(Panephemeroptera Euephemeroptera Euplectoptera Anteritorna Bidentiseta Branchitergaliae
Heptagennota Pentamerotarsata Radulapalpata 

Nomen hierarchicum: Heptagenia/f7=g6 [f:1901; g:1863] (sine Kageronia; incl. Dacnogenia, Stenonema).

In circumscription fits:

 Heptagenia/f7=g6: Kluge 2002: 169.

References. Kluge 1993: *; 2004: * * * *.

Characters of Heptagenia/f7=g6 of unclear phylogenetic status. 

(1) 2nd+3rd segment of labial palp [specialized as scraping see Radulapalpata (1)] is blunt, thus the field of scraping setae terminates close to the end of sclerotized ridge (Kluge 2004: Fig.55:I). The same in Cinygma; probably, independently appeared apomorphy. In Kageronia, Ecdyonurus/fg1 and Rhithrogena/fg1 form of this segment is different.

(2) Whole outer margin of each larval femur always bears long hairs, and usually bears long stout blunt irregularly situated setae (Kluge 2004: Fig.55:C) (only in selected species these setae are short and pointed). Such femoral setation never occurs in other Radulapalpata [see Plesiomorphies of Heptagenia/f6=g5].

(3) Larval claws lack denticles on inner margin [see Pentamerotarsata (4)] (subapical denticles on anterior side of claw can be present or absent). The same in all other Radulapalpata except for Kageronia.

Plesiomorphy of Heptagenia/f7=g6. Larval caudalii retain swimming setae [vestigial see Pentamerotarsata (6)].

Size. Fore wing length 616 mm.

Distribution. Holarctic, Oriental Region and Central America (dominate in Holarctic).

The taxon Heptagenia/f7=g6 is divided into:

1. Heptagenia/f8=g7

2. Dacnogenia

3. Stenonema/fg1
3.1. Stenacron

3.2. Stenonema/fg2

3.3. Macdunnoa