(Panephemeroptera Euephemeroptera Euplectoptera Anteritorna Bidentiseta Furcatergaliae  
Leptophlebia/fg1 Atalophleboadentata Atalophlebopectinata Atalophleboculata  
- Terpides/g1)

Nomen hierarchicum: Terpides/fg1 [f:2009; g:1966]

In circumscription fits:

 Terpides-lineage: Savage 1986

 Terpides/fg1: Kluge 2008

 Terpides/fg1 = Terpidinae = gen. Terpides: Kluge 2009

References. Savage 1986: ; Kluge 2009: ; Kluge 2015: ;

Autapomorphies of Terpides/fg1.

(1) Larvae are secondarily actively swimming, siphlonuroid-like: head is hypognathous (Kluge 2015: Fig.7,10,11, 92), with frons and clypeus convex and sharply separated one from another by sides (Kluge 2015: Fig.57); paracercus has clusters of long dense setae on lateral sides of each segment border, each cercus has such clusters on median side only, that superficially resembles siphlonuroud setation (Kluge:  Fig.7, 92). In contrast to the primary swimming setae, the secondary swimming setae of Terpides/fg1 do not form longitudinal rows; their bases form either short transverse rows, or an irregular roundish field on each segment of cercus or paracercus (Kluge 2015: Fig.62-63). Being attached irregularly on lateral surfaces of paracercus and median surfaces of cerci, all swimming setae are inclined toward common flatness of caudalii (Kluge 2015: Fig.64); as a result of this, they lie at most in one flatness, that makes wrong allusion of regular longitudinal rows (Kluge 2015: Fig.60). The secondary swimming setae of Terpidinae are long and dense, but thin, with bases very small.

(2) Glossae are curved over ventro-laterally and have characteristic narrow shape (Demoulin 1966:(37): Fig.10n; Peters & Harrison 1974: Fig.16; Savage & Peters 1978: Fig.22; Savage 1984: Fig.41).

(3) Stout pointed spine-like setae on inner margin of 3rd segment of labial palp are conic and form a single regular longitudinal row, that gives this segment serrate appearance (Kluge 2015: Fig.5, 51)

(4) In contrast to the leptophlebiid archetype [see Leptophlebia/fg1 (8)] setae on inner side of fore tibia are not more dense than on inner sides of middle and hind tibiae; setae on outer side of tibia are either present both on middle and hind legs (Kluge 2015: Fig.12-14, 53-55), or absent on all legs (Kluge 2015: Fig.125-127).

(5) In larva uromere VII always lacks posterolateral spines, while previous and next uromeres can have posterolateral spines: posterlolateral spines on uromeres VIII and IX are always present; on uromere VI and more anterior either present, or absent. Independently, if larva has or has not posterolateral spines on abdominal segments VI and previous ones, in stage of subimago posterolateral spines are present only on segments VIII and IX. In imago posterolateral spines of segment IX are retained; spines of segment VII are either also retained, or vestigial, or lost.

 In most other mayflies larval posterolateral spines increase toward uromere IX.

(6) All imaginal and subimaginal claws are pointed. Non-unique apomorphy (see Index of characters [2.2.85]).

(7) Both distal segments of gonostylus are diminished both in subimago and in imago (Kluge 2009: Fig.23, 26; Kluge 2015: Fig.26-27, 76-77, 97-98); in Fittkaulus these segments are fused, forming a single segment (Kluge 2009: Fig.15).

(8) Penis bears a pair of thick sclerotized longitudinal bands with smooth straight margins; these bands are located on ventral side of penis and run along paired penial lobes (Kluge 2015: Fig.27, 28-29, 77, 78, 98, 99-101). 

In ontogenesis, penis is developed as the following. Larval protopenis represents a projection with unpaired proximal part and paired distal part, without gonopores (Kluge 2015: Fig.25, 75, 95) (unlike some other taxa, whose larval protopenis is entirely paired and/or have a pair of gonopores leading to gonoducts lined by cuticle). Subimaginal penis is much longer than the larval protopenis. When subimaginal penis is developed inside larval cuticle, its distal paired part is spread inside cuticle of larval protopenis, while its proximal unpaired part is crumpled proximad of larval protopenis. Subimaginal cuticle of distal part of penis, which is developed in spread condition inside the cuticle of protopenis, is somewhat sclerotized and colored by yellowish, while subimaginal cuticle of proximal part of penis, developing in crumpled condition, is membranous and colorless (Kluge 2015: Fig.30, 79). On subimaginal exuviae shad at molt from subimago to imago, distal sclerotized portions of paired penis lobes retain their shape, while proximal membranous portion is crumpled. Imaginal penis has approximately the same size as subimaginal one, but differs in shape, sclerotization and pigmentation. Its distal paired part, developing inside sclerotized part of subimaginal cuticle, can have shape different from the subimaginal one; its proximal part, developing inside membranous shapeless subimaginal cuticle, gets new shape, sclerotization and cuticular pigmentation. Imaginal penis has a pair of longitudinal sclerotized bands on ventral side; subimaginal cuticle has no these bands (Kluge 2015: Fig.30, 79).

Characters of Terpides/fg1 of unclear phylogenetic status. 

(9) On subimaginal cuticle of mesonotum, paired pigmented area, which is bordered by the mesonotal suture, is very narrow, in a form of a stripe along the medioparapsidal suture; posterior scutal protuberances are colorless and lacking microtrichiae. These features are well visible in species with intensive subimaginal cuticular pigmentation (Kluge 2009: Fig.14); in species with colorless subimaginal cuticle, shape of pigmented areas is poorly visible, but is the same.

(10) On subimaginal middle and hind legs of male and all legs of female 1st tarsomere (shortened and fused with tibia) is covered by microtrichiae, and 2nd5th tarsomeres are covered by blunt microlepides. Texture of 1st tarsomere of male is either the same [see below, Tikuna () and Fittkaulus ()], or different [see below, Terpides/fg2 ()].

(11) Hind wing is small, with prominent costal projection, Sc terminates just distad of costal projection and far from apex (Kluge 2009:  Fig.1213, 21, 24) (the same in many non-related taxa see Index of characters [2.2.62]).

Plesiomorphies of Terpides/fg1: difference from Atalophlebomaxillata and Atalophlebolinguata.

(12) Mandibles are more robust and have less convex outer margin than in Atalophlebomaxillata. 

(13) Unlike all Atalophlebomaxillata, apical flange of maxilla is absent (Kluge 2015: Fig.1-3).

(14) Unlike all Atalophlebomaxillata, distal dentiseta is retained [being non-pectinate, while the proximal dentiseta is pectinate see Atalophlebopectinata (1) (Kluge 2009: Fig.1)]. 

(15) Hypopharynx lacks lateral projections (unlike all Atalophlebolinguata).

Other plesiomorphies of Terpides/fg1. 

(16) In larva, imago and subimago patella-tibial suture is developed on middle and hind legs, being absent on fore legs only (Kluge 2015: Fig.12-14, 17-22, 53-55, 125-127) (see Index of characters [1.2.18], ibid. [2.2.82]).

(17) On fore wing fork of MA is asymmetrical [see Leptophlebia/fg1 (5)] (Kluge 2009: Fig.12-13, 21, 24, 28; Kluge 2015: Fig.32, 65, 85) (see Index of characters [2.2.43]); originally MA fork of Terpides was wrongly described as symmetrical (Demoulin 1966)

(18) Tergalii of all 7 pairs have both lamellae present, divided up to base; each lamella is slender, with stretched pointed apex; it is either lanceolate, or has short projections by sides of the terminal filament [see Leptophlebia/fg1 (10)] (Kluge 2009: Fig.69, 1618; Kluge 2015: Fig.34-38, 68-72, 87-91) (see Index of characters [1.3.23]).

Size. Fore wing length 59 mm.

Distribution. Neotropical Region.

The taxon Terpides/fg1 is divided into:

1. Terpides/fg2

2. Fittkaulus

3. Tikuna

See also:

Leptophlebia/fg1 INCERTAE SEDIS