Epeorus (Caucasiron) bicolliculatus Hrivniak, 2017

Hrivniak, Ľubos, Sroka, Pavel, Bojkova, Jindriska & Godunko, Roman J., 2020, Identification guide to larvae of Caucasian Epeorus (Caucasiron) (Ephemeroptera, Heptageniidae), ZooKeys 986, pp. 1-53 : 1

Epeorus (Caucasiron) bicolliculatus Hrivniak, 2017 Figs 33 , 34 , 35

Epeorus alpicola (Eaton, 1871); in Türkmen and Kazancı (2015), partim

Epeorus sylvicola (Pictet, 1865); in Türkmen and Kazancı (2015), partim

Epeorus (Caucasiron) sp.; in Martynov et al. (2016)

Type locality.

Georgia, Autonomous Republic of Adjara, vicinity of Chakhati village, Kintrishi River; 41°45'43"N / 41°58'34"E; 325 m a.s.l.

Distribution.

Georgia, north-eastern Turkey, Armenia, south-western Russia (Fig. 33 ).

Habitat.

Larvae inhabit streams and rivers of different sizes, from to middle-sized rivers at low altitude to small streams at high altitudes. Altitudinal range of sampling sites 40-1804 m a.s.l. (Fig. 33 ).

Main morphological diagnostics of larvae.

(i) abdominal terga II-IX with paired postero-medial protuberances (Fig. 34H , arrows); (ii) abdominal terga V-VII with stripe-like medial macula, often anteriorly and posteriorly widened, and with antero-lateral stripes (Fig. 34G, H ); (iii) abdominal sterna as on Fig. 34B, J-L ; (iv) setae on abdominal terga wide at base (Fig. 35E ); (v) gill plates VII (in natural position from ventral view) narrow (Figs 34I , 35I, J ); (vi) femora without medial hypodermal spot (Fig. 34F , blurred macula may be present in darker specimens); (vii) tergum X without postero-lateral projections (Fig. 35H ); (viii) gill plates III with well-developed projection (Fig. 35G ).

Remarks.

Taxonomy. This species was described based on the larva, male subimago and imago (associated by rearing), female imago (associated by DNA analysis) and eggs. Material was collected from the western Lesser Caucasus ( Hrivniak et al. 2017). The type series is currently deposited in IECA.

Figures

Figure 33. Geographical (left) and vertical (right) distribution of Epeorus (Caucasiron) bicolliculatus.

Figure 34. Epeorus (Caucasiron) bicolliculatus, larva: A habitus in dorsal view B habitus in ventral view C habitus in lateral view D head of male in dorsal view E head of female in dorsal view F middle leg in dorsal view G abdominal terga H abdominal terga VI-X (arrows point on postero-medial protuberances) I gills VII (in natural position from ventral view) J-L abdominal sterna II-VI.

Figure 35. Epeorus (Caucasiron) bicolliculatus, larva: A labrum (left half in dorsal view right half in ventral view) B incisors of left mandible C incisors of right mandible D setae on dorsal surface of femora E surface and posterior margin of abdominal tergum VII with detail of basally wide setae F gill I G gill III H abdominal segments VIII-X in lateral view I gill VII (flattened on slide) J gill VII (in natural position from ventral view) K sternum IX of female with observed variability.