Brown Hairstreak

About the Brown Hairstreak

The brown hairstreak (Thecla betulae) is a butterfly in the family Lycaenidae. The range includes most of the Palaearctic. The following description of this butterfly was written by Adalbert Seitz in 1909: Z. betulae L. Black-brown; male with a pale diffuse patch, female with a broad orange band beyond the crossveins. Underside ochreous, with dark-edged white lines. In North and Central Europe und Northern Asia eastward to the Pacific. Tutt name males without the pale diffuse patch beyond the crossveins ab. unicolor, while this patch is nearly white in ab. pallida Tutt. In ab. spinosae Gerh. there appear beyond the apex of the cell small orange-spots, which may be paler yellow than the discal spots of the female. The orange discal band of the female is sometimes narrow: ab. restricta Tutt, and sometimes broad (= ab. lata).

females in which the band is pale ochreous instead of orange are ab. fisoni Wheeler, while the band is separated into several spots by the heavily black veins in ab. lineata Tutt. A very remarkable form is ab. cuneata Tutt, which bears a broad orange submarginal band on the hindwing. On the underside the white lines are sometimes more or less... Wikipedia →