Bactrocera (Bactrocera) divenderi Maneesh, Hancock and Prabhakar, 2022

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 : 240-244

Bactrocera (Bactrocera) divenderi Maneesh, Hancock and Prabhakar , sp. n.

( Figures 1–3 )

Bactrocera (Bactrocera) nigrofemoralis: Drew et al. 2007: 4 . Bhutan (misidentification).

Diagnosis: A medium-sized (holotype length 5.94 mm), largely black species fitting in the nigrotibialis complex as defined by Drew and Romig (2013). It most closely resembles B. nigrofemoralis White & Tsuruta in its black face and narrow, linear postsutural lateral yellow vittae but the vittae are longer, reaching or almost reaching the intra-alar setae.

Head: Height 1.42 mm, width 0.92 mm. Frons fulvous to golden, with dark marks at the base of frontal setae that unite to form an X-shaped dark mark on frontal area. Ocellar triangle black. Occiput golden brown with row of 7-8 dark setae. Postocciput black. Dark subocular spot present. Lunule dark black. Face entirely black without round or oval spots, the dark area reaching genal suture. Antennal segments fulvous except flagellomere slightly dark at apex. Arista shiny fulvous basally and black anteriorly. Length of antennal segments 0.26, 0.29 and 0.77 mm. Two frontal, 1 orbital, 2 vertical and 1 genal seta present on each side.

Thorax: Scutum black without pale sutural markings except for a small, triangular red-brown patch at apex of notopleural callus. Postpronotal lobe shiny yellow except black at anterodorsal corner. Notopleural callus yellow. Anepisternal stripe yellow and broad, reaching line of anterior notopleural seta dorsally and separated from narrow yellow mark present on katepisternum. Postsutural lateral yellow vittae narrow (width 0.078 mm), separate from suture and ending at intra-alar setae, narrower than basal band on scutellum. Anatergite and katatergite bright yellow except for basal quarter. Scutellum yellow, subtriangular and with medium-width (0.19 mm) black basal band. Chaetotaxy: 2 scapular setae, 1 anterior notopleural seta, 1 notopleural seta, 1 anepisternal seta, 1 supra-alar seta, 1 post-alar seta, 1 intra-alar seta, 1 prescutellar acrostichal seta and 1 scutellar seta. Post-alar seta distinctly longer (0.51 mm) than intraalar seta (0.22 mm). Fore femora entirely black except for slight paler inner area and apex. Mid femora entirely black except pale basally and apically. Hind femora pale except apical third black. Fore and mid tibiae fuscous, hind tibia black except paler fuscous apically. Mid tibia with an apical black spur. All tarsi entirely fulvous. Wings (4.95 mm) hyaline with narrow costal band, cells bc and c bare except for slight distribution of microtrichia in anterior portion of cell c. Cell r dark with dense microtrichia. Costal band confluent with vein R 2+3 and weakly crosses vein R 4+5 at apex; it is uniformly narrow and not apically expanded. Slight infuscation of microtrichia below R 4+5 and less dense microtrichia distributed all over the wing except for cell bm, basal areas of cells R 4+5 and br and base of anal lobe. Anal streak present in both sexes but broader in males.

Abdomen: Abdomen rounded. Tergite I entirely black except for very narrow thin band near tergite II. Tergite II dark with pale orange transverse band basally that is narrow towards margin and reaches lateral margins of tergite. Tergite III entirely black. Tergites IV and V entirely black except for narrow medial orange patch and black medial stripe; ceromata on tergite V shiny black. Pecten present on tergite III in males. Abdominal sternites fuscous except sternite II pale yellow or pale fulvous. Venter of abdomen with basal half pale fulvous and anterior half light fuscous. Sternite V with a deep concavity on posterior margin.

Male genitalia: Epandrium sclerotized and elongate-oval in posterior view. Epandrium and proctiger with long setae. Proctiger shorter than epandrium and quadrate in shape. Lateral surstylus with small setae. Median surstylus ends in two black and striated prensisetae. Posterior lobe of surstylus short. Aedeagus 2.64 mm long excluding glans (0.33 mm). Glans sclerotized with spiny membrane on dorsal side. Vesica short and subapical lobe elongate (0.15 mm), capitulate and sclerotized.

Female genitalia: Oviscape black and 1.11 mm long. Eversible membrane 1.12 mm long and aculeus 1.27 mm long. Aculeus sharp, chisel-shaped, flat without flange like projection and with 4 pairs of preapical setae, two long and two short. Eversible membrane entirely covered with spicules. Spicules on distal membrane with 7-8 equal-sized slightly blunt projections.

Variation: All characters of paratypes are stable and similar to holotype, with body length 6.037± 0.11 mm and wing length 5.42± 0.15 mm. Abdominal variation was observed in a few paratypes ( Fig.2 ): in some specimens the whole abdomen is black without any pale markings except for the transverse band on tergite II and in some specimens tergites IV and V are black except for a very narrow reddish fuscous patch at the apex of tergite V; in some specimens the medial pale area is broad on tergite IV and also reaches to tergite III and in some specimens sternites II and III are both pale fulvous. No variation was observed in other morphological characters.

Type material: Holotype ♂, Cuelure, INDIA, Himachal Pradesh, Solan, Nauni , 30°51’24”N 77°10’17”. 19.vii.2020, Maneesh. Paratypes: 6 ♀, Prunus persica , INDIA, Himachal Pradesh, Nauni, 30°51’24”N 77°10’17”. 22.vii.2020, Maneesh ; 18 ♂, Cuelure , India, Himachal Pradesh, Nauni , 30°51’24”N 77°10’17”. 27.vii.2020, Maneesh; 12 ♂, INDIA, Prunus persica , Himachal Pradesh, Sirmaur, Sanora, 30°53’23”N 77°13’34”. 19.viii.2020, Maneesh.

Etymology: The species is named after Dr. Divender Gupta (Director of Extension Education, Dr.Y.S.P.U.H.F. Nauni, Solan, Himachal Pradesh) for his guidance in research.

Male Parapheromone: Cue lure.

Host Plant: Peach and Nectarine, Prunus persica (Rosaceae) .

Remarks: This species belongs in the nigrotibialis complex and in general morphology is very similar to B. (B.) nigrofemoralis but can be differentiated by its longer and posteriorly parallel-sided postsutural lateral yellow vittae, which end at or just before the intra-alar setae, not generally well before as in the latter species. Although the postsutural vittae extend close to the intra-alar setae in some specimens of B. nigrofemoralis they are distinctly narrowed or obscured posteriorly and the difference in shape and length is thus considered sufficient to regard this northern Indian population as distinct. There are also possible differences in the male glans: in B. nigrofemoralis the apical expansion of the subapical lobe appears to be larger and fan-shaped (cf. figs 7B in Tsuruta and White 2001; 9A in David and Ramani 2019), but the consistency of this character is uncertain. In the female, there are differences in the spicules of the eversible membrane and shape of the aculeus: B. divenderi possess 7-8 projections instead of 3-4 in B. nigrofemoralis , while the aculeus in B. divenderi is flat laterally without the flange-like projections around the preapical setae present in B. nigrofemoralis (K.J. David, pers. comm.; cf. figs 11H and 13H in David and Ramani 2019). It also occurs in Bhutan, where specimens recorded as B. nigrofemoralis were also noted to have long postsutural vittae ( Drew et al. 2007), identical to those described here for B. divenderi . Specimens recorded from Rawalpindi, Pakistan ( Tsuruta and White 2001, Drew and Romig 2013) have long, parallel-sided postsutural lateral yellow vittae that reach the intra-alar setae (N. Wyatt, pers. comm.) and also belong with B. divenderi . This species is a pest of Prunus persica and during a 4-year survey no other host was recorded in Himachal Pradesh, where it is probably monophagous.

Among the nigrotibialis complex species discussed in this study, only B. (B.) divenderi , B. (B.) nigrofemoralis , B. (B.) nigrotibialis and B. (B.) nigrifacia have been recorded from commercial crops, in families Rosaceae , Myrtaceae , Sapotaceae and Cucurbitaceae respectively, with B.(B.) divenderi probably the only species occurring up to pest level in fields. It is distinct from B.(B.) nigrofemoralis in morphological characters, with the latter species apparently confined to southern regions of India and Sri Lanka.

Bactrocera (B.) zonata was well known previously as a peach pest and it seems likely that B. (B.) divenderi has replaced it from Prunus persica orchards in the Himalayas. Earlier, Gupta et al. (1990) recorded B. (B.) zonata as highly active in peach orchards at the time of fruit formation (12- 15 males per trap per week) but we found very low populations of B. (B.) zonata in both methyl eugenol traps (4.6 males per trap per week) and fruit (zero infestation), whereas B. (B.) divenderi was caught in high numbers in both host and non-host locations in cue lure traps. After a random survey in 3 different orchards, two located at Nauni (Solan) and one at Rajgarh (Sirmaur), we found 56, 63 and 82 per cent infestation respectively. Similarly, 1 kg of nectarines purchased from 3 different local markets of Solan district, viz. Nauni, Ochhghat and Solan Mandi, produced 850, 670 and 160 gm of infested fruits respectively. All fruits were infested by B. (B.) divenderi with not a single fruit found infested with B. (B.) zonata . Earlier, B. (B.) divenderi had been recorded on nectarines during 2010 and misidentified as B. (B.) nigrofemoralis (Unpublished data, Dept. of Entomology, Dr. Y.P.U.H.F. Nauni, Solan).

Figures

FIGURE 1. Bactrocera (Bactrocera) divenderi Maneesh, Hancock and Prabhakar, sp. nov. (A–F), A: Head, B: Lateral thorax, C: Habitus, D: Abdomen, E: Thorax and F: wing

FIGURE 2. Bactrocera (Bactrocera) divenderi Maneesh, Hancock and Prabhakar, sp. nov. (A–E), A, B: Epandrium, C: Glans, D: Aculeus, E & F: Distal everslbte membrane

FIGURE 3. Bactrocera (Boctrocera) divenderi Maneesh, Hancock and Prabhakar, sp. nov. (A–J), A–H: Abdominal variations in paratypes, I: Female abdomen and J: Abdominal sternites