Anarsia isogona Meyrick, 1913

Koo, Jun-Mo, Na, Jin-Ho, Paek, Munki & Cho, Soowon, 2023, First report of the genus Semioscopis Hübner and four species of Gelechioidea (Lepidoptera) from Korea with redescriptions, Zootaxa 5325 (4), pp. 509-528 : 517-521

Anarsia isogona Meyrick, 1913

(Korean name: sam-gag-mu-neui-teol-su-yeom-ppul-na-bang)

( Figs 5 , 6 )

Anarsia isogona Meyrick, 1913: 169 . Type locality: Nilgiris , India.

Anarsia isogona ; Meyrick 1925: 153; Meyrick 1935: 69; Gaede 1937: 402; Clarke 1969: 245; Park 1995: 60; Ueda 1997: 79; Hua 2005: 4; Heppner 2012: 6; Sakamaki 2013b: 306; Bae et al. 2016: 230 ; Park & Bae 2018: 277 .

Anarsia protensa Park 1995: 60 , Fig. 15, partim (misidentified only for female).

Ananarsia isogona ; Ponomarenko 1997: 52; Ponomarenko 2009: 341.

Anarsia isogorca [sic, recte isogona ]; Li & Zheng 1997: 121.

Anarsia isogama [sic, recte isogona ]; Shamsudeen 2013: 75; Shamsudeen 2018: 954.

Material examined. 2♁, 4♀, Korea, Deokchon-ri, Samsan-myeon , Yeosu-si, JN [Jeollanam-do], N34° 01′ 14.39″, E127° 18′ 13.05″, Alt. 25 m, 28.vii.2022, coll. E.J. Lim, gen. slide nos. NJH0060 (♁), -0061 (♀), -0062 (♀), - 0063 (♀), -0084 (♁), KJM0340 (♀), wings slide nos. NJH0079 (♀), -0080 (♀), -0081 & -0082 (right and left wings, respectively, from the same ♁ specimen), -0083 (♁), COI barcode CBNU672–677 (GenBank accession nos. OQ573704–OQ573709), specimen accession nos. CBNUPM000030–000035 .

Diagnosis. The species is externally similar to A. protensa , A. paraisogona Park & Ponomarenko, 1996 and A. incerta Ueda, 1997 (most similar to the last of the three species) in that there is a large subtriangular patch on medial costa of their forewing, but it is clearly distinguishable by the following characteristics: 1) in the male of A. Isogona , scale pencils on the undersurface of forewing and on the mesothoracic anepisternum are absent, while in A. protensa (see Ueda 1997: 86) the latter is present only, and in A. paraisogona (see Bae et al. 2016: 228), the former is present only; 2) in the male sternite VIII of A. Isogona , it has a concavity at mesoanterior margin and a rounded posterior margin, while in A. protensa (see Ueda 1997: Fig. 22A) it has a concavity at mesoposterior margin, and in A. incerta (see Ueda 1997: Fig. 18A), it has a relatively less concave mesoanterior margin; 3) in the male genitalia of A. isogona , they have valvae that are rapidly narrowed apically beyond a convexity, left valva with a long and slender ventro-basal process, and right valva with a slender and weak process (see an arrow in Fig. 6F ; see also Bae et al. (2016: Fig. 42)) and a short basal process, while in A. protensa (see Ueda 1997: Fig. 22C) they have valvae that have a broad apex, and left and right valvae without the processes, in A. paraisogona (see Park & Ponomarenko 1996: Fig. 33; Bae et al. 2016: Figs 43, 43a) they have a broad left valva with a basocostal process, and entirely slender right valva with a free ventral process, and in A. incerta (see Ueda 1997: Fig. 18C) they have valvae which are broad and have rounded apex; 4) in the female genitalia of A. isogona , they have trapezoidal tergite VIII, a pouch of sterigma, the same sized corpus bursae with the pouch of sterigma, and no signum, while in A. protensa (see Ueda 1997: Fig. 22D) and A. paraisogona (see Park & Ponomarenko 1996: Fig. 62) they have not the pouch of sterigma, clearly longer and larger ductus and corpus bursae, and signum present, and in A. incerta (see Ueda 1997: Fig. 18D) they have tergite VIII which is produced anteriorly into a trapezoidal plate at middle, and signum present.

Redescription. Adults of both sexes ( Fig. 5 ), forewing length 4.0– 5.5 mm (wingspan 9.0– 12.5 mm) (n=6) ( Bae et al. 2016: wingspan 10.5–11.0 mm; Sakamaki 2013b: wingspan 9.0–12.0 mm; Ueda 1997: male forewing length 4.2–5.6 mm, female forewing length 4.5–5.7 mm).

Head: Vertex covered with brownish-gray scales; distal end of each scale whitish-gray. Postocular scales dark brownish-gray. Antenna about 0.7–0.8× shorter than length of forewing; scape brownish-gray; pedicel+flagellum alternately ringed with brownish-gray and grayish-brown. Second palpomere of male labial palpus ( Figs 5D, E ) triangular, clothed with rough scales, outer surface dark brownish-gray with distal 1/7 whitish-gray, inner surface whitish-gray with ventral margin dark brownish-gray; third palpomere absent. Second palpomere of female labial palpus ( Figs 5F, G ) triangular, outer surface dark brownish-gray with distal 1/4 whitish-gray, inner surface whitish-gray with ventral half dark brownish-gray, about 0.8× shorter than length of third palpomere; the latter whitish-gray with dark brownish-gray rings.

Thorax: Notum brownish-gray speckled with whitish-gray. Tegula same as notum, with blackish extreme base. Forewing brownish-gray speckled with whitish-gray, irregularly suffused with grayish-brown; small blackish costal streak situated at base; two blackish costal marks around basal 1/5 (one right before basal 1/5 and other right after basal 1/5 of costa); large blackish costal patch subtriangular, situated at middle; two blackish costal marks beyond subtriangular medial patch (one right before distal 3/10 and other right after distal 3/10); a longitudinal blackish linear mark at basal 1/10 of subcosta (situated between basal part of Sc and Rs veins); two indistinct grayish-brown blotches at distal 3/10 and 1/5; grayish-brown blotch right before basal 1/10 of inner margin; obscure blackish dots along distal 1/5 of costa and along termen; fringe grayish-brown, mixed with dark grayish-brown and orangish-gray; pterostigma well-developed; venation ( Figs 5J, L ) with R 1 arising beyond basal half of discal cell; Sc and R 1 invisible from subcosta to costa; distance between origins of R 1 and R 2 about 2.4× longer than that of R 2 and R 3; R 4 and R 5 stalked at basal 1/3–1/2; R 4+5 and M 1 unstalked or stalked at base; origins of M 2 and M 3 close; CuA 1 and CuA 2 free; 1A+2A forked at about basal 3/10; discal cell weakly closed. Hindwing hyaline in about basal 1/3, then covered with orangish-gray scales, gradually darker distally; veins covered with brown scales; fringe grayish-brown; basal half of costa convex; frenulum with acanthi fused distally into a single acanthus in male ( Fig. 5K ), three frenula in female ( Fig. 5M ); venation ( Figs 5J, L ) with R 1 running into Sc from about basal 3/10 of discal cell (see arrows in Figs 5J, L ); Rs preapical; Rs and M 1 stalked at about basal 1/5; distance between origins of Rs+M 1 and M 2 about 2× longer than that of M 2 and M 3; M 3, CuA 1 and CuA 2 free; discal cell closed. Hindtibia ( Figs 5H, I ) orangish-gray with brown ventral half on outer surface, orangish-gray on inner surface; bristles orangish-gray; two pairs of spurs, one pair at middle, other pair at distal end. Hindtarsus ( Figs 5H, I ) orangish-gray with brown scales.

Abdomen: Abdomen brownish-gray, mixed with whitish-gray; anal tuft brownish-orange in male, relatively shorter grayish-brown tuft in female. In male ( Fig. 6J ; see also Bae et al. (2016: Fig. 42a)), anterior margin of sternites VII–VIII slightly concave medially; sternite VIII tongue-shaped, with long lateral scale pencils. In female ( Fig. 6K ), tergite VII gradually narrowed anteriorly, posterior margin concave.

Male genitalia ( Figs 6A–G ): See also Ueda (1997: Figs 17A–C); Bae et al. (2016: Figs 42, 42b). Uncus digitate, slightly downturned, gradually broadened basally, with setae on inner surface. Socius produced into ovaloid shape, bearing rather long setae on outer surface; length about 2.0× longer than length of uncus. Tegumen elongated, nearly same length as valva, narrowed beyond basal 1/2–1/3, slightly expanded laterally before being narrowed; basolateral ovaloid expansion well-developed. Valvae asymmetrical, with numerous palmately modified scales in distal half; left valva broadened ventro-medially with a pouch-like complex fold, then rapidly tapered apically; a ventro-basal process of left valva well-sclerotized, slender, entirely curved upward, with widened base and sharply pointed tip; right valva gently convex ventrally in basal 2/3, then rapidly narrower apically, with a slender and weak process (arising from basal 3/10–1/5 of ventral margin (see an arrow in Fig. 6F ; see also Bae et al. (2016: Fig. 42))) and a small and free sclerotized basal process. Vinculum narrow. Juxta with sclerotized medial ridge vertically and two setose ovaloid lobes (one on each side). Phallus slender, downturned in basal 3/5, then slightly upturned with sharp tip, about 0.6× shorter than length of valva; coecum thorn-shaped, curved posteriorly at base.

Female genitalia ( Figs 6H, I ): See also Ueda (1997: Fig. 17D). Papillae analis broad, trapezoidal with numerous setae. Apophyses posteriores about 3× longer than length of apophyses anteriores. Tergite VIII depressed trapezoidal; a small ventral triangular sclerite situated at near medial anterior margin. Sterigma produced anteriorly into triangular shape at middle of anterior margin, then connected with membranous funnel-like tube followed by a large ovoidal pouch. Ostium bursae situated beyond middle; lamella postvaginalis semicircular arch-shaped; lamella antevaginalis semicircular to trapezoidal. Antrum funnel shaped, as long as ductus bursae. Ductus bursae wrinkled; ductus seminalis arising from anterior end. Corpus bursae ovoidal, same sized with pouch of sterigma; signum absent.

Host plants. Schima Reinw. ex Blume (Theaceae) ( Sakamaki 2013b).

Distribution. India, China, Taiwan, Japan, Laos, Vietnam, Sri Lanka ( Ponomarenko 1997; Ueda 1997; Hua 2005; Sakamaki 2013b; Shamsudeen 2013; Bae et al. 2016; Park & Bae 2018), Korea (new record).

Figures

FIGURE 5. Anarsia isogona. A, B, male (CBNUPM000034, 000030); C, female (CBNUPM000035); D, outer view of male labial palpus; E, inner view of male labial palpus; F, outer view of female labial palpus; G, inner view of female labial palpus; H, outer view of hindleg; I, inner view of hindleg; J, male venation, wings slide no. NJH0082 (with an arrow pointing to R1 running into Sc); K, close-up of frenulum; L, female venation, wings slide no. NJH0080 (with an arrow pointing to R1 running into Sc); M, close-up of frenula.

FIGURE 6. Genitalia and abdomen of Anarsia isogona. A, male genitalia, gen. slide no. NJH0060; B, phallus; C, close-up of uncus+socius, gen. slide no. NJH0084; D, close-up of vinculum+juxta; E, close-up of left valva; F, close-up of right valva (with an arrow pointing to a weak process); G, close-up of modified scales of valva; H, female genitalia, gen. slide no. KJM0340; I, close-up of ostium bursae+antrum; J, male abdomen (terga left, sterna right, gen. slide no. NJH0060); K, female abdomen (terga left, sterna right, gen. slide no. KJM0340).