Discovery of new Caddisfly species to cience from the Cuc Phuong National Park, Ninh Binh, Vietnam

The Trichoptera fauna of Vietnam has been moderately studied over the last two decades. An initial country list was provided by Armitage, Mey, Arefina, and Schefter (2005) showing a total of 334 species. This number was considered by the authors to be a considerable underestimate of the size of the resident fauna bearing in mind the sporadic collecting in the country and the lack of thorough inventories in nearly all Vietnamese provinces. Due to the current absence of long-term collecting programs including multi-seasonal sampling all over the country, the knowledge of the Vietnamese fauna concerning registered species is still increasing only gradually.

The examination of small samples of caddisflies collected in the Cuc Phuong National Park in Vietnam in 2019 resulted in the identification of 45 species. All species are listed including 10 species which were determined to genus level only. Five new species were identified, which are described herein as: Chimarra calcarata sp. n., Ecnomus eberhardmeyi sp. n., Pseudoneureclipsis bicolorata sp. n., Adicella guttifera sp. n. and Oecetis macensis sp. n. The male genitalia are illustrated.

New species to science:

1) Chimarra calcarata sp. n. (Figure 1)

The family Philopotamidae

 Length of forewing 4.8 mm; head and thorax dark brown, setal warts on vertex light brown; antennae brown, becoming paler towards tips; palpi brown; eyes black; legs light brown, protarsal claw unmodified, spurs 3.4.4.; forewings dark brown, venation with stalk of discoidal cell nearly straight, basal veins thickened, crossvein r-rs to middle of discoidal cell, s crossvein unpigmented; hindwings colour as forewings, Sc and R1 fused, fork 3 with long stalk; abdomen, segment VIII with short, triangular process ventrally; sternum V with small, round, unpigmented openings of sternal glands. Male genitalia (Figure 1).

Figure 1. Male genitalia of Chimarra calcarata sp. n.: (A) lateral, scale 0.5 mm; (B) ventral; (C) dorsal; (D) sternum V, ventral, scale 0.5 mm (Mey & Vu, 2022)

2) Ecnomus eberhardmeyi sp. n. (Figure 2)

The family Ecnomidae

Length of forewing 4.2 mm, wing span 10 mm; head brown, setal warts on vertex dark brown, frons light brown with yellow hairs; antennae yellow; eyes black; palpi dark brown, ventral sides with long setae; thorax dark brown dorsally, hairs greybrown; legs light brown, spurs 3.4.4.; forewings yellow-brown (Figure 6C), ellow spots on costal margins and termen, costa and underside of costal area with long, dark hairs, venation with very short Sc; cross vein m-cu and M vein before bifurcation of M1þ2 depigmented, median cell long, fork 3 and 4 without stalks; hindwings membranous. Male genitalia (Figure 2).

Figure 2. Male genitalia of Ecnomus eberhardmeyi sp. n.: (A) lateral, scale 0.5 mm; (B) dorsal; (C) ventral (Mey & Vu, 2022)

3) Pseudoneureclipsis bicolorata sp. n. (Figure 3)

The family Pseudoneureclipsidae

 Length of forewing 3.8–4.1 mm; head and thorax dark brown, setal warts on vertex with golden-yellow hairs, frons with dark brown hairs; antennae yellow, some black hairs on dorsal articulations; palpi brown; eyes black; legs light brown, spurs 3.4.4.; costal half of forewings dark brown (Figure 6B), anal half with golden brown hairs, forewing venation with forks 1, 2, 3, 4, hindwings with forks 2, 3 and 4.; venulae of sternum II forming ‘M’ letter (Figure 6G), sternum V with short venula from dorsal margin (Figure 3D). Male genitalia (Figure 3A–C).

Figure 3. Genitalia of Pseudoneureclipsis bicolorata sp. n., male: (A) lateral, scale 0.5 mm; (B) ventral; (C) dorsal; (D) sternum V, lateral; female: (E) lateral; (F) dorsal; (G) sternum II-III, ventral, scale 0.5 mm (Mey & Vu, 2022)

4) Adicella guttifera sp. n. (Figure 4)

The family Leptoceridae

 Length of forewing 5.2 (#)–6.2 ($) mm; head vertex and thorax brown, setal warts on vertex with pale yellow hairs, frons yellow; antennae yellow, some black hairs on dorsal articulations; palpi brown; eyes black; legs light brown, spurs 1.2.2. (#), 0.2.2. ($); costa and costal field of upper and underside of forewings with long, light brown hairs (Figure 4D), wing membrane clothed with pale-yellow hairs, some brown hair patches on subapical costa, in discoidal cell and on cross-veins, a patch of erected black hairs close to middle of Cu2, brown fringe hairs of hindwings very long at base becoming shorter towards apex; venation as in Figure 4D. Male genitalia (Figure 4A–C).

Figure 4. Male genitalia and wing venation of Adicella guttifera sp. n.: (A) lateral, scale 0.5 mm; (B) ventral; (C) dorsal; (D) wing venation (Mey & Vu, 2022)

5) Oecetis macensis sp. n. (Figure 5)

The family Leptoceridae

Length of forewing 5.5 mm; head and thorax yellow, setal warts on vertex with tufts of pale, yellow hairs, long and directed backwards; antennae yellow, some black hairs on dorsal articulations; palpi pale yellow; eyes black; legs light brown, spurs 0.2.2. (#); forewings with long, light brown hairs on costa, wing membrane sparsely clothed with short pale-yellow hairs, dark points on cross-veins, end points of veins on wing margin and on vein bifurcations, anastomosis including base of fork 1 nearly a continuous dark brown line, fork 5 petiolated; terga VI and VII of abdomen each with pair of honeycomb reticulation areas, tergum VIII with single, large honeycomb reticulation area, covering most of dorsal portion of segment IX (Figure 5D). Male genitalia (Figure 5A–C).

Figure 5. Male genitalia of Oecetis macensis sp. n.: (A) lateral, scale 0.5 mm; (B) dorsal; (C) ventral; (D) tergum VII-IX, scale 0.5 mm (Mey & Vu, 2022)

Figure 6. Adults: (A) Chimarra akkaorum Chantaramongkol and Malicky, 1989, male; (B) Pseudosneureclipsis bicolorata sp. n., male paratype; (C) Ecnomus eberhardmeyi sp. n., holotype, male; (D) Hyalopsyche parvula Martynov, 1935, male (Mey & Vu, 2022)

News: Vu Van Lien, The Vietnam National Museum of Nature, VAST
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