(Panephemeroptera Euephemeroptera Euplectoptera Anteritorna Bidentiseta Branchitergaliae  
Eusetisura - Coloburiscus/fg1)

Nomen hierarchicum: Coloburiscus/fg1 [f:1963; g:1888] (incl. Coloburiscioides, Murphyella)

In circumscription fits:

— tribus Coloburiscini: Riek 1970

— subfam. Coloburiscinae: Edmunds & Allen & Peters 1963: 11

— fam. Coloburiscidae: Landa 1973: 156

— Coloburiscus/fg1: Kluge 2000: 251

References. Edmunds & Allen & Peters 1963: *; – Koss & Edmunds 1974: *; – Edmunds 1975: *; – Kluge 2004: * * * *. 

Autapomorphies of Coloburiscus/fg1.

(1) Dorsal side of mandible with a field of long setae, proximally bordered by a regular arched row of the same setae (Kluge 2004: Fig.38:A). Unique apomorphy: in other mayflies, if regular rows of setae are present on mandible, they have other form.

(2) Larva has something like notal shield, as its pronotum and mesonotum are immobile fused together all over their width, and fore protoptera are fused together (Kluge 2004: Fig.37:A); fore protoptera [see Eusetisura (5)] convergent by their apices, in larva of last instar contiguous apically; their hind margins (except for extreme apices) are fused together by means of a triangular plate, which fills an area between them and posterior margin of mesonotum. This fusion of fore protoptera differs from that of Discoglossata, where protoptera apices are divergent.

(3) Larval femur of middle leg [see (4)] bears the same 2 rows of long filtering setae as on fore leg [see Eusetisura (1)] (at the same time tibia of middle leg, as well as in other Eusetisura, has no specialization peculiar for fore legs) (Kluge 2004: Fig.38:C). Unique apomorphy.

(4) Larval femora of all legs [see (3)] bear stout spine-like setae, which form transverse rows: at least a row on outer side of femur, and a more distal row on dorsal side near inner margin are present (Kluge 2004: Fig.38:B-D).

(5) On larval abdomen denticles on posterior margin of each tergum and sternum are fused forming an integral transverse sclerotized striated plate (Kluge 2004: Fig.37:B). This plate is integral beginning from tergum I or II to IX, and from sternum III or V to VIII; on sternum IX this plate is paired, being located by sides of protogonostyli. Selected segments of caudalii have apical tube-like striated formations of the same origin; these segments are separated one from another by 4, 8, 16 or larger number of usual segments.

(6) On each tergalius I–VII [see Eusetisura (7)] costal and anal ribs [marginal – see Branchitergaliae (3)] are unusually strongly thickened, sclerotized, covered with large stout spine-like setae; membranous part of tergalius is vestigial or lost, thus tergalius has a form of bipointed fork (Riek 1973: Fig.3) (only in Murphyella tergalii are completely lost).

(7) In male imago and subimago 1st segment of fore tarsus is strongly shortened, so that its length is subequal to width. Non-unique apomorphy (see Index of characters [2.2.76]). 

Characters of Coloburiscus/fg1 of unclear phylogenetic status. 

(8) Maxilla (Kluge 2004: Fig.37:C) has indeterminate number of canines and dentisetae: canines have 3–4 apices (instead of three initial ones, unlike two in Isonychia/fg1 and one in Oligoneuria/f3=g4); number of dentisetae is 2 or 3, varying individually [unlike initial two ones – see Bidentiseta (1)].

(9) Imaginal and subimaginal paracercus is vestigial, multisegmented or 1-segmented. Non-unique apomorphy (see Index of characters [2.3.22]).

Plesiomorphies of Coloburiscus/fg1. Maxilla with nearly rectangular apical angle (unlike acute angle in Isonychia/fg1 and Discoglossata); 1st segment of maxillary palp is not shortened, only 2 times shorter than 2nd+3rd segment (like in Isonychia/fg1, unlike Discoglossata); maxillary and labial palps [see Eusetisura (2)] retain oblique suture separating 2nd and 3rd segment in such a way, that 2nd segment is shorter on inner side and longer on outer side (unlike Isonychia/fg1 and Discoglossata). In cubital field of fore wing several (4–6) simple or branched veins go from CuA to basitornal margin [see Anteritorna (1)]. Unlike Discoglossata, larval and adult middle and hind legs retain patella-tibial suture. All claws of imago and subimago are ephemeropteroid. Gonostylus has 2 distal segments.

Size. Fore wing length 12–20 mm.

Distribution.  Distribution. Notogea: Australia, New Zealand and Chile-Patagonian Region of South America.

The taxon Coloburiscus/fg1 is divided into:

1. Coloburiscoides

2. Coloburiscus/fg2

2.1. plesiomorphon Coloburiscus/fg3

2.2. Murphyella