Pest Fruit Flies of the World – Larvae
Pterandrus flavotibialis Hering, Pterandrus rosa var. fasciventris Bezzi
Natal fruit fly, Natal fly. Body length 7.7–9.6mm; slender, elongate, tapering anteriorly, or stout, elongate, tapering anteriorly (?). Integument unsclerotized, entirely whitish to yellowish. Caudal ridge present. Mature larvae able to jump (?).
Head. Head of normal shape; cephalic lobes moderately developed, or slightly developed. Antenna 2-segmented. Stomal organ: primary lobe small, round; number of peg sensilla three, or four or more (small, peg-like); peg sensilla unbranched, or with few short branches; other peg-sensilla-like structures absent. Stomal region: secondary lobes present, short, leaf-like; number of secondary lobes 6; margins of secondary lobes all entire; sclerotized stomal guards absent. Oral ridges present; number of oral ridges 8–12; margins serrate, or scalloped (short, bluntly rounded teeth). Accessory plates absent. Elongate, finger-like lobes arising above mandibles absent. Median oral lobe absent or not protruding. Labium broad.
Cephalopharyngeal skeleton. Mandibles: subapical teeth present (minute: SEM or slide only); tooth minute, visible only in slide mounts or by SEM; with a single ventral tooth; base elongate, forming a more oblique angle. Parastomal bars elongate, free from hypopharyngeal sclerite. Dental sclerites present, posterior to mandibles.
Spinules and creeping welts. Dorsal spinules on segments T1-A1 (/5: these 2 specimens in the sample also had a stronger subapical tooth, and differently shaped anterior spiracles, and larger posterior spiracles, and are now considered as possibly representing a different species).
Caudal segment (a8) and anal lobes. Sensilla on caudal segment 10 pairs, with at least 7 pairs visible under dissecting microscope. Dorsal caudal sensilla obvious, sessile or on separate papillae or tubercles. Intermediate caudal sensillum I3 obvious, but not on a papilla or tubercle. Lateral caudal sensillum obvious, but not on a papilla or tubercle. Intermediate caudal sensilla I1a&b obvious, on a single papilla or tubercle, bifid apically. Ventral caudal sensilla absent or visible only with great difficulty, or obvious, but not on a papilla or tubercle (2 pits, 1 papilla). Anal lobes plainly visible, but not strongly protuberant; simple (/2;?).
Anterior spiracles. Anterior spiracle elevated, margin convex to straight (flat). Anterior spiracular tubules 7–11 (n=30, LEC); in a single uniform row.
Posterior spiracles. Posterior spiracular area not distinctly set off from caudal segment. Posterior spiracles: average length of dorsal and ventral rimae 65–82µm; slits 2.76–3.4x longer than wide (one specimen is 3.8 for one slit; gestalt impression is 2.5 for most). Dorsal spiracular processes with numerous trunks arising from a short or semicircular base (medium processes). Number of dorsal spiracular processes 8–9. Number of ventral spiracular processes 9–10. Number of lateral spiracular processes 3–7. Basal width of spiracular processes 10–15µm. Dorsal and ventral spiracular processes: average number of tips 11–12 (range 10–14, n=2). Dorsal and ventral spiracular processes: ratio of number of tips to number of trunks 1.1–1.5.
Host plants. Anacardiaceae (mango), Annonaceae (custard-apple, ?soursop), Apocynaceae (natal plum), Cactaceae (?Opuntia), Caricaceae (papaya), Cecropiaceae (wild), Clusiaceae (imbe, mangosteen), Combretaceae (tropical almond), Ebenaceae (?persimmon), Euphorbiaceae (wild), Flacourtiaceae (?kei apple), Lauraceae (avocado), Loganiaceae (wild), Moraceae (fig), Musaceae (?Musa), Myrtaceae (guava, strawberry guava, Surinam cherry, Syzygium spp.; & wild), Oxalidaceae (carambola), Podocarpaceae (wild), Rhamnaceae (jujube), Rosaceae (apple, apricot, loquat, peach, pear, plum, quince; ?blackberry), Rubiaceae (coffee & wild), Rutaceae (orange (sour, navel, Valencia), tangerine, & wild; ?grapefruit), Sapindaceae (lychee), Sapotaceae (sapodilla (Manilkara zapota), ?white star apple, Chrysophyllum; & wild), Solanaceae (tomato, tabasco pepper), Sterculiaceae (cacao), Vitaceae (wine grape).
Part of plant attacked: fruit.
Biogeographic region. Afrotropical (Africa, Mauritius, Reunion).
Specimens examined. Based on specimens from SOUTH AFRICA: ex culture, Brian Barnes: (n=40+; NMNH, TAMU).
Sources of data and SEM numbers: rev. i96.
Illustrations. • Cephalopharyngeal skeleton, head, spiracles. • Head (anteroventral) SEM. • Stomal organ SEM. • Head (lateral) SEM. • Anterior spiracle SEM. • Caudal segment (posterior) SEM. • Posterior spiracles SEM. • Caudal segment (lateral) SEM. • Anal lobes SEM.
Cite this publication as: ‘L.E. Carroll, A.L. Norrbom, M.J. Dallwitz, and F.C. Thompson. 2004 onwards. Pest fruit flies of the world – larvae. Version: 8th December 2006. http://delta-intkey.com’.