Esexalata Ponomarenko et M. Omelko, 2024

Ponomarenko, Margarita G. & Omelko, Ichail M., 2024, A new genus and two new species of gelechiid moths (Lepidoptera, Gelechiidae, Gelechiinae) from the East Malaysia with unusual male secondary characters, Zootaxa 5447 (4), pp. 573-582 : 574-575

Esexalata Ponomarenko et M. Omelko gen. n.

Type species: Esexalata beljaevi sp. n. by present designation.

Included species: E. beljaevi sp. n. and E. natalyae sp. n

Diagnosis. The new genus is similar to the genus Sabaha M. Omelko et N. Omelko, 2019 by general appearance, ciliate flagellum in males, semi-transparent area with piliform and forked scales on the hindwings; by male genitalia with hood-shaped uncus, well-developed culcitula of gnathos, fultura superior present, valva deeply divided into cucullus and sacculus, juxta consisting of two lobes integrated with vinculum ( Omelko & Omelko 2019b); by female genitalia with long ovipositor, elongated 8 th segment, 8 th sternite anteriorly covered by semi-sclerotised fold with honeycomb-like sculpture on inner surface ( Ponomarenko et al. 2023). The new genus differs from the related genus by forewings shimmer with metallic colours due to the optical interference and lacking semi-transparent area and by the presence of unique wing-like structures shimmer with the colours of the rainbow and long hair-pencils on the metascutum in males. Furthermore, the new genus differs from Sabaha by the male genitalia with the cucullus bearing setae on lateral side instead of medial side and presence of cornuti in the aedeagus and by female genitalia with the corpus bursae lacking signum. Whereas in the genus Sabaha the males without cornuti in the aedeagus, and females with signa in the corpus bursae.

Adult ( Figs 1–19 ). Head. Antenna in males with dorso-ventrally flattened scapus, a length of which 2 times longer than distance between eyes in front and its distal part more than 3 times wider than flagellomere in middle of flagellum ( Figs 3–4a ). It bears dense interrupted row of elongate scales on anterior edge, flagellum with long cilia on ventral side ( Figs 4–6 ). Basal segment of labial palpus one-third length of second; second segment with two dense rows of scales on ventral side, each row protruding at an angle; third segment with tuft of scales on dorsal side at middle or beyond.

Thorax. Forewing length 3.8–5.2 mm. Forewing dark brown with yellow spots and bands, differentiated into zones with ordinary scales and modified scales, shimmering with metallic green and pink colours due to optical interference in both sexes ( Figs 1, 2 , 10, 11 ). Hindwing with semi-transparent area covered by piliform and forked scales ( Figs 12, 13 ). Metathorax of males with two wing-like structures folded crosswise between wing bases, each wing-like structure located slightly medial-caudally compared to base of hindwing ( Figs 8 , 17 ). Each wing-like structure formed by elongated, fused in 2/3 distal part, flat and enlarged scales and remaining separate at hair-like base. A dense and long hair-pencil located under each wing-like structure arises from same base ( Figs 7, 9 ). Females have no such wing-like structures, but with bundles of elongate hair-like scales on metascutum. Forewing with Sc to costa at about middle of wing length; R 1 –R 5 to costa, R 1, R 2 and R 3 separate at base, R 4 and R 5 stalked basally, diverging before middle, stem R 4+5 and M 1 connate basally, M 1 –CuA 2 to termen, M 2 and M 3 stalked basally; CuA 1 and CuA 2 free basally; 1A and 2A merged distally. Hindwing with Sc to costa beyond 2/3 of wing length, Rs to costa before apex, Rs and M 1 shortly stalked basally, M 2 and M 3 separate, to termen; CuA 1 and CuA 2 free basally, CuA 1 to tornus and CuA 2 to dorsal margin ( Fig. 14 ).

Abdomen. First abdominal tergite in males with loop-shaped sclerotisation extending from base of tergite to approximately 3/5 of its length parallel with lateral sides, then curved at an angle before rounded convex distal part. Its surface with cellular sculpture ( Figs 15, 16, 19 ). Second abdominal sternite in both sexes with relatively long well-developed apodemes, venulae long, curved medially and semi-oval notch near anterior margin bounded by a fold on right side ( Figs 15, 19 , 36 ).

Male genitalia ( Figs 20–25, 27–29 , 31, 32 ). Uncus relatively small, hood-shaped. Gnathos with well-developed culcitula divided by longitudinal median constriction into two portions, and with small and flat median sclerite. Two longitudinal flat sclerites, termed “fultura superior” medially fused into a loop ( Fig. 32 ). Culcitula, lateral lobes of tegumen and fultura superior covered by small spines ( Fig. 31 ). Tegumen with lateral membranous areas that allow bending ventrally. Valva deeply divided into cucullus and sacculus. Cucullus with relatively long neck and enlarged basally and distally, its distal part bearing setae on lateral surface ( Fig. 25 ). Sacculus lamellar, narrowed beyond middle, with enlarged basal part and claw-like apex curved ventrally. Aedeagus tubular, more or less arcuately curved, with rounded flat apex, cornuti needle-shaped or filiform, without caecum, opening for ejaculatory ductus shifted on dorsal side and proximally bordered by a ribbon-like apodeme for phallic muscles; fixed at basal 1/3 by semi-sclerotised anellus. Juxta represented by two lateral lobes integrated with vinculum, near triangular in shape. Vinculum with wide triangular lateral parts and ventral excision, saccus wide and triangular.

Female genitalia ( Figs 33–35 ). Papillae anales oblong and relatively small. Ovipositor long, membrane between segment 8 and 9 more than 3 times longer than papillae anales (on the female of E. beljaevi only), 8th segment strongly elongated; sternite in proximal part covered by semi-sclerotised fold with honeycomb-like sculpture on inner surface. Vaginal part of ductus bursae widened, ductus bursae membranous, smoothly dilated towards corpus bursae; the latter membranous and lacking signum. Ductus seminalis arising beyond vaginal part of ductus bursae.

Distribution. Malaysia (Sabah).

Etymology. The genus name is composed of the Latin words “ sex ” and “ alata ” with the prefix “ e ” meaning “not six-winged”, generic name is feminine.

Figures

FIGURES 1–9. Esexalata gen. n., external morphology. 1, 3, 4a, 5–9—E. beljaevi sp. n.: 1—adult, holotype, male; 3—head, basal part of antenna and labial palpus, paratype, female; 4a—magnified scapus, pedicellus and base of flagellum, ventral view; 5—basal part of ciliate flagellum in male, dorsal view; 6—ditto, ventral view; 7—wing-like structure and hair-pencil in male, dorsal view, enlarged; 8—wing-like structures folded crosswise on the thorax in male; 9—hair-pencil under lifted wing-like structure in male; 2, 4—E. natalyae sp. n.: 2—adult, holotype, male; 4—ciliate antenna in male. Scale bar for figures 1, 2—1 mm; for figure 7—0.5 mm. pd—pedicellus, sc—scapus.

FIGURES 10–19. Esexalata gen. n., external morphology, wing venation and basal abdominal segments. 10–18—E. beljaevi sp. n.: 10—adult, view of wings with optical interference effect, paratype, female; 11—ditto, same specimen, photographed from a different angle; 12—hindwing with semi-transparent area covered by piliform and forked scales, paratype, female; 13—fragment of semi-transparent area on the hindwing with piliform and forked scales; 14—wing venation, paratype, female; 15—1st tergite with glandular area and 2nd sternite with semi-oval notch (shown by arrow), holotype, male; 16—fragment of glandular area on 1st tergite, enlarged; 17—position of wing-like structure on the thorax, paratype, male; 18—modeling with the application of wing-like structure and hair-pencil underneath on the base of the abdomen (1st tergite); 19—E. natalyae sp. n., 1st tergite (right) and 2nd sternite (left), paratype, male. Scale bar for figure 12—1 mm; for figures 15, 17, 19—0.5 mm.

FIGURES 31–36. E. beljaevi sp. n., genitalia and basal abdominal segments: 31—uncus, gnathos with culcitula and distal part of tegumen with spinose areas, lateral view, enlarged, holotype, GS 221 MP; 32—ditto, ventral view, enlarged, paratype, GS 223 MP; 33—female genitalia, ventral view, paratype, GS 227 MP; 34—ditto, 8th sternite and vaginal sinus, enlarged; 35—ditto, fragment of honeycomb-like sculpture on inner surface of semi-sclerotised fold; 36—1st tergite and 2nd sternite in female, GS 227 MP. Scale bar for figures 33 and 36—0.5 mm. cul—culcitula, d.pr—digitiform projection, f.s—fultura superior, hc.sc—honeycomb-like sculpture, l.gn—lateral sclerites of gnathos, l.teg—lateral lobes of tegumen with spines, m.ar—lateral membranous areas, m.gn—median sclerite of gnathos, s–scl.f—semi-sclerotised fold, sp.a—spinose areas, unc—uncus, v.sin— vaginal sinus, 8-st—8th sternite.

FIGURES 20–30. Esexalata gen. n., male genitalia and 8th abdominal segments. 20–26, E. beljaevi sp. n.: 20—unrolled, medial view, holotype, GS 221 MP; 21—aedeagus, lateral view, left side, holotype, GS 221 MP; 22—uncus, gnathos with culcitula, ventral view, paratype, GS 223 MP; 23—row of needle-shaped cornuti in aedeagus; 24—distal part of aedeagus, right side, paratype, GS 223 MP; 25—distal part of genitalia in glycerol; 26—sternite (left) and tergite (right) of 8th abdominal segment, paratype, male; 27–30, E. natalyae sp. n.: 27—unrolled, medial view, holotype, GS 229 MP; 28—aedeagus, lateral view, left side, holotype, GS 229 MP; 29—distal part of aedeagus with bundle of long filiform cornuti; 30—sternite (left) and tergite (right) of 8th abdominal segment, paratype, male. Scale bar 0.2 mm with the exception of enlarged figures 22, 23 and 29. set. lat—setae on the lateral side of cucullus.