Euphaea ochacea and teneral Euphaea decorata

On April 30 we were looking for dragonflies along the QL32 in Yen Bai Province, just west of Nam Bung, when we ran into several good-looking Euphaea specimens. I was able to take some pictures of the first one, but it flew off before I could get close. Thereafter we saw several other Euphaea specimens, but they differed from the first, in that the first had a dark spot central to the hindwing and hyaline tips. The other males all had much more even coloration of the hindwing and diffusely colored wingtips. These were E. ochracea. Remarkably, when studying the photos, the wing shape for the first specimen also appears somewhat different. The ration between the hindwing length and maximum width is 3.52. For the other specimen photographed it is 3.68. Here is a key, because E. decorata in fact has a different wing shape. It has slightly broader wings that show an S-curve towards the tip. Ochracea generally appears more slender-winged, with an gentle even curve towards the tip. This immature specimen is reminiscent of even broader winged E. ornata of Hainan in coloration. All these species are as far as the appendages go very similar. Under the microscope there are minute differences between E. ochracea and E. decorata, and when comparing the a specimen I caught a week later, but similarly colored and at the same location, to an adult E. decorata I could not find differences, although it is different from E. ochracea. Thus, this colorful specimen is in fact E. decorata, occurring side by side, almost, with E. ochracea. Euphaea ochracea is recorded from various provinces in Vietnam and also in the north, but E. ornata is a Hainan endemic, although it has been claimed from for instance Yunnan and Guangdong. Such records may refer to brightly colored and immature E. decorata, as in fact Matti suggested relating to mine, on the first version of this post, in which I originally suggested the specimen with the darker patch in the wing might be E. ornata.

*I received the Campion paper courtesy of Matti Hamalainen and based on his suggestions went back to Yen Bai and studied the concerned species in hand. Many thanks. The issue is now resolved.

Beautiful male Euphaea ochracea

The female of Euphaea ochracea

The fascinating male Euphaea species displaying  coloration of Euphaea ornata, but in fact immature E. decorata