Triaenodes tipmaneei Nannaphat and Malicky, 2025

Laudee, Pongsak, Malicky, Hans, Takenaka, Masaki, Sawangarrom, Phuwadon & Suwannarat, Nannaphat, 2025, A New Species of Triaenodes (Trichoptera: Leptoceridae), based on morphological and molecular data, from Kaeng Khoi Waterfall, Chumphon Province, southern Thailand, Zootaxa 5594 (2), pp. 387-394 : 389-391

Triaenodes tipmaneei Nannaphat and Malicky sp. nov.

( Figs 1A–1E )

Type material. Holotype, ♂: Thailand, Chumphon Province, Pathio District, Kaeng Khoi Waterfall , 10°41’05”N, 99°16’43”E, 150 m a.s.l., 23. xii. 2023, leg. Nannaphat Suwannarat ( KMITL).

Paratypes: 7 ♂♂ and 6 ♀♀, same data as holotype ( KMITL) .

Paratypes. 4 ♂♂ and 2 ♀♀, same data as holotype ( CHM) .

Etymology. The species is named for Mr. Kamronwit Thipmanee, He is an executive vice president for the Chumphon Campus.

Description. Head, thorax, and legs yellow brownish. Body light yellowish brown. Forewings yellowish brown. Length of each male forewing 3.2–4.8 mm (N = 8), of holotype male forewing (4.8), of female forewing 3.0– 4.2 mm (N = 6).

Male genitalia ( Figs 1A–1E ). Segment IX dorsal region in dorsal view ( Fig. 1A ) relatively short longitudinally and slightly convex anteriorly and with pair of short, bare papillae posteriorly; in lateral view ( Fig. 1B , Seg IX) ventrolateral region five times as long as dorsal region and semicircular anteriorly, slightly concave posteriorly; in ventral view ( Fig. 1C , Seg IX) subquadrate with shallow concavity anteriorly. Preanal appendages (Pre) slender with numerous setae, half as long as lower processes of segment X ( Figs 1A, 1B ). Upper part of segment X (up X) bilobed apically and setose, originating between pair of apicodorsal papillae of segment IX and pair of preanal appendages ( Figs 1A, 1B ). Lower part of segment X divided into pair of very long, sword-like processes slender and straight and parallel for most of their length in dorsal view ( Fig. 1A ), tall in basal 1/3 and slender and downcurved in lateral view ( Fig. 1B , lo X). Inferior appendages in lateral view ( Fig. 1B , Inf) without recurved processes; each with dorsal branch divided into subtriangular apicodorsal lobe and two slender apical processes, upper process curved upward and bifid, lower process downcurved, slender with pointed apex; main body of each appendage with short slender apicolateral process with long apical setae, apicomesal process short and triangular, apicoventral process stout with pointed apex directed caudad ( Fig. 1B ); in ventral view ( Fig. 1C , Inf), main body of each inferior appendage somewhat long-triangular and covered with numerous setae, with short acute process at mid-length on mesal margin. Phallus slender, basal 3/5 laterally compressed and apical 2/5 spoon-like in dorsal view ( Fig. 1E ), with dark subapical phallotremal sclerite torch-like in lateral view ( Fig. 1D ), V-shaped in dorsal view ( Fig. 1E ).

Female genitalia ( Figs 2A–C ). Segment IX (Seg IX) fused with setose preanal appendages and with pair of small papillae (Pap) apicodorsally in dorsal view ( Fig. 2A ); in lateral view ( Fig. 2B , Seg IX), papillae somewhat oval and thumb-like. Preanal appendages setose, in dorsal view ( Fig. 2A ) triangular, more nearly circular in lateral view ( Fig. 2A ), in ventral view ( Fig. 2C ), scale-like and moderately large. Segment X in dorsal view ( Fig. 2A , Seg X) short, fused with preanal appendages. Lamellae setose, in lateral view ( Fig. 2B , Lam) subquadrate and beaklike apically, in ventral view ( Fig. 2C , Lam) pear-like. Gonopod plates in ventral view ( Fig. 2C , Gon) bird-head-like, concave mesally and acute anteromesally.

Diagnosis. Triaenodes themis Malicky & Prommi 2006 is the most similar species and lives also on the southern peninsula part of Thailand where the new species was found. The male genitalia of T. tipmaneei sp. nov. are distinguished from those of T. themis and the other species in the genus by the shape of inferior appendages. Inferior appendages of the new species are without recurved processes; the dorsal branch is divided into a dorsal lobe and two apical processes, the upper process curved upward and triangular apicodorsally and bifid apicoventrally, and the lower process slender with pointed apex; main body of the appendage is with short slender apicolateral process, mesal process short and pointed, ventral process stout, pointed apex. Each inferior appendages of T. themis has a dorsal branch that is not divided apicoventrally and the main body is without a mesal process.

The female genitalia of Triaenodes spp. found in Thailand and southeast Asia are mostly unknown. However, Yang & Morse (2000) described females of several species of Triaenodes from China such as those of T. foliformis Yang & Morse 2000 , T. qinglingensis , and T. unanimis McLachlan 1877 . However, these can be separated by the shapes of the lamellae. Triaenodes spp. found from China have lamellae that are spoon like, but the new species has sack-like lamellae, each with a beak-like apex in lateral view. According to the molecular analysis, Triaenodes tipmaneei sp. nov. has a close genetic relationship to T. themis with 8.5 percent difference between these two.

Molecular analysis. As shown in Figure 3 , Triaenodes tipmaneei sp. nov. was genetically differentiated from all analyzed species in the same genus. The closest phylogenetic relationship was with T. themis , and genetic differentiation between these two species was also confirmed ( Fig. 3 ). The genetic distance (p -distance) based on the mtDNA COI region between T. tipmaneei sp. nov. and T. themis was 8.5 percent.

Figures

FIGURES 1–3. Triaenodes tipmaneei sp. nov., 1A–1E, male genitalia: 1A, dorsal; 1B, left lateral; 1C, ventral; 1D, phallus, left lateral; 1E, phallus, ventral. 2A–2C, female genitalia: 2A, dorsal; 2B, left lateral; 2C, ventral. 3, Estimated phylogenetic relationships using the neighbor-joining clustering method for Triaenodes spp. based on the mtDNA COI region. The sequence of Achoropsyche duodecimpunctata was included as the outgroup. Gon = gonopod plate (paired), Inf = inferior appendage (paired), Lam = lamella (paired), lo X = lower part of segment X (paired), Pap = papilla (paired), Pre = preanal appendage (paired), Seg IX = segment IX, Seg X = segment X.