Bactrocera (Bactrocera) kohkongiae Leblanc

Leblanc, Luc, Jose, Michael San & Rubinoff, Daniel, 2015, Description of a new species and new country distribution records of Bactrocera (Diptera: Tephritidae: Dacinae) from Cambodia, Zootaxa 4012 (3), pp. 593-600 : 595-598

Bactrocera (Bactrocera) kohkongiae Leblanc new species

Description. Head ( Fig. 2 a). Vertical length 1.42±0.13 (SE) (1.12–1.63) mm. Frons, of even width, length 1.34±0.05 (1.26–1.47) times breadth; fulvous with fuscous around orbital setae and on anteromedial hump; latter covered by short red-brown hairs; orbital setae dark fuscous: 1 pair of superior orbitals, 2 pairs of inferior orbitals; lunule fuscous. Ocellar triangle black. Vertex fuscous. Face fulvous with medium-sized circular black spots in each antennal furrow; length 0.76±0.05 (0.67–0.90) mm. Genae fulvous, with fuscous subocular line or spot present; red-brown seta present. Occiput red-brown to fuscous, fulvous along eye margins and behind vertex; occipital row with 4–6 dark setae. Antennae with scape and pedicel fulvous, and flagellomere fulvous with pale fuscous on outer surface; a strong red-brown dorsal seta on pedicel; arista black (fulvous basally); length of segments: 0.21±0.03 (0.15–0.25) mm; 0.28±0.03 (0.22–0.33) mm; 0.67±0.07 (0.50–0.80) mm.

Thorax ( Fig. 2 b). Scutum colour variable, from red-brown with a variable dark fuscous to black lanceolate pattern to almost entirely dark fuscous with parallel red-brown markings at the level of notopleural suture ( Fig. 3a– e ). Pleural areas black except red-brown below postpronotal lobes and above mid coxae. Yellow markings as follows: postpronotal lobes; notopleura (notopleural callus); medium sized mesopleural (anepisternal) stripe, reaching midway between anterior margin of notopleura and anterior notopleural seta dorsally, continuing to katepisternum as a transverse spot, anterior margin straight or slightly convex; anatergite (posterior apex black); anterior 60% of katatergite (remainder black); two broad parallel-sided lateral postsutural vittae ending behind intra-alar setae. Postnotum black. Scutellum yellow except for narrow black basal band. Setae: 4 scapular, 2 anterior notopleural, 2 posterior notopleural, 2 mesopleural, 2 anterior supra-alar, 2 posterior supra-alar, 2 intraalar, 2 prescutellar, 2 scutellar; all setae well developed and red-brown.

Legs ( Fig. 2 d). Femora fulvous, except for small to large and elongate dark fuscous spot on outer apical surface of fore femur; fore tibia pale to dark fuscous, mid tibia basally slightly to extensively fuscous and apically fulvous, and hind tibia fuscous to dark fuscous; mid-tibiae each with an apical black spur; tarsi fulvous.

Wings ( Fig. 2 e). Length 5.94±0.32 (5.36–6.55) mm; cells basal costal and costal colourless; microtrichia in outer corner of cell costal only; remainder of wings colourless except fuscous subcostal cell, narrow fuscous costal band overlapping with R2+3 and widening slightly to extensively as it crosses extremity of R2+3 to end between extremities of R4+5 and M, a broad fuscous anal streak ending at apex of A1 + CuA2; dense aggregation of microtrichia around A1 + CuA2; supernumerary lobe of medium development.

Abdomen ( Fig. 2 c). Oval; terga free; pecten present on tergum III. Tergum I and sterna I and II wider than long. Tergum I dark fuscous. Tergum II orange-brown with transverse dark fuscous to black band across centre, which may or may not be extended to lateral margins, which are narrowly dark fuscous to black; terga III–V with a moderately broad medial band forming a “T-shaped” pattern with the broad transverse dark fuscous to black band across anterior margin of tergum III; terga III–V with usually broad, though occasionally narrow ( Fig. 3 f-j) diffuse dark fuscous markings on lateral margins. Shining spots on tergum V fuscous to dark fuscous. Posterior lobe of surstylus short. Sternum V with deep concavity along posterior margin. Abdominal sterna dark.

Diagnosis. This new species is a member of the B. dorsalis complex, which includes numerous cryptic species. It is similar and keys to, but does not exactly fit B. arecae (Hardy & Adachi) in the key published by Drew & Hancock (1994). In common with B. arecae , it has broad parallel-sided lateral postsutural vittae reaching intra-alar setae; the costal band is at least faintly overlapping R2+3 and slightly expanded across apex of R4+5; terga III–V have broad dark lateral margins in addition to the medial band; all femora are fulvous with a dark fuscous spot on outer apical surface of fore femora; and red-brown markings are present on the scutum. It differs from B. arecae in that B. kohkongiae is attracted to cue-lure, while B. arecae does not respond to male lures; the lateral markings on abdominal terga III–V are diffuse in B. kohkongiae and sharply defined in B. arecae ; and the red-brown markings on the scutum are frequently more extensive in B. kohkongiae than in B. arecae . Bactrocera kohkongiae also superficially resembles the sympatric B. dongnaiae Drew & Romig , but the costal band is markedly broader, almost confluent with R4+5, and the scutum is uniformly black in B. dongnaiae ; there are also significant genetic differences between these two species ( Leblanc et al. 2015a).

Material examined: 210 flies collected using cue-lure traps maintained for two days, in February 2011, in the Koh Kong Province, Cambodia ( Fig. 1 ). Eighteen sites were located in natural forest and 6 sites in agricultural or village environments. All but one specimen were collected in the forest sites. Measurements in description are based on the Holotype and 19 randomly selected specimens among the pinned paratypes.

Holotype: Male. Labelled: “ Cambodia: Krong Koh Kong, N 11° 35.561’ E 103° 20.414’, Road to Thma Bang, 9-11-ii-2011, M. San Jose & D. Rubinoff, FF036, Cue-lure trap.” Deposited in the University of Hawaii Insect Museum ( UHIM).

Paratypes: 87 males. Cambodia, Koh Kong Province, 9–11-ii-2011, at the following sites, identified by their geographical coordinates, along the road from Krong Koh Kong to Thma Bang ( Fig. 1 ): N 11.57145 E 103.101283 (3 pinned); N 11.582717 E 103.199083 (4 pinned, 2 vouchers: ms1136, 1137); N 11.591533 E 103.240217 (3 pinned); N 11.596017 E 103.282833 (4 pinned, 2 vouchers: ms1139, 1140); N 11.592683 E 103.340233 (11 pinned, 2 vouchers: ms1141, 1142); N 11.60825 E 103.363433 (5 pinned, 1 voucher: ms1333); N 11.609 E 103.363567 (3 vouchers: ms1149, 1150, 1151); N 11.609333 E 103.36425 (5 pinned, 3 vouchers: ms1146, 1147, 1148); N 11.609 E 103.364667 (2 pinned); N 11.6085 E 103.364967 (3 pinned); N 11.61005 E 103.365133 (3 pinned, 1 voucher: ms1143); N 11.611233 E 103.365383 (4 pinned, 1 voucher: ms1547); N 11.61238 E 103.365413 (12 pinned, 1 voucher: ms1785); N 11.60575 E 103.365983 (8 pinned, 5 vouchers: ms1306, 1307, 1780, 1781, 1783); N 11.661517 E 103.396983 (5 pinned, 1 voucher: ms1445); N 11.65905 E 103.4022 (1 pinned). 52 specimens, including the ethanol-preserved vouchers used for gene sequencing, deposited in the UHIM, 10 specimens in the Bishop Museum (Honolulu, Hawaii, USA), 10 in the Smithsonian Institute collection (Washington D.C., USA), and 15 specimens in the Queensland Department of Agriculture and Fisheries insect collection (Ecosciences Precinct, Brisbane, Australia). Other ethanol-preserved specimens not designated as paratypes are deposited in the UHIM.

Etymology. The name refers to the widespread occurrence of this species in the Cardamom Mountains area, in the Koh Kong Province of Cambodia.

Genetic sequencing. 22 specimens had their COI gene sequenced, and seven of these also had their EF1α and Period genes sequenced ( Table 1 ). Haplotype network for COI genes ( Fig. 4 ) indicates a high diversity within B. kohkongiae , with the majority of the haplotypes (89%) as singletons (haplotypes representing only as single specimen), indicative of a native population.

Figures

FIGURE 1. Map of trapping locations in Cambodia (February 2011), with number of specimens and vouchers of Bactrocera kohkongiae for each site or group of sites.

FIGURE 2. Bactrocera kohkongiae. A: head; B: head and scutum (Holotype); C: abdomen (Holotype); D: lateral view (Holotype); E: wing.

FIGURE 4. Statistical parsimony haplotype network based on COI (1464 bp) data for 21 specimens of B. kohkongiae. Circles represent the 20 unique haplotypes and their sizes are proportional to the number of specimens with those haplotypes. Black dots and bars represent missing intermediate haplotypes (mutational steps). Voucher numbers are indicated in each circle.

FIGURE 3. A – J: Variation in colour pattern of scutum (A – E) and abdomen (F to J) in Bactrocera kohkongiae. Molecular voucher codes are: A: ms 1149; B: ms 1144; C: ms 1151; D: ms 1140; E: ms 1150; F: ms 1149; G: ms 1145; H: ms 1146; I: ms 1139; J: ms 1137.