taxonID	type	description	language	source
1D59C5B69C265E9EAD3EC2E2AD6EE093.taxon	distribution	Distribution. Brazil (Maranhão, Pará).	en	Quinteiro, Fábio B., Costa, Anne M., Saldanha, Gabriel, Moura, Laisse, Assunção, Otávio T., Juen, Leandro (2025): A new species of Oecetis McLachlan, 1877 (Trichoptera, Leptoceridae) and new distributional records of Trichoptera in the eastern Amazon. ZooKeys 1263: 365-377, DOI: 10.3897/zookeys.1263.151613
D432D38E65C45EA19A30430EDE7E4F03.taxon	distribution	Distribution. Argentina, Bolivia, Brazil (Bahia, Espírito Santo, Maranhão, Minas Gerais, Pará, Paraná, Piauí, Roraima), Colombia, Ecuador, Guyana, Paraguay, Peru, Venezuela.	en	Quinteiro, Fábio B., Costa, Anne M., Saldanha, Gabriel, Moura, Laisse, Assunção, Otávio T., Juen, Leandro (2025): A new species of Oecetis McLachlan, 1877 (Trichoptera, Leptoceridae) and new distributional records of Trichoptera in the eastern Amazon. ZooKeys 1263: 365-377, DOI: 10.3897/zookeys.1263.151613
7D481350DF585B4EAFF9C5E259D7DCB3.taxon	distribution	Distribution. Brazil [new country record] (Pará), Peru, Suriname.	en	Quinteiro, Fábio B., Costa, Anne M., Saldanha, Gabriel, Moura, Laisse, Assunção, Otávio T., Juen, Leandro (2025): A new species of Oecetis McLachlan, 1877 (Trichoptera, Leptoceridae) and new distributional records of Trichoptera in the eastern Amazon. ZooKeys 1263: 365-377, DOI: 10.3897/zookeys.1263.151613
9166155C2F0F5358B8700E788683B249.taxon	description	Figs 1, 2, 3	en	Quinteiro, Fábio B., Costa, Anne M., Saldanha, Gabriel, Moura, Laisse, Assunção, Otávio T., Juen, Leandro (2025): A new species of Oecetis McLachlan, 1877 (Trichoptera, Leptoceridae) and new distributional records of Trichoptera in the eastern Amazon. ZooKeys 1263: 365-377, DOI: 10.3897/zookeys.1263.151613
9166155C2F0F5358B8700E788683B249.taxon	diagnosis	Diagnosis. Due to the honeycomb microstructure covering terga V – VIII, this species belongs to the O. testacea species group as defined by Quinteiro and Holzenthal (2017). It can be distinguished from other species in this group by having the dorsal portion of tergum X longer than the preanal appendage, cylindrical, and with an acute apex in dorsal view. Also, the inferior appendage has an enlarged basis and a rounded dorsal lobe which bears short, thick setae, and with an inward-directed apex.	en	Quinteiro, Fábio B., Costa, Anne M., Saldanha, Gabriel, Moura, Laisse, Assunção, Otávio T., Juen, Leandro (2025): A new species of Oecetis McLachlan, 1877 (Trichoptera, Leptoceridae) and new distributional records of Trichoptera in the eastern Amazon. ZooKeys 1263: 365-377, DOI: 10.3897/zookeys.1263.151613
9166155C2F0F5358B8700E788683B249.taxon	description	Description. Male. General color yellowish brown in alcohol (Fig. 1 A). Forewing length 5.0 – 5.9 mm, (n = 4), holotype 5.2 mm. Hindwing length 4.0 – 4.9 mm (n = 4), holotype 4.8 mm. Head yellowish brown (Fig. 1 A). Antennae three times length of forewing; scape stout; pedicel short. Anteromesal setal wart small, rounded; posterior setal wart rounded; posterolateral setal wart thin. Maxillary palps yellowish brown, 5 - segmented (Fig. 1 A); labial palps yellowish brown, 3 - segmented (Fig. 1 A). Thorax. Pterothorax brown. Forewings yellowish brown (Fig. 1 A, B); dark bands present on forewing over chord (s, r-m, m-cu); dark spots present on forks, junctions, and vein tips; colored setae absent; forks I and V present, both rooted; sectoral crossvein (s) distal of r-m; m-cu crossvein basal of r-m (Figs 1 B, 2 A). Hindwings yellowish brown; forks I and V present (Figs 1 C, 2 B). Legs yellowish brown. Tibial spur formula 1, 2, 2; foreleg tibial spur ½ length of mid- and hindleg spurs. Abdomen. Reticular patches (honeycomb texture, Fig. 1 D, E) on terga V – VIII. Acrotergite present between segments VIII and IX (Figs 1 D, E, 2 C, D). Segment IX short, medially enlarged and posterolateral process absent in lateral view (Figs 1 D, 2 C); wider than inferior appendages in ventral view, with anterior margin concave (Figs 1 F, 2 E). Preanal appendages short, apex rounded, basally broadened in lateral view, with apical setae (Figs 1 D, 2 C), ovate, with round base and acuminate apex in dorsal view (Figs 1 E, 2 D). Tergum X longer than preanal appendage, dorsoventrally divided in lateral view (Figs 1 D, 2 C); dorsal portion slightly longer than ventral, tapering apically, with apex acuminate, ventral portion mesally divided, basally broadened, apex rounded in dorsal view (Figs 1 E, 2 D). Inferior appendage 1 - segmented, setose, basally enlarged; dorsal lobe enlarged, apex rounded, projecting dorsad, with stout, short setae in lateral view (Figs 1 D, 2 C); ventral lobe absent (Figs 1 D – F, 2 C – E); distal lobe concave, smoothly apically tapering, apex acuminate, slightly curved inward, obtuse angle formed by dorsal and distal lobes (Figs 1 D – F, 2 C – E). Phallic apparatus symmetrical, elongate, cylindrical, ventrally bent; phallobase basally large, sclerotized, slightly constricted subasally (Figs 1 D, 2 F, G); endotheca twice as long as phallobase and 1 - lobed in lateral view (Figs 1 D, 2 F), same length in ventral view (Fig. 2 G); phallic spines absent; phallotremal sclerite absent (Figs 1 D, 2 F, G). Female and immatures. Unknown.	en	Quinteiro, Fábio B., Costa, Anne M., Saldanha, Gabriel, Moura, Laisse, Assunção, Otávio T., Juen, Leandro (2025): A new species of Oecetis McLachlan, 1877 (Trichoptera, Leptoceridae) and new distributional records of Trichoptera in the eastern Amazon. ZooKeys 1263: 365-377, DOI: 10.3897/zookeys.1263.151613
9166155C2F0F5358B8700E788683B249.taxon	etymology	Etymology. amplio (Latin) = enlarged; cauda (Latin) = tail, appendage. The species name is a reference to the enlarged inferior appendages, with a prominent dorsal lobe.	en	Quinteiro, Fábio B., Costa, Anne M., Saldanha, Gabriel, Moura, Laisse, Assunção, Otávio T., Juen, Leandro (2025): A new species of Oecetis McLachlan, 1877 (Trichoptera, Leptoceridae) and new distributional records of Trichoptera in the eastern Amazon. ZooKeys 1263: 365-377, DOI: 10.3897/zookeys.1263.151613
9166155C2F0F5358B8700E788683B249.taxon	distribution	Distribution. Known only from the type locality in Pará state, Brazil (Fig. 3).	en	Quinteiro, Fábio B., Costa, Anne M., Saldanha, Gabriel, Moura, Laisse, Assunção, Otávio T., Juen, Leandro (2025): A new species of Oecetis McLachlan, 1877 (Trichoptera, Leptoceridae) and new distributional records of Trichoptera in the eastern Amazon. ZooKeys 1263: 365-377, DOI: 10.3897/zookeys.1263.151613
A51E339FD01A5F4AA19528F69F1971C0.taxon	distribution	Distribution. Brazil [new country record] (Pará), Suriname.	en	Quinteiro, Fábio B., Costa, Anne M., Saldanha, Gabriel, Moura, Laisse, Assunção, Otávio T., Juen, Leandro (2025): A new species of Oecetis McLachlan, 1877 (Trichoptera, Leptoceridae) and new distributional records of Trichoptera in the eastern Amazon. ZooKeys 1263: 365-377, DOI: 10.3897/zookeys.1263.151613
07A05E4888545C3790FBEE7F4169CF2C.taxon	distribution	Distribution. Bolivia, Brazil [new country record] (Pará), Mexico.	en	Quinteiro, Fábio B., Costa, Anne M., Saldanha, Gabriel, Moura, Laisse, Assunção, Otávio T., Juen, Leandro (2025): A new species of Oecetis McLachlan, 1877 (Trichoptera, Leptoceridae) and new distributional records of Trichoptera in the eastern Amazon. ZooKeys 1263: 365-377, DOI: 10.3897/zookeys.1263.151613
7FC6AF61DBD255DA9672071D67D29958.taxon	distribution	Distribution. Brazil [new country record] (Pará), Venezuela.	en	Quinteiro, Fábio B., Costa, Anne M., Saldanha, Gabriel, Moura, Laisse, Assunção, Otávio T., Juen, Leandro (2025): A new species of Oecetis McLachlan, 1877 (Trichoptera, Leptoceridae) and new distributional records of Trichoptera in the eastern Amazon. ZooKeys 1263: 365-377, DOI: 10.3897/zookeys.1263.151613
BE04E3438F4C5153BCDC3C801AA2793B.taxon	distribution	Distribution. Brazil (Pará, Rondônia).	en	Quinteiro, Fábio B., Costa, Anne M., Saldanha, Gabriel, Moura, Laisse, Assunção, Otávio T., Juen, Leandro (2025): A new species of Oecetis McLachlan, 1877 (Trichoptera, Leptoceridae) and new distributional records of Trichoptera in the eastern Amazon. ZooKeys 1263: 365-377, DOI: 10.3897/zookeys.1263.151613
