(Panephemeroptera Euephemeroptera Euplectoptera Anteritorna Bidentiseta Furcatergaliae  
Tricorythus/fg1Ephemerella/fg2 - Timpanoga/fg1)

Nomen hierarchicum: Timpanoga/fg1 [f:1984; g:1927] (incl. Attenella)

In circumscription fits:

— subtribus Timpanogae Allen 1984: 246

— complex genn. Timpanoga: McCafferty & Wang 1994a: 571

— subfam. Timpanoginae: McCafferty & Wang 2000: 41

— Timpanoga/fg1: Kluge 2004: 301

References. McCafferty & Wang 1994a: *; – 2000: * – Kluge 2004: * * *

Autapomorphy of Timpanoga/fg1.

(1) Tergalii III are lost, thus bilamellate tergalii, whose structure is typical for Ephemerella/fg1 [see Ephemerella/fg1 (7)], are present on abdominal segments IV–VII only (Kluge 2004: Fig.91:I). Unique apomorphy (see Table).

Plesiomorphies and variable characters of Timpanoga/fg1. Unlike Ephemerella/fg3, tergalii I [stick-like – see Ephemerella/fg1 (13)] are usually retained, being attached to posterior part of the segment (Kluge 2004: Fig.91:G–H) (while in other mayflies with stick-like tergalii I – Vietnamella, Melanemerella/fg1, Caenotergaliae and Potamanthus/fg1 – they are attached anteriorly); in Timpanoga/fg4 tergalii I are transferred to extreme posterior margin of the segment; in Attenella/g1 delantala [Ephemerella]) tergalii I are lost. Paired tergal projections [see Ephemerella/fg1 (19)] are nearly always retained at least on some segments, rarely lost (in Dannella). Unlike Teloganopsis and Hyrtanella/f2=Crinitella/g1, hind wing without prominent costal projection and with Sc terminating near apex.

Size. Fore wing length 6–14 mm.

Distribution. Mainly Nearctic, also in Europe.

The taxon Timpanoga/fg1 is divided into:

1. Attenella

2. Timpanoga/fg2

2.1. Eurylophella/fg1

2.1.1. plesiomorphon Dentatella

2.1.2. Eurylophella/fg2

2.2. Timpanoga/fg3

2.2.1. plesiomorphon Dannella

2.2.2 Timpanoga/fg4