Microgomphus souteri Fraser, a new addition to the Odonata (Insecta) fauna of
Kerala, southern India
K.G. Emiliyamma 1, Muhamed Jafer Palot 2 & C.Radhakrishnan 3
1,2,3 Zoological Survey of India, Western GhatRegional Centre, Jaferkhan Colony, Eranhipalam P.O., Kozhikode, Kerala 673006, India
Email: 1kgemily@gmail.com (corresponding author), 2 palot.zsi@gmail.com,3 radhakrishnan.zsi@gmail.com
Date of publication (online): 26 June 2012
Date of publication (print): 26
June 2012
ISSN 0974-7907 (online) |
0974-7893 (print)
Editor: Albert Orr
Manuscript details:
Ms # o2885
Received 27 July 2011
Final received 11 May 2012
Finally accepted 01 June 2012
Citation: Emiliyamma,
K.G., M.J. Palot & C. Radhakrishnan (2012).Microgomphus souteri Fraser, a new addition to the Odonata(Insecta) fauna of Kerala, southern India. Journal of Threatened Taxa 4(6): 2667–2669.
Copyright: ©
K.G. Emiliyamma, Muhamed Jafer Palot & C. Radhakrishnan 2012. Creative Commons
Attribution 3.0 Unported License. JoTT allows unrestricted use of this article in any medium
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credit to the authors and the source of publication.
Acknowledgements: The authors are grateful to the
Director, Zoological Survey of India, Kolkatafor facilities and encouragement. Thanks are also due to Shri.
K.V. Uthaman, Wildlife Warden, AralamWLS for the permission accorded to conduct the field trip in the conservation
area.
The Odonata fauna of Kerala comprises 138 species, representing
80 genera and 12 families (Emiliyamma & Radhakrishnan 2006; Emiliyamma et
al. 2007). The present report adds
an additional record from Kerala.
During a faunistic survey tour conducted on 6 June 2010 in the Aralam Wildlife Sanctuary (between 11053’1”–11059’14”N
and 75047’29”–75055’58”E), located in the Brahmagiri slopes of the northern Western Ghats in the Kannur District of Kerala, we collected a specimen of Microgomphus souteri Fraser, 1924 at Valayamchal. The specimen was collected at around
0200hr below a tube light. The
weather was rainy and windy all through the day and night and the surroundings
were thoroughly drenched. It is
conjectured that the weather conditions might have prompted the species to come
to the light at night.
The genus Microgomphus belongs to the
family Gomphidae. Its members are among the smallest species in the family,
and are coloured black marked with greenish-yellow. The genus Microgomphus is defined by
the following characters: Discoidal cell of forewing
and hindwing different in shape, that of forewing
shorter than in hindwing; incomplete basal antenodal nervure absent; superior anal appendages with an
inner branch, inferior appendages slightly notched at the tips (Image 1),
further they have more than two transverse nervures between the sectors of the
arc, from arc to bifurcation of Rs (Radial Sector) in
fore and in hindwing.
They are
distributed in the humid parts of the Western Ghats and the northeasternpart of India at an elevation of 609.5m and above. Other species of the genus are distributed in Myanmar,
Malaysia, Sumatra, Singapore, Sri Lanka, Cambodia, Laos, Vietnam, Borneo and
Africa. Species of the genus are
arboreal by nature, but occasionally the males descend and settle on rocks in
midstream; they do not wander far from their parent streams, and may be found
settled on vegetation, usually beside the water. The larvae breed in deep pools in lowland and submontane streams flowing through heavy primary rainforest
(Fraser 1934). The genus Microgomphus is represented
in India by four species: M. chelifer Selys, 1858, M. souteri Fraser, 1924, M. torquatus (Selys, 1854) and M. verticalis (Selys, 1873) (Subramanian 2009). Of these, only M. souteri is endemic to
the Western Ghats (Prasad & Varshney 1995).
The characters
of the specimen collected tally (though with some minor variations) with that
of M. souteri (Fraser
1924). The genus Microgomphus and the
species M. souteri Fraser is reported here for the first time from Kerala. The morphometricdetails of the specimen are given below with their diagnostic characters.
Microgomphus souteri Fraser
(Image 2)
Material
examined: 06.vi.2010, 1 male, AralamWildlife Sanctuary, Kannur District, Kerala, India,
coll. Muhamed Jafer Palot, Registration No. ZSI/WGRC/IR-INV-2240.
Measurements: Total length
- 40mm; Abdomen - 28mm; Forewing - 25mm; Hindwing -
23mm.
Diagnostic
characters: Antehumeral stripes on
thorax not confluent with mesothoracic collar; vertex
without marking; labrum black, marked with two large
triangular greenish spots; abdominal segments 4 and 5 without mid dorsal oval
yellow spots; 8 to 10 without yellow markings.
However, we
have observed minor variations from the description: anterior collar of prothorax black, two large yellow spots on either side; antehumeral stripe broad, short; mesepimeronand metepimeron yellow, separated by a thin black
stripe at the posterolateral suture; undersurface of all coxae and
thorax yellowish with white pruinescence; wings with
pale yellow at the subcostal and cubitalspaces extended up to one cell length; marking on abdominal segments similar,
but apicolateral spot absent on segment 2; markings
on segment 6 bilobed and on 7th segment
not overlapping the transverse suture.
Fraser (1924)
described Microgomphus torquatus souteri based on a
specimen collected from Coorg, Karnataka. According to Fraser (1934), the species
is confined to Coorg and South Kanaraand breeds in Sampaji and HalleryRivers and the Kibribetta stream, 609–1067 m, Coorg. The
present collection locality of the species from Kerala is however, only about
40–50 km south of the type locality of the species. With the present discovery, a total of
139 species of dragonflies and damselflies (Odonata)
representing 81 genera are now known to occur in Kerala. The specimen studied is deposited in
the faunal depository of the Western Ghat Regional
Centre, Zoological Survey of India, Kozhikode, Kerala.
Distribution: India: Kodagu, Dakshina Kannada (Karnataka)
and Kannur (Kerala) - present report.
REFERENCES
Emiliyamma, K.G.
& C. Radhakrishnan (2006). First report
of Cyclogomphus heterostylus Selys (Odonata:Insecta) from Kerala, South India. Records
of Zoological Survey of India 106(Part-2): 123–124.
Emiliyamma, K.G., C.Radhakrishnan & M.J. Palot(2007). Odonata (Insecta) of Kerala. Zoological Survey of India, Kolkata,
243pp.
Fraser,
F.C. (1924). Microgomphus torquatus souteri Fraser, Records of Indian Museum 26: 427, 474.
Fraser,
F.C. (1934). The
Fauna of British India Including Ceylon and Burma. Odonata—Vol. 2. Taylor &
Francis Ltd., London, 398pp.
Prasad, M. & R.K. Varshney(1995). A checklist of the odonata of India including data on larval studies. Oriental Insects 29: 385–428.
Subramanian,
K.A. (2009). A Checklist of Odonata (Insecta) of India: 1–36. http://www.zsi.gov.in/checklist/Odonata/pdf. Downloaded on 20 December 2010.