Ophiomyia cophina Eiseman & Lonsdale, sp. nov.

(Figs. 30, 133, 134, 290–294)

Holotype. USA. MASSACHUSETTS: Franklin Co., Northfield, 42.652234, −72.430470, 25.x.2019, em. 14.iii.2020, C.S. Eiseman, ex Oclemena acuminata, # CSE6052, CNC1904788 (1♂).

Paratypes. USA. MASSACHUSETTS: Franklin Co., New Salem, Quabbin, Gate 33, 19.x.2018, em. 28.iii– 1.iv.2019, C.S. Eiseman, ex Solidago bicolor, # CSE5152, CNC1990567, CNC1990568 (1♂ 1♀).

Tentatively identified material: CONNECTICUT Litchfield Co., Norfolk, Aton Forest Headquarters, 42.026659 −73.136776, 26.viii.2023, em. 30.viii.2023, C.S. Eiseman, ex Solidago bicolor, # CSE8475, CNC2104734 (1♀), MASSACHUSETTS: Franklin Co., Northfield, 42.646958, −72.425076, 20.vii.2020, em. 3.viii.2020, C.S. Eiseman, ex Solidago canadensis, # CSE6472, CNC1904789 (1♀).

Photographed mines. VERMONT: Orange Co., Strafford, 43.839123, −72.381126, 3.viii.2024, L. Smith, mine with puparium on Solidago bicolor (iNat 234772147).

Etymology. The specific epithet (from L. cophinus —basket) refers to the male’s distinctive large, coffin-shaped distiphallus.

Hosts. Asteraceae: Oclemena acuminata (Michx.) Greene, Solidago bicolor L., [S. canadensis L.].

Larval biology. (Figs. 133, 134) The larva forms a whitish (turning brown) stem mine with frass in fine black grains.

Puparium. Black in the overwintering generation, and otherwise appearing pale blue when occupied; formed just beneath the stem epidermis, with the anterior spiracles protruding.

Phenology and voltinism. The tentatively identified females emerged in early and late August from puparia collected in mid-July and late August. The other known specimens were found as pupae in mid- to late October and emerged as adults the following spring.

Distribution. USA: [CT], MA, [VT].

Adult description. Wing length approximately 2.1–2.3 mm (♂), 2.1–2.4 mm (♀). Length of ultimate section of vein M 4 divided by penultimate section: 0.7–0.8. Eye height divided by gena height: 6.3–8.6. First flagellomere small, rounded; distal margin with slightly longer hairs. Ocellar triangle reaching to level of anterior ors or posterior ori. Vitta minutely textured. Orbital plate narrow, faintly delimited, narrowest anteriorly. Lunule shallow, wide, without medial groove. Lower half of face with shallow carina, dorsum with ovate bulb that is slightly wider than space between antennal bases. Vibrissal angle about 60°. Cheek narrow. Clypeus with narrow anteromedial extension that has corners slightly produced. Notum with light dusting of pruinosity, almost shining.

Chaetotaxy: Two ori (anterior seta almost flat on frons), two ors. One row of orbital setulae. Postvertical and ocellar setae subequal to fronto-orbitals (slightly longer in Solidago -reared male) but thinner, with ocellar slightly shorter. Vibrissal fasciculus well-developed, curved upward; Oclemena -reared male with vibrissal setae separating apically, appearing “frayed”. Two strong dorsocentral setae, with second slightly shorter. Eight rows of acrostichal setulae, ending in one pair of setulae behind second dorsocentral. Katepisternum sometimes with extra smaller seta. Mid tibia with one posteromedial seta (none in tentatively identified female from Connecticut).

Coloration: Setae black. Body mostly brown; head, scutellum and most of central disc of scutum dark brown; outer margin of scutum and postpronotum with limited yellowish-brown mottling. Calypter margin pale, hairs dark brown.

Genitalia: (Figs. 290–294) Epandrium shallow, fused to surstylus anteroventrally. Surstylus small, rounded, wider than high; with three short irregular rows of tubercle-like setae on inner surface. Cercus well-developed. Hypandrium subtriangular, sides slightly rounded and apex slightly extended as short, wide apodeme. Phallophorus relatively short, narrowest as base, produced anteroventrally; separated from mesophallus by slightly more than its own length. Basiphallus sclerotized dorsobasally, with atrophied left lateral extension and long, apically hooked right lateral branch that reaches level of mesophallus. Mesophallus narrow, slightly curved, inserted past midpoint of distiphallus; base of distiphallus extending far past base of mesophallus. Distiphallus very large, in ventral view appearing coffin-shaped with rounded apex and narrowed base, and with ventral sulcus with swollen margins that are produced as small carinae; lateral surface internally with pointed ridges that may be short to long and branched; in lateral view, surface appearing bumpy, dorsum open on distal ⅗ with short central process and dorsoapical tubule emerging from within cavity. Ejaculatory apodeme well-developed, with pale asymmetric blade that extends along one side of long stem; sperm pump with strong transverse sclerite that is upturned at ends.

Comments. While externally indistinguishable from most Ophiomyia with a fasciculus on a 60° vibrissal angle, the phallus of this species is unique and highly diagnostic, being large and coffin-shaped in ventral view.

Five entedonine eulophid wasps (CSE8963, CNC, iNat 323802117) emerged from the puparium collected in Vermont.