-
blage of Chernovskie Kopi.
SYSTEMATIC PALEONTOLOGY
Family Synlestidae Tillyard, 1917
(=Chlorolestidae Fraser, 1960)
Representatives of this extant family have low abun-
dance and limited distributions; they occur in South
Africa, Australia, and South America. The assignment
of the specimen under description to the family Synles-
tidae is based on the shape of the pterostigma and on the
number of cells under it. Eight extant genera with few
species are recognized in this family.
Genus
Gaurimacia
Vasilenko, gen. nov.
Etymology. From the planet Gaurimacia in
The
Star Diaries of Ijon Tichy
by S. Lem.
Type species.
G. sophiae
sp. nov.
Diagnosis.
IR
3
base level with N; anterior mar-
gin of q less than 0.5 times as long as its posterior mar-
gin; A originating slightly proximad of ac.
Species composition. Type species.
Comparison. This genus most closely resem-
bles the genus
Megalestes
Selys, 1862 but differs in the
position of the base of
IR
3
, which is situated at the same
level as N; it differs from the genus
Orolestes
McLachlan, 1895, in addition to the above character, in
the A base being in a position proximal to ac, and from
the genus
Phylolestes
Christiansen, 1947 in the shape
of the discoidal cell.
Gaurimacia sophiae
Vasilenko sp. nov.
Plate 5, fig. 1
Etymology. In honor of the geologist and pale-
ontologist S.M. Sinitza.
Holotype. PIN, no. 4626/461, part and counter-
part of a well-preserved complete wing; Chita Region,
Chita District, left bank of the Ingoda River; Upper
Jurassic–Lower Cretaceous, Doronino Formation,
Chernovskaya transitional sequence.
Description (Fig. 1). The node (N) is situated
at the end of the proximal fifth of the wing; the anteno-
dal complex includes two main antenodal veins cross-
ing both marginal fields;
An
2
is situated at the level of
the arch (arc); vein ac (anal crossing) lies midway
between
An
1
and
An
2
; there are 23 postnodal veins,
some of them coincide with crossveins of the radial
field; the discoidal cell (q) is irregularly shaped, its
anterior distal corner is acute; the subdiscoidal cell (sq)
is narrow, tapering distally and forming an acute angle;
the pterostigma (Pt) is moderately long and broad,
3 times as long as broad and 0.2 times as long as the
distance between its proximal margin and N; there are
six crossveins below the pterostigma; the supporting
vein of the pterostigma (br) is situated proximad of Pt;
the
R
3
base is slightly distad of the midlength between
Pt and N; there are four cells between
IR
2
and
R
3
; the
IR
3
base coincides with sn, the
R
4 + 5
is distad of the
midlength between N and ac; the MA apex is at the Pt
midlength, the CuP apex is at the level of the proximal
margin of Pt; vein
A
1
zigzagged in its distal third.
Duplication of cells between
R
2
and
IR
2
starts below
the distal margin of Pt; between
IR
2
and
R
3
, at the level
of br; between
R
3
and
IR
3
, at the Pt midlength; between
IR
3
and
R
4 + 5
, it starts one cell distad of the level of cell
duplication between
R
3
and
IR
3
; and between
R
4 + 5
and
MA, duplication starts slightly proximad of the proxi-
mal margin of Pt. Vein o (
vena obliqua
) is situated
between
R
3
and
IR
3
below the
IR
2
base;
IR
3
zigzagged
distad of vein o; there is only one row of cells across the
discoidal, cubital, and anal fields. The color pattern of
the wing is uneven. In its basal portion, the wing is pig-
mented from the
R
4 + 5
base to the midlength between
the
R
4 + 5
and
R
3
bases; the apical portion of the wing is
pigmented from the level proximad of Pt.
Measurements, mm. Wing length, 25; wing
maximum width, 7.
Material. Holotype.
An
2
NC
Sc
R + M
An
1
Arc
n
sn
qsq ac
Pn
o
br
Pt
R
2
R
1
IR
2
R
3
IR
3
R
4 + 5
MA CuP A
2
Fig. 1.
Gaurimacia sophiae
sp. nov., holotype PIN, no. 4626/461. Scale bar 2 mm in Figs. 1 and 2.
282
PALEONTOLOGICAL JOURNAL
Vol. 39
No. 3
2005
VASILENKO
Family Hemiphlebiidae Tillyard, 1926
This family is represented by one monotypic genus
in the modern fauna of Australia and, probably, by two
fossil genera,
Parahemiphlebia
and
Cretarchistigma
,
from the Lower Cretaceous of England and Brazil that
were provisionally attributed by their authors to the
superfamily Hemiphlebioidea, without defining their
familial assignment (Jarzembowski
et al.
, 1998).
Bechly (1998) placed the genus
Parahemiphlebia
into
the family Hemiphlebiidae and tentatively assigned the
genus
Cretarchistigma
to the same family.
Representatives of the family are characterized by
small wings, highly reduced venation, and by shifted
crossveins in the first and second wing fields (Belyshev
and Kharitonov, 1977; Jarzembowski
et al.
, 1998).
Genus
Mersituria
Vasilenko, gen. nov.
Etymology. From the planet Mersituria in
The
Star Diaries of Ijon Tichy
by S. Lem.
Type species.
M. ludmilae
sp. nov.
Diagnosis. Node situated at border of basal third
of wing;
R
2
not sharply angular below pterostigma;
IR
2
straight;
A
1
base not zigzagged prior to RS fork; support-
ing vein of pterostigma (br) continuing inner margin of
Pt; subnodal crossvein not coinciding with
IR
3
base.
Species composition. Type species.
1
Plate 5
2
Explanation of Plate 5
Fig. 1.
Gaurimacia sophiae
sp. nov., holotype PIN, no. 4626/461, wing impression,
×
6.
Fig. 2.
Mersituria ludmilae
sp. nov., holotype PIN, no. 4626/462, wing impression,
×
15.
PALEONTOLOGICAL JOURNAL Vol. 39 No. 3 2005
NEW DAMSELFLIES (ODONATA: SYNLESTIDAE, HEMIPHLEBIIDAE) 283
Comparison. This genus differs from the fossil
genera Parahemiphlebia and Cretarchistigma in R2 not
being sharply angular, in the basal position of the node,
and in the coinciding of the supporting vein of Pt and
the inner margin of Pt. It differs from the recent genus
Hemiphlebia Selys, 1868 in IR2 being straight.
Mersituria ludmilae Vasilenko, sp. nov.
Plate 5, fig. 2
Etymology. In honor of the paleoentomologist
L.N. Pritykina.
Holotype. PIN, no. 4626/462, part and counter-
part of incomplete wing; Chita Region, Chita District,
left bank of the Ingoda River; Upper Jurassic–Lower
Cretaceous, Doronino Formation, Chernovskaya tran-
sitional sequence.
Description (Fig. 2). The R3 base is at the level
of the end of the proximal third between Pt and N; the
IR2 base is two cells after the R3 base; R4 + 5 base is dis-
tad of the midlength between the node and the anterior
margin of the discoidal cell; IR3 zigzagged from the
midlength of the pterostigma; the MA apex is slightly
proximad of the pterostigma, the A1 apex is between
the R3 and IR2 bases. There are eight postnodal veins;
the bases of RS crossveins often coincide.
R e m a r k s. The basal portion of the wing is miss-
ing; however, the shape of the discoidal cell is similar to
that in the hind wings of representatives of the family.
Measurements, mm. Length of the fragment,
11; its maximum width, 2.5.
Material. Holotype.
REFERENCES
1. G. Bechly, “New Fossil Dragonflies from the Lower Cre-
taceous Crato Formation of North-East Brazil (Insecta:
Odonata),” Stuttgarter Beitr. Naturk. Ser. B, No. 264,
1−66 (1998).
2. G. Bechly, A. Nel, X. Martínez-Delclós, et al., “A Revi-
sion and Phylogenetic Study of Mesozoic Aeshnoptera,
with Description of Numerous New Taxa (Insecta: Odo-
nata: Anisoptera),” Neue Paläontol. Abhandl. 4, 1–219
(2001).
3. B. F. Belyshev and A. Yu. Kharitonov, Dragonflies
Wings: Handbook for Identification of the Genera of the
Boreal Faunal Realm and Adjacent Areas and the Spe-
cies of the Fauna of the USSR) (Nauka, Novosibirsk,
1977) [in Russian].
4. E. A. Jarzembowski, X. Martínez-Delclós, G. Bechly,
et al., “The Mesozoic Non-Calopterygoid Zygoptera:
Descriptions of New Genera and Species from the Lower
Cretaceous of England and Brazil and Their Phyloge-
netic Significance (Odonata, Zygoptera, Coenagrion-
oidea, Hemiphlebioidea, Lestoidea),” Cretaceous Res.,
No. 19, 403–444 (1998).
5. N. D. Sinitshenkova, “New Mayflies from the Upper
Mesozoic Transbaikalian Locality Chernovskie Kopi
(Insecta: Ephemerida = Ephemeroptera),” Paleontol. Zh.,
No. 1, 63–69 (2000) [Paleontol. J. 34 (1), 68–74 (2000)].
6. S. M. Sinitza, “The Developmental History of Late Cre-
taceous Lake Basins in Eastern Transbaikalia: The His-
tory of Lakes in the Mesozoic, Paleogene, and Neo-
gene,” in Abstracts of Papers of IV All-Union Sympo-
sium on the History of Lakes (Leningrad, 1975), Vol. 1,
pp. 44–50.
7. S. M. Sinitza, “The Jurassic and Lower Cretaceous of
Central Mongolia (Ostracodes: Stratigraphy and Paleo-
reconstruction),” Tr. Sovm. Ross.-Mong. Paleontol.
Eksped., No. 42, 1–235 (1993).
8. S. M. Sinitza, “Chernovskii Paleontological Reserve,” in
Jubilee Edition of the Bulletin of the Chita Polytechnic
Institute (Mosk. Gos. Univ., Moscow, 1995), pp. 70–84
[in Russian].
N
n
sn
q
sq
Pn
br
Pt
R2
R1
IR2
R3IR3R4 + 5
MA CuP A1
Fig. 2. Mersituria ludmilae sp. nov., holotype PIN, no. 4626/462.
