CLADOENDESIS OF EPHEMEROPTERA

A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z 

Autapomorphies of Centroptella/g1.

(1) Secondary swimming setae on outer sides of the larval cerci in distal part of the cercus have oval transverse bases and form a regular row (Kluge et al. 2020: Figs 59, 121–131); in this respect they resemble the primary swimming setae on the inner side of the cercus (ibid.: Fig. 132), but they are smaller and less densely distributed.

Characters of Centroptella/g1 of unclear phylogenetic status: common with Potamocloeon in Protopatellata. 

(2) The larva has the structure of the tibia modified and different on each pair of legs, so that the patella-tibial suture is absent on forelegs and greatly shifted distally on the middle and hind legs; a row of long setae, which in some other taxa forms a transverse arc, in Centroptella is greatly stretched along the tibia, being different on the fore, middle and hind legs (Kluge et al. 2020: Figs 16–18, 49–51, 90–92); the female imago and subimago of Centroptella/g1 has the usual leg structure, with the patella-tibial suture not shifted distally, but without patella-tibial suture on forelegs. This leg structure is characteristic of the plesiomorphon Protopatellata and has striking similarity with the Afrotropical taxon Potamocloeon, which undoubtedly belongs to Protopatellata and has no features of Baetovectata (Kluge 2019). The Neotropical taxon Cloeodes/g1, which some authors have confused with Centroptella (see above), has none of these features, and its larval and imaginal leg structure is typical for Anteropatellata (Kluge 2017).

Other characters of Centroptella/g1 of unclear phylogenetic status.

(3) Another peculiar character of Centroptella is the presence of a pair of spaced transverse rows of long bifurcate setae on certain abdominal sterna of the larva (Kluge et al. 2020: Figs 58, 117–119); in different species these setal rows are present on sterna II–VI or on part of them, at least on sterna IV–V. Identical setal rows are found in a few other, non-related taxa (Potamocloeon, Cloeodes, selected species of Procloeon/g2).

...

Plesiomorphies of Centroptella/g1.

...

Systematic position of Centroptella/g1.

In spite of the character (2), Centroptella undoubtedly belongs to the holophyletic taxon Baetovectata, based on (1) presence of two marginal intercalaries in each space of wing (Kluge et al. 2020: Fig. 149), (2) narrow and arched gonovectes of penis (ibid.: Figs 77–80, 141–143, 146, 150–152) and (3) medially inclined subimaginal gonostyli when they are developing under larval cuticle (ibid.: Figs 79, 148).