24/05/2014

Rhinocypha orea Hämäläinen & Karube, 2001



Two males engage in (prolonged) agonistic flight, 
Tây Thiên - Tam Dao, on May 24, 2014

Rhinocypha orea was described in 2011 by Hämäläinen & Karube, based upon specimens collected at Tam Dao in the 1990's - but without any precise locality indication.



In 2004 and 2005, a large population with more than 50 individuals was observed at a short section of a stream (downstream of Silver waterfall, Thác Bạc, the major touristic attraction at Tam Dao, at ca 900m asl), but one year later, at the same site, only one specimen was found. At this time Rhinocypha orea was only known from this  stream. The portion of forest concerned is partly surrounded by "su su" fields (known in English as christophine or chayote). Those crops are gaining ground year after year (in conjunction with tourism development) and already adjoining the right bank. Vegetation is cleared, changing canopy shading. Located downstream of the Tam Dao Hill Station, the site is also subject to important pollution discharge, especially at the peak tourist season. The stream banks littered with plastic wastes are a very sad and deplorable sight, especially in a so-called "National Park".


After 2006, Rhinocypha orea just disappeared off from local odonatologists radar screens,  despite regular surveys in the area. Some even came to think that it had vanished, victim of changes in water quality and vegetation. But in mid-May 2014, we received a great news from Tom Kompier who found 2 males : one individual not far from the original site (at ca 900m asl) and the other one at only 300m asl, in the area called Tây Thiên – a touristic complex  structured around "spiritual tourism" with many temples, pagodas and monasteries.


Very excited, I quickly arranged a field trip to Tây Thiên to try my luck at finding this rarety! The first individual was seen at noon just in front of the nunnery. Upstream, I spotted 4-5 other males, and the same number 100 meters downstream of the nunnery. So a total of ca 10 males, at a 300 meters section of a heavily forested stream, with big boulders. All the individuals were seen perched on vegetation and rocks along the stream. Almost all were detected in flight – the vibrant golden-colored wings attract the eye,  that is the least one can say.



This little population inhabit a rather well preserved stream, I wrote “rather” because there are some permanent human activities in link with the nunnery. I don’t know which impact on the water quality  this small religious community may have. I noticed that the (Buddhist) nuns burn all kind of waste at the stream banks (even plastics) and wastewater is discharged directly into the stream. But they do not cut down trees, that’s a very good point - and they even blamed me to catch odonates! Upstream of the nunnery, human activity is almost nonexistent.

male, with flash
Very dark damselfly, but with a surprise well hidden!

in natural light

Forewings hyaline; hindwings with 2 different pattern : oustide black with green sheen at tip, inside (the "surprise") golden and reddish (dark reddish at tip)

Photo in natural light, like all the other images in flight presented here

Rhinocypha orea is only known from Tam Dao National Park in northern Vietnam. It is currently classed as Endangered by the IUCN, on account of its limited range and the paucity of records.

1 commentaire:

  1. Perfect photos of flying of this species, I still remember my feeling as saw them 10 years ago in Tam Dao. Thank you so much for the vision story of the species in nature.

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