(Panephemeroptera Euephemeroptera Euplectoptera Anteritorna Bidentiseta Furcatergaliae  
Ephemerella/fg1 Pantricorythi Tricoryptera Leptohyphes/fg1 - Allenhyphes)

Nomen hierarchicum: Allenhyphes/g(1) [g:1999]

In circumscription fits:

gen. Allenhyphes: Hofmann & al. 1999: 67

Allenhyphes/g(1): Kluge 2004: 336

References. Henry 1986: (Leptohyphes vescus): ; Hofmann & al. 1999: ; Wiersema & McCafferty 2000: (I); Molineri & Flowers 2001: ; Kluge 2004: * * *

Autapomorphy of Allenhyphes.

(1) Unlike all other mayflies, male imaginal paracercus is specialized and involved to genital apparatus: apex of its 2nd segment bears a stout spine-like seta directed ventrally, perpendicular to paracercus (Molineri & Flowers 2001: Fig.2; Kluge 2004: Fig.105:F). Unique character.

Characters of Allenhyphes of unclear phylogenetic status.

(2) Mouth apparatus is somewhat specialized (Hofmann & al., 1999: Fig.147152): maxilla is filtering, with enlarged tuft of apical setae [see Ephemerella/fg1 (16)] (but it retains blunt canines, well-developed two dentisetae and vestigial 3-segmented maxillary palp); labial submentum with enlarged lamellate margins overlapping maxillae. Non-unique apomorphies.

(3) Tergalii [see Leptohyphes/fg1 (1)] have no processes on ventral bifurcate lobe, thus each tergalius II-V is 3-lamellate; tergalius VI is 1-lamellate, without ventral lobe. The same in Tricorythodes.

Plesiomorphies of Allenhyphes. Unlike Tricorythodes: Scuto-lateropostnotal muscle of metathorax is not so large, posterior scutal protuberances are not convergent posteriorly, lateropostnotum is not fused with epimeron (the same in Leptohyphes/fg2). Lateroparapsidal suture somewhat retains curvation initial for Ephemerella/fg1 [see Leptohyphes/fg1 (4)], merging with transverse interscutal suture laterad of medioparapsidal suture. Hind wings [of peculiar structure see Leptohyphes/fg1 (2) ] are present in male, but lost in female; however, metathoracic wing muscles S.ESm and MTm are retained not only in male, but in female as well. 1st tarsal segment is short and fused with tibia.

Unlike Leptohyphes/fg2: Tergalius II (gill operculum) has well-developed costal flap of ventral lobe [see Leptohyphes/fg1 (1)]. Lateropostnotum retains straight lateropostnotal crest forming one line with infrascutellar-lateropostnotal arm.

Unlike Haplohyphes, gonostylus is 3-segmented, i.e. with developed distal segment [short see Pantricorythi (2)].

Size. Fore wing length 3 mm (see Tricoryptera). 

Distribution. Neotropical Region.

Nominal species in Allenhyphes/g(1):

flinti Allen 1973 [Leptohyphes] ,//,,

michaeli Allen 1978 [Leptohyphes] syn.subj. vescus [Leptohyphes]

vescus Allen 1978 [Leptohyphes]

yusuaia Belmont & Cruz & Hamada 2015 [Tricorythopsis] ??

See also: 

Leptohyphes/fg1 INCERTAE SEDIS

Furcatergaliae INCERTAE SEDIS