Tirsa is a genus of moths of the family Crambidae, containing only one species Tirsa fiona. It is found in French Polynesia (Rapa Iti).
| Tirsa | |
|---|---|
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Class: | Insecta |
| Order: | Lepidoptera |
| Family: | Crambidae |
| Subfamily: | Pyraustinae |
| Genus: | Tirsa J. F. G. Clarke, 1971[1] |
| Species: | T. fiona |
| Binomial name | |
| Tirsa fiona J. F. G. Clarke, 1971 | |
The wingspan is 24–28 mm. It is a dark brown moth with dark camouflaging speckles throughout its body. It is also known for its long, narrow antennae, which often extend back over its head, rather than ahead.