Today, August 9, I went to Van Long with the objective of solving the Paracercion puzzle left from last year. I caught two females and took pictures of the prothorax, to show the posterior edge. It has the same indentation as P. melanotum, but I suspect P. malayanum shares this character, so it is not of much help. The lack of marking along the humeral suture, so obvious in P. melanotum, and the shape of the postocular spots is also remarkable, where it not that between these two specimens the size range is extreme, with one specimen having very large spots, but the other much smaller spots, well within the range of P. melanotum. I am still at a loss as to what these are. The pattern of the thorax and prothorax is very similar to that of P. malayanum from Thailand (see Dennis Farrell's blog), but the males seem not significantly different from P. melanotum. I still consider it possible that this population bridges the two "species".
|The first female, with distinctive "melanotum"-like indentation in posterior edge. Markings of prothorax similar to P. malayanum, which may also have similar posterior edge? I do not know.|
|The second specimen, similar in all respects, but with larger postocular spots|
|Habitus of two females, one more blueish, the other yellowish and with considerably larger postocular spots. Both lack the double line on the humeral suture you would expect in P. melanotum|