Calycomyza cynoglossi (Frick)

(Figs. 163, 342–346)

Material examined. ARKANSAS: Stone Co., Northwest Twp., 36.015277, −92.228669, 30.iv.2022, em. 18.v.2022, C.S. Eiseman & J.A. Blyth, ex Andersonglossum virginianum, # CSE7429, CNC5173501 (1♀); ILLINOIS: Cook Co., Glencoe, Chicago Botanic Gardens, McDonald Woods, 42.149072, −87.789442, 7.vi.2018, em. by 27.vi.2018, J.F. Steffen, ex Lithospermum latifolium, CNC 1135576–1135579 (3♂ 1♀); Kankakee Co., Pembroke Twp., Iroquois County State Wildlife Area, 29.vi.2019, em. 21.vii.2019, C.S. Eiseman & J.A. Blyth, ex Hackelia virginiana, # CSE5709, CNC1990570 (1♀); Mason Co., Forest City, Sand Ridge State Forest, 28.vi.2019, em. 14–15.vii.2019, C.S. Eiseman & J.A. Blyth, ex Hackelia virginiana, # CSE5589, CNC1643633, CNC1643634 (1♂ 1♀); ONTARIO: York Region, Richmond Hill, Glenarden Crescent, 43.865278, −79.410558, 18.vii.2017, em. 1.viii.2017, S. Luk, ex Myosotis laxa, CNC 1766792 (1♂).

Photographed mines. IOWA: Winneshiek Co., Plymouth Rock, 2.vi.2013, MJ Hatfield, occupied mines on Hackelia (BG869604); MICHIGAN: Oakland Co., 42.573244, −83.376928, 12.vii.2020,occupied mines on Hackelia virginiana (iNat 52864122); MINNESOTA: Hennepin Co., Minneapolis, 44.939823, −93.211963, 19.vii.2017, botanicalwanderer, mines on Onosmodium molle (iNat 7119881); NEBRASKA: Douglas Co., Omaha, 41.31317, −96.127979, 10.vii.2022, dvdkssrw, mines on Hackelia virginiana (iNat 125694280); NORTH DAKOTA: Grand Forks, 47.918042, −97.023894, 14.viii.2021, N. Kelso, mines on? Hackelia (iNat 91150971); PENNSYLVANIA: Centre Co., 40.790257, −77.751625, 13.vi.2017, M. Skvarla, occupied mine on? Hackelia (iNat 6633159); 40.835981, −77.848627, 30.viii.2023, D. McClosky, empty mine on Lithospermum parviflorum (iNat 181285523); TEXAS: Travis Co., Austin, 30.382316, −97.768936, 13.iii.2023, J. Bailey, mines on Lithospermum helleri (iNat 162950484); VIRGINIA: Loudoun Co., 39.070308, −77.462892, 14.vii.2023, aljnrn, mine on Hackelia virginiana (iNat 172912644); WISCONSIN: Dane Co., 21.ix.2022, T, Klein, empty mine on Lithospermum onosmodium (BG 2179602); Cross Plains, 18.vi.2011, Ilona L., occupied mine on Hackelia virginiana (BG 531586); ONTARIO: Manitoulin District., 45.915327, −82.4549, 18.viii.2022, R. Jakubowski, mine on Lithospermum officinale (iNat 137801664). ·

Hosts. Boraginaceae: Andersonglossum virginianum (L.) J.I.Cohen (Frick 1959), * Hackelia virginiana (L.) I.M.Johnst., [Lithospermum caroliniense (J.F.Gmel.) MacMill., L. helleri (Small) J.I.Cohen], * L. latifolium Michx., [L. molle (Michx.) Muhl., L. officinale L., L. parviflorum Weakley, Witsell & D.Estes], * Myosotis laxa Lehm. Frick (1956) reported the host as “ Cynoglossum ”; Frick (1959) listed both “ Cynoglossum spp. ” and “ Cynoglossum virginianum ” (the latter now placed in Andersonglossum) as hosts for this fly, but there is no specific record from Cynoglossum L. s. str. (i.e., C. officinale L.), so this host genus requires confirmation.

Leaf mine. (Fig. 163) A whitish linear-blotch on the upper leaf surface. The mine begins with a long, narrow serpentine portion with frass in beaded strips or closely spaced grains along the sides, then expands to a blotch with frass in scattered irregular particles or liquidy arcs.

Puparium. Reddish-brown; formed outside the mine.

Phenology and voltinism. This species is evidently multivoltine. Larvae have been collected in late April (AR), early June (IL), late June (IL), and mid-July (ON), with adults emerging 14–22 days later. All specimens of the type series, reared in Indiana, were labeled with dates in September, perhaps referring to adult emergence times, but this is unclear (Frick 1956).

Distribution. USA: *AR, [IA], *IL, IN (Frick 1956), [MI, MN, ND, NE, PA, TX, VA, WI]; * Canada: ON. Frick’s (1956) type series included caught specimens from across Canada (including ON), and in the eastern USA south to Kansas and Virginia (including MI, PA, and WI), but Spencer (1969a) found the Canadian specimens he examined to be misidentified. Spencer & Steyskal (1986) apparently were likewise unable to verify any of Frick’s distribution records, listing only Indiana and “not Quebec.”

Comments. This is the only Calycomyza species known to feed on Boraginaceae. The adult can be characterized by a number of features, but some material may not be diagnosable using existing keys due to variation in external coloration—the male reared from Myosotis has an orbit that is not dark to the anterior fronto-orbital, but only to the base of the anterior ors, with only minute spots present at the base of the ori. Similar coloration is seen in the Arkansas female reared from Andersonglossum, which is here included on the basis of its host family. Aside from this, the Myosotis -reared male has a dark-haired calypter, a dark, subshining notum, and a small discal cell (length of ultimate section of vein M 4 divided by penultimate section 2.0–2.3).As usual, however, the male genitalia (Figs. 342–346) are most diagnostic: the hypophallus is fused to the basiphallus and subquadrate in shape with a deep distomedial emargination; the paraphallus is flared apically; the mesophallus is very narrow and slightly downcurved; the distiphallus is upturned and subquadrate in profile with a very small, narrow basal stem. Other species with a plate-like hypophallus have the structure narrower and rarely as apically notched, and the distiphallus differs in shape.