| Regulus bulgaricus | |
|---|---|
Scientific classification 
| |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Aves |
| Order: | Passeriformes |
| Family: | Regulidae |
| Genus: | Regulus |
| Species: | †R. bulgaricus
|
| Binomial name | |
| †Regulus bulgaricus Boev, 1999
| |
Regulus bulgaricus is a fossil passerine from the Middle Villafranchian (upper Pliocene to lower Pleistocene ) of Bulgaria. This bird is a member of the kinglet family and genus, and is the only fossil kinglet found so far. It is known from a single ulna, which is 13.3 mm long.[1] The fossil was discovered in 1991 near Varshets, Bulgaria, and described by Zlatozar Boev.