Refers specifically to insect wings, as opposed to 羽 which covers bird wings and feathers. Used in entomological contexts and everyday descriptions of bugs.
See also: 羽根 (はね)
The butterfly's wings are very beautiful.
この虫の翅は透明で、光を通す。
This insect's wings are transparent and let light through.
Blattella nipponica (species of cockroach)
German cockroach
The kanji 翅 is composed of 羽 (wing) and 支 (branch, support), suggesting a wing structure. The reading はね is the same as 羽, reflecting the shared native Japanese word for wing.