New state and host records for Agromyzidae (Diptera) in the United States, with the description of thirty new species Author Eiseman, Charles S. Author Lonsdale, Owen text Zootaxa 2018 2018-09-14 4479 1 1 156 journal article 29197 10.11646/zootaxa.4479.1.1 73cc6f7d-b3ec-40c5-adc7-52b9e0cbf236 1175-5326 1452913 93C84828-6EEF-4758-BEA1-97EEEF115245 Agromyza ambrosivora Spencer ( Fig. 64 ) Material examined. COLORADO : Chaffee Co. , Poncha Springs , South Arkansas River , 8.vii.2015 , em . 28.vii– 1.viii.2015 , C.S. Eiseman, ex Helianthus annuus , #CSE1872, CNC654328–654332 (1♂ 4♀); MASSACHUSETTS : Worcester Co. , Sturbridge , Leadmine Rd. , 6.vii.2013 , em . 20.vii.2013 , C.S. Eiseman , ex Ambrosia artemisiifolia , #CSE725, CNC392679 , CNC392680 ( 2♀ ); PENNSYLVANIA : Chester Co. , Pottstown , Warwick County Park , 10.viii.2014 , em . 2.ix.2014 , N. D. Charney, ex Ambrosia trifida , #CSE1371, CNC384846 (1♂). Hosts. Asteraceae : Ambrosia artemisiifolia L., A. * trifida L., * Helianthus annuus L. Some specimens from Los Angeles and Ventura Counties, California, were caught at sites where Artemisia douglasiana Besser was one of the dominant plants, and Spencer (1981) stated that it therefore seems probable that this was the host. He noted that Ambrosia is not known in these counties, but the genus is now known from both counties and several Helianthus species are also present (USDA, NRCS 2017). Leaf mine. ( Fig. 64 ) On Ambrosia artemisiifolia , “several larvae frequently feeding together to form a blackish leaf-mine, which extends from the apex of the pinnately divided leaves towards the midrib” ( Spencer 1969 ). In our example the apices of three lobes were disfigured by the mine. The mine on A . trifida was a brown blotch in the angle between the midrib and a lateral vein; there was a narrow initial linear portion that had been mostly obliterated. The mines on Helianthus ( Fig. 64 ) began near the leaf margin in the basal half of the leaf blade and followed the margin apically, widening gradually. Puparium. Brown; formed outside the mine. Distribution. USA : CA, *CO, *MA, MD ( Scheffer et al . 2007 ), NY ( Scheffer & Lonsdale 2018 ), *PA; Canada : ON.