Bactrocera (Bactrocera) digressa Radhakrishnan

David, K. J. & Ramani, S., 2011, An illustrated key to fruit flies (Diptera: Tephritidae) from Peninsular India and the Andaman and Nicobar Islands, Zootaxa 3021, pp. 1-31 : 16

Bactrocera (Bactrocera) digressa Radhakrishnan

Bactrocera (Bactrocera) digressa Radhakrishnan, 1999 . Rec.Zool.Surv. India, 97(4):1. Holotype ♀. India (Tamil Nadu: Salem dist., Shevroy Hills, Semmanathan ) (ZSI) [not examined]

Bactrocera (Daculus) yercaudiae Drew, 2002 . Raffles Bull.Zool., 50(2): 346. Holotype ♂. India (Tamil Nadu: Yercaud, 15 Km from Yercaud ) (BMNH) [not examined]; syn.nov.

Material examined

INDIA: Karnataka: 11 ♂ , Bangalore , 916m, 10.vii.1989, S. Ramani; 2 ♂ , same data except 11.vii.1989; 1 ♂ , same data except 4.ii.1989; 2 ♂ , same data except 3.vii.1988, G. Bhat; 3 ♂ , Bangalore, Hessaraghatta , 916m, 14.iii.1987, G. Bhat; 3 ♂ same data except 23.i.1988; 2 ♂ same data except 9.vii.1988; 2 ♂, 1♀ , Bangalore , GKVK, 4.ii.2008, David, K. J.; 1 ♂ , same data except 20.i.2008; 1 ♂ , same data except 8.vi.2008, Sudha, M.; 1 ♂ , Gouribidanur , 29.vi.2009, Praveen; 1 ♂ , Mandya , 24-30.vii.1989, Gubbaiah; 2 ♂ , Tamil Nadu, Yercaud , 3.vii.1992, S. Ramani ( UASB); 2 ♀ , Karnataka, Gowribidanur, Kolar , 23.vii.07, Naveen Kumar ( NBAII) .

Radhakrishnan (1999) described Bactrocera digressa based on two females collected from Salem district, Tamil Nadu. The diagnostic characters of the species are reddish brown scutum, bifid aculeus tip, absence of acrostichal and anterior supra-alar setae. Later, Drew and Raghu (2002) described Bactrocera (Daculus) yercaudiae based on males collected from Yercaud, Tamil Nadu and Bangalore which responded to cue lure. Perusal of original description of the two species showed complete congruence of characters except costal band, which was mentioned as confluent with vein R 2+ 3 in Bactrocera digressa and slightly overlapping R in B. yercaudiae . Material mentioned above which were keyed out as Bactrocera yercaudiae were examined to confirm the identity. Examination of aculeus tip of the females revealed that it has a bifid aculeus and all the characters are in concordance with that of B. digressa except for a slightly overlapping costal band which might have been overlooked by Radhakrishnan (1999) because it is very faint beyond vein R 2+3. Hence we propose B. yercaudiae as a junior synonymn of B. digressa . Since all the Asian species in subgenus Daculus are aberrant Bactrocera s.str. and true Daculus are African, B. digressa is retained in subgenus Bactrocera ( Copeland et al., 2004) . As per ICZN rules, Bactrocera digressa Radhakrishnan is the valid name. Three females have been reared from fruits of Alangium lamarkii collected from Yercaud, Tamil Nadu and are deposited in BMNH (Ian M. White, pers. comm.)