taxonID	type	description	language	source
C52E90E569395E37A5551C76AB307B2C.taxon	description	Figs 4, 5	en	Hrivniak, Ľuboš, Sroka, Pavel, Türkmen, Gencer, Martynov, Alexander V., Bojková, Jindřiška (2024): Integrative delimitation of a new Epeorus (Caucasiron) (Ephemeroptera, Heptageniidae) from the Caucasus with a supplement to the identification guide of Caucasian and Irano-Anatolian species. ZooKeys 1214: 265-279, DOI: 10.3897/zookeys.1214.131266
C52E90E569395E37A5551C76AB307B2C.taxon	etymology	Etymology. The species name abditus (Latin) means hidden. It refers to rare distribution and morphological similarity with related species.	en	Hrivniak, Ľuboš, Sroka, Pavel, Türkmen, Gencer, Martynov, Alexander V., Bojková, Jindřiška (2024): Integrative delimitation of a new Epeorus (Caucasiron) (Ephemeroptera, Heptageniidae) from the Caucasus with a supplement to the identification guide of Caucasian and Irano-Anatolian species. ZooKeys 1214: 265-279, DOI: 10.3897/zookeys.1214.131266
C52E90E569395E37A5551C76AB307B2C.taxon	distribution	Distribution and habitat preferences of larvae. Epeorus (Caucasiron) abditus sp. nov. has relatively wide distribution in the Caucasus region but appears to be relatively rare due to low number of specimens obtained by extensive sampling. They were found in the Pontic Mountains and the Lesser Caucasus (northeast Türkiye and southwest Georgia), and the central (Russia: Kabardino-Balkaria) and eastern (Georgia: Kakheti) parts of the Greater Caucasus (Fig. 1). The larvae were found in low abundance in cold and clear streams and rivers between 792 and 2192 m a. s. l. on stony bed substrate in turbulent flow (Fig. 3). They were not recorded in urban and agricultural areas within the region, where many localities were investigated. Larvae co-occurred with E. (C.) znojkoi, E. (C.) alpestris (Braasch, 1979), E. (C.) magnus.	en	Hrivniak, Ľuboš, Sroka, Pavel, Türkmen, Gencer, Martynov, Alexander V., Bojková, Jindřiška (2024): Integrative delimitation of a new Epeorus (Caucasiron) (Ephemeroptera, Heptageniidae) from the Caucasus with a supplement to the identification guide of Caucasian and Irano-Anatolian species. ZooKeys 1214: 265-279, DOI: 10.3897/zookeys.1214.131266
C52E90E569395E37A5551C76AB307B2C.taxon	description	Description of larva. General colouration of larvae yellowish brown with dark brown maculation. Body length of late instar larvae: ca 13.3 mm (female), 11.1 – 11.25 mm (male). Length of cerci approximately 1.2 × body length. Head. Shape oval to trapezoidal. Anterior and lateral margin rounded, posterior margin rounded in female (Fig. 4 E) and slightly rounded in male (Fig. 4 D). Head dimensions of late instar larvae: length ca 4.5 mm, width ca 3.2 mm in female; length ca 4.05 mm, width 2.75 – 2.8 mm in male. Head width / length ratio: 1.46 – 1.48 in female; 1.46 – 1.51 in male. Colouration of head: dorsal surface with pair of elongated maculae located along epicranial suture; pale stripes extending from lateral ocelli to lateral edges of head; blurred (or rectangular) macula between ocelli; rounded maculae anterolateral of lateral ocelli; blurred (or triangular) maculae near inner edges of compound eyes; pair of stripes (or scattered smaller maculae) located anteriorly from median ocellus (Fig. 4 D, E). Compound eyes grey to brownish to black. Ocelli blackish. Antennae yellowish brown, scapus and pedicellus darkened. Hair-like setae along anterior margin of head extend to lateral margins. Dorsal surface of head covered with fine hair-like setae and sparsely distributed stick-like setae. Sparse longer and fine hair-like setae located posteriorly to eyes. Mouthparts. Labrum (Fig. 5 A) widened anteriorly, with anterior margin slightly rounded or nearly straight (in dorsal view), lateral angles rounded. Dorsal surface (Fig. 5 A, left) sparsely covered with hair-like setae and short bristle-like setae; 5 – 6 longer bristle-like setae located antero-medially and two antero-laterally. Epipharynx with longer, shortly plumose bristles situated along lateral to anterior margin (Fig. 5 A, right; range of setation figured as large black dots), and brush of fine hair-like setae medially (not figured); ventral surface with group of 10 – 16 setae of various size located medio-posteriorly. Outer incisors of both mandibles with three apical teeth (Fig. 5 B, C). Inner incisor of left mandible with three apical teeth, right inner incisor bifurcated. Outer edge of both mandibular incisors with numerous setae (range of setae marked with dashed polygons). Thorax. Pronotum anteriorly narrowed, lateral edges slightly curved. Metanotum with slight postero-medial projection. Dorsal surface with dark brown maculation as on Fig. 4 A and covered with fine, hair-like setae (as on abdominal terga and head); sparse longer, hair-like setae along pro-, meso- and metanotal suture. Legs. Colour pattern of femora as on Fig. 4 F. Femora without medial hypodermal spot. Femora apically slightly darkened; patella-tibial suture darkened; tarsi proximally and distally darkened. Dorsal surface of femora covered by short (sporadically elongated) apically rounded spatulate setae (Fig. 5 D). Dorsal margin of tibiae and tarsi with row of long setae; ventral margin of both with short distally accumulated spine-like setae. Tarsal claws with 3 – 4 denticles. Abdominal terga. Colour pattern of abdominal terga consists of transversal stripe along anterior margin of terga I – IX, medially extending to: i) large median triangular macula on terga II – III (IV), and ii) triangular or T-shaped macula on terga V – IX (medial macula on tergum VIII and IX often widened). Median macula on terga V – VII surrounded by pale area (Fig. 4 G). Tergum X without distinct maculation. Lateral margin of terga I – IX with oblique macula. Denticles along posterior margin on terga strongly sclerotised, irregular and pointed (Fig. 5 E). Surface of terga covered with hair-like setae and sparsely with stick-like setae. Tergum X with short postero-lateral projections (Fig. 5 J, K). Longitudinal medial row of hair-like setae along abdominal terga present. Abdominal sterna. Yellowish, with colouration pattern on sterna I – VIII consisting of rounded median macula (Fig. 4 H, arrow). In more pigmented specimens, median macula with paired pale spots located medio-posteriorly. Rounded median macula often poorly expressed and only medio-posterior edge of sterna is slightly pigmented (Fig. 4 I, arrow). Colouration pattern sporadically restricted to sterna I and II or absent. Sternum IX of female with V-shaped median emargination and surface covered by setae centrally (Fig. 5 L). Gills. Dorsal surface of gill plate I yellowish; of gill plates II – VII greyish on anterior half, brownish on posterior half. Ventral margin of all gill plates yellowish. Costal projection on gill plate III well-developed (Fig. 5 G, arrow). Gill plate VII wide (in natural position of ventral view; Figs 4 J, 5 H, I). Cerci. Yellowish brown, basally darkened.	en	Hrivniak, Ľuboš, Sroka, Pavel, Türkmen, Gencer, Martynov, Alexander V., Bojková, Jindřiška (2024): Integrative delimitation of a new Epeorus (Caucasiron) (Ephemeroptera, Heptageniidae) from the Caucasus with a supplement to the identification guide of Caucasian and Irano-Anatolian species. ZooKeys 1214: 265-279, DOI: 10.3897/zookeys.1214.131266
