Nymphs of (A, C, E) Protobaetisca bechlyi Staniczek, 2007 (holotype, Lower Cretaceous, Upper Aptian, Crato Formation, holotype, SMNS 66620) and (B, D, F) Baetisca rogersi Berner, 1940, (USA, coll. SMNS). A–B head and prothorax, ventral view: ant – antenna; cly – clypeus; cx – coxa; cxc – coxal cavity; fr – frons; frp – frontal projections; ge – gena; lbr – labrum; md – mandible; mx – maxilla; prm – prementum; pm – postmentum; pst – prosternum. C–D general ventral view: I–IX – abdominal segments I–IX; cr – head; cl – pretarsal claw; cx – coxa; fe – femur; frp – frontal projections; ns – notal shield; pst – prosternum; ta – tarsus; ti – tibia; tr – trochanter, arrow marks traces of transversal crest. E–F caudal end of abdomen, ventral view: IX–X – abdominal segments IX–X; ce – cerci; gb – genital bud; pp – paraproct; tf – paracercus.

 
 
  Part of: Staniczek AH, Storari AP, Godunko RJ (2022) Revised systematics, phylogeny, and paleontology of the mayfly family Baetiscidae (Insecta: Ephemeroptera). Arthropod Systematics & Phylogeny 80: 389-409. https://doi.org/10.3897/asp.80.e82845