taxonID	type	description	language	source
BBD01E0400F05F0FAAC57955AC81217F.taxon	description	Figs 13, 14	en	Hrivniak, Ľuboš, Sroka, Pavel, Godunko, Roman J., Martynov, Alexander V., Palatov, Dmitry M., Bojková, Jindřiška (2025): Discovering diversity of Central Asian and Himalayan Epeorus (Caucasiron) mayflies (Ephemeroptera, Heptageniidae) using DNA barcoding and morphology. ZooKeys 1234: 89-125, DOI: 10.3897/zookeys.1234.141196
BBD01E0400F05F0FAAC57955AC81217F.taxon	distribution	Distribution, habitat, and biology. Tian Shan: Kazakhstan (Braasch and Soldán 1979; Kluge 2015), Kyrgyzstan; Pamir: Tajikistan (Kluge 2015) (Fig. 1). The species inhabits mountain streams with rapid turbulent flow and bed substrate formed by stones and boulders (Kluge 2015). The altitude of our sampling sites ranged between 1717 and 2135 m a. s. l. Adults were recorded from May to September (Kluge 2015).	en	Hrivniak, Ľuboš, Sroka, Pavel, Godunko, Roman J., Martynov, Alexander V., Palatov, Dmitry M., Bojková, Jindřiška (2025): Discovering diversity of Central Asian and Himalayan Epeorus (Caucasiron) mayflies (Ephemeroptera, Heptageniidae) using DNA barcoding and morphology. ZooKeys 1234: 89-125, DOI: 10.3897/zookeys.1234.141196
691B9F9C6D9B5720A5740E797BF2EC19.taxon	description	Figs 3, 4, 5, 6	en	Hrivniak, Ľuboš, Sroka, Pavel, Godunko, Roman J., Martynov, Alexander V., Palatov, Dmitry M., Bojková, Jindřiška (2025): Discovering diversity of Central Asian and Himalayan Epeorus (Caucasiron) mayflies (Ephemeroptera, Heptageniidae) using DNA barcoding and morphology. ZooKeys 1234: 89-125, DOI: 10.3897/zookeys.1234.141196
691B9F9C6D9B5720A5740E797BF2EC19.taxon	etymology	Etymology. The species name himalayensis (Latin) refers to the distribution in the Himalayas.	en	Hrivniak, Ľuboš, Sroka, Pavel, Godunko, Roman J., Martynov, Alexander V., Palatov, Dmitry M., Bojková, Jindřiška (2025): Discovering diversity of Central Asian and Himalayan Epeorus (Caucasiron) mayflies (Ephemeroptera, Heptageniidae) using DNA barcoding and morphology. ZooKeys 1234: 89-125, DOI: 10.3897/zookeys.1234.141196
691B9F9C6D9B5720A5740E797BF2EC19.taxon	description	Description of larva. General coloration yellowish brown with dark brown maculation (Fig. 3). Body length (BL) of late-instar larvae: 15.0 mm (female; n = 1), 11.8 – 13.1 mm (male; n = 3). Length of cerci approximately 1.2 × body length. Head. Shape trapezoidal, slightly rounded (Fig. 3 D, E). Head dimensions of late-instar larvae: length 3.3 mm, width 5.0 mm in female; length 2.5 – 2.6 mm, width 4.0 – 4.1 mm in male. Width / length ratio: 1.48 – 1.57 (female; n = 8), 1.48 – 1.64 (male; n = 8). Coloration pattern of dorsal surface consists of: i) paired stripe-like and rounded maculae along epicranial suture, ii) pair of triangular (or blurred) macula near inner edges of eyes, iii) pair of rounded maculae ventrally to lateral ocelli, iv) pale stripes extending from lateral ocelli to lateral edges of head, v) rectangular macula between ocelli, vi) stripe-like and rounded maculae ventrally to median ocellus. Antennae yellowish brown, scapus and pedicellus darkened (Fig. 3 D, E). Dorsal surface covered with short rounded spatulate setae (as on abdominal terga; Fig. 4 E), fine hair-like setae and stick-like setae. Sparse longer and fine hair-like setae located posteriorly to eyes. Mouthparts. Labrum (Fig. 4 A) widened anteriorly; anterior margin slightly rounded or nearly straight. Lateral angles rounded. Dorsal surface covered with setae of different size, 4 – 6 longer bristle-like setae located antero-medially and two bristles antero-laterally (Fig. 4 A, left half). Epipharynx with longer, slightly plumose bristles situated along lateral to anterior margin, cluster of fine, hair-like setae medially (not figured), and group of 6 – 12 setae of various size (Fig. 4 A, right half). Outer incisors of both mandibles with three apical teeth; outer tooth blunt in both mandibles. Inner incisor of left mandible with three apical teeth (Fig. 4 B), right inner incisor bifurcated (Fig. 4 C). Thorax. Prothorax anteriorly narrowed, lateral edges slightly rounded. Metanotum with small blunt posterior-median projection. Dorsal surface covered with hair-like setae, stick-like setae and short rounded spatulate setae (as on abdominal terga and head). Sparse longer, hair-like setae along pro-, meso- and metanotal suture. Legs. Coloration on Fig. 3 H, I. Femora with median hypodermal spot, often transversely extended. Base and apex of femora darkened; patella-tibial suture darkened; tarsi proximally and distally darkened. Dorsal surface of femora covered by short rounded spatulate setae (Fig. 4 D), hair-like setae and sparsely distributed stick-like setae. Dorsal edge of femora with blade-like setae. Dorsal margin of tibiae and tarsi with row of dense hair-like setae; ventral margin with irregular row of distally accumulated spines. Tarsal claws with two or three denticles. Abdominal terga. Color pattern of abdominal terga consists of transversal stripe along anterior margin of terga I – IX (X), medially extending to: i) triangular or blurred macula on terga II – IV and ii) triangular or T-shaped macula on terga V – IX (median macula on terga VIII and IX widened) (Fig. 3 F, G). Pair of short stripes or spots present antero-laterally to median maculae. Lateral margins with oblique stripe-like maculae on terga I – IX (often dorso-posteriorly extended). Denticles along posterior margin of terga dense, irregular, and pointed (Fig. 4 F). Surface of terga covered with hair-like setae, stick-like setae and rounded spatulate setae (Fig. 4 E, F). Tergum X with short posterolateral projections (Fig. 4 L, arrow). Terga with longitudinal median row of hair-like setae. More or less developed posteromedian spine (best expressed on terga VII – IX as on Fig. 11 M, N) were observed in larvae of BL 6.0 – 8.2 mm (barcoded specimens SP 12, SP 13, SP 22). Tergal spines were not observed in late instar larvae and last instar larval exuvia from reared adults (barcoded specimens: IN 1, IN 7, IN 8, IN 9). Abdominal sterna. Yellowish, with a pattern consisting of more or less defined triangular maculae (Fig. 3 K – N). Nerve ganglia darkened. Sternum IX of female with V-shaped median emargination and numerous hair-like setae (Fig. 4 M). Gills. Dorsal surface of gill plate I yellowish and of gill plates II – VII greyish on anterior half, brownish on posterior half. Ventral margin of all gill plates yellowish brown, sometimes pinkish. Projection on gill plate III well developed (Fig. 4 H, arrow). Gill plate VII narrow (in natural position of ventral view, Figs 3 J, 4 J). Dorsal margin of gill plates IV – VII with more or less developed papillae; best expressed on gill plates VI – VII (Fig. 4 I). Cerci. Yellowish brown, basally darkened.	en	Hrivniak, Ľuboš, Sroka, Pavel, Godunko, Roman J., Martynov, Alexander V., Palatov, Dmitry M., Bojková, Jindřiška (2025): Discovering diversity of Central Asian and Himalayan Epeorus (Caucasiron) mayflies (Ephemeroptera, Heptageniidae) using DNA barcoding and morphology. ZooKeys 1234: 89-125, DOI: 10.3897/zookeys.1234.141196
691B9F9C6D9B5720A5740E797BF2EC19.taxon	description	Description of male imago. General coloration yellowish brown with dark brown maculation (Fig. 5 A). Body length 11.5 – 13.0 mm (n = 2); length of cerci approximately 2 × body length. Length of fore wings 14.0 – 15.3 mm, hind wings 4.5 – 5.1 mm. Head. Frons yellowish brown; frontal fold dark brown. Antennae yellowish; scapus and pedicellus darkened. Ocelli basally blackish, apically whitish. Compound eyes greyish brown, basally darkened (Fig. 5 B, C). Compound eyes not touching each other (distance between eyes 0.10 – 0.66 of median ocellus; n = 3) or touching each other (n = 1). Thorax. Pronotum dark brown; meso- and metathorax yellowish brown with dark brown maculation. Dorsal surface of mesothorax yellowish brown, median longitudinal suture darkened. Mesothoratic fucasternum yellowish brown to brown. Metathorax with blunt posteromedian projection. Wing membrane colorless. Veins dark brown, basally paler. Pterostigmatic area cloudy, with simple cross veins. Costal brace dark brown (Fig. 5 A). Hind wings with short triangular costal projection. Femora basally and apically darkened, median spot present. Tibiae basally darkened; claws dark brown (Fig. 5 A, G). Fore legs darker than middle and hind legs. One claw blunt, one claw pointed. Abdomen. Color pattern of abdominal terga as described in larva. Tergum X with median macula (Fig. 5 D). Lateral margins with oblique stripe-like maculae on terga I – IX extending dorso-posteriorly, forming transversal stripe-like macula along posterior margin of terga (Fig. 5 D, E). Abdominal sterna with narrow triangular maculae (Fig. 5 F). Styliger yellowish brown; medially slightly convex and sparsely covered by hair-like setae (Fig. 5 H, J). Forceps brown or yellowish, apically paler. Penis lobes brown and basally paler or yellowish, with shallow medio-apical notch (Fig. 5 H, J, arrow), and short spine-like setae on interior edges. Titillators well developed and apically serrated (Fig. 5 H, I). Titillators reach 0.30 – 0.44 of respective penis lobe length. Cerci. Yellowish, basally darkened.	en	Hrivniak, Ľuboš, Sroka, Pavel, Godunko, Roman J., Martynov, Alexander V., Palatov, Dmitry M., Bojková, Jindřiška (2025): Discovering diversity of Central Asian and Himalayan Epeorus (Caucasiron) mayflies (Ephemeroptera, Heptageniidae) using DNA barcoding and morphology. ZooKeys 1234: 89-125, DOI: 10.3897/zookeys.1234.141196
691B9F9C6D9B5720A5740E797BF2EC19.taxon	description	Description of female imago. General coloration yellowish brown with dark brown maculation (Fig. 6 A). Body length 13.0 – 15.5 mm (n = 2); length of cerci 2.3 × body length. Length of fore wings 18.2 – 19.5 mm, hind wings 5.6 – 6.3 mm. Head. Frons yellowish brown; frontal fold brownish. Antennae yellowish; scapus and pedicellus darkened. Ocelli basally blackish, apically whitish. Eyes greyish (Fig. 6 B, C). Thorax. Coloration as described in male imago. Wing membrane colorless (area around bullae sometimes darkened; Fig. 6 A). Veins dark brown, basally paler. Pterostigmatic area cloudy, with mostly simple cross veins. Costal brace dark brown. Hind wings with short triangular costal projection. Coloration of legs as in male imago. Abdomen. Coloration pattern of abdominal terga and sterna as in male imago (Fig. 6 D – F). Subgenital plate apically narrowed, posterior margin rounded or slightly concave (Fig. 6 G – I). Subanal plate with shallow U-shaped median emargination.	en	Hrivniak, Ľuboš, Sroka, Pavel, Godunko, Roman J., Martynov, Alexander V., Palatov, Dmitry M., Bojková, Jindřiška (2025): Discovering diversity of Central Asian and Himalayan Epeorus (Caucasiron) mayflies (Ephemeroptera, Heptageniidae) using DNA barcoding and morphology. ZooKeys 1234: 89-125, DOI: 10.3897/zookeys.1234.141196
691B9F9C6D9B5720A5740E797BF2EC19.taxon	description	Description of eggs. Oval shaped, dimensions approximately 188 × 101 μm (average values from 6 eggs). Chorionic surface slightly granulated (Fig. 6 K), without distinct structures. One or two visible micropyle, shallow and rounded, located in subequatorial position (~ 12.5 μm in width) (Fig. 6 J, K).	en	Hrivniak, Ľuboš, Sroka, Pavel, Godunko, Roman J., Martynov, Alexander V., Palatov, Dmitry M., Bojková, Jindřiška (2025): Discovering diversity of Central Asian and Himalayan Epeorus (Caucasiron) mayflies (Ephemeroptera, Heptageniidae) using DNA barcoding and morphology. ZooKeys 1234: 89-125, DOI: 10.3897/zookeys.1234.141196
98D3F3C8D9755D23BBCCE07E72D7E3F0.taxon	description	Figs 7, 8, 9	en	Hrivniak, Ľuboš, Sroka, Pavel, Godunko, Roman J., Martynov, Alexander V., Palatov, Dmitry M., Bojková, Jindřiška (2025): Discovering diversity of Central Asian and Himalayan Epeorus (Caucasiron) mayflies (Ephemeroptera, Heptageniidae) using DNA barcoding and morphology. ZooKeys 1234: 89-125, DOI: 10.3897/zookeys.1234.141196
98D3F3C8D9755D23BBCCE07E72D7E3F0.taxon	etymology	Etymology. The species name lanceolatus (Latin) refers to lanceolate setae on abdominal terga and dorsal surface of femora characteristic for larvae.	en	Hrivniak, Ľuboš, Sroka, Pavel, Godunko, Roman J., Martynov, Alexander V., Palatov, Dmitry M., Bojková, Jindřiška (2025): Discovering diversity of Central Asian and Himalayan Epeorus (Caucasiron) mayflies (Ephemeroptera, Heptageniidae) using DNA barcoding and morphology. ZooKeys 1234: 89-125, DOI: 10.3897/zookeys.1234.141196
98D3F3C8D9755D23BBCCE07E72D7E3F0.taxon	description	Description of larva. General coloration yellowish brown with dark brown to blackish maculation (Fig. 7). BL of late-instar larva 13.87 mm (female; n = 1); male unknown. Length of cerci unknown. Head. Shape oval to trapezoidal (Fig. 7 A). Head dimensions of late-instar larva: length 3.5 mm, width 5.7 mm (female; n = 1), male unknown. Head width / length ratio: 1.53 (female; n = 1), male unknown. Coloration pattern of dorsal surface consists of: i) paired stripe-like and rounded maculae along epicranial suture, ii) pair of triangular (or blurred) maculae near inner edges of eyes, iii) pair of rounded maculae ventrally to lateral ocelli, iv) pale stripes extending from lateral ocelli to lateral edges of head, v) blurred or rectangular maculae between ocelli, vi) scattered maculae ventrally to median ocellus. Antennae yellowish brown, scapus and pedicellus darkened. Dorsal surface of head densely covered with elongated lanceolate setae (as on abdominal terga; Fig. 8 E, F), fine hair-like setae and stick-like setae. Sparse longer and fine hair-like setae located posteriorly to eyes. Mouthparts. Labrum (Fig. 8 A) widened anteriorly; anterior margin slightly rounded or straight. Lateral angles rounded. Dorsal surface sparsely covered with setae of different size, five or six longer bristle-like setae located antero-medially, and two bristles antero-laterally (Fig. 8 A, left half). Epipharynx with longer, slightly plumose bristles situated along lateral to anterior margin, cluster of fine, hair-like setae medially (not figured), and group of 4 – 6 setae of various size (Fig. 8 A, right half). Outer incisors of both mandibles with three apical teeth; outer tooth blunt in both mandibles. Inner incisor of left mandible with three apical teeth (Fig. 8 B), right inner incisor bifurcated (Fig. 8 C). Thorax. Prothorax anteriorly narrowed, lateral edges slightly rounded. Metanotum with small blunt posteromedian projection. Dorsal surface covered with hair-like setae, stick-like setae, and lanceolate setae (as on abdominal terga and head, Fig. 8 E, F); sparse longer, hair-like setae along pro-, meso- and metanotal suture. Legs. Coloration on Fig. 7 B. Femora with medial hypodermal spot, often transversely extended. Base and apex of femora darkened; patella-tibial suture darkened; tarsi proximally and distally darkened. Dorsal surface of femora covered by lanceolate setae, hair-like setae, and sparsely distributed stick-like setae (Fig. 8 E; drawn from late-instar larvae and last instar larval exuvium). Dorsal edge of femora with blade-like setae. Dorsal margin of tibiae and tarsi with row of dense hair-like setae; ventral margin with irregular row of distally accumulated spines. Tarsal claws with 3 – 4 denticles. Abdominal terga. Colour pattern of abdominal terga consists of transversal stripe along anterior margin of terga I – IX (X) medially extending to: i) triangular macula on terga II – IV, ii) T-shaped macula on terga V – VI (VII), and iii) triangular macula on terga (VII) VIII – IX (Fig. 7 C). Pair of short stripes sometimes present antero-laterally to median macula. Lateral margins with oblique stripe-like maculae on terga I – IX. Denticles along posterior margin on terga dense, relatively narrow, irregular, and pointed (Fig. 8 F). Surface of terga covered with hair-like setae, stick-like setae, and lanceolate (sporadically narrow spatulate) setae (Fig. 8 E, F; drawn from late-instar larvae and last instar larval exuvium). Tergum X with well-developed posterolateral projections (Fig. 8 L, M, arrow). Terga with longitudinal median row of hair-like setae. Tergal spines not observed in late-instar larvae and larval exuvium from reared adult. Abdominal sterna. Yellowish, with fine oblique stripes (slightly curved in late-instar larvae; Fig. 7 E, F). Nerve ganglia darkened. Sternum IX of female with V-shaped median emargination and numerous hair-like setae (Fig. 8 N). Gills. Dorsal surface of gill plate I yellowish; of gill plates II – VII brownish on anterior half, greyish to brownish on posterior half. Ventral margin of all gill plates yellowish. Projection of gill plate III well developed (Fig. 8 H, arrow). Gill plate VII narrow (in natural position of ventral view, Figs 7 D, 8 K). Dorsal margin of gill plates IV – VII with more or less developed papillae; best expressed on gill plates VI and VII (Fig. 8 I). Cerci. Yellowish brown, basally darkened.	en	Hrivniak, Ľuboš, Sroka, Pavel, Godunko, Roman J., Martynov, Alexander V., Palatov, Dmitry M., Bojková, Jindřiška (2025): Discovering diversity of Central Asian and Himalayan Epeorus (Caucasiron) mayflies (Ephemeroptera, Heptageniidae) using DNA barcoding and morphology. ZooKeys 1234: 89-125, DOI: 10.3897/zookeys.1234.141196
98D3F3C8D9755D23BBCCE07E72D7E3F0.taxon	description	Description of female imago. General coloration yellowish brown with dark brown to blackish maculation (Fig. 9 A – F). Body length 14.0 mm (n = 1); length of cerci unknown. Length of fore wings 17.5 mm, length of hind wings unknown (broken). Head. Frons brownish; frontal fold dark brown (Fig. 9 B, C). Antennae yellowish brown; scapus and pedicellus darkened. Eyes greyish, ocelli basally blackish, apically whitish. Thorax. Prothorax dark brown. Mesothorax yellowish brown; median longitudinal suture darkened. Metathorax with short posterior-median blunt projection. Furcasternum dark brown. Wing membrane of fore wings in subimago cloudy, cross veins darkened (Fig. 9 A); hind wings unknown. Femora apically and basally darkened; median spot present (Fig. 9 G). Tibiae apically and basally darkened, tarsi brownish. One claw blunt, one claw pointed. Abdomen. Coloration pattern of abdominal terga similar as in late-instar larvae (Fig. 9 D – F). Tergum X with medial macula. Lateral margins with oblique stripe-like maculae on terga I – IX extending dorso-posteriorly, forming transversal stripe-like macula along posterior margin of terga (Fig. 9 D, E). Abdominal sterna with fine, slightly curved oblique stripes (Fig. 9 F). Nerve ganglia darkened. Subgenital plate posteriorly narrowed, posterior margin slightly rounded. Subanal plate posteriorly narrowed; posterior margin straight (Fig. 9 I). Cerci. Unknown.	en	Hrivniak, Ľuboš, Sroka, Pavel, Godunko, Roman J., Martynov, Alexander V., Palatov, Dmitry M., Bojková, Jindřiška (2025): Discovering diversity of Central Asian and Himalayan Epeorus (Caucasiron) mayflies (Ephemeroptera, Heptageniidae) using DNA barcoding and morphology. ZooKeys 1234: 89-125, DOI: 10.3897/zookeys.1234.141196
98D3F3C8D9755D23BBCCE07E72D7E3F0.taxon	description	Description of eggs. Oval shaped, dimensions approximately 186 × 110 μm (average values from 7 eggs). Chorionic surface with texture as on Fig. 9 L. One to three visible micropyle shallow and rounded, located in subequatorial position (~ 12.5 μm in width) (Fig. 9 J, K). Male imago. Unknown.	en	Hrivniak, Ľuboš, Sroka, Pavel, Godunko, Roman J., Martynov, Alexander V., Palatov, Dmitry M., Bojková, Jindřiška (2025): Discovering diversity of Central Asian and Himalayan Epeorus (Caucasiron) mayflies (Ephemeroptera, Heptageniidae) using DNA barcoding and morphology. ZooKeys 1234: 89-125, DOI: 10.3897/zookeys.1234.141196
FC5293A0C6C857C3A1CDA74F77CA2AF9.taxon	description	Figs 10, 11	en	Hrivniak, Ľuboš, Sroka, Pavel, Godunko, Roman J., Martynov, Alexander V., Palatov, Dmitry M., Bojková, Jindřiška (2025): Discovering diversity of Central Asian and Himalayan Epeorus (Caucasiron) mayflies (Ephemeroptera, Heptageniidae) using DNA barcoding and morphology. ZooKeys 1234: 89-125, DOI: 10.3897/zookeys.1234.141196
FC5293A0C6C857C3A1CDA74F77CA2AF9.taxon	etymology	Etymology. The species name lineatus (Latin) refers to a median line on abdominal sterna characteristic for larvae.	en	Hrivniak, Ľuboš, Sroka, Pavel, Godunko, Roman J., Martynov, Alexander V., Palatov, Dmitry M., Bojková, Jindřiška (2025): Discovering diversity of Central Asian and Himalayan Epeorus (Caucasiron) mayflies (Ephemeroptera, Heptageniidae) using DNA barcoding and morphology. ZooKeys 1234: 89-125, DOI: 10.3897/zookeys.1234.141196
FC5293A0C6C857C3A1CDA74F77CA2AF9.taxon	description	Description of larva. General coloration yellowish brown with dark brown to blackish maculation (Fig. 10). Body length of late-instar larva unknown. Maximum body length of examined larvae 14.0 mm (female), 9.30 mm (male). Length of cerci ~ 1.2 × body length. Head. Shape trapezoidal (Fig. 10 D, E). Head width / length ratio: 1.49 – 1.56 (female; n = 6), 1.50 – 1.57 (male; n = 2). Coloration pattern of dorsal surface consists of: i) paired stripe-like and rounded maculae along epicranial suture, ii) pair of triangular (or blurred) maculae near inner edges of eyes, iii) pair of rounded maculae ventrally to lateral ocelli, iv) pale stripes extending from lateral ocelli to lateral edges of head, v) rectangular or blurred macula between ocelli, vi) scattered smaller maculae ventrally to median ocellus. Antennae yellowish brown, scapus and pedicellus darkened. Dorsal surface covered with elongated spatulate setae (as on abdominal terga; Fig. 11 E), fine hair-like setae and stick-like setae. Sparse longer and fine hair-like setae located posteriorly to eyes. Mouthparts. Labrum (Fig. 11 A) widened anteriorly; anterior margin slightly rounded or nearly straight. Lateral angles rounded. Dorsal surface sparsely covered with setae of different size, 5 – 6 longer bristle-like setae located antero-medially, and two bristles antero-laterally (Fig. 11 A, left half). Epipharynx with longer, slightly plumose bristles situated along lateral to anterior margin, cluster of fine hair-like setae medially (not figured), and 5 – 9 setae of various size (Fig. 11 A, right half). Outer incisors of both mandibles with three apical teeth; outer tooth blunt in both mandibles. Inner incisor of left mandible with three apical teeth (Fig. 11 B), right inner incisor bifurcated (Fig. 11 C). Thorax. Prothorax anteriorly narrowed, lateral edges slightly rounded. Metanotum with small blunt posteromedian projection. Dorsal surface covered with hair-like setae, stick-like setae and elongated spatulate setae (as on abdominal terga and head); sparse longer, hair-like setae along pro-, meso-, and metanotal suture. Legs. Coloration as on Fig. 10 F. Femora with medial hypodermal spot, often transversely extended. Base and apex of femora darkened; patella-tibial suture darkened; tarsi proximally and distally darkened. Dorsal surface of femora covered by rounded (sporadically apically narrowed) spatulate setae (Fig. 11 D), hair-like setae, and sparsely distributed stick-like setae. Dorsal edge of femora with blade-like setae. Dorsal margin of tibiae and tarsi with row of dense hair-like setae; ventral margin with irregular row of distally accumulated spines. Tarsal claws with 2 – 3 denticles. Abdominal terga. Colour pattern of abdominal terga consists of transversal stripe along anterior margin of terga I – IX (X) medially extending to: i) triangular, rounded, or anteriorly and posteriorly widened macula on terga II – IV; and ii) triangular or T-shaped macula on terga V – IX (Fig. 10 I – M). Lateral margins with oblique stripe-like maculae on terga I – IX, sometimes dorso-posteriorly extended. Denticles along posterior margin on terga dense, irregular, and pointed (Fig. 11 F). Surface of terga covered with hair-like setae, stick-like setae, and elongated (sporadically rounded) spatulate setae (Fig. 11 E, F) (dominantly rounded spatulate setae can be present in younger instars). Tergum X with well-developed posterolateral projections (Fig. 11 L, arrow). Terga with longitudinal median row of hair-like setae. More or less developed posteromedian spine (most expressed on terga VII – IX (Fig. 11 M, N). Posteromedian tergal spine observed only in larvae of BL 4.6 – 11.2 mm (n = 22; barcoded specimens SP 21, SP 31, L 39, SP 23, IN 5), not observed in larger larvae of BL 11.2 – 14.0 (n = 5; barcoded specimens: GU 2, SP 32). Abdominal sterna. Yellowish, with a pattern consisting of oblique stripes and median line extending from anterior to posterior margin (Fig. 10 N – Q). Median line often posteriorly widened (Fig. 11 N) or reduced to posteromedian macula Fig. 11 P, Q, arrows). Sternum IX of female apically narrowed, with V-shaped median emargination, and numerous hair-like setae (Fig. 11 O). Gills. Dorsal surface of gill plate I yellowish; of gill plates II – VII brownish. Ventral margin of all gill plates yellowish. Projection of gill plate III well-developed (Fig. 11 H, arrow). Gill plate VII wide (in natural position of ventral view, Figs 10 G, H, 11 K). Dorsal margin of gill plates (III) IV – VII with more or less developed papillae; best expressed on gill plates VI and VII (Fig. 11 I). Cerci. Yellowish brown, basally darkened.	en	Hrivniak, Ľuboš, Sroka, Pavel, Godunko, Roman J., Martynov, Alexander V., Palatov, Dmitry M., Bojková, Jindřiška (2025): Discovering diversity of Central Asian and Himalayan Epeorus (Caucasiron) mayflies (Ephemeroptera, Heptageniidae) using DNA barcoding and morphology. ZooKeys 1234: 89-125, DOI: 10.3897/zookeys.1234.141196
C44E9428B608507EB0A88C493969FF85.taxon	description	Figs 15, 16	en	Hrivniak, Ľuboš, Sroka, Pavel, Godunko, Roman J., Martynov, Alexander V., Palatov, Dmitry M., Bojková, Jindřiška (2025): Discovering diversity of Central Asian and Himalayan Epeorus (Caucasiron) mayflies (Ephemeroptera, Heptageniidae) using DNA barcoding and morphology. ZooKeys 1234: 89-125, DOI: 10.3897/zookeys.1234.141196
C44E9428B608507EB0A88C493969FF85.taxon	distribution	Distribution, habitat, and biology. Himalayas: Nepal and India (Fig. 1). The species inhabits rhithral zones of mountain streams. The altitude of the sampling sites ranged between 2000 and 2400 m a. s. l. Late-instar larvae were recorded in May (Braasch 2006 a).	en	Hrivniak, Ľuboš, Sroka, Pavel, Godunko, Roman J., Martynov, Alexander V., Palatov, Dmitry M., Bojková, Jindřiška (2025): Discovering diversity of Central Asian and Himalayan Epeorus (Caucasiron) mayflies (Ephemeroptera, Heptageniidae) using DNA barcoding and morphology. ZooKeys 1234: 89-125, DOI: 10.3897/zookeys.1234.141196
8339538B878F522FB270B9D2A9E0B11F.taxon	description	Figs 17, 18	en	Hrivniak, Ľuboš, Sroka, Pavel, Godunko, Roman J., Martynov, Alexander V., Palatov, Dmitry M., Bojková, Jindřiška (2025): Discovering diversity of Central Asian and Himalayan Epeorus (Caucasiron) mayflies (Ephemeroptera, Heptageniidae) using DNA barcoding and morphology. ZooKeys 1234: 89-125, DOI: 10.3897/zookeys.1234.141196
8339538B878F522FB270B9D2A9E0B11F.taxon	distribution	Distribution, habitat, and biology. Himalayas: India (Eaton 1883 – 1888; Vasanth et al. 2021), Nepal (Braasch 1980 b, 1981), south-east Tibet (Ma and Zhou 2022); Hengduan Shan and Yunnan-Guizhou Plateau: China (Ma and Zhou 2022) (Fig. 1). The species inhabits mountain streams and rivers in relatively wide altitudinal range. The altitude of the sampling sites ranged between 488 and 2100 m a. s. l. (our data; Braasch 1980 b, 1981; Vasanth et al. 2021). Adults were recorded in May (Braasch 1980 b).	en	Hrivniak, Ľuboš, Sroka, Pavel, Godunko, Roman J., Martynov, Alexander V., Palatov, Dmitry M., Bojková, Jindřiška (2025): Discovering diversity of Central Asian and Himalayan Epeorus (Caucasiron) mayflies (Ephemeroptera, Heptageniidae) using DNA barcoding and morphology. ZooKeys 1234: 89-125, DOI: 10.3897/zookeys.1234.141196
