Phytomyza omlandi Scheffer & Lonsdale

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 : 77-78

Phytomyza omlandi Scheffer & Lonsdale

( Fig. 195 )

Material examined. GEORGIA: Clarke Co., Athens , North Oconee River, 22.iii.2013, em . 18.iv–2.v.2013, C.S. Eiseman, ex Gelsemium sempervirens , #CSE303, CNC358482–358485 (3♂ 1♀); NORTH CAROLINA: Scotland Co., Laurinburg , St. Andrews University, 1.xii.2015, em . iv.2016, T.S. Feldman, ex Gelsemium sempervirens , #CSE2441, CNC653956 (1♀).

Host. Gelsemiaceae : Gelsemium sempervirens (L.) W.T. Aiton.

Leaf mine. ( Fig. 195 ) Broadly linear throughout, but often so contorted as to form a secondary blotch. Mines are largely greenish (interparenchymal); minute frass grains are visible in transmitted light.

Puparium. Brown; formed within the mine, with the anterior spiracles projecting through the upper epidermis. The spiracles are surrounded by a small, transparent, circular “window” in the leaf’s upper epidermis where all the green tissue has been consumed.

Distribution. USA: *GA, NC (Scheffer & Lonsdale 2011); we found leaf mines at Highlands Hammock State Park, FL.

Comments. Scheffer & Lonsdale (2011) noted that in two years spent in North Carolina, leaf mines on Gelsemium plants were only observed in natural settings despite the fact that G. sempervirens is often planted as an ornamental. Although our reared specimens were from wild plants, we also collected mines from an ornamental G. sempervirens vine growing on the front stoop of a house in suburban Roswell, Georgia, but only parasitoids emerged. Phytomyza omlandi is so far the only agromyzid reared from Gelsemium , but at two locations in Florida (Greenville and Highlands Hammock State Park) we found probable mines of the polyphagous species Liriomyza schmidti (Aldrich) . They were linear as in P. omlandi , but epidermal rather than interparenchymal, and pupation was external rather than internal. T. Feldman has collected much narrower epidermal mines of an unknown agromyzid from G. sempervirens in North and South Carolina; these mines are not uncommon but so far have always been aborted.

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.