Phytomyza thalictrivora Spencer

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 : 86-87

Phytomyza thalictrivora Spencer

( Fig. 210 )

Material examined. MASSACHUSETTS: Berkshire Co., Savoy , 1.vi.2013, em. 11.iii.2014, C.S. Eiseman, ex Thalictrum pubescens , #CSE1000, CNC384793 (1♀) .

Hosts. Ranunculaceae : Thalictrum * pubescens Pursh , T. venulosum Trel.

Leaf mine. ( Fig. 210 ) Upper surface, greenish-white; probably entirely linear, but contorted to form an irregular secondary blotch. Frass is in scattered grains and irregular particles. The larva exits through a slit in the lower epidermis.

Puparium. Oval, orange-brown; at the time of collection it was attached to the underside of a leaflet adjacent to the mined one.

Distribution. USA: FL?, *MA; Canada: AB.

Comments. While known here from a single female, a number of characters allow for it to be identified as Phytomyza thalictrivora , including a relatively large first flagellomere, a broad, subshining orbital plate, characteristically gracile fronto-orbitals and only two rows of acrostichal setulae. This species was only previously known from the Albertan holotype [deposited in CNC and examined here] and a single tentatively identified female from northern Florida ( Spencer & Stegmaier 1973). The type was collected from leaf mines on June 10, and the two adults (both males) emerged 15 days later ( Spencer 1969). Our specimen was collected as a puparium on June 1 and the adult did not emerge until the following year. Occasional females exhibiting a long pupal diapause have also been observed in Aulagromyza orbitalis (Melander) ( Spencer 1969) and (perhaps) Agromyza idaeiana Hardy (this paper; see Agromyza sp. 6).

Figures

FIGURES 208–216. leaf mines; 208: Phytomyza syngenesiae (Hardy) in Tanacetum parthenium; 209: P. tarnwoodensis spec. nov. in Diervilla lonicera; 210: P. thalictrivora Spencer in Thalictrum pubescens; 211: P. tigris spec. nov. in Tiarella cordifolia; 212: P. triangularidis spec. nov. in Senecio triangularis; 213: same; 214: P. vancouveriella spec. nov. in Ƒancouveria hexandra; 215: P. verbenae spec. nov. in Ƒerbena lasiostachys; 216: P. ziziae spec. nov. in Zizia aurea (dark brown puparium on leaf surface, near margin).