Pest Fruit Flies of the World
Rhacochlaena japonica Ito
Body. Body elongate; predominantly orangish to brown.
Head. Number of frontal bristles three pairs. Number of orbital bristles one pair. Anterior orbital bristle of male normal, unmodified. Posterior orbital bristles reclinate; acuminate. Ocellar bristles short, distinctly shorter than 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. Male and female head width the same. Frontofacial angle about equal to a right angle and angular. Face concave; 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 round, about as high or slightly higher than long. Antenna about as long as face. Scape, pedicel, and first flagellomere all relatively short. First flagellomere shorter than face; rounded apically. 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; dark. Outer scapular bristle present and distinguishable from surrounding vestiture; dark. Postpronotal bristle present. Presutural dorsocentral bristle absent. Presutural supra-alar bristle absent. Postsutural supra-alar bristle present. Acrostichal bristle present. Postsutural dorsocentral bristle present; bristles about midway between postsutural supra-alar and post-alar bristles. 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. Katepisternal bristles present. Long, erect setulae on laterotergite present. Scutal setulae acuminate and pale. Scutellum 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; without a large dark central stripe which broadens basally. Postpronotal lobe entirely pale whitish or yellowish. Posterior half of notopleuron pale whitish or yellowish, or same as ground color. Scutum dorsad of notopleuron of the ground color, not whitish or yellowish (indistinct, fulvous). 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, light colored. Discrete pale horizontal stripe along upper anepisternum present and distinct, extending from postpronotal lobe to wing base, or absent or indistinct. 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 uniformly black. Mediotergite uniformly brown. Scutum entirely microtrichose, microtrichia evenly distributed, or at most with small presutural, medial bare area. Dorsum of scutellum flat or slightly convex, not swollen. Scutellum normal; without a dark and pale pattern (at most a narrow dark basal line); with no isolated dark spots; without black mark; without mark.
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 all entirely of one color; dark mark on fore femur 0% of length of femur; dark mark on middle femur 0% of length of femur; dark mark on hind femur 0% of length of femur.
Wings. Wing partly bare. Cell bc microtrichia present in apical area only, or covering whole cell (anterior portion). 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 with bands extensively fused, distorted, or greatly reduced. 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. Crossveins r-m and dm-cu not both covered by a single crossband. 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 present, distinct from apical band. Subbasal crossband present (faint). Subbasal and discal crossbands not joined. Ratio of width of apical band in cell r4+5 to length of r-m 2–3. Anterior apical crossband partly to entirely separated from costa by marginal hyaline band or spots. Posterior apical crossband present. Costal and discal bands not joined on vein R4+5. Discal band transverse, or oblique in anterobasal-posteroapical direction, or absent. Discal and apical crossbands not directly joined. Discal and subapical crossbands not joined. Discal and subapical bands not 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 (short), or absent. Ratio of length of costal section 3 to costal section 4 0.5. Ratio of pterostigmal length to width 2–2.5. 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 sparse over both sections; 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 curved anterad, or straight. Cell dm widens apically gradually from base. Posterodistal corner of cell dm approximately a right angle. 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 acuminate and dark, or acuminate and pale. Abdominal microtomentum uniform, or in bands. Abdominal tergites 3–5 predominantly yellow to orange brown. Abdominal tergites without medial dark stripe; not brown with medial T-shaped yellow mark; with broadly contiguous dark areas on lateral margins of T3-T5, or without isolated dark areas on lateral margins of T3-T5; without dark brown transverse bands.
Female terminalia. Syntergosternite 7 straight; shorter than preabdomen; base without a laterally projecting flap; flattened. Ratio of syntergosternite 7 to abdominal tergite 5 2. Dorsobasal scales of eversible membrane about as large as other scales (?). Three sclerotized spermathecae. Spermathecae spherical, or ovoid, or elongate.
Miscellaneous. Male attractant: none known.
Palearctic. Korea, Japan (Hokkaido, Honshu).
Illustrations. • Wing. • Head (lateral).
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’.