Agriocnemis pygmaea (Rambur, 1842) 橙尾細蟌

Agriocnemis pygmaea (Rambur, 1842) 橙尾細蟌
- the world smallest damselfly -

Found in Asia: Bangladesh, China, Guandong, Guangxi, Hong Kong, Hainan, Indonesia, India, Japan, Sri Lanka, Myanmar, Malaysia, Philippines, Peninsular Malaysia, Thailand, Taiwan

The damselfly of Family Coenagrionidae is the most abundant damselfly in Sabah, Malaysia. They are black pattern with ground colour in either green, blue, yellow, orange, or purple.
Some species are two female colour forms, one of which is similar to the male. Their wings are narrow, usually colourless and clear.

They prefer to lay eggs in pond or slow running water. They rest with the body horizontal and the wings pressed together above the abdomen.

Ovipositor of a female damselfly Agriocnemis pygmaea
♀25mm
2017-05-23 SRI INDAH
1- A paired Valves with stylus
2- A cutting Basal blades
A pair of Cerci (Anal appendage)

A female Ariocnemis pygmaea (Rambur, 1842) mating at 5:18PM – an unusual time when other dragonflies and damselflies are stopping activities.

A female with this common color is otherwise difficult to identify without this male Ariocnemis pygmaea mate together.

The male clasped female at the prothorax (neck), a part between the head and the thorex.

Another female Ariocnemis pygmaea at the same drain of previous picture

Female Ariocnemis pygmaea is a confusing species because of color changes with maturity. It could be easily mistaken as Ariocnemis femina if not the male as a pair for identity.

The male curves his abdomen to clasp her prothorax with his anal appendages to form the tandem pair. The male does this clasp less than a second.
The tandem position remained for about 10 minutes during which they flew together from one grass to another hen disturbed.
This heart shape wheel is known as Wheel Position. (In dragonfly the tandem is holding the back of head.)

All males have their genital opening for sperm at the ninth abdominal segment. Beside the first genitalia male Damselflies have a secondary genitalia on the second abdominal.

Before copulation, sperm is moved from the first genitalia (Section 9) into the secondary genitalia (section 2). This is done by The bending the abdomen forward for the first genitalia to touches the secondary genitalia. This take few seconds.
When the sperm in the male secondary genitalia is ready, the pair forming a tandem by male holding by female's neck (prothorax). The female bend up her abdomen to the of the male's genitalia and form the wheel position. The female's abdomen contact with male's secondary genitalia to receive sperm.

The male curves his abdomen to clasp her prothorax.
Noteice that for damselflies the clasping is on the prothorex. But for dragonflies the clasping is on the back of the head

Pair 1	Pair 2	Pair 3

This 1st Female Agriocnemis pygmaea is GRAY form. An unusual color. Normally this female species are RED or GREEN	This 2nd Female Agriocnemis pygmaea is RED form.	This 3rd Female Female Agriocnemis pygmaea is GREEN form. The thorax is pale green in colour with black pattern. Abdomen is pale green with black with the red tail light.

This smallest damselflies in Malaysia is also the smallest in the world . Hind wing is 11 mm. Abdomen Length is 20mm
The male damselfly's head and thorax is pale green in colour with black pattern. Abdomen is pale red with black with the red tail light.
They are not easy to find for they are very small in size. They usually hide low and near the water edge, among thick grasses. They fly slow and float like a moth from one grass to another less than a foot away. But during mating, they are relatively easy to photograph because they seem too weak to fly when the two are in the wheel.

These two families of Agriocnemis pygmaea and Agriocnemis femina oryzae always live in the same territories. Because they mingle so close to each other very often the young male of both are mistaken as the other.

A female Agriocnemis pygmaea 橙尾細蟌 eating a tinny green fly.

Damselflies are beneficial predators because they consume large quantities of insects such as flies, mosquitoes and moths and some eat beetles and caterpillars.

The 3 color developing stages of an Female Agriocnemis pygmaea
		Full Adult Form
Teneral Form	Sub Adult Form	Red Form	Green Form