Orthobittacus maculosus, Liu, Sulin, Shih, Chungkun, Bashkuev, Alexei & Ren, Dong, 2016

Liu, Sulin, Shih, Chungkun, Bashkuev, Alexei & Ren, Dong, 2016, New Jurassic Hangingflies (Insecta: Mecoptera: Bittacidae) from Inner Mongolia, China, Zootaxa 4067 (1), pp. 65-78 : 71-72

Orthobittacus maculosus sp. nov.

( Figs. 4 , 5 )

Etymology. The species name is derived from the Latin word macula (spot), and refers to the presence of spots on the wings.

Material. Holotype, CNU-MEC-NN2014084 p/c, part and counterpart, dorsal view.

Horizon and locality. Jiulongshan Formation, latest Middle Jurassic, Daohugou Village, Shantou Township, Ningcheng County, Inner Mongolia, China.

Diagnosis. Two crossveins between C and Sc; two pterostigmal crossveins between R1 and R2; M with six branches.

Remarks. Orthobittacus maculosus sp. nov. ( Figs. 4 , 5 ) is assigned to the genus Orthobittacus Willmann, 1989 based on the following generic diagnostic characters in the forewing: Sc reaching the anterior margin distal to the forking of R4+5; two crossveins between C and Sc; R1 forking and running through pterostigma; two pterostigmal crossveins; R4+5 and R4 bending distinctively; Rs with four branches.

Comparisons. Orthobittacus maculosus sp. nov. differs from O. polymitus Novokshonov, 1996 and O. abshiricus Willmann, 1989 in having M with six branches in the forewing (the other two species with seven branches), two crossveins between C and Sc (one crossvein for the other two species) and two pterostigmal crossveins (none present in the other two species).

Description. An almost complete body with one pair of separated wings (forewing, hind wing) and a pair of overlapped wings. Female, large-sized. Light-colored or white spots present in fore- and hind wings.

Head medium-sized and two partial antennae preserved ( Figs. 4 A, B, 5A).

Pronotum, mesonotum and metanotum well-preserved; postnotum also visible in dorsal view ( Fig. 5 A).

Basal part of forewing narrow with wide posterior anal field. Vein Sc reaching the wing margin distal of the bifurcation of R4+5; R1 forking and bending slightly anteriorly, reaching antero-apical wing margin; Sc with one crossvein to R1; Rs with four branches, two pterostigmal crossveins (Pcv’s) between R1 and R2, two crossveins between R2 and R3, proximal part of R4 curving anteriorly, two crossveins between R3 and R4 and two between R4 and R5; Rs forking proximal to the bifurcation of M; M with six branches; five crossveins between R5 and M1, two between R4+5 and M1, three between M1 and M2 and one between M1 and M2+3. M2 and M3 bending posterior with two crossveins between them, two crossveins between M3 and M4; M4 and M5 bending as in M2 and M3, two crossveins between M4 and M5, two between M5 and M6, and one between M4+5 and M6; one crossvein between M1+2+3 and M4+5 distal of the forking of M; Cu1 and Cu2 curving posteriorly with four crossveins between them; 1A and 2A long, 1A reaching the middle of the posterior margin, two crossveins between 1A and 2A. ( Fig. 5 B).

Hind wing same shape as forewing. Sc reaching the costal margin distal to the forking of R4+5 with one crossvein between them; R1 forking before reaching the antero-apical wing margin and one pterostigmal crossvein (Pcv) between R1 and R2; Sc with one subcostal crossvein (Scv) to R1; Rs with four branches, the bifurcation of M distal to the forking of Rs; M with six branches, M4+5 bifurcation proximal to the M2+3 forking; Cu1 and Cu2 parallel with five crossveins between them; 1A and 2A long, 1A reaching the posterior margin far distal to the origination points of Rs and M; many cells between Rs and M ( Fig. 5 C).

Abdomen. Abdomen with ten visible segments. Female genital structure well-preserved; subanal plate and cerci present, covered with small, short setae in dorsal view ( Figs. 4 , 5 A).

Abdomen 14.2 mm long, body 34.8 mm long, forewing 22.7 mm long, 6.1 mm wide; hind wing 18.8 mm long, 5.3 mm wide.

Figures

FIGURE 4. Orthobittacus maculosus sp. nov., holotype, CNU-MEC-NN 2014084 p / c, part and counterpart, dorsal view. A. Photograph of part. B. Photograph of counterpart. C. Photograph of genitalia in dorsal view, under alcohol. D. Line drawing of genitalia in dorsal view. Abbreviations: C: cercus. SaP: subanal plate, T 10: tergum X. Scale bars represent 1 mm.

FIGURE 5. Orthobittacus maculosus sp. nov., holotype. A. Line drawing of part. B. Line drawing of left forewing. C. Line drawing of left hind wing. Scale bars represent 2 mm in A, 1 mm in B – C.