Calycomyza michiganensis Steyskal

Eiseman, Charles S. & Lonsdale, Owen, 2018, New state and host records for Agromyzidae (Diptera) in the United States, with the description of thirty new species, Zootaxa 4479 (1), pp. 1-156 : 33-34

Calycomyza michiganensis Steyskal

( Fig. 115 )

Material examined. MASSACHUSETTS: Franklin Co., Northfield , 276 Old Wendell Rd. , 24.iii.2016, em . 24.iv.2016, J. A. Blyth, ex Hieracium praealtum , #CSE2420, CNC654070 (1♂) .

Tentatively identified material. NEW YORK: Dutchess Co., Pine Plains , 79 McNeill Rd. , 22.vi.2013, em . 6.vii.2013, C.S. Eiseman, ex Hieracium , #CSE656, CNC392633 (1♀).

Host. * Asteraceae : Hieracium praealtum Vill. ex Gochnat.

Leaf mine. ( Fig. 115 ) Whitish; beginning as a linear mine on the upper leaf surface, expanding to a full-depth blotch that overruns the linear portion. (Tentatively identified mines formed in June on more mature leaves are confined to the upper leaf surface throughout.) Through the linear portion is a broad, diffuse, brown band containing irregular, blackish frass particles; these particles are sparsely scattered in the blotch.

Puparium. Yellowish-brown; formed outside the mine. The tentatively identified female pupariated within the mine.

Distribution. USA: *MA, MI. We have found a similar leaf mine in ME, in addition to those in NY from which the female was reared.

Comments. This is the first record of any Nearctic agromyzid from Hieracium ; so far we have only found leaf mines on introduced European species. The leaf mines discovered on 24 March were more than two months earlier than we have found larvae of any other Calycomyza in New England. The last larva from this collection exited its mine on 5 April.

The species Calycomyza menthae , C. michiganensis and C. novascotiensis Spencer are nearly indistinguishable, and will appear at similar points in Spencer’s Nearctic keys, depending on the specimen being examined. To differentiate these, the phallus must be examined; the paraphallus is distinct and rodlike in C. menthae (not faded apically as in the other two); in profile, the distiphallus is entirely dark and less than half the length of the mesophallus in C. michiganensis , while it is with a medial fossa and about half the length of the mesophallus in C. novascotiensis .

Figures

FIGURES 109–117. leaf mines; 109: Calycomyza humeralis (von Roser) in Erigeron canadensis (transmitted light, puparium at left); 110: C. humeralis in Erigeron sp. (reflected light, puparium at lower right); 111: C. malvae (Burgess) in Malva sp. (reflected light); 112: C. malvae in Senna marilandica (transmitted light); 113: C. malvae in Sida rhombifolia (reflected light); 114: C. menthae Spencer in Monarda didyma; 115: C. michiganensis Steyskal in Hieracium praealtum; 116: C. platyptera (Thomson) in Helianthus annuus; 117: C. promissa (Frick) in Symphyotrichum ascendens.