Last Updated on Thursday, 21 September, 2023 11:44:13 AM


INDEX  >  Dragonflies of Borneo  >  Family Libellulidae  >  Genus Orthetrum  >  Orthetrum chrysis (Selys, 1891)


Family Libellulidae
Orthetrum chrysis (Selys, 1891)

Found in Asia: China, Guandong, Hong Kong, Hainan, India, Sri Lanka, Myanmar, Malaysia, Philippines, Peninsular Malaysia, Singapore, Thailand

Identification Guide to ♂♀Orthetrum chrysis

Identification Guide to Male and Female Orthetrum chrysis
common in marshes and clear streams of Borneo

MALE
♂48mm
Body length = 48mm
Wing span = 77mm
Hind wing = 37mm

FEMALE
42mm♀
Body length = 42mm
Wing span = 72mm
Hind wing = 35mm

yellowish egg-mass

S1
Ref: Page 98 of DRAGONFLIES OF PENINSULAR MALAYSIA AND SINGAPORE by A.G. Orr
 



 

Egg mass of a female dragonfly Orthetrum chrysis
Egg mass of a female dragonfly Orthetrum chrysis
♀42mm

More on EGGS OF DRAGONFLIES


O. pruinosum O. chrysis O. testaceum Rhodothemis rufa

♀41mm
2016-09-16 MINI HYDRO

♀42mm
2016-03-19 SG IMAM

♀46mm
2007-10-21 DRAGONFLY POND

♀45mm
2017-06-09 WHITE BRIDGE POND
       

The 4 easily confused Male Red Dragonflies of Borneo

O. pruinosum O. chrysis O. testaceum Rhodothemis rufa
Orthetrum pruinosum Orthetrum chrysis Orthetrum testaceum Rhodothemis rufa

The Genus Orthetrum is distinguished by :
1) Complete antenodal cross vein
2) Discoidal field in the forewing has  3 cell rows through out.

A Rhodothemis rufa is distinguished by :
1) Incomplete antenodal cross vein
2) Discoidal field in the forewing has both 2 cell rows and 3 cell rows.
 




Eyes meet partially along a seam (arrowed)


Eyes barely touch at a centre point (arrowed)

 


MALE
FEMALE
Orthetrum chrysis  MALE
Orthetrum chrysis

2016-03-19 SAT 16:22 SG IMAM

Orthetrum chrysis FEMALE
Orthetrum chrysis

2016-03-19 SAT 15:07 SG IMAM

Ventral View of  a male Orthetrum chrysis
Ventral View of  a male Orthetrum chrysis
Ventral View of a female Orthetrum chrysis
Ventral View of a female Orthetrum chrysis
Face of a male Orthetrum chrysis
Face of a male Orthetrum chrysis
Face of a female Orthetrum chrysis
Face of a female Orthetrum chrysis
Wing venation of a male Orthetrum chrysis
Wing venation of a male Orthetrum chrysis
Wing venation of a female Orthetrum chrysis
Wing venation of a female Orthetrum chrysis
Segment 8, 9 and 10 of a male dragonfly

Upper appendages (One pair)
Lower appendage (Single)
Testes (sperm production organ located on the underside of abdominal segment 9)

Segment 8, 9 and 10 of a male dragonfly

Cerci (singular cercus) are paired appendages on the rear-most segments of many Arthropoda, including insects and Symphyla.

Anisoptera males only have upper appendages, plus one single small knob that is also called lower appendage.
Female odonates only have very small appendages, which are functionless. These are called cerci. See image at right

But Zygoptera males have two pairs of anal appendages: the upper appendages (appendices superiors) and the lower appendages (appendices inferiors).
 

Segment 8, 9 and 10 of a female dragonfly

Appendages (Cerci)
Eggs

For the female dragonflies , genitalia are located underneath the abdomen between segment 8 and 9.

Zygoptera and some Anisoptera (Aeshnidae and Cordulegaster) have an ovipositor, surrounded by valvae. An ovipositor is used to stick eggs in plants, wood or mud. These species are called endofytic.

This Orthetrum chrysis is not a Zygoptera, thus does not have an ovipositor.

Species that donít have an ovipositor (exofytic) simply drop their eggs into the water.







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Ovipositor (Vulvar Lamina)
of Female Dragonflies and Damselflies

Female dragonflies have either one of the two method of depositing eggs from the abdomen:
1- using Ovipositor Structure
2- using Vulvar Lamina

Male do not have an ovipositor. Instead male dragonfly and damselfly have appendages.



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