Bactrocera (Bactrocera) invadens Drew, Tsuruta and White

Singh, Maneesh Pal, Sharma, Isha, Hancock, David Lawrence & Prabhakar, Chandra Shekhar, 2022, A new species of Bactrocera Macquart and a new distribution record of Dacus Fabricius (Diptera: Tephritidae: Dacinae) from India, Zootaxa 5168 (2), pp. 237-250 : 245-249

Bactrocera (Bactrocera) invadens Drew, Tsuruta and White

( Figure 5 )

Bactrocera (Bactrocera) invadens Drew, Tsuruta and White, 2005: 149 ; Drew et al. 2007: 4 .

Diagnosis (Male): A medium-sized species (6.55±0.15) with face fulvous or pale brown with two oval black spots in antennal furrows, two frontal setae and one orbital seta, ocellar triangle pale brown to dark, ocellus fuscous, outer vertical seta and medial vertical seta present and dark in colour, a thin row of black postocular setae present on occiput, occiput fuscous, gena fulvous with a seta but no dark subocular spot. Scape and pedicel fuscous, first flagellomere dark fuscous to dark brown. Scutum generally dark orange to red-brown with black lanceolate markings, dark brown to red in some specimens, the medial dark lanceolate marking variable in shape and in some specimens scutum entirely pale or mostly black. Postpronotal lobes and notopleura bright yellow. Postsutural lateral yellow vittae narrow, parallel-sided and end at or just behind intra-alar seta. Scutellum triangular and bright yellow. Anepisternal stripe broader than notopleuron and triangular in shape, katepisternum with a thin, linear yellow marking. Chaetotaxy: 2 scapular setae, 1 anterior notopleural seta, 1 notopleural seta, 1 anepisternal seta, 1post-alar seta, 1 intra-alar seta, 1 prescutellar acrostichal seta. Legs with all femora fulvous, fore and mid tibia fuscous and hind tibia dark fuscous. Wings (5.84±0.21) hyaline, cells bc and c colourless and without microtrichia, except for outer margin of cell c. Costal band narrow and confluent with vein R 2+3, anal streak pale and narrow and a medium-developed anal lobe. Abdomen orange-brown to red-brown with a black T-shaped pattern consisting of a transverse basal band on tergite III and a narrow medial vitta on tergites III-V; the transverse band sometimes covers the lateral margin of tergite III and continues laterally to tergite V; in some specimens the transverse band is absent. Pecten present on tergite III in males and two shiny orange ceromata present on tergite V. Deep posterior emargination present on sternite V of male.

Male Genitalia: Epandrium and surstyli elongate-oval in posterior view. Proctiger membranous, triangular, smaller than epandrium ( Figure 6A ). Medial surstylus longer than lateral surstylus and diminutive or tapering towards apex with a pair of thick, dark, striated prensisetae. Aedeagus 1.98 mm long excluding glans (0.43 mm). Glans tubular, mostly sclerotized with an unpatterned and narrow praeputium. Subapical lobe and basal lobe present, the former reaching above the vesica and with a distinct capitulum ( Figure 6B ) (cf. figs 8G in David and Ramani 2019, as dorsalis ).

Material Examined: 8 ♂, INDIA, Uttarakhand, Pantnagar , 20°02’29”N 79°48’79”E 2.vii.2020, Maneesh; 10 ♂, India, Himachal Pradesh, Solan , Nauni , 30°51’24”N 77°10’17”. 28.vii.2020, Maneesh .

Male Parapheromone: Methyl eugenol.

Host Plants: A wide range of edible, commercial and native fruits ( Drew et al. 2005; Rasolofoarivao et al. 2022).

Remarks: This species belongs in the dorsalis complex and is very similar to B. (B.) dorsalis (Hendel) . It is often regarded as a synonym of the latter (e.g. Schutze et al. 2015) but can be differentiated by the frequent presence of extensive red-brown markings on the scutum and narrower postsutural lateral yellow vittae. The aedeagus and aculeus are also longer than in B. dorsalis and there are differences in phallus structure ( Hancock et al. 2021), the glans being tubular in B. invadens and subovate in B. dorsalis . The species is widespread on the Indian subcontinent and invasive in the Afrotropics. In the Himalayan region it has been definitively recorded from Bhutan ( Drew et al. 2007) and Nepal ( Leblanc et al. 2019, as dorsalis ) and its presence in the northwestern Indian States of Himachal Pradesh and Uttarakhand is confirmed here. True B. dorsalis is not known from the Indian subcontinent and its presence can be confirmed only by examination of the phallus.

Figures

FIGURE 5. Bactrocera (Bactrocera) invadens, Drew, Tsuruta & White (A–L), A–F: Thoracic variations and G–L: Abdominal variations

FIGURE 6. Bactrocera (Bactrocera) invadens, Drew, Tsuruta & White (A–B), A: Epandrum and B: Glans