Leptolingia imminuta, Liu, Yushuang, Shi, Chaofan & Ren, Dong, 2011

Liu, Yushuang, Shi, Chaofan & Ren, Dong, 2011, A new lacewing (Insecta: Neuroptera: Grammolingiidae) from the Middle Jurassic of Inner Mongolia, China, Zootaxa 2897, pp. 51-56 : 52-55

Leptolingia imminuta sp. nov.

( Figs. 1–2 )

Type material. Holotype, CHINA: Inner Mongolia, Chifeng City, Daohugou Village; Middle Jurassic; PMOL- AI00522A-B. Well-preserved part and counter part of wings.

Diagnosis. Costal area with two rows of cells basally, finishing at the middle of fore wing, and with only one row of cell distally; Rs1 originates at approximately one-fourth of the forewing’s length; MA forks at the same level as the separation of Rs2 from Rs. MP forks near base of wing, opposite separation of MA from Rs. CuA forks almost opposite separation of Rs1 from Rs; CuP bifurcates slightly before the separation of Rs1 from Rs, 1A terminates on posterior margin, opposite fork of CuP.

Description. Forewing. The left and right forewings almost overlap with each other completely, from the photo ( Fig. 2 A), they look like one forewing; but in fact, they are in different planes which preserved a part of left or right forewing respectively.

Length 25 mm, width 10 mm (preserved part), the estimated total length 30 mm. conspicuous wide banded markings and white annulets distributed irregularly are well preserved. Costal area with two rows of cells basally, finishing at the middle of fore wing, and with only one row of cell distally, costal and subcostal veinlets are numerous and simple. Sc runs parallel with R1 for a considerable distance, Rs arising close to base of wing, four branches preserved, Rs1 originates at approximately 1/4 of wing’s length. MA coalesced basally with Rs for a very short distance and then separating from it, MA forks at same level as origin of Rs2 from Rs, about at middle of wing’s length; MP forks near base of wing, opposite separation of MA from Rs, anterior branch of MP simple, maybe with short branches close to wing margin; posterior branch of MP first forks distal to fork of MA. CuA forked distal to fork of CuP, almost opposite separation of Rs1 from Rs; CuP relatively long, forked slightly before separation of Rs1 from Rs, and close to first fork of CuA. 1A long, terminates on posterior margin opposite fork of CuP, 2A relatively long, terminates on posterior margin obviously beyond separation of MA from Rs, clear intercalary vein between1A and 2A, not reaching margin of wing and producing three rows of cells between 1A and 2A on base of wing; 3A poorly developed. Crossveins at posterior margin interlinked by veinlets. Dense crossveins present over entire wing, the main longitudinal veins with many minute trichobothria close to the wing margin.

Hindwing. Well-preserved, length 29 mm, width 11 mm, also with wide banded markings and white annulets ( Fig. 3 ). One row of cells in costal area, veinlets unforked, except for a few forked distally. As in the forewing, Sc and R1 parallel and equidistant to wing margin close to apex, Rs with 6–7 pectinate branches. Other veins are difficult to observe clearly due to overlapped left and right hindwings. Distal parts of branches preserved with end twigging evident.

Etymology. From the Latin imminuta , meaning diminished, in reference to the small size of the wings (approximately half the size as other known grammolingiids)”.

Remarks. Leptolingia imminuta sp. nov. is much smaller than all other species of Leptolingia , which, for example, have the following wing lengths: L. jurassica Ren with 40 mm long forewings, L. tianyiensis Ren with 41 mm long forewings, L. calonervis Shi, Yang & Ren with 47 mm forewing and L. shartegica Khramov with 54 mm long forewing.

Leptolingia imminuta sp. nov. shares with L. tianyiensis two rows of cells in the basal costal area only of the forewing, and one row of cells in the distal part. Also, 1A terminates on the posterior margin at about the same level of the separation of Rs1 from Rs. It differs from L. tianyiensis by MP forked at approximately the same level as the separation of MA from Rs, MA forks at the same level as Rs2 from Rs, the venation pattern of MP, and the two longer rows of cells in the costal area, which terminate at about the same level as Rs2 from Rs. Leptolingia imminuta sp. nov. is easy to distinguish from L. jurassica , L. calonervis and L. shartegica by having two rows of cells only present in the basal part of costal area (two rows of cells present along the entire costal area in the latter three species), MA forks at the same level of separation as Rs2 from Rs (MA with forking close to the wing margin in the latter three species), and 1A terminating on the posterior margin at approximately the same level as the fork of CuP (1A terminated on the posterior margin distal to the forks of CuP in the latter species). In addition, it differs from L. jurassica by a relatively long 2A terminating on the posterior wing margin distinctly distal of the fork of MP. It differs from L. shartegica by MP being forked at approximately the same level as the separation of MA from Rs (MP forked distal of the separation of MA from Rs), and CuA is not dichotomously branched. It differs from L. calonervis by CuP without obvious pectinate branches, and 1A terminating on posterior margin opposite fork of CuP (CuP with 4 main pectinate branches, and 1A terminating on posterior margin distinctly distal to the fork of CuP in latter species).

Figures

FIGURE 1. Leptolingia imminuta sp. nov. Photograph of the holotype, PMOL-AI 00522 B. Scale bars represent 5 mm.

FIGURE 2. Leptolingia imminuta sp. nov. A, photograph of forewings of the holotype PMOL-AI 00522 B. B, the venation of forewings of the holotype PMOL-AI 00522 B. Scale bars represent 5 mm.

FIGURE 3. Leptolingia imminuta sp. nov. A, photograph of hind wings of the holotype PMOL-AI 00522 B. B, the venation of the hind wings of the holotype PMOL-AI 00522 B. Scale bar represents 5 mm.