Coeliccia onoi Asahina,1997

A pair in tandem (Tam Dao, 850m a.s.l)

I must confess that I was not keen on writing this post, because the taxonomic status of C. onoi Asahina, 1997 (described from Tam Dao, northern Vietnam) remains unclear. Indeed, C. onoi resembles closely to Coeliccia cyanomelas Ris, 1912, and according to R.A. Dow, C. onoi is “almost certainly” a junior synonym of C. cyanomelas.

In his description, Asahina did not mention the similarity between those 2 species. It is surprising, because onoi and cyanomelas resemble each other very closely (at least “superficially”, i.e. color pattern and markings) and are likely to share the same habitat (cyanomelas is common in southern China and probably don’t stop at the Vietnamese border…).

The original description and illustrations of Asahina are inadequate, and the type series of C. onoi must be re-examined, consider R.A. Dow.

Until the experts clarify this taxonomic issue (especially by examination and comparison of caudal appendages and penile organ), I decided to keep the name Coeliccia onoi Asahina, 1997 for all the specimens I spotted and photographed around Hanoi (Ba Vi, Cuc Phuong and Tam Dao).

Male (Tam Dao, 850m a.s.l.)

The male is a black an blue damselfly, with striking blue distal abdominal segments. The mesepisternum (dorsum of synthorax) bears a lower pair of short blue stripe, close to the dorsal carina. I spotted also many specimens with a second pair of very small markings on the upper mesepisternum, often reduced to minute blue points. In the Asahina’s description, the holotype male of onoi has only the lower pair of stripes; the upper part of the mesepisternum is entirely black.

In the photos of cyanomelas available on the internet (from China), this upper pair of markings is much more conspicuous than that of “my” specimens.

Male (Hoa Binh Province, 400m a.s.l.)

Sides of synthorax marked with 2 broad blue stripes, the upper one with a square-shaped notch anteriorly.
Abdomen black dorsally; S8 (distal half), S9, S10 and caudal appendages blue dorsally.  Superiors with a ventral subapical tooth at about c.2/3 of their length as well a sharpe spine subbasally ; inferiors have a downward apex.

Lateral view

Dorsal view

A male with 2 pairs of markings on the dorsum of the synthorax, the upper one very small (foothills of Tam Dao)

 Some immature males spotted in June 2013 at Tam Dao :

This species, if distinct from C. cyanomelas, is known from Tam Dao and some other sites of northern Vietnam (rather common sight at Tam Dao, Ba Vi, Cuc Phuong at least), in lowland and mountain forests.

If it is a synonym of C. cyanomelas, then this species is also widespread in China and common over parts of its range at least, with records from Fujian, Guangdong, Guangxi, Guizhou, Hainan, Hong Kong, Sichuan and Zhejiang Provinces, and from Taiwan.

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