| Phytobia | |
|---|---|
|   | |
| Phytobia lateralis | |
|  Scientific classification   | |
| Domain: | Eukaryota | 
| Kingdom: | Animalia | 
| Phylum: | Arthropoda | 
| Class: | Insecta | 
| Order: | Diptera | 
| Family: | Agromyzidae | 
| Subfamily: | Phytomyzinae | 
| Genus: |  Phytobia  Lioy, 1864 [1]  | 
| Type species | |
|  Agromyza errans  | |
| Synonyms | |
Phytobia is a genus of flies in the family Agromyzidae, [5] with a worldwide distribution principally in Europe and the Americas. [5]
All known larvae of Phytobia feed on the young xylem within stems of woody plants, creating concealed galleries that may reach considerable lengths (reportedly up to 17 m in P. betulae). [6] [7] P. betulae lays its eggs on the bark of new-growth twigs of suitable birch trees and, after hatching, larvae tunnel downwards along the shoot within the differentiating xylem layer, sometimes reaching the base of the tree. Adults are small- to medium-sized flies (approximately 5 mm in the case of P. betulae). [6] Confirmed host plant families for Phytobia species include Betulaceae, Fagaceae, Rosaceae, Salicaceae, Sapindaceae, and Cupressaceae in North America, Europe, and Australia, with Asteraceae also hypothesized to be a host family based on the finding of possible larval sign on the shrub Wedelia calycina in Guadeloupe. [6] [7] Larval tunnels mar the appearance of certain woods used commercially, and thus may be of economic importance. [7]