| | Pest fruit flies of the world |
Dacus melanotus Coquillett, Dacus rarotongae Froggatt
Body. Body predominantly black or dark fuscous.
Head. Number of frontal bristles two pairs. Number of orbital bristles one pair. Anterior orbital bristle of male normal, unmodified. Posterior orbital bristles reclinate; acuminate. Ocellar bristles absent or minute, like setulae. 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 undulating, convex above, concave below; with distinct antennal grooves and carina, or 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 considerably longer than face. Scape, pedicel, and first flagellomere scape and pedicel short, first flagellomere elongate. First flagellomere as long as face; rounded apically. Arista longer than first flagellomere; bare or with hairs distinctly shorter than greatest aristal width. 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 absent. Presutural dorsocentral bristle absent. Presutural supra-alar bristle absent. Postsutural supra-alar bristle present. Acrostichal bristle present. Postsutural dorsocentral bristle absent. Intra-alar bristle present, well developed, similar to postalar bristle. Intrapostalar bristles absent. Number of scutellar bristles one pair. The single pair of scutellar bristles apical. Anterior notopleural bristle present. Posterior notopleural bristle(s) acuminate. Number of outstanding anepisternal bristles one. Katepisternal bristles absent. Anepisternal bristles dark, brown to black. Long, erect setulae on laterotergite absent. Scutal setulae acuminate and pale. Scutellum densely setulose. Setulae on scutellum short, decumbent; unicolorous, acuminate. Transverse suture with the lateral branches wide apart. Complete sclerotized postcoxal metathoracic bridge present. Scutum fuscous (teneral), or black; without a large dark central stripe which broadens basally. Postpronotal lobe entirely pale whitish or yellowish, or posterior one-half to two-thirds pale whitish or yellowish. Posterior half of notopleuron same as ground color. 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 absent or indistinct. Distinct pale vertical anepisternal stripe extending to postpronotal lobe. Katepisternite with pale yellowish or whitish spot present and distinct, or absent or indistinct. Transverse suture without distinct stripe or spot. Katatergite with pale yellowish or whitish spot present and distinct. Anatergite with pale yellowish or whitish spot present and distinct. Subscutellum uniformly black. Mediotergite uniformly brown (teneral), or uniformly black. Scutum microtrichia in discrete pattern due to bare areas or completely absent; microtrichia absent or at most present on or lateral to postsutural lateral white stripe, along posterior margin, and/or along transverse suture. 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; entirely black; 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, or at least one femur markedly darker in apical part than in basal part; dark mark on fore femur 100% of length of femur; dark mark on middle femur 100% of length of femur; dark mark on hind femur 100% of length of femur.
Wings. Wing partly bare. Cell bc microtrichia absent. Cell c microtrichia present in apical area. Cell dm bare on less than basal one-third. Dense microtrichia at end of vein A1+CuA2 in male present. Dominant wing pattern costal-banded (faint). Wing pattern mostly yellowish. Dark longitudinal streaks through basal cells absent. Costal band colored from Sc to beyond R4+5. Apex of costal band distinctly expanded into a spot, or not distinctly expanded. Costal band not extending below R2+3; all one color. Crossvein r-m hyaline, or covered by short, diffuse infuscation (very faint). Crossvein dm-cu hyaline, or infuscated along entire length, but not reaching posterior margin of wing (very faint). Crossveins r-m and dm-cu not both covered by a single crossband. Cell r2+3 apical to r-m entirely infuscated. Anal band present, reaching nearly to wing margin along cell cup extension (very faint). Cell r1 and r2+3 without darker spots within the pattern. Intercalary band absent. Subbasal crossband absent. Ratio of width of apical band in cell r4+5 to length of r-m 0.25–0.33. Anterior apical crossband contiguous with costa over entire length, without marginal hyaline band or spots apically in cells r1 and r2+3. Anterior apical band or costal band not extended to vein M. Posterior apical crossband absent. Discal band transverse, or oblique in anterobasal-posteroapical direction, or absent. Outstanding costal spine(s) at subcostal break absent. Ratio of length of costal section 3 to costal section 4 0.67. Ratio of pterostigmal length to width 7. 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 dense over at least proximal section; ventral setation present. Distance between crossvein r-m and costa shorter than r-m. R-m crossvein on cell dm at or near middle of cell dm. Cell bm broad, parallel-sided; ratio of length to width 2; ratio of width to cell cup width 2. Vein M distally curved anterad. Cell dm widens apically gradually from base. Posterodistal corner of cell dm distinctly acute, or approximately a right angle. Cell cup extension or lobe present, vein CuA2 abruptly bent; longer than vein A1+CuA2; with parallel margins.
Abdomen. Abdomen ovate or parallel sided. Abdominal tergites separate. Abdomen in lateral view arched, dome-like, rather rigid. Abdominal tergite 1 broader at apex than at base; without a prominent hump laterally. Pecten of dark bristles on tergite 3 of male present. Tergal glands on tergite 5 present. Abdominal tergite 5 normal. 6th tergite of female normally concealed; shorter than 5th. Abdominal setulae acuminate and pale. Abdominal microtomentum uniform, or absent. 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; without dark brown transverse bands.
Male terminalia. Posterior lobe of surstylus short or absent.
Female terminalia. Syntergosternite 7 straight; shorter than preabdomen; flattened. Ratio of syntergosternite 7 to abdominal tergite 5 1. Dorsobasal scales of eversible membrane about as large as other scales. Aculeus tip gradually tapering, needle-like, with flat cross-section; fused to main part of aculeus, not movable; 0% serrated; not serrate. Two sclerotized spermathecae. Spermathecae tight-set coils.
Miscellaneous. Male attractant: Cue-Lure.
Australasian-Oceanian. Cook Is.
Dacinae. Dacini.
Illustrations. • Habitus male (dorsal), wing.
We advise against extracting comparative information from the descriptions. This is much more easily achieved using the DELTA data files or the interactive key, which allows access to the character list, illustrations, full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting or lacking specified attributes, and distributions of character states within any set of taxa. See also Guidelines for using data taken from Web publications.
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: 2nd April 2019. delta-intkey.com’.
