The damsel-dragonfly described herein was collected from the middle part of the Badaowan Formation of the Tuziakeneigou outcrop, Karamay City, Xinjiang, northwestern China (locality in Zheng et al., 2016: fig. 1). Abundant bivalves, gastropods, spinicaudatans, insects, sporopollen, and plants were reported from the Badaowan Formation (Deng et al., 2010), which was considered to be uppermost Rhaetian–Sinemurian stages (Sha et al., 2015). The insect fauna in this section is represented by Protorthophlebia latipennis and Dorsettia, both have recorded in the Lower Lias of England, and was regarded as earliest Sinemurian in age (Zheng et al., 2016).

The specimen was examined dry using a Nikon SMZ1000 stereomicroscope. Observation was augmented by temporary wetting with laboratory alcohol which improved the contrast between the fossil and the matrix, eliminating the surface irregularity of the latter. Photographs were taken using a Canon 5D digital camera and the line drawings were prepared from photographs using image-editing software (CorelDraw X7 and Adobe Photoshop CS6). The specimen is housed in the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences (NIGPAS).

The higher classification of fossil and extant Odonatoptera is based on the phylogenetic system of Bechly (1996). The nomenclature of the dragonfly wing venation used in this paper is based on the interpretations of Riek (1976) and Riek and Kukalová-Peck (1984), as modified by Nel et al. (1993) and Bechly (1996). Wing abbreviations are as follows: AA: anterior anal; AP: posterior anal; Arc: arculus; Ax: primary antenodal crossvein; C: costa; Cr: nodal crossvein; CuAa: distal branch of anterior cubitus; CuAb: proximal branch of anterior cubitus; CuP: posterior cubitus; DC: discoidal cell; IR: intercalary radial vein; MAa: anterior branch of anterior median; MAb: posterior branch of anterior median; MP: posterior median; N: nodus; “O”: oblique vein; Pt: pterostigma; RA: anterior radius; RP: posterior radius; Sn: subnodal crossvein; ScP: posterior subcosta.

Order ODONATA Fabricius, 1793

Subordinal clade ISOPHLEBIOPTERA Bechly, 1996

Subclade ISOPHLEBIIDA Bechly, 1996

Superfamily ISOPHLEBIOIDEA Handlirsch, 1906–1908

Family CAMPTEROPHLEBIIDAE Handlirsch, 1920

Genus Honghea gen. nov.

Type species. Honghea xui sp. nov.

Etymology. The generic name is after the Chinese palaeobotanist Dr Honghe Xu, in gratitude for his help with fieldtrip.

Diagnosis. Wing length ca. 45 mm; distal angle of discoidal cell not quite acute; Ax1 and Ax2 of convergent obliquity; no antefurcal crossveins; basal area between MAa and MP slightly narrower than that between MP and CuA; Pt broad, not braced; MAa short, ending on MP just below IR1 base; RP2 base slightly distal of Sn; CuAa with one row of long cells between it and MP; CuAa with one or two rows of cells between it and posterior wing margin; RP2, IR2, RP3/4 nearly straight; one row of long cells between MAa and MP, IR2 and RP3/4, and RP2 and IR2.

Honghea xui sp. nov. (Fig. 1, Fig. 2, Fig. 3, Fig. 4 and Fig. 5)

Etymology. The specific name is after Dr Honghe Xu.

Material. Holotype, NIGP165288a, b, part and counterpart of a well-preserved male damsel-dragonfly (Fig. 1A–B); deposited in the NIGPAS.

Type stratum and locality. Tuziakeneigou outcrop, Karamay City, Xinjiang, China; Badaowan Formation, Lower Jurassic (uppermost Rhaetian–Sinemurian).

Diagnosis. The same as for the monotypic genus.

Description. Specimen NIGP165288a, b (Fig. 1, Fig. 2, Fig. 3, Fig. 4 and Fig. 5), forewing. Wing length 45.5 mm, width at level of N, 8.77 mm; distance from wing base to Arc 5.24 mm, from Arc to N 14.62 mm, from N to Pt 17.61 mm, and from Pt to wing apex 8.01 mm. Median area free of crossveins. CuP strong, separating submedian and subdiscoidal areas at 0.91 mm basal of Arc. DC open (Fig. 3). Subdiscoidal area broad, free of crossveins. MAb rather short, 0.42 mm long, and well aligned with distal free part of CuA. CuA separated from MP 5.48 mm from wing base, directly toward posterior wing margin. Area between CuAa and MP with one row of cells basally, expanded distally; CuAa with one or two rows of cell between it and posterior wing margin. MP slightly curved, reaching posterior wing margin 31.59 mm from wing base, at 69% of total wing length. MAa distally zigzagged, more or less parallel with MP, ending on MP just below IR1 base; postdiscoidal area with one row of large cells basally, narrower distally. Primary antenodal crossveins strong, Ax1 1.37 mm basal of Arc, and Ax2 3.1 mm distal of Ax1; Ax2 and Ax1 of distinct and converging obliquity. No secondary antenodal crossveins present between C and ScP; six secondary antenodal crossveins present between ScP and RA distal of Ax2. Twelve postnodal crossveins present between C and RA, not aligned with 12 postsubnodal crossveins between RA and RP1 basal of Pt. Nine antesubnodal crossveins present. No antefurcal crossvein present in area between RP and MA basal of midfork (base of RP3/4). Five postnodal crossveins present distal of Pt. Bqr space between RP, RP2, IR2 and oblique vein “O” very long and narrow, with one row of cells and 12 crossveins. Single oblique vein “O” present, 7 cells and 7.93 mm distal of base of RP2. RP2 slightly curved. Midfork 4.87 mm distal of Arc, closer to Arc than to N. Nodal structures well preserved (Fig. 4); Sn oblique and well aligned with Cr. Base of IR2 close to midfork, 2.84 mm distally. RP2 originating 0.77 mm distal of Sn. IR1 originating five cells and 5.77 mm distal of base of RP2; IR1 basally zigzagged, more or less parallel to RP1. Pt not braced (Fig. 5), long and narrow, sclerotized, 4.56 mm long and 1.36 mm wide. Area between MAa and RP3/4 widened distally, with many cells along posterior wing margin. Area between RP3/4 and IR2 with one row of cells before level of Pt, and one or two rows of cells along posterior wing margin. Area between IR2 and RP2 with one row of narrow cells before level of distal side of Pt. Area between RP2 and IR1 with one row of cells before Pt base, slightly widened distally with two rows of cells. Area between IR1 and RP1 distally widened, with probably five rows of cells along posterior wing margin.

Honghea xui belongs to Campterophlebiidae by the presence of the following characters (Li et al., 2012 and Nel et al., 2009): medium size; no secondary antenodal crossveins present between C and ScP; forewing discoidal cell basally opened, correlated to absence of shifting of distal side (MAb) of discoidal cell distinctly distal of arculus.

Within Campterophlebiidae, H. xui has the basal pars of areas between MAa and MP and between MP and CuA of similar widths, only one row of cells between MA and MP, one row of cells between MP and CuAa for a long distance, these forewing characters being only shared with Karatawia Martynov, 1925, Melanohypsa Pritykina, 1968, Zygokaratawia Nel et al., 2008, and Ctenogampsophlebia Petrulevičius et al., 2011. Affinities between Karatawia and Honghea can be excluded because the former has the areas between RP2 and IR2, and RP3/4 and IR2 expanded along the wing margin, Sn aligned with RP2 base, and MAa ending on the wing margin (Nel et al., 1993). Melanohypsa has only the wing base preserved, however, it differs from Honghea in having the arculus nearer to Ax1 than to Ax2 instead of nearer to Ax2 than to Ax1 in the latter, an acute distal angle of the discoidal cell, and several antefurcal crossveins instead of none (Nel et al., 1993 and Pritykina, 1968).

Honghea quite resembles Zygokaratawia in having a narrow cubito-anal area, a long basal part of CuA before its branches, the basal areas between MP and CuA being as broad as the postdiscoidal area (distally constricted), a straight MP, a zigzagged MAa being much weakened distally, a short CuAa, and a non-basally recessed pterostigma (Nel et al., 2008). However, the former has a larger size (45 mm compared to 35 mm in the latter), no distinct constriction in the area between RP3/4 and IR2 (present in the latter), RP2 slightly distal of Sn (well aligned in the latter), one row of cells in the area between IR2 and RP3/4 (many cells along the posterior wing margin in the latter).

Honghea nearly shares all the forewing characters of Ctenogampsophlebia but differs from the latter as follows: larger size (45 mm compared to ca. 35 mm long in the latter); base of RP3/4 nearer to arculus than to nodus (lying midway between the arculus and the nodus in the latter); RP2 slightly distal of Sn (aligned with Sn in the latter); larger pterostigma size (4.6 mm compared to 3.7 mm long in the latter); CuA with two rows of cells between it and posterior wing margin (three cells in the latter); and one row of long cells present between IR2 and RP3/4, and IR2 and RP2 (four cells in the latter).

In conclusion, Honghea shares the most characters of Zygokaratawia and Ctenogampsophlebia, but differs from these genera in having a larger size, RP2 slightly distal of Sn, and a narrow area between IR2 and RP3/4. It has RP2 slightly distal of Sn, distinguishing from other campterophlebiid genera.

The second earliest Jurassic damsel-dragonfly, Honghea xui gen. et sp. nov., is described from the Lower Jurassic Badaowan Formation of the Junggar Basin, NW China. Within Campterophlebiidae, Honghea gen. nov. resembles the Middle Jurassic genera Zygokaratawia and Ctenogampsophlebia, but differs from other campterophlebiid genera in having RP2 slightly distal of Sn. The new discovery adds to the diversity of campterophlebiid damsel-dragonflies in China.