Six new species forming the Sumbana species group in genus Nemophora Hoffmannsegg 1798 from Indonesia

NEWS - Sumbawa longhorn (Nemophora sumbana Kozlov, sp. nov.), Timor longhorn (Nemophora timorella Kozlov, sp. nov.), shining shade longhorn (Nemophora umbronitidella Kozlov, sp. nov.), Wegner longhorn (Nemophora wegneri Kozlov, sp. nov.), long brush longhorn (Nemophora longipeniculella Kozlov, sp. nov.), and short brush longhorn (Nemophora brevipeniculella Kozlov, sp. nov.) from the Lesser Sunda Islands in Indonesia.

The Lesser Sunda Islands consist of two parallel, linear oceanic island chains, including Bali, Lombok, Sumbawa, Flores, Sumba, Sawu, Timor, Alor, and Tanimbar. The oldest of these islands have been continuously occurring for 10–12 million years. This long period of isolation has allowed significant in situ diversification, making the Lesser Sundas home to many endemic species.

This island chain may act as a two-way filter for organisms migrating between the world's two great biogeographic regions, Asia and Australia-Papua. The recognition of a striking clinal mixture of species from different biogeographic regions was a key insight leading to the identification of the Wallace Line and, ultimately, to the creation of the field of biogeography.

Southeast Asia has an extraordinary diversity of fairy moths, with many species of the genus Nemophora Hoffmannsegg 1798 recently described from various parts of the region. However, the fairy moth fauna known from the Lesser Sundas was previously limited to a single species, Nemophora punctifasciella Kozlov 2024.

N. sumbana differs from other species in the sumbana group by its large size, strongly oblique outer margin of the basal plane of the forewing (reaching the costa at 0.4 and the dorsum at 0.2 × FWL), a spot on the outer wing margin that does not reach the apex of the forewing, and relatively short labial palpi (0.3‒0.4 × vertical eye diameter). The male is very similar to N. umbronitidella, differing in the smaller medial process of the transtilla, the shape of the anellus, and the relatively thick and straight phallic tip.

N. timorella is most similar to N. umbronitidella, differing in the smaller size (FWL 4.3‒5.0 mm), pale yellowish brown basal plane of the forewing, an outer margin of the basal plane that is nearly perpendicular to the wing margin, a longer vinculum, the tips of the valves extending slightly beyond the tip of the tegument, a medial notch on the fused bases of the valves, and the triangular shape of the arrowheads on the juxta. Distinguishes from N. longipeniculella and N. brevipeniculella by the presence of two brilliantly iridescent longitudinal silver lines on the dark ochre brown basal plane of the forewings.

N. umbronitidella most closely resembles N. timorella, which distinguishes it by its larger size (FWL 5.2–5.7 mm), oblique outer margin of the forewing basal plane, shorter vinculum, tegument tip extending slightly beyond the valve tip, medial protuberances on the fused valve bases, and anchor-shaped juxta. Distinguishes from N. longipeniculella and N. brevipeniculella by the presence of two brilliantly iridescent longitudinal silver lines on the dark ochre brown basal plane of the forewings.

N. wegneri most closely resembles N. umbronitidella, which differs by the bright yellow posterior margin of the dark brown metathorax (male only), shorter male antennae, dark brown scape, and long phallus (1.1 x vinculum length) with prominent ventral lobe near apex.

N. longipeniculella most closely resembles N. brevipeniculella, which differs by the female's longer antennae (almost as long as the forewing) that are thickened with dark brown scales, ochre yellow scales covering a bronze band adjacent to the forewing base, ochre scales at the forewing apex, and an unusually long epiphysis that is articulated at 0.25 of the total length of the tibia and reaches its apex. It differs from the female N. umbronitidella in having a yellow forewing base.

N. brevipeniculella most closely resembles N. longipeniculella, which distinguishes it by the shorter (0.8 × forewing length) antennae of the female that are thickened with dark brown scales, dark brown scales covering the bronze band adjacent to the forewing base, brown scales at the forewing apex, and the distinctive size of the epiphysis, which is articulated at 0.5 of the total length of the tibia and does not reach its apex. It differs from the female of N. umbronitidella by having a yellow forewing base.

DESCRIPTION

Nemophora sumbana Kozlov, sp. nov.

Male. FWL 6.6‒7.5 mm, WLR 0.35‒0.40. Vertex bright ochreous; Glossy golden frons. PLB 0.3‒0.4 × vertical eye diameter, ochreous brown, with sparse raised ochreous brown piliform scales. Proboscis light brown, base anterolaterally with dense tuft of long and wide dark brown scales. Eyes enlarged, but not touching each other; interocular index 1.3‒1.5; occipital distance 0.05‒0.10. Antenna 3.0‒3.9 × FWL. Scape and basal 5‒8 flagellomeres ochreous brown, dorsally slightly thickened by ochreous scales; then color of flagellum sharply changes to dark coppery brown, with irregular white marks on lateral sides of some flagellomeres; these marks never form complete rings. At about middle of flagellum its color steadily changes to bronze, and apical 5‒15 flagellomeres are white in some specimens. Tegulae and thorax brown to bronze; tegulae with brassy green tint. Forewing bronze, with ocher pattern. Basal field with three glossy bronze longitudinal stripes; costal silver stripe reaches 0.30–0.35 × FWL; external border of basal field oblique, reaching costa at 0.4 and dorsum at 0.2 × FWL. Oblique band next to basal field of about same width at costa and dorsum, of same ochreous color as forewing base, except for narrow glossy bronze marginal lines. Oblique ochreous band linking costa with outer wing margin bordered by dotted narrow line of dark brown scales; its dorsal part extends along outer wing margin only towards wing base. Bronze background of distal part of forewing suffused with yellow scales, which form diffuse spot along external border of oblique ochreous band. Bronze fringe. Hindwing brown, with coppery tint; costal area yellowish grey; fringe brown. Legs glossy bronze to yellow; apices of tibiae and all tarsomeres brown. Epiphysis at 0.55, not reaching apex of tibia. Abdomen brown to bronze.

Male genitalia. Tegumen dome-shaped, with small medial ridge. Socii 1.6 × medial diameter of phallus. Vinculum 2.8 × length of valva, with slightly convex lateral margins and nearly straight distal margin with small medial protuberance. Tip of valve at about same level as tip of tegument. Ventral margin of valve with small lobe at 0.5 × total length; dorsal valvar margin almost straight; tip of valve rounded. Valve fused basally up to 0.3 × total length; internal valvar margins indistinct. Anellus 0.25 × length of valve. Transtilla with small triangular medial process. Juxta 0.55 × length of phallus, anchor-shaped; arrow head extremely wide (WLR 1.3), with rounded tip and pointed lateral arms. Phallus 0.90‒0.95 × length of vinculum, in lateral view gently S-shaped; base of phallus narrowly bell-shaped, tip pointed.

Nemophora timorella Kozlov, sp. nov.

Male. FWL 4.3‒5.0 mm, WLR 0.37‒0.39. Vertex light brown; frons with iridescent silver to light golden scales, and with row of pale ochreous brown piliform scales below antennal sockets. PLB 0.5‒0.6 × vertical eye diameter (1.3‒1.6 × length of scape), brown. Proboscis brown, base covered with dark coppery brown semi-erect elongated scales, forming small tuft. Eyes enlarged, occipitally closely approaching, with rounded dorsal margins; interocular index 1.3‒1.6, occipital distance 0.05‒0.07. Antenna 3.4‒3.9 × FWL. Scape ocherous brown, flagellum bronze, basal 20‒30 flagellomeres with rings of white scales, which gradually disappear towards apex. Tegulae and thorax light ochreous brown, with slight coppery tint on external margins of tegulae. Forewing bronze, with pale yellow basal field reaching costa at 0.35 and dorsum at 0.40 × FWL, ochreous yellow medial band, and oblique yellow band linking costa with outer wing margin. Basal field with two longitudinal glossy silver stripes with slight brilliant iridescence; lower stripe very narrow. Yellow medial band with sinuate margins, medially suffused with ochreous scales; on both sides bordered by narrow lines of dark brown scales. Bronze background of distal part of forewing suffused with ochreous scales, except for costal area near apex that is entirely bronze. Oblique yellow band, linking costa with outer wing margin, bordered by narrow line of dark brown scales; at outer wing margin it expands between veins M1 and CuA1 and is suffused with dark brown scales. Some of dark brown scales all over forewing show brilliant iridescence. Bronze fringe. Hindwing brown with coppery iridescence; costal area grey; semitranslucent anal fields; fringe brown to light brown. Bronze legs; bases of all tarsomeres light yellow. Epiphysis at 0.6, reaching apex of tibia. Abdomen coppery brown dorsally, brown with bronze iridescence ventrally.

Male genitalia. Onion-shaped tegument. Socii 1.6‒1.8 × medial diameter of phallus. Vinculum 2.7 × length of valva, with straight lateral margins and slightly convex distal margin. Tip of valve slightly extends beyond tip of tegumen. Ventral margin of valva medially with small lobe at 0.4 × total length; dorsal margin straight; tip of valva narrowly rounded. Valve fused basally up to 0.2 × total length; internal margins not visible. Fused parts of valves between ventral margins with distinct medial indentation. Anellus 0.35 × length of valve. Transtilla with wide triangular medial process. Juxta 0.6 × length of phallus; arrow head triangular, extremely wide (WLR 1.3), with pointed tip and short pointed lateral arms. Phallus 0.9 × length of vinculum, in lateral view shallowly C-shaped; tip narrow, hook-shaped; base narrowly funnel-shaped.

Nemophora umbronitidella Kozlov, sp. nov.

Male. FWL 5.2‒5.7 mm, WLR 0.35‒0.37. Vertex pale yellow above antennal sockets to ochreous brown along occipital margin; frons with iridescent silver to light golden scales through which brown color of head capsule may be visible, and with row of pale ochreous yellow piliform scales below antennal sockets. PLB 0.5 × vertical eye diameter (0.8‒0.9 × length of scape), light brown. Proboscis brown, base densely covered with dark coppery brown semi-erect elongated scales, forming characteristic tuft. Eyes enlarged, occipitally closely approaching, with rounded dorsal margins; interocular index 1.3‒1.4, occipital distance 0.05‒0.07. Antenna 3.7‒4.1 × FWL. Scape yellow, flagellum coppery brown, basal 27‒32 flagellomeres with rings of white scales, which gradually disappear towards apex. Tegulae and thorax dark ochreous brown. Forewing bronze, with dark ochreous brown basal field reaching costa at 0.35 and dorsum at 0.30 × FWL, ochreous yellow medial band, and oblique yellow band linking costa with outer wing margin. Basal field with two longitudinal glossy silver stripes with slight brilliant iridescence; lower stripe very narrow. Ocherous yellow medial band with sinuate margins, on both sides bordered by narrow lines of dark brown scales. Bronze background of distal part of forewing suffused with yellow scales. Oblique yellow band linking costa with outer wing margin bordered by narrow line of dark brown scales; at outer margin it expands between veins RS4 and CuA2 and is suffused with brown scales. Some of dark brown scales all over forewing show brilliant iridescence. Fringe bronze. Hindwing brown with coppery iridescence; costal area grey; semitranslucent anal fields; fringe brown to light brown. Bronze legs; bases of all tarsomeres white to light yellow. Epiphysis at 0.65, reaching apex of tibia. Abdomen brown with bronze iridescence.

Female. FWL 5.6mm. Base of antenna thickened by pressed dark brown scales (distal part of antenna missing). Otherwise similar to male.

Male genitalia. Onion-shaped tegument. Socii 1.3 × medial diameter of phallus. Vinculum 2.2 × length of valva, with straight lateral margins and slightly convex distal margin. Tip of tegumen slightly extends beyond tip of valvae. Ventral margin of valve with small lobe at 0.55 × total length; dorsal margin straight; tip of valva narrowly rounded. Valve fused basally up to 0.4 × total length; internal margins not visible. Fused parts of valves between ventral margins with distinct triangular protuberance. Anellus 0.2 × length of valve. Transtilla with wide triangular medial process. Juxta 0.55 × length of phallus; arrow head anchor-shaped, extremely wide (WLR 1.1), with widely rounded tip and long pointed lateral arms. Phallus 0.95 × length of vinculum, in lateral view shallowly C-shaped; tip narrow, base widely funnel-shaped.

Nemophora wegneri Kozlov, sp. nov.

Male. FWL 5.3‒5.9 mm, WLR 0.36‒0.42. Vertex with dark brown to brown piliform scales along occipital margin and above antennal sockets, and pale yellow scales between compound eyes; Glossy golden frons. PLB 0.45‒0.55 × vertical eye diameter, ochreous brown, with sparse raised dark brown scales. Proboscis light brown, base laterally with bronze to coppery bronze scales which, however, do not form a tuft. Eyes enlarged, occipitally closely approaching; interocular index 1.15‒1.35; occipital distance 0.05‒0.15. Antenna 2.9‒3.5 × FWL. Scape dark brown, ventrally in some specimens with a few yellow scales; basal 0.6‒0.7 of flagellum with alternating rings of dark brown and white scales; apical part of flagellum silver to white. Tegulae dark brown with bronze tint; thorax dark brown, except for bright yellow posterior margin of mesothorax. Forewing bright yellow with ochreous pattern. Basal field with two glossy golden longitudinal stripes; costal margin dark brown; external border oblique, reaching ribs at 0.35 and dorsum at 0.25 × FWL. Oblique stripe next to basal field at costa narrower than at dorsum (0.13 vs. 0.22 × FWL, respectively), ochreous, clearly contrasting yellow color of forewing base, except for narrow glossy bronze lines preceding dark brown margins. Transverse band and oblique band linking costa with outer wing margin bright yellow, bordered near wing margins by dotted narrow lines of dark brown scales and in medial zone of forewing by narrow glossy golden lines; yellow spot expands along outer wing margin up to wing apex. Bronze background of distal part of forewing suffused with ochreous scales forming compact spot along external border of oblique ochreous band. Fringe bronze, with few ochreous scales forming dotted marginal lines. Hindwing brown, with coppery tint; costal area grey; fringe brown. Legs glossy bronze to yellow; apices of tibiae and all tarsomeres brown. Epiphysis at 0.5, reaching apex of tibia. Abdomen brown to bronze.

Female. FWL 5.0‒6.0 mm. Antenna 1.5‒1.6 × FWL, basal 0.30‒0.35 of flagellum dorsally with dense cover of raised scales forming very thick brush, which is ochreous yellow except for tip where its color turns to dark brown; distal part of flagellum dark bronze, with irregular markings of white scales. Tegulae and thorax bright yellow. Otherwise similar to male.

Male genitalia. Tegumen dome-shaped, with small medial ridge. Socii oval, 1.2 × medial diameter of phallus. Vinculum 2.6‒2.7 × length of valva, with slightly convex lateral margins and gently W-shaped distal margin. Tip of valve at about same level as tip of tegument. Ventral margin of valve with small lobe at 0.6 × total length; dorsal valvar margin almost straight; tip of valve pointed. Valvae are fused basally up to 0.3 × total length and also fused to vinculum; internal valvar margins indistinct. Anellus 0.3 × length of valve. Transtilla with wide triangular medial process. Juxta 0.55 × length of phallus; arrow head triangular, extremely wide (WLR 1.3), with pointed tip and pointed lateral arms. Phallus 1.1 × length of vinculum, in lateral view gently S-shaped; tip pointed, with prominent ventral lobe; base of phallus narrowly bell-shaped.

Nemophora longipeniculella Kozlov, sp. nov.

Female. FWL 4.9‒5.1 mm, WLR 0.35. Vertex and fronts brown. PLB 1.0‒1.1 × vertical eye diameter (1.0‒1.1 × length of scape), brown. Proboscis brown, base covered with dark coppery brown semi-erect elongated scales forming small tuft. Antenna >1.3 × FWL. Scape and basal part of flagellum dark coppery brown, dorsolaterally thickened by semi-erect dark brown scales; brush formed by these scales reaches 0.95 × FWL; flagellum gray beyond this brush. Tegulae and thorax ochreous yellow to yellow. Forewing ochreous brown, with pale yellow basal field expanding to 0.4 × FWL at both costa and dorsum, pale yellow medial band, and oblique yellow band linking costa with outer wing margin. Basal spot reduced to dark line along costa; forewing base separated from bronze background by interrupted line of coppery brown scales. Pale yellow medial band with straight internal margin and sinuate external margin, on both sides bordered by interrupted lines of coppery brown scales. Oblique yellow band linking costa with outer wing margin bordered by sparse coppery brown scales; this band expands into wide spot along outer margin. Costal part of forewing bronze near apex. Fringe brown. Hindwing dark brown with coppery iridescence; costal area yellowish grey; fringe brown to light brown. Legs coppery brown to bronze; bases of all tarsomeres light yellow. Epiphysis at 0.25, unusually long, reaching apex of tibia. Abdomen dorsally ochreous brown, ventrally bronze at base to coppery brown at apex.

Nemophora brevipeniculella Kozlov, sp. nov.

Female. FWL 4.7‒5.0 mm, WLR 0.33‒0.38. Vertex brown; frons with iridescent silver to light golden scales, and with row of brown piliform scales below antennal sockets. PLB 0.9‒1.0 × vertical eye diameter (1.0 × length of scape), brown. Proboscis brown, base covered with dark coppery brown semi-erect elongated scales, forming small tuft. Antenna 2.0 × FWL. Scape and basal part of flagellum dark brown, dorsolaterally thickened by semi-erect dark brown scales; brush formed by these scales reaches 0.8 × FWL. Flagellum bronze beyond this brush; 10‒15 flagellomeres next to brush with white rings. Tegulae and thorax yellow. Forewing bronze, with pale yellow basal field expanding to 0.3 × FWL at both costa and dorsum, pale yellow medial band, and oblique yellow band linking costa with outer wing margin. Basal spot dark brown, connected with dark brown band separating yellow forewing base from bronze background of distal part of forewing. Pale yellow medial band almost straight, on both sides bordered by dark brown bands. Bronze field between basal field and medial fascia densely suffused with dark brown scales. Oblique yellow band linking costa with outer wing margin bordered by dark brown scales; irregular spot along outer wing margin dark brown, sparsely suffused with ochreous brown scales. Costal part of forewing bronze near apex. Fringe brown. Hindwing dark brown with coppery iridescence; costal area light yellow; fringe brown to light brown. Legs coppery brown to bronze; bases of all tarsomeres light yellow. Epiphysis at 0.5, not reaching apex of tibia. Abdomen dorsally brown with coppery iridescence, ventrally bronze except terminal sternite which is coppery brown; lateral parts of tergites with yellow scales.

Original research

Mikhail V. Kozlov (2024). Description of six new species forming the sumbana species group of the genus Nemophora Hoffmannsegg (Lepidoptera, Adelidae) from the Lesser Sunda Islands in Indonesia. Zootaxa 5543 (1): 111–122, DOI:10.11646/zootaxa.5543.1.6

Dlium theDlium