Tephritis arizonensis Quisenberry is bivoltine and monophagous, or nearly so, on Baccharis sarothroides Gray (Asteraceae). The F1 larvae feed and develop in non-galled, branch-tip mines, the only Nearctic Tephritidae known to do so; whereas, the F2 larvae develop singly in male or female flower heads. (p. 215)

The lengths of 177 branch-tip mines measured from base to branch apex was 6.6 +- 0.1 (range 3-8.8) mm. The widest width was 1.3 +- 0.1 (Range, 1.0-1.8; n=138) mm at the base of the mine. Mines were scattered over the crowns of host plants. (p. 216)

[T. arizonensis has been reared from B. sarothroides in Tucson, AZ, and Otay, CA. These rearing records come from terminal galls, stem tip mines, and flower heads. Swelling from stem-feeding larvae only occurred during pupation.]