CLADOENDESIS OF EPHEMEROPTERA
Heptagennota Pentamerotarsata Radulapalpata
Nomen hierarchicum: Cinygma/fg(1) [f:1988; g:1885]
In circumscription fits:
— gen. Cinygma: McDunnough 1933: 74
— tribus Cinygmini Kluge 1988: 303
— tribus Cinygmatini: Wang & McCafferty 2004: 44
— Cinygma/fg(1): Kluge 2004: 188
References. McDunnough 1933: *; – Needham & Traver & Hsu 1935: *; – Tshernova 1949 (Heptagenia abnormis): '; – Edmunds & Jensen & Berner 1976: *; – Tshernova 1976: *; – Lehmkuhl 1979a: ' '; – Kluge 1988: * *; – 1993: * *; – 2004: * * *
Autapomorphies of Cinygma.
(1) Labrum is strongly narrowed, narrowing from its base toward apex, its width at any place is less than length (Tshernova 1949: Fig.4:2). Unique apomorphy among Heptagennota [see Heptagennota (1)].
(2) Maxilla [see also (5)] has a single canine developed (unlike other Radulapalpata, which have all three canines subequal); on apical margin of maxilla pectinate setae [see Radulapalpata (3)] are completely lost, distal margin of maxilla is entirely covered with dense long setae (Kluge 2004: Fig.61:D,H). Non-unique apomorphy (see Index of characters [1.1.32]).
Characters of Cinygma of unclear phylogenetic status.
(4) Each superlingua is widening toward its apex (Kluge 2004: Fig.61:G), lateral margins of superlinguae are divergent (unlike majority of Rhithrogena/fg1), but apices are not curved laterally (unlike Heptagenia/f5=g4). Shape of superlinguae is somewhat similar to that of Bleptus.
(5) On maxilla [see (2)] ventral row of setae [see Branchitergaliae (1)] is straight, at apex not curved laterally (Kluge 2004: Fig.61:D). The same in Paegniodes and Epeorus/fg1; possibly, symplesiomorphy.
(6) 2nd+3rd segment of labial palp [specialized as scraping – see Radulapalpata (1)] is blunt, thus its field of scraping setae terminates close to the end of sclerotized ridge (Kluge 2004: Fig.61:J). The same in Heptagenia/f7=g6; possibly, independently appeared apomorphy. In Kageronia, Ecdyonurus/fg1 and Rhithrogena/fg1 form of this segment is different.
(7) Outer-dorsal margin of larval femur [flattened – see Heptagennota (1)] bears a regular row of long stout setae. Non-unique apomorphy: similar setal row occurs in some other rheophilous mayflies. Among Radulapalpata the same setal row is present in Rhithrogena/fg1; possibly synapomorphy; similar, but less dorsal row is present in Ecdyonurus/fg1.
(8) Tergalii lost ability of rhythmical respiratory movements. Non-unique apomorphy (see Index of characters [1.3.30]); among Radulapalpata the same in Rhithrogena/fg1; possibly synapomorphy [for comment – see Rhithrogena/fg1 (6) below].
(9) Larval caudalii lack whorls of stout setae on hind margins of segments. Among Radulapalpata the same in Rhithrogena/fg1 (possibly synapomorphy) and Raptoheptagenia, while in Heptagenia/f5=g4 whorls of stout setae are present.
Plesiomorphies of Cinygma (unlike Rhithrogena/fg1). Maxillary palp is not so strongly specialized as in Rhithrogena/fg1 (Kluge 2004: Fig.61:D). Labial palp without bifurcate setae. Imaginal and subimaginal lateroparapsidal sutures are not curved laterally, terminate near medioparapsidal sutures (Kluge 2004: Fig.61:A–B). Larval and adult patella-tibial suture is developed on middle and hind legs only (unlike larval Rhithrogena/fg3).
Variable characters of Cinygma. On hind wing bifurcation of MA is present in integrum [C.] and lyriformis [E.] (like in all other Radulapalpata), but is lost in dimicki [C.] (non-unique apomorphy – see Index of characters [2.2.67]).
Size. Fore wing length 11–13 mm.
Distribution. Amphipacific Sector of Holarctic: All 3 species occur in Western Nearctic, and only one of them – lyriformis [E.] — is distributed in Eastern Palaearctic including Urals.
Nominal species in Cinygma/fg(1):
abnormis Tshernova 1949 [Heptagenia] — syn.subj. lyriformis [Ecdyonurus]
dimicki McDunnough 1934 [Cinygma]
hyalinus Esben-Petersen 1916 [Ecdyonurus] nom.praeocc. — syn.obj. peterseni [Ecdyonurus] — syn.subj. lyriformis [Ecdyonurus]
integrum Eaton 1885 [Cinygma]
lyriformis McDunnough 1924 [Ecdyonurus] --/
peterseni Lestage 1930 [Ecdyonurus] — syn.subj. lyriformis [Ecdyonurus]
Radulapalpata INCERTAE SEDIS