Bull. Natl. Mus. Nat. Sci., Ser. A, 44(1), pp. 1–9, February 22, 2018

Sundaeschna gen. nov. with Descriptions of Two New Species
from Vietnam and Myanmar (Odonata, Anisoptera, Aeshnidae)
Takuya Kiyoshi1, Naoji Katatani2 and Hong Thai Pham3, 4
1

Department of Zoology, National Museum of Nature and Science,
4–1–1 Amakubo, Tsukuba, Ibaraki, 305–0005, Japan
E-mail: kiyoshi@kahaku.go.jp
2
2–29–12 Shoyodai, Nara 631–0007, Japan
3
Vietnam National Museum of Nature, Vietnam Academy of Science and Technology
4
Graduate School of Science and Technology, Vietnam Academy of Science and Technology,
18 Hoang Quoc Viet St, Hanoi, Vietnam(Received 11 October 2017; accepted 20 December 2017)

Abstract Sundaeschna gen. nov. is proposed to accommodate two new species in the family
Aeshnidae. One species, S. cattienensis sp. nov., is described from Dong Nai Province, Vietnam.
Another species, S. tanintharyiensis sp. nov., is described from Tanintharyi Township, Myeik District, Tanintharyi Region, Myanmar. This new genus resembles the genus Sarasaeschna in the tribe
Gomphaeschnini, but is easily distinguished by the structure of the fourth penile segment and by
the pigmental spots on the posterior margins of all wings. Both these new species are recorded
from lowlands, in contrast with Sarasaeschna, whose members generally occur in mountainous
regions. These two new species are easily distinguished from each other by the shape of the male
epiproct.
Key words: Odonata, Aeshnidae, Gomphaeschnini, new genus, new species, Myanmar, Vietnam.

Introduction
The family Aeshnidae currently comprises 54
extant genera (Schorr and Paulson, 2017). This
family was traditionally classiﬁed into two subfamilies, Brachytroninae and Aeschninae (sensu
Steinmann (1997)). The former includes twotribes, Gomphaeschnini and Brachytronini. The
latter includes Aeshnini, Anactini, Gynacanthini,and Polycanthaginini. The tribe Gomphaeschnini
was reconstructed as the basal group of Aeshnidae, based on a morphological cladistic analysis(von Ellenrieder, 2002). This tribe includes four
extant genera (sensu von Ellenrieder, 2002):
Gomphaeschna from North America, Sarasaeschna from India to East Asia, Oligoaeschnafrom the Indomalayan realm, and Linaeschnafrom Borneo (Tsuda, 2000; Kiyoshi et al., 2016).
There are only a small number of scattered

records for the latter three genera, except forsome Sarasaeschna species in East Asia.
In this report, a new genus of the tribe Gomphaeschnini is proposed to accommodate two
new species collected from Vietnam and Myanmar. The new genus resembles Sarasaeschna inbody color patterns but can be distinguished bysome morphological characters, particularly thestraight and posteriorly protruding ﬂagella on the
fourth penile segment of the male. The type
localities for both these species are in lowland
areas of Vietnam (165 m a.s.l.) and Myanmar(17 m a.s.l.), in contrast to most records for Sarasaeschna species in Southeast Asia which haveusually been reported as being present in mountainous regions above 1000 m a.s.l. (Kiyoshi etal., 2016).

T. Kiyoshi et al.

2

Materials and Methods
Morphological terminology mainly follows
Walker (1958). The terms used for abdominal
color pattern are as per Walker (1912).
Abbreviations: S1–S10＝abdominal segments
1–10. AD＝antero-dorsal. MD＝medio-dorsal.
PD＝postero-dorsal. AL＝antero-lateral. ML＝medio-lateral, PL＝postero-lateral. AML is acombination of AL and ML.
Description
Sundaeschna Kiyoshi and Katatani gen. nov.
Type species: Sundaeschna cattienensis
Katatani and Kiyoshi sp. nov. (by present designation)
Other species: Sundaeschna tanintharyiensis
Kiyoshi and Katatani sp. nov.
Etymology. This new genus is named after
Sundaland, a biogeographical region of Southeastern Asia that includes the type locality of thetwo new species.
Diagnosis
Sundaeschna can be distinguished from theother extant genera of the tribe Gomphaeschniniby the combination of following characters: (1) awell-deﬁned T-mark on the frons, (2) a small
spot of brownish pigmentation at the ends of
R4＋5 and MA along the hind margin of each
wing, (3) margin of central depression in 1st
penile segment strongly uplifted, (4) ﬂagella offourth penile segment straight and posteriorly
protruding, (5) dorsum of tenth abdominal segment without tiny denticles, and (6) inwardly
twisted and knife-shaped male cerci.
Description
Male. Large sized dragonﬂies; body blackwith bright green-yellowish markings when
alive.
HEAD: Large and globular. Prementum withmedian cleft. Gena with green spot. Antefrons
gently protruded anteriorly; postfrons depressed

medially and black, laterally invaded by a pair oftransverse green spots originating from green
area of the antefrons, and forming a T-mark. Vertex, antennae, and occiput black. Vertex about
one-third of the width of frons, globularly protruding anteriorly above median ocellus. Compound eyes pale green in living condition, eyeseam rather short, slightly shorter than width ofvertex; diameter of head across eyes less than
twice frons width.
PTEROTHORAX: Black with greenish spots.
Legs short but robust, hind femur slightly shorter
than synthorax.
WINGS: Broad and long, base of hind-wing inmale shallowly excavated, margin of anal ﬁeld
gently angled. Small distinct spot with brownish
pigmentation present at posterior end of R4＋5
and MA in all wings. Anal triangle variable, 1 to
3 celled; anal loop small, 3- to 4-celled. Discoidal cells 2- to 3-celled in every wing; base of discoidal cell shortly distal of level of arc. Supratriangle entire or 2 celled; basal space entire. Single
cubital nervure present in all wings. Discoidal
ﬁeld with two or three rows of cells; IR3 notforked; R3 making an abrupt curve towards thepterostigma. Rspl and Mspl well deﬁned, with asingle row of cells between IR3 and two rows ofcells between MA, respectively. Pterostigma of
medium size, braced; membranule well developed, reaching nearly half of anal triangle.
ABDOMEN: Longer than hind-wing, globular
at base, constricted at middle of 3rd segment,
inﬂated again to middle of 4th segment, then narrowing gradually to the end. Dorsum of 10th segment without tiny denticles. Auricles angulate
with tiny teeth on posterior margin. Laterally,
cerci narrow on basal third, dilated and spatulated on apical two-thirds; dorsally, twisted
inward from base to apex. Ventrally, epiproct
narrow and biﬁd at apex; laterally, gently curved
upward.
PENIS: First segment (sperm vesicle) broadly
hollow ventrally and cup-shaped, marginal ﬂange
greatly uplifted. In ventral view, width of protruding marginal ﬂange of 1st segment not
expanded in upper part. Second segment without

A New Genus and Two New Species of Aeshnidae

dorsal projection. Third segment shorter than 2nd
segment, and as long and wide as 4th segment,with one pair of dorso-lateral clefts. Fourth segment with one pair of apical lobes separated fromeach other dorsally. Flagella straight and protruding posteriorly from apex of 4th segment.
Female. Unknown.
Distribution. Type species, Sundaeschna cattienensis Katatani and Kiyoshi sp. nov., from
Vietnam; S. tanintharyiensis Kiyoshi and
Katatani sp. nov., from Myanmar.
Sundaeschna cattienensis Katatani and Kiyoshi
sp. nov.
(Figs. 1–7)

Etymology. The new species is named after
its type locality, Cat Tien National Park in Dong
Nai Province in Vietnam.
Diagnosis. Sundaeschna cattienensis Katatani
and Kiyoshi sp. nov. differs from the congenericspecies S. tanintharyiensis Kiyoshi and Katatani
sp. nov. as follows: (1) cerci of S. cattienensis
twists inward more strongly than those of S.
tanintharyiensis; (2) the width of the fork at theposterior part of epiproct of S. cattienensis is
wider than that of S. tanintharyiensis.
Male (Holotype)
HEAD (Figs. 1–2): Labium and labrum orange
red; mandibles orange red with yellow-green
spots at base. Anteclypeus and postclypeus
orange red, latter with yellow-green band at posterior border, not extending to lateral margin;
antefrons protruding anteriorly, black with ventral third coarsely wrinkled; postfrons depressed
medially and black, laterally invaded by one pairof transverse green spots originating from green
area of antefrons and forming T-mark. Vertex,
antennae, and occiput black. Vertex about onethird of frons width, globularly protruding anteriorly above median ocellus, with one pair of small
faint green spots at base. Compound eyes palegreen, eye-seam slightly shorter than vertex
width; diameter of head across eyes less than3

twice frons width. Black hairs present on lateralsides of mandible, frons, postclypeus, vertex andocciput.
PTEROTHORAX (Fig. 1): Black with green
spots as follows: dorsal stripes cigar-shaped, notreaching antealar ridge, transversely rectangularbands below antealar ridge extending outwards
towards humeral suture; broad stripe on mesepimeron with ventral end rounded; posterior halfof metinfraepisternum brown; small triangulardorsal spot present on metepisternum; posterior
three-quarters of metepimeron. Legs black, hindfemur markedly shorter than pterothorax(10 : 14).
WINGS (Fig. 7): Hyaline with brownish area
in basal part; veins black; small distinct brownish
spot present on the ends of R4＋5 and MA;
pterostigma, 3.3 mm on forewing, 3.0 mm on
hindwing, dark reddish-brown, braced on allwings and underlaid by 1.5 cells. Venation simple, anal triangles two-celled, supra-triangles
entire; triangles three celled in forewings, twocelled in hindwings; anal loops three celled.
Nodal index 5 : 15 : 15 : 5 in forewings,
7 : 10 : 12 : 6 in hindwings. One cubito-anal crossvein in all wings. IR3 not forked with only one
row of cells between it and Rspl. Two rows ofcells between MA and Mspl in both wings. Discoidal ﬁeld starts with two rows of cells. Anal
angle roundly angulate; membranule well developed and pale brownish, reaching basal half ofanal triangle.
ABDOMEN (Figs. 1, 4–6): Slender, blackwith greenish and yellow-greenish markings. S1and S2 globular, S3 weakly constricted at middle, S4–5 parallel-sided, S6–8 gradually narrowed, distal half of S9 slightly widened, S10slightly widened posteriorly. Dorsally, S1 with
one pair of very tiny yellow spots at middle, S2
with large triangular AD, paired pyriform MD
and paired triangular PD spots; paired triangular
PD spots of S3–5 sub-triangular and closely
adjoining, largest at S3 and gradually becoming
smaller on posterior segments. Laterally, S1 withlarge green spot. S2 with AL spot covering auricle and two PL spots. S3 with one AL spot. S4–9

4

T. Kiyoshi et al.

Figs. 1–7. Sundaeschna cattienensis Katatani and Kiyoshi sp. nov. 1, body, lateral; 2, head; 3, penis, upside
down in lateral view lateral view; 4, cerci, dorsal view; 5, cerci, lateral view; 6, epiproct, ventral view; 7, rightwings.

A New Genus and Two New Species of Aeshnidaewith one yellow AML spot, distinct on S4–7 andobscure on S8–9. S10 black with yellow-green
fringe at antro-ventral margin. Auricle with hindangles triangular, posterior margin furnished withsmall number (17–18) of black acute spines
loosely set. Dorsum of S10 with vestigial longitudinal carina, without tiny denticles. Cerci
5.2 mm in length, approximately 2.6 times aslong as S10; laterally, narrow on basal third, withapical two-thirds dilated and spatulate, and apicalthird moderately curving downward; a small protrusion pointing downward near the base. In dorsal view, outer edge of cerci twisting strongly
inward, tip of inner side sharply pointed.
Epiproct about two-thirds as long as cerci, laterally, smoothly curved upward; apex with stout
teeth protruding upward; in ventral view, basal
two thirds biﬁd with two forks diverging at about
120 degrees, apical notch about twice as broad as
epiproct at base.
PENIS (Fig. 3): First segment broadly hollow
ventrally and cup-shaped, with marginal ﬂange
uplifted. Second segment curved ventrad, withvestigial dorsal projection. Third segment shorter
than 2nd segment and as long and wide as 4th
segment, with a pair of dorso-lateral clefts. Apical lobes of 4th segment separated from eachother dorsally. Flagella straight and protruding
posteriorly, slightly curving outward in ventral
view; in lateral view, the entire length (including
the embedded part) of ﬂagella 1.5 times as longas glans, but exposed length only about one thirdglans length. Ventrobasal plate of 4th segment
ﬂat in lateral view. Ventral surface of ﬂagella notcovered, lacking membranaceous properties ofglans, in ventral view.
Variation in paratype
WINGS: Anal triangles three celled, supra-triangles entire (one cross vein in right hindwing);
triangles three celled in forewings, two or threecelled in hindwings; anal loops three celled;
nodal index 7 : 17 : 15 : 7 in forewings, 7 : 10 :10 : 7 in hindwings. Discoidal ﬁeld start withthree rows of cells.
Measurements (mm). Holotype: ♂ abdomen＋

5

cerci 51.4 mm, hindwing 35.5 mm, with maximum width 11.8 mm. Paratype: ♂ abdomen＋
cerci 51.1 mm, hindwing 36.2 mm
Female: unknown.
Material Examined. Holotype: male, 16-V2010, Cat Tien National Park, Dong Nai Province, southern Vietnam (11.274 N, 107.220 E, ca.
165 m a.s.l.), leg. Kanji Kishi. Holotype wasdeposited in the National Museum of Nature andScience, Tokyo. Paratype: 1 male, data the same
as for the holotype; leg. Native collector. Paratype will be deposited in the Vietnamese
National Museum of Nature.
Notes: Cat Tien national park is located in thesouth of Vietnam, approximately 150 km north of
Ho Chi Mihn City. It has an area of about
720 km2, and protects one of the largest areas oflowland tropical and primary forests left in Vietnam. Two males were collected during the daytime, inside the forest. One of the males was ﬂying in a circular manner within a small gap in theforest. Another male was perched on a twig withthe abdomen hanging vertically, in a manner typical of aeshnids. In addition, another male wasobserved ﬂying above the grasses alongside forest roads, again during the daytime.
Sundaeschna tanintharyiensis
Kiyoshi and Katatani sp. nov.
(Figs. 8–14)

Etymology. The new species is named after
its type locality, the Tanintharyi Region, Myanmar.
Diagnosis. S. tanintharyiensis Kiyoshi and
Katatani sp. nov. differs from the congeneric species Sundaeschna cattienensis Katatani and Kiyoshi sp. nov. as follows: (1) the width of the fork
at the posterior part of epiproct of S. tanintharyiensis is narrower than that of S. cattienensis. (2) inwardly twist of cerci of S. tanintharyiensis weaker than those of S. cattienensis.
Male (Holotype)
HEAD: Labium and mandibles brown; labrum

6

T. Kiyoshi et al.

Figs. 8–14. Sundaeschna tanintharyiensis Kiyoshi and Katatani sp. nov. 8, body, lateral; 9, apical parts ofpenis, upside down in lateral view; 10, apical parts of penis, ventral view; 11, cerci, dorsal view; 12, cerci,lateral view; 13, epiproct, ventral view; 14, right wings.

A New Genus and Two New Species of Aeshnidaebrown with a pair of faint yellowish spots;
anteclypeus and postclypeus brown, the latterwith a narrow yellow greenish band at the posterior border not extending to lateral margin; antefrons black with ventral third coarsely wrinkled,lateral side greenish-yellow; postfrons depressed
medially and black, laterally invaded by a pair oftransverse yellow spots originating from yellow
area of antefrons, and forming a T-mark. Vertex
about one third of the width of frons, globularly
protruded anteriorly above median ocellus, witha pair of small faint green spots at the base.
Compound eyes pale green, eye-seam short, a little shorter than the width of vertex; diameter ofhead across eyes less than twice the width offrons. Black hairs present on lateral sides ofmandible, frons, postclypeus, vertex and occiput.
PTEROTHORAX (Fig. 8): Black with greenish spots. Dorsally, a pair of narrow dorsal stripes
diverging downward from each other, upper ends
separated from a short rectangular stripe extending outwards towards the humeral suture. Stripesof mesepimeron gradually narrowed upward.
Metepisternum with a narrow yellowish stripe
extending from dorsal margin to middle. Posterior three-quarters of metepimeron green. Mesinfraepisternum with a faint greenish spot, posterior half of metinfraepisternum green. Legs
black.
WINGS (Fig. 14): Hyaline and basally ambertinted; veins black; a small distinct brownish spotat the posterior ends of R4＋5 and MA as in S.
cattienensis. Pterostigma dark reddish-brown,
braced in all wings and underlaid by 1.8–2.5
cells. Venation simple, anal triangles and supratriangles entire; triangles three celled in forewings, two celled in hindwings; anal loops threecelled. Nodal index 5 : 15 : 15 : 6 in forewings,
7 : 10 : 10 : 7 in hindwings. One cubito-anal crossvein in all wings; IR3 not forked; only one rowof cells between IR3 and Rspl. Anal angle
roundly angulated; membranule well developed
and pale brownish, reaching basal half of anal
triangle.
ABDOMEN (Figs. 8, 11–13): Black with yellowish markings. S1–2 globose, S3 weakly con-7

stricted at middle, S4–5 parallel-sided; S6–8
gradually narrowed backward, distal half of S9slightly widened, and S10 almost parallel-sided.
Dorsally, S1 with a pair of very tiny yellow spotsat middle, S2 with a large triangular AD, paired
pyriform MD, and paired triangular PD spots;
paired PD spots of S3–5 sub-triangular andclosely adjoining, largest at S3 and gradually
becoming smaller in posterior segments. Laterally, S1 with a large green spot; S2 with an AL
spot covering auricle and two PL spots; S3 withan AL spot; S4–9 with a yellow AML spot, distinct on S4–7 and obscure on S8–9; S10 blackwith yellow green fringe at antero-ventral margin. The hind angles of the auricles triangular,
and the posterior margins are furnished withloosely set and acute black spines. Dorsum of
S10 with vestigial longitudinal carina and without tiny denticles. Cerci about twice as long as
S10, in lateral view narrow basally, with apicalhalf dilated and spatulated and a small ventral
protuberance at basal two-ﬁfths (Fig. 4); in dorsal view, weakly twisted inward. Epiproct about
two-thirds as long as cerci, apex upcurved gently
and deeply notched apically, two forks diverged
from each other at about 90 degrees, depth of theapical notch nearly the half of its width and oneﬁfth as long as epiproct.
PENIS (Figs. 9–10): First segment broadly
hollow ventrally and cup-shaped, with marginal
ﬂange uplifted. Dorsal projection of 2nd segment
very vestigial. Third segment shorter than 2nd
segment and as long and wide as 4th segment,with a pair of dorso-lateral clefts. Apical lobes of
4th segment separated along from each otherdorsally. Flagella robust and straight, protruding
posteriorly and slightly curving outward in ventral view. Ventrobasal bony plate of 4th segment
protruded in lateral view.
Female: unknown.
Measurements (mm). Holotype: ♂ abdomen＋
cerci 43 mm, hindwing 31 mm.
Material Examined. Holotype: male (NSMT-IOd-17675), 7-VI-2016; Tanintharyi Township,
Myeik District, Tanintharyi Region, Myanmar,
12.085 N 99.009 E, 18 m a.s.l., leg. T. Kiyoshi.

T. Kiyoshi et al.

8

Holotype is deposited in the National Museum of
Nature and Science.
Discussion
The tribe Gomphaeschnini comprises ﬁve genera:
Sarasaeschna, Gomphaeschna, Linaeschna, Oligoaeschna and Sundaeschna. A cladistic analysis
by von Ellenrieder (2002) reconstructed reciprocalmonophylyof(Sarasaeschna＋Gomphaeschna)
and(Linaeschna＋
Oligoaeschna). The morphological traits of Sundaeschna were discussed, with comparisonsamong Gomphaeschnini genera.
Regarding the color pattern of the body, Sundaeschna most resembles Sarasaeschna andGomphaeschna, with a well-formed T-mark on
the frons and heliochromic patterns on the abdomen. Sarasaeschna was split from the genus Oligoaeschna, chieﬂy due to the differences in male
penile characters noted by Karube and Yeh(2001). They described Sarasaeschna based onminute comparisons of the penile organs ofGomphaeschnini, with illustrations showing the
apical three segments in lateral view, and thefourth segment in ventral view. With regards tothe penile organ of Sarasaeschna, the width ofthe protruding marginal ﬂange of the ﬁrst segment is expanded in the upper part in ventral
view, and ﬂagella of the fourth segment is welldeveloped and sickle-shaped, as long as theglans, and sometimes twisted. This latter character is shared with Gomphaeschna. The penis of
Oligoaeschna is short and robust. The ﬂagella ofthe fourth segment is slender and bent near apex
(except in O. venatrix and O. uroptera, where it
is not bent). The ﬂagella of Linaeschna is straightand very short in comparison with other genera.
The penis structure of Sundaeschna is simple androbust. In ventral view, the width of the protruding marginal ﬂange of the ﬁrst segment is not
spread in the upper part. The ﬂagella are thickand straight, protruding posteriorly, and slightly
curving outward in ventral view. With regard to
the penile structure, Sundaeschna most resembles to Oligoaeschna.

The wings of Sarasaeschna, Gomphaeschna
and Oligoaeschna are hyaline in males, and are
more or less tinted with amber in females. The
costal region of the forewings of Linaeschna isdarkly pigmented. The wings of all species in thegenus Sundaeschna are hyaline with a small, but
distinct, brownish spot that covers the ends of R4＋5 and the MA along the hind margin. This trait
highlights the differences between this genus andother genera, and hence may be useful in identiﬁcation.
The male cerci of Oligoaescha is expanded
and leaf-like shaped (except in O. venatrix,
where it is extremely long and slenderly stalked).
For Sarasaeschna, Linaeschna, and Gomphaeschna, it is not greatly expanded or leaf-like, but
is usually slender and knife-shaped. Sundaeschna
also has a slender and knife-shaped male cerci,
but it twists strongly inward in the dorsal view.
There was not enough genetic material sampled
to enable a molecular phylogenetic analysis. Thisis because most members of Gomphaeschnini arerare species, and hence records are scarce andscattered. The phylogenetic position of the genus
Sundaeschna within Gomphaeschnini is still
unknown, but it might be in an intermediate position between the clades (Sarasaeschna＋Gomphaeschna) and (Linaeschna＋Oligoaeschna).
Acknowledgements
The authors are grateful to K. Kishi who
accompanied NK on the Vietnam trips, andhelped with the collecting of specimens. This
study was partly carried out by the international
cooperative project “Biological Inventory withspecial attention to Myanmar” as the integrated
research initiated by the National Museum of
Nature and Science, Japan based on MoU
between Forest Department, Ministry of Natural
Resources and Environmental Conservation,
Myanmar, and also in co-operation (based on anMoU) with NMNS and the Vietnam National
Museum of Nature. This research was also partly
supported by JSPS KAKENHI 16K21671 and
16K07515.

A New Genus and Two New Species of Aeshnidae

References
von Ellenrieder, N. 2002. A phylogenetic analysis of theextant Aeshnidae (Odonata: Anisoptera). Systematic
Entomology 27: 437–467.
Karube, H. and W-.C-. Yeh. 2001. Sarasaeschna gen.
nov., with descriptions of female S. minuta (Asahina)
and male penile structure of Linaeschna (Anisoptera:
Aeshnidae). Tombo, 43: 1–8.
Kiyoshi, T., N. Katatani, T. Kompier and W.C. Yeh 2016.
A new species and additional records of the genus
Sarasaeschna from Laos and Vietnam (Odonata,
Anisoptera, Aeshnidae). Bulletin of the National
Museum of Nature and Science, Series A (Zoology) 42:
181–188.

9

Schorr, M. and D. Paulson, 2017. World Odonata List.
Available from: https://www.pugetsound.edu/academics/
academic-resources/slater-museum/biodiversity-resources/
dragonﬂies/world-odonata-list2/ (accessed 1 May 2017.)
Steinmann, H. 1997. World Catalogue of Odonata. Volume II. Anisoptera. Das Tierreich, Teilband 111. 636
pp. Verlag Walter de Gruyter, Berlin, New York.
Tsuda, S. 2000. A distributional list of world Odonata.
430 pp. Published by the author, Osaka.
Walker, E. M. 1912. The North American Dragonﬂies of
the Genus Aeshna. University Toronto Studies (Biological series), 11: 1–213.
Walker, E. M. 1958. The Odonata of Canada and Alaska.
Volume Two. 318 pp. University of Toronto Press,
Toronto.