Preheterobathmia grimaldii, Mey, 2024

Mey, Wolfram, 2024, Preheterobathmia gen. nov. - a new non-glossatan taxon from Myanmar amber tentatively assigned to Heterobathmiidae (Insecta, Lepidoptera), Nota Lepidopterologica 47, pp. 1-10 : 1

Preheterobathmia grimaldii sp. nov.

Figs 1a-d , 2-7

Material.

Holotype, female, Burmese Amber , deposited in NIGP - Nanjing Institute of Geology and Palaeontology, Nanjing, P. R. China; inventory number: NIGP 203445.

Preservation.

The fossil is embedded in a flattened, oval piece of amber (length: 17 mm) (Fig. 1a ). This female is completely preserved, but in a position with the right wings overlapping and covering the body (Fig. 1b, c ) on the side illustrated. Head, thorax and abdomen are only visible in lateral view. Small organic particles and several air bubbles are present in the amber matrix as well as close to the head and between the legs.

Etymology.

The specific epithet is dedicated to D.A. Grimaldi for his important contributions to palaeoentomology.

Description.

Female: Length of body 4.0 mm, forewings 4.2 mm; head vertex with tuft of erected, piliform scales directed dorsad and frontad; erected hairs on lateral sides of frons and subgenae below eyes; eyes rounded, hemispherical; ocelli very small; labrum large and broad, apical portion densely covered by small hairs; maxillary palpi of the micropterigid type, basal segment with long hairs, second and third segment of equal length, without intersegmental membrane, fourth segment longest, terminal segment short; labial palpi not reduced, three-segmented, final segment acute at apex; antenna long, ¾ of wing length, with 44 flagellomeres, dorsally covered by lamellar scales, ventral side with short hairs and at least one pair of long, spreading setae (Fig. 7 ); legs with spur formula 0.4.4.; forelegs with epiphysis, carrying a comb of small denticles at its ventral blade, spines of different strength present on tibia and tarsal segments of all leg pairs (Figs 2 , 3 ).

Wings and venation (Fig. 4 ): Both wings broad, densely covered by overlapping scales, producing a pattern of darker and paler patches, scales on membrane sub-quadrangular and with apical margins obtuse (Fig. 6 ), without indentations, scales of wing margin elongate, club-shaped and acute at apex (unidentate), scattered piliform, erected scales present at veins and membrane on both wings; hindwing scaling similar to forewing; jugum in both wings apparently absent. Forewing C with long bristles at the basal lower surface, SC apically forked, R1 simple, cross-veins sc-r and r1-r2 absent, pterostigma absent, all radial veins free from accessory cell (= aureole), M 3-branched, Cu2 atrophied before wing margin, anal veins (A1+2+3) with long basal loop. Hindwing with SC and R1 unforked, without cross-veins, R branches not stalked, M with three branches emanating from long median cell, weak m-cu present, Cu2 present as short vein at the base, anal veins thin, A1 and A2 connected by cross-vein.

Abdomen with elongate scales in horizontal position on sternites (Fig. 1d ), sternum V with small pad-like elevation and surface modification; segment VIII separated into sternum and tergum, the former slightly overlapping with the ventral part of segment IX in the female.

Female genitalia (Figs 1d , 5 ): Segment IX large, with triangular shape in lateral view, tapering distally to small lobes, not separated from segment IX, surface devoid of scales but vestiture of small and long setae present on dorsal, lateral and apical sides, in central position a small protuberance with short setae; gonopore and anus (or of a cloaca?) on ventral side of segment IX in a narrow, elongate depression laterally bordered by membranous walls.

Figures

Figure 1. Female holotype of Preheterobathmia grimaldii sp. nov. a. Amber piece with inclusion of Preheterobathmia gen. nov.; b, c. Moth in lateral position under different illumination; d. Close-up of abdominal tip with female genitalia.

Figures 2 - 7. Preheterobathmia grimaldii sp. nov., female. 2. Head; 3. Middle and hind leg; 4. Wings; 5. Abdomen with genital segments in lateral view; 6. Scales of forewing; a, b. At membrane; c, d. Termen margin; e. Costal fringe; 7. Flagellomeres from the middle section of antenna, ventral view. Scale bars: 2 mm (4); 1 mm (1); 0.5 mm (3, 5); 0.1 mm (7); 0.05 mm (6).