Liriomyza carphephori spec. nov.

(Figs. 15–16, 41–43, 90–93)

Holotype. NORTH CAROLINA: Scotland Co., Laurinburg, St. Andrews University, 29.vi.2016, em. 17– 25.vii.2016, T.S. Feldman, ex Carphephorus bellidifolius, # CSE2772, CNC653930 (1♂).

Paratypes. MASSACHUSETTS: Berkshire Co., Sheffield, 9.vii.2014, em. by 28.vii.2014, C.S. Eiseman, ex Bidens frondosa, # CSE1210, CNC384879 (1♀); Bristol Co., Easton, 42.006363, -71.086379, 12.viii.2013., em. 30.viii.2013, C.S. Eiseman, ex Mikania scandens, # CSE851, CNC392632 (1♀); same collection data, em. 11.iv.2014, # CSE1073, CNC384795 (1♀); Franklin Co., Northfield, 276 Old Wendell Rd. (42.646967, - 72.424863), 8.x.2016, em. 2–16.v.2017, C.S. Eiseman, ex Bidens frondosa, # CSE3618, CNC939683–939686 (1♂ 3♀); NORTH CAROLINA: Durham Co., Durham, Leigh Farm Park, 10.vii.2017, em. 23–25.vii.2017, T.S. Feldman, ex Bidens bipinnata, # CSE4000, CNC939778–939780 (2♂ 1♀, CNC); Scotland Co., Laurinburg, St. Andrews University, 29.vi.2016, em. 17–25.vii.2016, T.S. Feldman, ex Carphephorus bellidifolius, # CSE2772, CNC653929, CNC653931–653933 (2♂ 2♀); VERMONT: Rutland Co., West Haven, Helen W. Buckner Memorial Preserve (43.576347, -73.411995), 1.x.2016, em. 18.v.2017, C.S. Eiseman, ex Bidens frondosa, # CSE3682, CNC940121 (1♀, head missing).

Etymology. The specific epithet refers to one of the host plants, Carphephorus Cass. (Asteraceae).

Hosts. Asteraceae: Bidens bipinnata L., B. frondosa L., Carphephorus bellidifolius (Michx.) Torr. & A. Gray, Mikania scandens (L.) Willd.

Leaf mine. (Figs. 41–43) On Carphephorus, the long, whitish, entirely linear mine may be formed on either leaf surface; it is frequently formed mostly on the lower surface (Fig. 42), switching to the upper surface toward the end (Fig. 43). Frass is in black, beaded or continuous strips. Mines on Bidens (Fig. 41; previously discussed by Eiseman & Lonsdale (2018) under Liriomyza sp. 3 and illustrated in their Fig. 160) are confined to the upper surface and invariably begin at the apex of a leaflet, where they are often highly contorted before meandering elsewhere in the leaf. Mines of both types have been found together on Mikania (discussed by Eiseman & Lonsdale (2018) under Liriomyza sp. 5 and illustrated in their Fig. 162). The females treated as Liriomyza spp. 3 and 5 by Eiseman & Lonsdale (2018) are included here as paratypes of L. carphephori.

Puparium. (Fig. 16) Yellow to orange-yellow; formed outside the mine.

Distribution. USA: MA, NC, VT. Similar leaf mines on Bidens have been photographed in New York (Dombroskie 2018).

Adult description. Wing length 1.4–1.6mm (♂), 1.8–1.9mm (♀). Length of ultimate section of vein M 4 divided by penultimate section: 2.2–3.0. Costa extending to M 1. Eye height divided by gena height: 5.6–7.0. First flagellomere small, rounded, slightly narrow with small apical tuft of longer hairs. Notum shining.

Chaetotaxy: Two ors, two ori (sometimes three on one side). Ocellar and postvertical setae subequal to frontoorbitals. Four dorsocentral setae, strongly decreasing in length anteriorly. Four rows of acrostichal setulae.

Coloration: (Fig. 15) Setae dark brown. Head yellow with back of head above foramen, clypeus, ocellar tubercle and posterolateral margin of frons (not reaching setae) dark brown; posterior margin of eye with very narrow yellow line; vertex behind tubercle narrowly light brown. Scutum dark brown with complete lateral yellow stripe excluding spot on postpronotum; dark scutal spot sometimes with narrower, fainter connection to scutellum, and posterolateral margin with yellow notch in front of posterior dorsocentral and intra-alar setae that may surround setal bases. Lateral dark brown spot on scutellum sometimes vestigial. Mediotergite dark brown, anatergite yellow with anteroventral region brown, and katatergite yellow with posterior margin brown. Pleuron mostly yellow; anepisternum with small weak anteroventral spot that may sometimes be more distinct and circular; anepimeron with limited brown anterior mottling; meron brown ventrally; katepisternum with brown ventral region not reaching base of seta. Calypter margin and hairs light brown. Haltere yellow. Legs yellow with coxae narrowly brown basally, tarsi brownish, and tibiae light brown with base paler, with anterior tibiae almost yellow and hind tibia darker. Abdominal tergites brown with wide lateral yellow stripe partially visible dorsally; brown stripe narrowest on tergite 5; epandrium brown. Pigment darker and more distinct in female.

Genitalia: (Figs. 90–93) Surstylus with two spines. Distal section of ejaculatory duct swollen and pigmented. Phallophorus with narrow venter and long, dark dorsal plate. Basiphallus plate left lateral to dorsal, base relatively wide and pointed, and left distal corner lightly sclerotized and produced to a point past paraphallus. Paraphallus very small, rod-like. Hypophallus rod-like with apical hairs. Mesophallus short, dark and with anterioventrally produced carina; distiphallus length twice width, slightly compressed dorsoventrally, with complete, broadly open ventral suture, apparently hollow with few medially directed spinules emerging from inner-distal margin laterally. Ejaculatory apodeme narrow, small, barely widened to pale apex; sperm pump with sclerotized venter.

Comments. Liriomyza carphephori is a relatively pale species, with the frons around the vertical setae, the anepisternum (faded brownish spot), the posterolateral region of the scutum and the femora being yellow. There are also four strong fronto-orbitals and four rows of acrostichal setulae on a shining scutum. The phallus is most diagnostic however: the paraphalli are small, the basiphallus is downturned with a relatively strong distolateral process, the mesophallus is very short with a large ventral carina, the distiphallus is cylindrical and broadly split ventrally, and the distiphallus is empty—that is, there are no internal structures, including the short fringed tubules typical of most Liriomyza.

This is the first record of any agromyzid feeding on Carphephorus. In North Carolina, TSF has rarely found mines of Liriomyza carphephori on Bidens, whereas they are abundant on Carphephorus from May through midsummer where this plant occurs. In New England, CSE has found larvae on B. frondosa in July as well as in early October after the leaves have turned entirely red; larvae were found on Mikania scandens in August. Contorted mines in the apices of Ageratina altissima (L.) R.M. King & H. Rob. leaves likely also represent L. carphephori; CSE has found occupied examples in Ohio in mid-September.