Jordanhemiphlebia electronica, Kaddumi, 2009

Lak, Malvina, Fleck, Günther, Azar, Dany, Engel Fls, Michael S., Kaddumi, Hani F., Neraudeau, Didier, Tafforeau, Paul & Nel, André, 2009, Phase contrast X-ray synchrotron microtomography and the oldest damselflies in amber (Odonata: Zygoptera: Hemiphlebiidae), Zoological Journal of the Linnean Society 156 (4), pp. 913-923 : 921-922

JORDANHEMIPHLEBIA ELECTRONICA KADDUMI

GEN. ET SP. NOV. ( FIGS 18 , 19 , 20C )

Etymology: The specific epithet is based on the Greek term elektron (meaning, ‘amber’).

Material: Holotype specimen deposited in Eternal River Museum of Natural History , Amman, Jordan.

Type locality: Wadi Zerqa ; Jordan; Lower Cretaceous; Barremian .

Diagnosis: As for the genus (vide supra).

Description: Wing hyaline, petiole not preserved but after rather broad anal area with AA parallel to AP, petiole probably quite short, with AA separating from AP near wing base, and not below CuP; one long cell between AA and AP, below discoidal cell and Ax1 and basal of point of fusion between AA and CuA; Ax1 and Ax2 not preserved, no secondary antenodal cross-vein; distance between apex of discoidal cell and nodus 2.4 mm, discoidal cell basally closed; MAb 0.5 mm long; MP not strongly curved near its base; terminal kink of CP at nodus reduced; nodal Cr of normal obliquity; subnodus nearly vertical; CuA strongly zigzagged, reaching posterior wing margin opposite subnodus; one row of cells in cubito-anal area; MP straight, reaching posterior wing margin one cell distal base of RP2; one row of cells between MA and MP; MA distally zigzagged; base of RP3/4 between arculus and nodus, very close to nodus; base of IR2 opposite subnodus; one large cell between base of RP3/4 and IR2; base of RP2 two cells distal of subnodus; five postnodal cross-veins not aligned with four postsubnodal cross-veins; no oblique cross-vein between IR2 and RP2; IR1 very short, between pterostigma and wing apex; RP1 with a strong angle below pterostigmal brace; pterostigmal brace strong and oblique; pterostigma covering one cell, 0.6 mm long, 0.3 mm wide; only four cells between C and RA distal of pterostigma.

Discussion: This wing is nearly identical to the hindwings of the Cretaceous hemiphlebiid genus Parahemiphlebia , the only difference being the weaker obliquity of the pterostigmal brace, which is not aligned with the proximal portion of RP1 ( Bechly, 1998b; Jarzembowski et al., 1998). The second hemiphlebiid genus Cretarchistigma differs from Jordanhemiphlebia in the longer vein IR1 that begins two cells basal to the pterostigma, instead of below the pterostigma as in Jordanhemiphlebia and Parahemiphlebia . Jordanhemiphlebia differs from the third Cretaceous hemiphlebiid genus, Electrohemiphlebia , in the nodal Cr and subnodus of normal obliquity, instead of being vertical. Lastly, Jordanhemiphlebia differs from Hemiphlebia in the shorter IR1, shorter area between C and RA distal of pterostigma, broader cell between the bases of RP3/4 and IR2 below the subnodus, and probably AA separating from AP very close to the wing base, instead of close to the level of CuP ( Münz, 1919).

Figures

Figure 18. Jordanhemiphlebia electronica Kaddumi gen. et sp. nov., holotype, apical half of wing. Scale bar = 1 mm.

Figure 19. Jordanhemiphlebia electronica Kaddumi gen. et sp. nov., holotype, basal half of wing. Scale bar = 1 mm.

Figure 20. Wing reconstructions. A–B. Electrohemiphlebia barucheli gen. et sp. nov., holotype ARC 372.1. A, forewing. B, hindwing. C, Jordanhemiphlebia electronica Kaddumi gen. et sp. nov., holotype. Scale bars = 2 mm. N, nodus; Ax1, Ax2, primary antenodal crossveins; RA, radius anterior; RP, radius posterior; IR, intercalary radial veins; MA, median anterior; MP, median posterior; CuA, cubitus anterior; Pt, pterostigma.