Distribution of Ecnomus McLachlan, 1864 (Trichoptera, Ecnomidae) from the Lower Mekong River with a description of Ecnomus stungtrengensis new species Author Laudee, Pongsak https://orcid.org/0000-0003-3819-7980 Faculty of Innovative Agriculture and Fishery Establishment Project, Prince of Songkla University, Surat Thani Campus, Surat Thani, Thailand pongsak.l@psu.ac.th Author Malicky, Hans Sonnengasse 13, Lunz am See, Austria Author Seetapan, Kriengkrai School of Agriculture and Natural Resources, University of Phayao, Phayao, Thailand Author Thamsaenanupap, Penkhae Faculty of Environment and Resource Studies, Mahasarakham University, Maha Sarakham, Thailand Author Karnkasem, Supawit Faculty of Innovative Agriculture and Fishery Establishment Project, Prince of Songkla University, Surat Thani Campus, Surat Thani, Thailand Author Vongsombath, Chanda Faculty of Environmental Sciences, National University of Laos, Dong Dok Campus, Vientiane, Laos Author Oo, Sai Sein Lin No. 208, Southern Quarter, Muse Township, Shan State, Myanmar Author Kong, Chamroeun Kampong Speu Institute of Technology, Kampong Speu, Cambodia Author Zalyan, Pome Department of Zoology, University of Kalay, Myanmar, Kalay, Myanmar Author Morse, John C. https://orcid.org/0000-0003-3187-4045 Clemson University, Clemson, United States of America text Biodiversity Data Journal 2022 2022-12-01 10 94936 94936 http://dx.doi.org/10.3897/BDJ.10.e94936 journal article http://dx.doi.org/10.3897/BDJ.10.e94936 1314-2828-10-e94936 2CBB42259DF34085B0A7526208793791 20C633763EA65582B9FFBB9BB092904A Ecnomus stungtrengensis Laudee & Malicky sp. n. Ecnomus stungtrengensis Ecnomus McLachlan, 1864 Ecnomus stungtrengensis Type species: Ecnomus tenellus (Rambur, 1842) (monobasic) Materials Type status: Holotype . Occurrence : sex: male ; lifeStage: Adult ; occurrenceStatus: present; preparations: whole animal; occurrenceID: 867C6D9C-CF80-52DF-A6A2-C0B38E0A1A4C ; Taxon : scientificName: Ecnomus stungtrengensis; nameAccordingTo: Province ; kingdom: Animalia ; phylum: Arthropoda ; class: Insecta ; order: Trichoptera ; family: Ecnomidae ; genus: Ecnomus ; specificEpithet: stungtrengensis; scientificNameAuthorship: Laudee and Malicky ; Location : continent: Asia ; country: Cambodia ; countryCode: KH; stateProvince: Krung Stung Treng ; county: Cambodia ; municipality: Krung Stung Treng ; locality: Tonle Sekong River , 13°32 '00" N , 105°59 '56" E ; minimumElevationInMeters: 42; Identification: identifiedBy: Laudee and Malicky ; Event: samplingProtocol: UV light trap ; samplingEffort: 1 trap-night; year: 2019; month: 4; day: 8; Record Level: type: Trichoptera; language: English; institutionCode: PSUNHM; basisOfRecord: PreservedSpecimen Type status: Paratype . Occurrence : sex: male ; lifeStage: Adult ; occurrenceStatus: present; preparations: whole animal; occurrenceID: FCDEB7C7-94E0-50B2-BC0A-8E6B9AB20351 ; Taxon : scientificName: Ecnomus stungtrengensis; nameAccordingTo: Province ; kingdom: Animalia ; phylum: Arthropoda ; class: Insecta ; order: Trichoptera ; family: Ecnomidae ; genus: Ecnomus ; specificEpithet: stungtrengensis; scientificNameAuthorship: Laudee and Malicky ; Location : continent: Asia ; country: Cambodia ; countryCode: KH; stateProvince: Krung Stung Treng ; county: Cambodia ; municipality: Krung Stung Treng ; locality: Tonle Sekong River , 13°32 '00" N , 105°59 '56" E ; minimumElevationInMeters: 42; Identification : identifiedBy: Laudee and Malicky ; Event : samplingProtocol: UV light trap ; samplingEffort: 1 trap-night; year: 2019; month: 4; day: 8; Record Level : type: Trichoptera ; language: English ; institutionCode: 2 males (PSUNHM), 2 males (CHM), 2 males (CUAC); basisOfRecord: PreservedSpecimen Description Adult habitus : Specimens in alcohol with head, thorax, forewings, abdomen and legs light brown. Male (Fig. 3 ) Length of each male forewing 4.0 mm (3.5-4.5, n = 5); Tergum IX somewhat rounded, anterior margin bilobed, posterior margin slightly incised in dorsal view (Fig. 3 A); trapezoidal, nearly triangular and truncate anteriorly in lateral view (Fig. 3 B). Sternum IX ovoid in lateral view (Fig. 3B); isosceles trapezoid in ventral view and evenly concave posteriorly (Fig. 3 C); Superior appendages long, slender, strongly and evenly curved inwards posteriorly with numerous long setae, spiny setae subapically in dorsal view (Fig. 3 A); in lateral view, superior appendages, long, slender, tapered and bent downwards with numerous spiny setae apically (Fig. 3 B). Process of segment X triangular with strong apical setae in lateral view. Inferior appendages cylindrical with numerous small setae, bent slightly inwards and upwards subapically, rounded apically in lateral view (Fig. 3 B); in ventral view, crescent-shaped, expanded basally with inner submedial lobe, rounded apicolaterally, acute apicomesally (Fig. 3 C). Paramere spoon-like, bent downwards subapically, rounded apically. Phallus shaped like candle flame, pointed apically in lateral view (Fig. 3 B); in ventral view, conical with pointed apex (Fig. 3 C). Diagnosis The male genitalia of E. stungtrengensis sp. n. are similar to those of E. robustior Ulmer, 1951, E. pseudotenellus Ulmer, 1930 and E. projectus Li & Morse, 1997, but clearly different from those species by the shape of the superior appendages. In the new species, they are slender and bent downwards distally in lateral view, but in the other three species, they are straight and not bent in lateral view. In dorsal view, the superior appendages of the new species are bent evenly mesad to define 3/4 of a circle, but in the other three species, they are straight. Etymology The species is named for the type locality, Krung Stung Treng Province, with the epithet having masculine gender, corresponding with the gender of the genus. Distribution Cambodia (Krung Stung Treng Province).