Pest Fruit Flies of the World
Blueberry maggot, Blueberry maggot fly.
Body. Body plump; predominantly black or dark fuscous, or predominantly orangish to brown.
Head. Number of frontal bristles three pairs. Number of orbital bristles two pairs. Anterior orbital bristle of male normal, unmodified. Posterior orbital bristles reclinate; acuminate. Ocellar bristles long, about as long as frontal bristles. Postocellar bristles present. With both inner and outer vertical bristles. Outer vertical, postvertical and postocellar bristles all acuminate. Postocular bristles acuminate; normal. Genal bristle present. Head higher than long (height 1.1–1.2x length). Male and female head width the same. Frontofacial angle about equal to a right angle and angular. Face concave, or flat; without transverse sulcus, antennal grooves, or carina; shorter than frons; vertical; without dark marks. Parafacial spot absent. Frons and parafacial without small silvery markings. Fronto-orbital plate setulose. Frontal stripe setulose. Eye elongate, considerably higher than long. Antenna considerably shorter than face. Scape, pedicel, and first flagellomere all relatively short. First flagellomere shorter than face; pointed dorsoapically. Arista longer than first flagellomere; pubescent, with hairs about as long as greatest aristal width; hairs both dorsal and ventral. Proboscis short, capitate.
Thorax. Inner scapular bristle present and distinguishable from surrounding vestiture; pale. Outer scapular bristle present and distinguishable from surrounding vestiture; pale. Postpronotal bristle present. Presutural dorsocentral bristle absent. Presutural supra-alar bristle present. Postsutural supra-alar bristle present. Acrostichal bristle present. Postsutural dorsocentral bristle present; bristles aligned with postsutural supra-alar bristles or slightly behind. Intra-alar bristle present, well developed, similar to postalar bristle. Intrapostalar bristles absent. Number of scutellar bristles two pairs. Apical scutellar bristles as long as basals or longer. Anterior notopleural bristle present. Posterior notopleural bristle(s) acuminate. Number of outstanding anepisternal bristles one, or two. Katepisternal bristles present. Anepisternal bristles dark, brown to black. Long, erect setulae on laterotergite absent. Scutal setulae acuminate, mixed dark and pale. Scutellum non-setulose, or sparsely setulose. Setulae on scutellum short, decumbent; unicolorous, acuminate. Transverse suture with the lateral branches wide apart. Complete sclerotized postcoxal metathoracic bridge absent or semimembranous. Scutum fuscous, or black; without a large dark central stripe which broadens basally. Postpronotal lobe entirely pale whitish or yellowish. Posterior half of notopleuron pale whitish or yellowish. Scutum dorsad of notopleuron of the ground color, not whitish or yellowish. Dark lyre-like pattern on scutum absent. Discrete shiny black spots on scutum absent. Median longitudinal black stripe on scutum absent. Number of pale whitish to yellow postsutural stripes zero. Scutum without blackish dorsocentral stripe. Area bordering scutoscutellar suture medially without dark brown spot, brown. Discrete pale horizontal stripe along upper anepisternum present and distinct, extending from postpronotal lobe to wing base. Distinct pale vertical anepisternal stripe absent. Katepisternite with pale yellowish or whitish spot absent or indistinct. Transverse suture without distinct stripe or spot. Katatergite with pale yellowish or whitish spot absent or indistinct. Anatergite with pale yellowish or whitish spot absent or indistinct. Subscutellum uniformly brown, or yellowish to orange-brown medially, with distinct dark spots laterally. Mediotergite uniformly brown. Scutum microtrichia in discrete pattern due to density differences (2 broad lateral microtrichose stripes, slightly fainter in middle of strip; could appear as mediolateral & lateral stripes broadly fused anteriorly). Dorsum of scutellum flat or slightly convex, not swollen. Scutellum normal; with a dark and pale pattern; with no isolated dark spots; with lateral black marks extending apically, leaving apical area pale.
Legs. Femora slender. Fore femur with regular bristles; without ventral spines; with 1 to 3 posterodorsal and 1 posteroventral rows of bristles only. Mid femur and hind femur without spine-like bristles. Middle leg of male without feathering. Femora at least one femur markedly paler in apical part than in middle or basal part; dark mark on fore femur 25–50% of length of femur (dark area on apical part of anterior surface); dark mark on middle femur 80–90–100% of length of femur; dark mark on hind femur 70–80–90% of length of femur.
Wings. Wing partly bare. Cell bc microtrichia covering whole cell. Cell c microtrichia covering whole cell. Cell dm entirely microtrichose. Dense microtrichia at end of vein A1+CuA2 in male absent. Dominant wing pattern cross-banded. Crossbanded wing patterns Rhagoletis-like. Wing pattern mostly brownish. Dark longitudinal streaks through basal cells absent. Crossvein r-m covered by a major crossband. Crossvein dm-cu covered by a major crossband which reaches posterior margin of wing. Cell r2+3 apical to r-m with large hyaline area. Anal band absent, or not reaching nearly to wing margin. Cell r1 and r2+3 without darker spots within the pattern. Intercalary band absent. Subbasal crossband present. Subbasal and discal crossbands joined. Marginal hyaline area in cell r1 absent or indistinct. Ratio of width of apical band in cell r4+5 to length of r-m 1–1.5. Anterior apical crossband partly to entirely separated from costa by marginal hyaline band or spots. Anterior apical band or costal band extended to vein M. Posterior apical crossband absent. Discal band transverse, or oblique in anterobasal-posteroapical direction, or absent. Discal and apical crossbands directly joined. Discal and subapical crossbands joined along anterior wing margin or along vein R4+5. Discal and subapical bands connected along vein R4+5. Subapical and anterior apical crossbands not joined, subapical crossband not reaching costa. Outstanding costal spine(s) at subcostal break present. Ratio of length of costal section 3 to costal section 4 0.4. Ratio of pterostigmal length to width 2.5. Vein R1 dorsal setation without bare section opposite end of vein Sc. Vein Rs dorsal setation non-setulose. Vein R2+3 generally straight. Anteriorly-directed accessory vein emerging from R2+3 absent. Vein R4+5 dorsal setation absent; ventral setation absent or only present on node or close thereafter. Distance between crossvein r-m and costa longer than r-m. R-m crossvein on cell dm at or near middle of cell dm. Cell bm narrow, triangular; ratio of length to width 3; ratio of width to cell cup width 1. Vein M distally straight. Cell dm widens apically gradually from base. Posterodistal corner of cell dm distinctly acute. Cell cup extension or lobe present, vein CuA2 abruptly bent; shorter than vein A1+CuA2; triangular.
Abdomen. Abdomen ovate or parallel sided. Abdominal tergites separate. Abdomen in lateral view flatter, more flexible. Abdominal tergite 1 broader at apex than at base; without a prominent hump laterally. Pecten of dark bristles on tergite 3 of male absent. Tergal glands on tergite 5 absent. Abdominal tergite 5 normal. 6th tergite of female exposed; shorter than 5th. Abdominal setulae mixed dark and pale acuminate (dark & pale setulae on T1+2; dark setulae on T3–5). Abdominal microtomentum in bands. Abdominal sternite 5 of male broad, at least 2x wider than long. Posterior margin of sternite 5 of male with deep V-shaped posterior concavity. Abdominal tergites 3–5 predominantly black. Abdominal tergites without medial dark stripe; not brown with medial T-shaped yellow mark; without isolated dark areas on lateral margins of T3-T5; with dark brown transverse bands which may be interrupted medially.
Male terminalia. Epandrium in posterior view with long outer surstyli, which are more than half as long as epandrium; lateral view with outer surstyli distinctly narrower than epandrium, clearly differentiated. Distiphallus present; without basolateral membranous lobe; with extensive medial sclerotization; without stout, curved, basal spine; without basal setulose rod. Sclerite of vesica of distiphallus absent.
Female terminalia. Syntergosternite 7 straight; shorter than preabdomen; base without a laterally projecting flap; flattened. Ratio of syntergosternite 7 to abdominal tergite 5 0.5. Dorsobasal scales of eversible membrane about as large as other scales. Aculeus length 0.73–0.89 mm. Aculeus tip gradually tapering, needle-like, with flat cross-section; fused to main part of aculeus, not movable; 0% serrated; not serrate. Three sclerotized spermathecae. Spermathecae elongate.
Miscellaneous. Male attractant: none known.
Nearctic. Canada & USA (Wisconsin E to Nova Scotia, S to Texas & Florida).
Illustrations. • Wing.
Cite this publication as: ‘L.E. Carroll, I.M. White, A. Freidberg, A.L. Norrbom, M.J. Dallwitz, and F.C. Thompson. 2002 onwards. Pest fruit flies of the world. Version: 8th December 2006. http://delta-intkey.com’.