Bactrocera (Bactrocera) vargasi Leblanc & Doorenweerd, 2021

Leblanc, Luc, Tsatsia, Francis & Doorenweerd, Camiel, 2021, Novel lures and COI sequences reveal cryptic new species of Bactrocera fruit flies in the Solomon Islands (Diptera, Tephritidae, Dacini), ZooKeys 1057, pp. 49-103 : 49

Bactrocera (Bactrocera) vargasi Leblanc & Doorenweerd sp. nov.

Fig. 16A-F

Type material.

Holotype. Solomon Islands • ♂; Kolombangara, forest; -8.0563, 157.1320; 232 m; 9-13 Apr. 2018; L. Leblanc, F. Tsatsia leg.; zingerone baited trap FFSo046. Deposited in UHIM. Paratypes. 42 males. Solomon Islands • 2 ♂; Guadalcanal, forest; 4-16-iv-2018; L. Leblanc, F. Tsatsia leg.; -9.4041, 159.8628; 153 m; zingerone trap FFSo011 • 2 ♂; same locality and date as for preceding; -9.4045, 159.8644; 142 m; trap FFSo012 • 2 ♂; same locality and date as for preceding; -9.4048, 159.8645; 144 m; trap FFSo013 • 2 ♂; same locality and date as for preceding; -9.4064, 159.8644; 167 m; trap FFSo14 • 3 ♂; same locality and date as for preceding; -9.4067, 159.8647; 167 m; trap FFSo015; molecular vouchers UHIM.ms08665, UHIM.ms08666, UHIM.ms08667 • 2 ♂; same locality and date as for preceding; -9.4069, 159.8664; 153 m; trap FFSo017 • 4 ♂; same locality and date as for preceding; -9.4064, 159.8671; 145 m; trap FFSo018 • 2 ♂; same locality and date as for preceding; -9.4059, 159.8672; 133 m; trap FFSo019 • 2 ♂; same locality and date as for preceding; -9.4055, 159.8665; 145 m; trap FFSo020 • 1 ♂; same locality and date as for preceding; -9.4053, 159.8664; 139 m; trap FFSo021 • 3 ♂; same locality and date as for preceding; -9.4040, 159.8652; 125 m; trap FFSo023 • 3 ♂; same locality and date as for preceding; -9.4038, 159.8646; 103 m; trap FFSo024 • 1 ♂; same locality and date as for preceding; -9.4039, 159.8673; 103 m; trap FFSo025 • 2 ♂; same locality and date as for preceding; -9.4035, 159.8681; 85 m; trap FFSo026 • 2 ♂; same locality and date as for preceding; -9.4026, 159.8695; 57 m; trap FFSo027 • 1 ♂; same locality and date as for preceding; -9.400, 159.8700; 50 m; trap FFSo029 • 2 ♂; Kolombangara, forest; -8.0563, 157.1320; 232 m; 9-13 Apr. 2018; L. Leblanc, F. Tsatsia leg.; zingerone baited trap FFSo046 • 2 ♂; same locality and date as for preceding; -8.0479, 157.1262; 267 m; trap FFSo048 • 1 ♂; same locality and date as for preceding; -8.0306, 157.1168; 389 m; trap FFSo054 • 1 ♂; same locality and date as for preceding; -8.0252, 157.1159; 455 m; trap FFSo059 • 1 ♂; same locality and date as for preceding; -8.0328, 157.1164; 356 m; trap FFSo075 • 1 ♂; same locality and date as for preceding; -8.0395, 157.1237; 308 m; trap FFSo079. 29 of the paratypes are deposited at UHIM, seven at WFBM, four at USNM, and two at BSI.

Differential diagnosis.

The overall appearance and specifically the wing of B. vargasi (Fig. 16E ) is very similar to that of B. frauenfeldi (Schiner) (Fig. 17 ) [Solomon Island populations], B. trilineola Drew and B. parafrauenfeldi Drew [all three are members of the morphological B. frauenfeldi complex], but B. vargasi differs from B. trilineola and B. parafrauenfeldi in having a nearly entirely black abdomen (Fig. 16 ), and can be separated from B. frauenfeldi in lacking lateral postsutural yellow vitta.

Molecular diagnosis.

We sequenced three specimens which have COI sequences closest to B. quasiinfulata Drew & Romig at 7.24% minimum pairwise distance. The maximum intraspecific distance is 1.2%. Sequences of the morphologically similar B. frauenfeldi and B. trilineola were also included in the reference dataset but are highly dissimilar to B. vargasi with>8% pairwise distance. Bactrocera parafrauenfeldi was not included in the reference set but is presumed to be closely related to B. trilineola ( Drew 1989).

Description of adult.

Male. Head (Fig. 16A ). Height 1.61 ± 0.22 (SD) (1.33-1.93) mm. Frons, of even width, 0.83 ± 0.08 (0.67-0.93) mm long and 1.63 ± 0.11 (1.43-1.85) times as long as broad; fulvous and narrowly yellow along eye margin; anteromedial hump covered by short red-brown microtrichia; three pairs of black frontal setae present; lunule yellow. Ocellar triangle black. Vertex black with yellow spot behind ocellar triangle and two pairs of black vertical setae. Face fulvous with a pair of very large circular black spots in antennal furrows; length 0.51 ± 0.06 (0.43-0.63) mm. Gena fulvous, with small dark fuscous subocular spot and a red-brown seta. Occiput black and narrowly fulvous along eye margin; a row of 6-9 black postocular setae present behind eye. Antenna with scape and pedicel fulvous and flagellum dark fuscous tending dark fulvous on inner surface; a strong red-brown dorsal seta on pedicel; arista fulvous basally and black distally; length of segments: 0.31 ± 0.03 (0.27-0.33) mm; 0.36 ± 0.03 (0.33-0.40) mm; 0.88 ± 0.09 (0.73-1.00) mm.

Thorax (Fig. 16B ). Scutum entirely black with dense silvery microtrichia on all scutum except two broad parallel longitudinal shining black areas interrupted at level of notopleural suture. Pleural areas black. Yellow markings: posterior half of postpronotal lobe (anteriorly fuscous); notopleuron; moderately broad anepisternal stripe with anterior margin convex, reaching to mid distance between anterior and posterior notopleural setae dorsally; a very small transverse spot on katepisternum below the anepisternal stripe; anterior 3⁄5 of anatergite and katatergite (posteriorly black). Mediotergite black. Scutellum broadly black medially and yellow laterally. Setae: 1 pair scutellar; 1 pair prescutellar acrostichal; 1 pair intra-alar; 1 pair postalar; 1 pair postsutural supra-alar; 1 pair anepisternal; 2 pairs notopleural; 2 pairs scapular; all setae well developed and black.

Legs (Fig. 16F ). Legs black with yellow fore femur, basal 2⁄5 of mid and hind femur, and mid and hind tarsi. Fore femur with a row of long pale dorsal setae. Mid-tibia with an apical black spur.

Wing (Fig. 16E ). Length 6.2 ± 0.6 (5.3-6.9) mm; basal costal and costal cells dark fuscous with microtrichia covering both cells; faint narrow fuscous costal band confluent with R2+3, remaining narrow to end shortly past the apex of R2+3; dark fuscous straight band across r-m and dm-cu veins and reaching wing margin; broad dark fuscous anal streak; remainder of wing hyaline; dense aggregation of microtrichia around A1 + CuA2; supernumerary lobe weakly developed.

Abdomen (Fig. 16C ). Oval with tergites not fused; pecten present on tergite III; posterior lobe of surstylus short; abdominal sternum V with a deep concavity on posterior margin. Base of syntergite I+II wider than long. Tergites entirely black with yellow lateral bands along posterior margin of tergite II. Ceromata on tergite V black. Abdominal sternites black.

Female. Unknown.

Etymology.

We proudly name this species to honor the famous fruit fly ecologist Roger I. Vargas (1947-2018) ( Stark et al. 2018). The species name Bactrocera vargasi is a noun in genitive case. Roger and LL collaborated extensively on projects during years spent in the South Pacific Islands. Roger brought LL to Hawaii in 2003 to continue working on fruit flies, and he secured funding and provided guidance that allowed LL to obtain a PhD title in 2010.

Male attractant.

Zingerone.

Notes.

Bactrocera vargasi was included as B. spnSol07 in Doorenweerd et al. (2020).

Figures

Figure 16. Bactrocera vargasi sp. nov. A head B head and scutum C abdomen D male genitalia E wing F lateral view.

Figure 17. Bactrocera frauenfeldi (Schiner) A head B head and scutum C abdomen, male D wing E lateral view, female.