Phytomyza minuscula Goureau

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 : 77

Phytomyza minuscula Goureau

( Fig. 194 )

Material examined. VERMONT: Lamoille Co., Stowe , Hell Brook, W of Mountain Rd. , 6.ix.2015, em. 23– 26.ix.2015, C.S. Eiseman, ex Thalictrum pubescens , #CSE2072, CNC654547–654559 (8♂ 5♀) ; same collection data, em. 19.iii–23.iv.2016, #CSE2254, CNC654505–654546 (20♂ 22♀).

Hosts. Ranunculaceae : Aquilegia L., Thalictrum fendleri Engelm. ex A. Gray, T. * pubescens Pursh ( Spencer 1981) . Frick (1959) reported rearing this species from cultivated varieties of Aquilegia and Thalictrum as well as from A. formosa Fisch. ex DC., but some of his records may refer to Phytomyza aquilegivora Spencer (Spencer & Steyskal 1986) .

Leaf mine. ( Fig. 194 ) According to Spencer (1981), an “irregular, upper surface linear mine, with frass in conspicuous black strips.” The mines we observed were greenish-white and became quite wide toward the end, with irregular margins. Frass was in discrete grains for the most part, with some short strips toward the end, and as the mines widened the frass grains ceased to form two distinct rows and became irregularly scattered. The larva exits through a slit in the lower epidermis. There are often several mines per leaflet (Ellis 2017).

Puparium. Compact, oval, shining orange, formed outside the mine, “normally adhering lightly to the leaf until dislodged by wind or rain” ( Spencer 1981).

Distribution. USA: CA, *VT, WA; Europe. Frick (1959) additionally recorded this species from CT, DC, ID, IL, and IN, but some of these records may refer to Phytomyza aquilegivora Spencer (Spencer & Steyskal 1986) .

Figures

FIGURES 189–199. leaf mines; 189: Phytomyza hatfieldae spec. nov. in Osmorhiza claytonii; 190: P. hydrophyllivora spec. nov. in Hydrophyllum canadense; 191: P. hydrophyllivora in Hydrophyllum virginianum (yellow puparium at tip of leaf serration, upper right); 192: P. linnaeae (Griffiths) in Linnaea borealis (transmitted light); 193: P. loewii Hendel in Clematis virginiana; 194: P. minuscula Goureau in Thalictrum pubescens; 195: P. omlandi Scheffer & Lonsdale in Gelsemium sempervirens; 196: P. palmeri spec. nov. in Symphoricarpos orbiculatus (transmitted light; puparium at upper left); 197: P. palustris spec. nov. in Micranthes pensylvanica; 198: same, five brown puparia in blisters on lower leaf surface (whitish object along left side of midrib is a coniopterygid cocoon); 199: P. penstemonis Spencer in Penstemon digitalis.