Coeliccia didyma

Scientific name: Coeliccia didyma (Selys, 1863)

Family: Platycnemididae

Thai name: แมลงปอเข็มท้องยาวฟ้าสองขีด

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In West Thailand, Coeliccia didyma is commonly found around the waterfall. This species is similar to Chinese C. cyanomelas but differs in markings on the front of synthorax and abdominal segment 9-10, and anal appendges.

male

Young male is black with yellow and changes to blue as it ages. The marking on the front of pterothorax shown in the picture (see upper picture below) and seperate to two pairs of dots, two large ones and two small ones, when it matured (see lower picture below).

female

Female is black with yellow or blue stripes. The marking on S8-9 is white or yellow.

male is pretending to be dead

Recently, I observe the death-feigning, or formally thanatosis, in this species. I collected and released it on the leaf, male C. didyma pretended to be dead for 10 seconds! I've also been observed such behavior in Protosticta curiosa and P. grandis. But when I cought and released the same male again, he suddenly flew away. More intensive study is needed to confirm whether this behavior exist or not.