(Panephemeroptera Euephemeroptera Euplectoptera Anteritorna Bidentiseta Furcatergaliae  
Fimbriatotergaliae Fossoriae Ephemera/fg9 Hexagenia/fg1 - Eatonica/g1)

Nomen hierarchicum: Eatonica/g1 [g:1913] (incl. Litobrancha, Eatonigenia)

In circumscription fits:

 Eatonica/g1: Kluge 2004: 241

References. Kluge 2004: * * *

Autapomorphy of Eatonica/fg1.

(1) In imago and subimago 1st segment of gonostylus ventrally with apical rounded projection, which projects distad of place of attachment of 2nd segment (McCafferty 1971a: Fig.7; 1971b: Fig.1C,2C; 1973: Fig.912).

Character of Eatonica/fg1 of unclear phylogenetic status.

(2) Larval flagellum of antenna without long setae, with short sparse setae only (unlike Hexagenia/fg2 and Ephemera/fg10).

Size. Fore wing length 1024 mm.

Distribution. Nearctic, Afrotropical an Oriental Regions.

The taxon Eatonica/fg1 is divided into:

1. Litobrancha

2. Eatonica/g2 

3. Eatonigenia