Genus Regulaneuria Zhou (in Lei, Gong, Zhang & Zhou), 2021

Genus Regulaneuria Zhou (in Lei et al.) 2021: 2 (imagos, subimagos, nymph, egg).

Type species: Regulaneuria cingulata (Navás, 1933)

Diagnosis. Male imago. Compound eyes not contiguous, widely separated by a distance 2.5-3.0 times frontal ocellus width (Fig. 2A). Number of crossveins on forewing reduced (less than 18 in costal and subcostal fields), most crossveins obviously pigmented; almost all crossveins of forewing, except those in costal and subcostal fields and wing base, regularly or roughly arranged into 5 – 6 rows (Figs 2D, 7A – D); hindwing with brown pigmentation along outer margin at distal half (Fig. 2D). First tarsal segment of foreleg 0.7 – 0.8 times second one length; midtarsus longer than midtibia (Fig. 2C). Styliger convex medially and with a pair of sublateral projections (Fig. 3E); penes almost totally fused with median titillators (Figs 3E – F).

Female imago. Subgenital plate greatly elongated posteriorly reaching the posterior margin of sternum VIII; subanal plate tongue-shape, elongated and narrowed (Fig. 3G).

Nymph. Pronotum expanded laterally, wider than head. Labrum not or slightly expanded laterally with round apex (Figs 5B, C); superlingua curved with relatively sharpened tip (Fig. 5F); maxillae with two distal dentisetae (proximal one bifurcated) and one proximal dentiseta (bifurcated, with one branch fringed) (Figs 5H, 8G). Supracoxal spurs present but rounded or bluntly developed (Fig. 6B). Bristles on upper faces of femora with more or less truncated apex; hindleg with pinnate (lateral margins serrated) bristles on inner surface of tibia and tarsus (Figs 8A – F). Lamellae of tergalius I with anal margin extended; tergalius VII with basal half convex and apical half narrowed (Fig. 6E). Caudalii with whorls of spine-like setae on each segment, primary swimming setae lost (Fig. 6F).

Egg. Ovoid; chorion irregularly covered by small KCTs on whole surface; micropyle with single margin (Figs 8H, I).

Species composition. Regulaneuria chongchongae sp. nov.: Hainan Province, China Regulaneuria cingulata: Zhejiang Province, China

Discussion. Regulaneuria can be easily distinguished from all other Ecdyonurinae genera by the combination of the following characters: in the imaginal stage, A) compound eyes not contiguous and widely separated by a distance 2.5 – 3.0 times frontal ocellus width; B) most crossveins on forewing, except those in costal and subcostal fields and wing base, regularly or roughly arranged into 5 – 6 rows; hindwing with brown pigmentation along outer margins at distal half; C) penes almost totally fused; and in the nymphal stage, A) maxillae with two distal dentisetae (proximal one bifurcated) and one proximal dentiseta (bifurcated, with one branch fringed; B) bristles on inner surface of hindtibia and hindtarsus with lateral margins serrated; C) lamellae of tergalius I with anal margin extended; tergalius VII with basal half convex and apical half narrowed.