Placochilus seladonicus is a species of insect in the family Miridae, the plant bugs.

[2] It can be found on dry meadows, roadsides,[3] as well as on areas with tall grassy vegetation[4] or where the preferred host plants live.

[3] Placochilus seladonicus can reach a length of about 5 millimetres (0.20 in).

These small mirids show a dull, whitish blue or gray green body and big eyes.

[3] Nymphs and adults feed on leaves and stems of various plants, especially on flower heads or flower buds[4] of field scabious (Knautia arvensis)[3] that match the color of adult insects.