Litholinga rhora Ren, 2002

Jouault, Corentin, Legendre, Frédéric, Perrichot, Vincent, Condamine, Fabien L. & Nel, André, 2022, Redescription of Litholingia rhora Ren, 2002 (Neuroptera: Grammolingiidae) from the Middle Jurassic of Daohugou, Palaeoentomology 5 (1), pp. 20-26 : 22-23

Litholinga rhora Ren, 2002

Revised diagnosis. Forewing with RP with branches distally forked (no branch deeply forked), with at least eight posterior branches; PCu terminated on the posterior margin beyond the second dichotomy of RP; CuA forks after the fork of CuP; CuA and CuP forked beyond the second dichotomy of RP; coloration pattern with alternating broad light and smaller dark stripes.

Material. Specimen NIGP 177501, housed in the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Science, China.

Locality and horizon. Middle-Upper Jurassic deposit of Daohugou, Haifanggou Formation, China.

Description. Mesothorax massive, ca. 3.60 mm wide (distance between forewing insertions), and 3.09 mm long; other body parts not clearly visible. Leg with numerous small setae.

Forewing 54.2 mm long and 18.1 mm wide. Forewing elongate, narrow and pubescent, the main longitudinal veins and wing margin scattered with minute trichobothria. Costal area relatively narrow, slightly wider than subcostal space, with only a series of gradate veins producing two rows of cells, a few simple crossveins near wing base. Subcostal veinlets unforked. ScP running parallel with RA. Dense crossveins present between ScP and RA. RP arising close to the base of the wings, with at least eight branches (some indistinct distally). First branch of RP arising at 0.13 of wing length, no branch of RP deeply forked, second dichotomy of RP located at midlength from first and third dichotomy, anterior to CuA fork and nearly aligned with CuP fork, nearly all branches of RP forked distally. Stem of M short with M fork slightly distal to first RP dichotomy, MA forked far distal from MP fork, MA branches forked near wing margin, with six apical branches. MP forking just after third dichotomy of RP and far from CuA from, with numerous branches forked near wing margin. CuA field larger than MP field forking after second dichotomy of RP and after CuP fork, with numerous branches forked near wing margin. CuP field smaller than CuA field, with five apical branches, CuP finishing near distal part of basal wing third. PCu long and pectinate, terminating slightly distal second dichotomy of RP. Wing base with two or three rows of cells distinctly present between A1 and A2. A2 short, abruptly bent toward wing margin. Dense cross venation between veins over entire wing. Trichosors clearly present along wing margin with several of them between each vein along the margin of the wing. Coloration pattern visible with alternating light and dark stripes, light ones (5–6) broader than dark ones, several additional white spots visible on sides of black bands between veins.

Hind wing with a vein configuration similar to forewing, except for costal field with only one row of cells.

Identification key to Litholingia species

1. CuP heavily branched (with five branches reaching wing margin), wings coloration pattern with thin dark stripes and broad white stripes............... Litholingia rhora

- CuP pectinate or branched, if branched with less than five branches reaching wing margin, wings coloration pattern with broad dark stripes and thin white stripes.............................2

2. CuP pectinate............................................ Litholingia longa

- CuP with a variable number of branches but never pectinate.....................................................................................3

3. Fourth branch of RP deeply forked, three branches of CuA originating at its fork..................... Litholingia polychotoma

- Fourth branch of RP forked far distad its origin, two branches of CuA originating at its fork..............................4

4. Third branch of RP deeply forked, CuP likely with less than four branches, RP with seven branches..................................................... Litholingia ptesa

- Third branch of RP forked far distad its origin, CuP with four branches, RP with at least nine branches............................................ Litholingia eumorpha