Toleria vietnamica, Gorbunov & Arita, 2020

Gorbunov, Oleg G. & Arita, Yutaka, 2020, A new species of the genus Toleria Walker, 1865 [“ 1864 ”] from Vietnam, with a catalogue of Asian Cissuvorini (Lepidoptera: Sesiidae), Zootaxa 4802 (2), pp. 349-360 : 350-353

Toleria vietnamica sp. nov.

( Figs 1–3 )

Holotype ♀ ( Figs 1–3 ) with labels: “ Bac Kan / Ba Be, Ban Vai , / 1.V.2006 / R. Matsumoto ”; “Yutaka Arita / Collec- tion, NSMT / Donation, 2009 / Ħm DZOi± dzDz ”; “ SESIIDAE / Pictures №№ / 0159-0160–2018 / Photo by O. Gorbunov ”; “Genitalia examined / by O. Gorbunov / Preparation № / OG–027-2018”; “ HOLOTYPUS ♀ / Toleria vietnamica / O. Gorbunov et Arita, 2020 / O. Gorbunov des., 2018” ( NSMT).

Description. Female (holotype) ( Figs 1, 2 ). Alar expanse 31.0 mm; body length 15.1 mm; forewing 13.8 mm; antenna 6.2 mm.

Head with antenna brown with a dense admixture of light brown scales dorsally on basal half; scapus yellow to pale yellow; frons gray with purple sheen and a very narrow pale yellow lateral margin; vertex and labial palpus entirely yellow to dark yellow; occipital fringe white dorsally and yellow laterally.

Thorax with patagia dark yellow to yellow-orange and with an admixture of dark brown scales with greenishpurple sheen dorsally; tegula dark brown with bronze-purple sheen, densely covered with light brown scales mask- ing background colouration and with a large yellow-orange spot at base of forewing; mesothorax dark brown with bronze-purple sheen and a dense admixture of dark yellow to yellow-orange scales posteriorly; metathorax dark brown with bronze-purple sheen, densely covered with chestnut-brown elongate scales; thorax laterally dark gray

with purple-violet sheen and an admixture of dark yellow and light brown scales anteriorly; posteriorly both met-

epimeron and metameron dark gray-brown with purple-violet sheen, covered with long light brown hairs. Legs with

neck plate light brown; fore coxa dark yellow to yellow-orange with a small dark gray spot with bronze sheen dis-

tally; fore femur dark yellow to yellow-orange; both fore tibia and fore tarsus light brown dorsally and dark yellow

ventrally; mid coxa dark gray with bronze sheen and a few light brown scales internally; mid femur externally dark

yellow to yellow-orange and with a small black spot with bronze sheen distally and with a raw of light brown hairs

at posterior margin, internally dark yellow; mid tibia light brown with an admixture of dark yellow scales medio-

internally; spurs dark yellow; mid tarsus dark yellow, basal tarsomere dorsally light brown; hind coxa mixed with

dark gray, dark yellow and light brown scales; hind femur externally dark yellow to yellow-orange and with a small

black spot with bronze sheen distally and with a raw of light brown hairs at posterior margin, internally dark yellow;

hind tibia light brown, but slightly darker exterior-basally and somewhat lighter internally; spurs dark yellow; hind

tarsus light brown dorsally and dark yellow internally. Forewing dorsally with basal part black with dark blue sheen;

costal margin dark brown to black with dark blue sheen and a dense admixture of chestnut brown scales basally;

CuA-stem, anal margin and veins distally of discal spot dark brown to black with dark blue sheen; discal spot nar-

row, S-shaped, black with dark blue-violet sheen; transparent areas well-developed; apical area undeveloped, but

surface of cells between veins R 3 –CuA 1 divided by an extremely narrow scaled line to middle from termen to discal spot; cilia dark gray-brown with bronze sheen; ventrally veins and discal spot dark brown with bronze sheen and

a dense admixture of dark yellow scales on costal and anal margin and CuA-stem basally. Hindwing transparent;

dorsally veins veins, discal spot, outer margin and cilia dark brown to black with bronze sheen; discal spot narrow,

triangular, reaching to vein M 2; outer margin extremely narrow, about 0.2 times as broad as cilia; ventrally veins dark brown with bronze sheen and an admixture of dark yellow scales on CuA-stem and veins CuA 1 and CuA 2.

Abdomen black with dark blue sheen; dorsally tergites 1 and 2 each densely covered with chestnut-brown elon-

gate scales; tergite 1 with a large dark yellow to yellow-orange spot lateral-distally; tergite 2 with a narrow dark yel-

low to yellow-orange stripe distally; ventrally sternites 1+2 and 3 each with a broad dark yellow to yellow-orange

stripe distally; anal tuft small dark gray with bronze sheen.

Female genitalia (holotype) (Genital preparation № OG–027-2018) ( Fig. 3 ). Papillae anales well-sclerotized with rounded membranous areas at base of setae, covered with long and short setae; tergite 8 relatively broad, cov- ered with sparse short setae; posterior apophysis slightly longer than anterior apophysis; lamella postvaginalis pres- ent, H-shaped, with narrow, pointed “wings”; lamella antevaginalis absent; ostium bursae opening near posterior margin of sternite 7, relatively broad, membranous, tube-shaped; antrum short, with a narrow well-sclerotized semi- circle posteriorly and with a narrow well-sclerotized plate at base of ductus seminalis; ductus bursae long, relatively thin, membranous; corpus bursae large, ovoid, membranous, with numerous transverse folds; signum present, oval, with a short fold, consists of many well-sclerotized, small teeth.

Male. Unknown.

Individual variability. Unknown.

Differential diagnosis. Superficially this new species seems to be the closest to Toleria colochelyna ( Bryk, 1947) , but it can be distinguished by the colouration of the scapus (scapus yellow dorsally and light brown ventrally in T. colochelyna , vs. scapus entirely yellow to pale yellow in T. vietnamica sp. nov.), occipital fringe (entirely yellow in T. colochelyna , vs. white dorsally and yellow laterally T. vietnamica sp. nov.), tegula (brown to dark brown in the species compared, vs. tegula dark brown densely covered with light brown scales masking background coloura- tion and with a large yellow-orange spot at base of forewing in T. vietnamica sp. nov.), thorax laterally (grey-brown with bronze sheen in T. colochelyna , vs. dark gray with purple-violet sheen and an admixture of dark yellow and light brown scales anteriorly in T. vietnamica sp. nov.), fore tibia (entirely yellow-orange in the species compared, vs. light brown dorsally and dark yellow ventrally in T. vietnamica sp. nov.), hind tibia (externally orange with a small brown spot basally and yellow internally in T. colochelyna , vs. light brown, but slightly darker exterior-basally and somewhat lighter internally in T. vietnamica sp. nov.), and abdomen (dorsally tergites 1–4 each with a narrow yellow stripe posteriorly; tergite 1 with a large yellow spot laterally; tergites 2–3 each with admixture of yellow, orange and light brown scales medially; tergites 4–7 each densely covered with yellow and dirty orange scales, masking background coloration; ventrally sternites 1+2–4 each dark brown anteriorly and yellow to yellow-orange posteriorly; remaining sternites yellow-orange to light brown; anal tuft yellow-orange to orange in the species compared, vs. dorsally tergites 1 and 2 each densely covered with chestnut-brown elongate scales; tergite 1 with a large dark yellow to yellow-orange spot lateral-distally; tergite 2 with a narrow dark yellow to yellow-orange stripe distally; ventrally sternites 1+2 and 3 each with a broad dark yellow to yellow-orange stripe distally; anal tuft dark gray with bronze sheen in T. vietnamica sp. nov.). In addition, these two species have differences in the structure of the female genitalia: papillae anales visibly broader and posterior apophysis relatively shorter in T. vietnamica sp. nov.; tergite 8 and lamella postvaginalis more narrow in the new species; signum relatively larger, but with more short fold medially in T. vietnamica sp. nov. (compare Figs 3 and 4 with fig. 38 in Gorbunov & Arita 2001: 40).

From T aegerides ( Strand, 1916) , this new species clearly differs by the colouration of the antenna (antenna yellow-orange dorsally and light brown ventrally in T. aegerides vs. antenna brown with a dense admixture of light brown scales dorsally on basal half in T. vietnamica sp. nov.), tegula (anteriorly dark brown with bronze sheen and an admixture of individual light brown scales, posteriorly pale yellow to yellow in the species compared vs. tegula dark brown with bronze-purple sheen, densely covered with light brown scales masking background colouration and with a large yellow-orange spot at base of forewing in T. vietnamica sp. nov.), and abdomen (dorsally dark brown with bronze sheen and an admixture of individual light brown scales; tergite 1 with a narrow yellow stripe distally; tergites 3 and 4 each densely mixed with yellow scales; tergites 5 and 6 each mixed with yellow scales medio-distally; anal tuft light brown-yellow medially and yellow laterally in T. aegerides vs. black with dark blue sheen; dorsally tergites 1 and 2 each densely covered with chestnut-brown elongate scales; tergite 1 with a large dark yellow to yellow-orange spot lateral-distally; tergite 2 with a narrow dark yellow to yellow-orange stripe distally; anal tuft dark gray with bronze sheen in T. vietnamica sp. nov.). Besides this, these species can be distinguished by the shape of the corpus bursae and signum of the female genitalia (compere Fig. 3 with fig. 18 in Arita & Gorbunov 1998: 161).

From T. sinensis (Walker, 1865 [“1864”], T. vietnamica sp. nov. is clearly separable by the coloration of the abdomen (dorsally tergites 4–6 each yellow with a narrow black stripe anteriorly in T. sinensis , vs. dorsally tergites 1 and 2 each densely covered with chestnut-brown elongate scales; tergite 1 with a large dark yellow to yellow-orange spot lateral-distally; tergite 2 with a narrow dark yellow to yellow-orange stripe distally in T. vietnamica sp. nov.).

Bionomics. The larval host plant of this new species is unknown. The holotype was collected in the beginning of May.

Habitat. Unknown.

Distribution. Known from Ba Bể National Park, Bẳc Kan Province in North Vietnam only.

Etymology. This new species is named after Vietnam, the terra typica.

Figures

FIGURE 3. Female genitalia of Toleria vietnamica sp. nov. Genital preparation № OG–027-2018. Scale bar: 2.0 mm.

FIGURES 1–2. Female (holotype) of Toleria vietnamica sp. nov. 1) upside. Sesiidae picture № 0159–2018. Alar expanse 29.0 mm; 2) ditto, underside. Sesiidae picture № 0160–2018.