Bactrocera (Bactrocera) invadens Drew, Tsuruta & White, 2005

Drew, R. A. I., Romig, M. C. & Dorji, C., 2007, Records Of Dacine Fruit Flies And New Species Of Dacus (Diptera: Tephritidae) In Bhutan, Raffles Bulletin of Zoology 55 (1), pp. 1-21 : 4

Bactrocera (Bactrocera) invadens Drew, Tsuruta & White

Bactrocera (Bactrocera) invadens Drew, Tsuruta & White, 2005: 149 . Holotype male in BMNH.

Material examined. – BHUTAN: 19 males, Phuentsholing , 6 May.2000, coll. S. Thapa ; 2 males, Phuentsholing 10 km, 10 Jun.2000, coll. S. Thapa ; 1 male, Rimchu 1, 28 Jun.2000, coll. C. Dorji et al.; 1 male (5 Jul.2000), 1 male (26 Jul.2000), 1 male (16 Aug.2000), Rimchu 1, C. Dorji; 3 males, Rimchu , 17 May.2001 , coll. R. Drew & M. Romig ; 1 male, Rimchu 2, 28 Jul.2000, coll. C. Dorji ; 1 male, Lingmethang 11 km, 1100 m, subtropical forest, 9 Jun.2001, coll. Brian Fletcher ; 1 male, Gelephu , Purana Bastey, 23 Nov.2004, coll. Maha Prasad & Karma Namgyel. All specimens attracted to methyl eugenol. Specimens in NPPC and QDPI.

Diagnosis. – A medium sized species; face fulvous with a pair of medium to large oval black spots; scutum with base colour red-brown with variable dark fuscous to black patterns (in occasional specimens the scutum base colour is black), postpronotal lobes and notopleura yellow, mesopleural stripe reaching midway between anterior margin of notopleuron and anterior npl. seta dorsally, a pair of broad parallel sided lateral postsutural vittae ending at or just behind ia. seta, medial postsutural vitta absent; setae: sc. 2; prsc. 2; ia. 1; p.sa. 1; a.sa. 1; mpl. 1; npl. 2; scp. 4; scutellum yellow except for narrow dark basal band; legs with femora entirely fulvous; wings with cells bc and c colourless, microtrichia in outer corner of cell c only, narrow fuscous costal band confluent with R 2+3 and remaining narrow around costal margin to end just beyond extremity of R 4+5, a narrow pale fuscous cubital streak, supernumerary lobe weak; abdominal terga III-V orange-brown with a ‘T’ pattern consisting of a narrow transverse black band across anterior margin of tergum III which expands to cover lateral margins, a narrow medial longitudinal black band over all three terga, narrow dark fuscous to black lateral margins on terga IV and V, dark orange-brown shining spots on tergum V.

Attractant. – Methyl eugenol.

Distribution. – Sri Lanka, Central Africa. New record for Bhutan.

Hosts. – Recorded from guava, mango, citrus, papaya, and some wild hosts in Africa (see Drew et al., 2005).

Remarks. – This species was recently described ( Drew et al., 2005) after it invaded central Africa from Kenya through to Ghana. It is proving to be a major pest in the countries it has invaded and has probably originated in Sri Lanka. It is similar to Bactrocera dorsalis (Hendel) , Bactrocera kandiensis Drew & Hancock and Bactrocera rubigina Wang & Zhao. It differs from B. dorsalis in having a red-brown scutum occasionally with dark patterns, narrow lateral postsutural vittae and a longer male aedeagus. It differs from B. kandiensis in having a smaller bare colourless area adjacent to cell bm in the wing and from B. rubigina in having a narrower costal band not overlapping R 2+3, a more distinct dark ‘T’ pattern on abdominal terga III-V, shining spots on tergum V pale coloured and males attracted to methyl eugenol.