231: Orthetrum triangulare malaccensis Förster, 1903

        Number: 231 / Family: Libellulidae / Genus: Orthetrum

Species: Orthetrum triangulare malaccensis / Southern Blue-tailed Forest Hawk*

Province(s) sighted: Yala

Habitat: Small pond in forested area

In flight: August / Sightings (by me): Rare

Species easily confused with: Orthetrum t. triangulare

*Name made up by me based on the translation of the two subspecies in Thailand now adding 'Northern' for Orthetrum triangulare triangulare and 'Southern' for O. triangulare malaccensis, based on the latter only being found in the very deep south of Thailand.

Another Orthetrum species -- or rather -- subspecies in this case that I was desperate to see was Orthetrum triangulare malaccensis, and the common name translated from the Thai name as the Southern Blue-tailed Forest Hawk. Orthetrum t. triangulare is a large and common species found pretty much throughout Thailand at slow-moving rivers, streams and trickles in well forested areas. However, as of yet the range isn't known to extend into to the very bottom provinces of Thailand (namely Pattani, Songkhla, Narathiwat and Yala). However, over the past decade more ode hunters have hit the very south -- including myself back in 2018 -- aiming to find new species for the country. Oddly, O. triangulare malaccensis had already been recorded in Yala and I saw it, albeit fleetingly, fly straight past me at a small stream in Narathiwat. This trip in August, 2025 seemed to be going the same way in the fact that none showed for the first 8-9 days and it was becoming a little frustrating. Amazingly, however, on a day searching a new area in Yala, noticed a small pond created by seepage which was surrounded by foliage and tall trees. It was too early to search then as it was morning and Noppadon Makbun and I decided that it would have been better to leave that place until after we had visited the stream we intended to find first. On the way back, we were amazed not only to find 3-4 idividuals of O. triangulare malaccensis, but we also saw a further two new species for my records in Orthetrum schneideri and the incredibly impressive Indaeschna grubaueri, all three of which I was desperate to see but had almost given up the ghost on them. That said, O, t. malaccensis was incredibly skittish and took a good which to photograph and I am happy with the results, though sadly, I didn't get to see the female... until next time!

The Male

Though very similar to the common species, Orthetrum t. triangulare, there are a number of key differences. One being the abdomen is possibly less robust; secondly, the blueish patch is noticeably shorter; and finally, as mentioned, location. It also seems that this subspecies has some greyish-blue pruinescence to the thorax.