Nototriadophlebia pritykinae, Béthoux & Anderson, 2023

Béthoux, Olivier & Anderson, John M., 2023, New light shed on Triadophlebiomorpha wing morphology and systematics (Insecta: Odonata), Geodiversitas 45 (17), pp. 479-496 : 491-494

Nototriadophlebia pritykinae n. gen., n. sp.

( Figs 7-9 )

urn:lsid:zoobank.org:act:BB1717F8-0D90-41B5-9D88-68689FB9B410

HOLOTYPE. — Specimen BP /2/20950ab, adpression preserving four wings ( Anderson collection, Evolutionary Studies Institute , University of the Witwatersrand, Johannesburg, South Africa; Figs 7 , 8 ).

PARATYPE. — Specimen BP /2/20986ab, adpression preserving a single wing ( Anderson collection, Evolutionary Studies Institute , University of the Witwatersrand, Johannesburg, South Africa; Fig. 9 ) .

E ScP

RA RP1 1 -rp 2

CuA

ScP F

RA RP1 1-rp2

DIAGNOSIS. — Area between the anterior wing margin and RA (distal to the nodus) widening gradually to ª/5 of wing length, where it is as wide as the RA-RP1 area (most prominent in forewing); first I- in the RP3+4-MA area (i.e. RP3+4 pseudo-fork; large orange arrows on Fig. 8A, F ) arising before RP3+4 mid-length; CuP+AA stem splitting into CuA and CuP+AA (as opposed to Cu and AA; large red arrow on Figs 8F , 9A, C, D ); AA reaching the posterior wing margin basal to the end of ScP; between the endings of MA and AA, posterior wing margin comparatively straight.

ETYMOLOGY. — The species epithet honours Lyudmila N. Pritykina, for her contribution to our knowledge of fossil Odonata , and of Triadophlebiomorpha in particular.

TYPE LOCALITY AND STRATIGRAPHY. — Both holotype and paratype were collected at Birds River (locality code ‘Bir 111’; see Anderson & Anderson 1984), South Africa; Molteno Formation; lower Carnian , Upper Triassic ( Anderson et al. 1998).

GENERAL DESCRIPTION

Fore- and hindwings subequal, very elongated, broadest at mid-length; wing length about 74 mm (as derived from holotype specimen; possibly down to 70 mm), maximum width about 11.0 mm (possibly down to 10.2 mm), width opposite nodus 7.1-7.6 mm); petiole long (about 12.8 mm) and narrow (width about 2.4 mm); ScP reaching the anterior wing margin basal to the first third of wing length; distal to the nodus, area between anterior wing margin and RA broadening gradually, at its broadest opposite the end of Irp 1+2 -rp 3+4; structure of the nodus and origin of RP+MA, RP and MA unknown; RP1/ RP2 fork in a position more distal than that of the point of origin of the first I- in the RP3+4 area; Irp 1 -rp 2 weakly differentiated, zigzagging along RP1; occurrence of 3 I- (and I+ between them) forming RP2 posterior pseudo-branches in the distal part of the area between RP2 and Irp 1+2 -rp 3+4; RP3+4 with a marked angle opposite the origin of the first I- (between RP3+4 and MA; large orange arrows on Fig. 8A, F ); the two first I- in the area between RP3+4 and MA branched; in this area, total of about 8 I- reaching the posterior wing margin; MA simple, rectilinear, very close to RP3+ 4 in its basal third; marked inflexion of the posterior wing margin opposite the ending of MA; MP originating from MP +Cu+AA with a slight obliquity; branches of MP and CuA not clearly distinguishable (probable occurrence of a CuAprlg), CuA with 2 branches at least, and with a I- distally branched between its two (first posterior) branches; MP and CuA covering more than a quarter (less than a third) of the posterior wing margin length; Cu+AA splitting into CuA and CuP+AA, CuA diverging very obliquely; CuP rectilinear, with about 4-5 posterior branches and I+ between them; AA gently curved, reaching the posterior wing margin basal to the end of ScP.

SPECIMEN DESCRIPTIONS

Specimen BP/2/20950 ( Figs 7 ; 8 )

Adpression preserving four wings, with side BP/2/20950a preserving the right forewing (isolated) and left wings in ventral aspect, and right hindwing in dorsal aspect (the three latter largely overlapping); and its reverse side BP/2/20950b.

Right forewing ( Figs 7 ; 8A, B ). Well preserved, with area basal to the nodus and small portion of apex missing; preserved length 55.6 mm, maximum width 10.7 mm, width opposite nodus about 7.6 mm.

Left forewing ( Figs 7 ; 8 C-E). Only anterior-most area decipherable; preserved length 73.2 mm; estimated total length about 74.2 mm.

Right hindwing ( Figs 7 ; 8C, D, F ). Well preserved, with nodal area and part of apex missing, and venation in the petiole difficult to decipher; basal to the nodus, RP and MA not distinguishable from each other (assumed to closely overlap); cubito-anal area preserved, showing a CuP+AA stem.

Left hindwing ( Figs 7 ; 8C, D ). Barely decipherable but for the posterior wing margin, with a sharp inflexion opposite the end of MA.

Figures

FIG. 7. — Nototriadophlebia pritykinae n. gen., n. sp., holotype, specimen BP/2/20950a (preserving the right forewing, isolated, in ventral aspect, and other wings,overlapping,in dorsal aspect),photograph (dry).Scale bar:10 mm.

FIG. 8. — Nototriadophlebia pritykinae n. gen., n. sp., holotype, specimen BP/2/20950a: A, B, right forewing (RFW); A, drawing of venation, with tentative reconstruction of wing base; B, photograph, location as shown on Fig. 7 (dry-ethanol composite, light-mirrored, flipped horizontally); C, D, overlapping left forewing (LFW), right hind wing (RHW) and left hind wing (LHW; in blue); C, drawing of venation; D, photograph, location as shown on Fig. 7 (dry-ethanol composite, fragments readjusted digitally); E, left forewing (LFW), drawing of venation isolated from C, with tentative reconstruction of the posterior area; F, right hind wing (RHW), drawing of venation isolated from C (large red arrow, CuP+AA stem). Scale bar: 10 mm.

FIG. 9. — Nototriadophlebia pritykinae n. gen., n. sp., paratype specimen, BP/2/20986b, left wing (large red arrows indicating the CuP+AA stem): A, B, overview; A, drawing of venation; B, photograph (light-mirrored); C, D, detail of cubito-anal area, location as indicated on B (large red arrows, CuP+AA stem); C, drawing of venation; D, photograph (light-mirrored). Scale bars: A, B, 10 mm; C, D, 2 mm.