Phylloleon stangei Lu, Ohl & Liu, 2019

Phylloleon stangei Lu, Ohl & Liu sp. nov.

( Figs 6 View Figure 6 , 7 View Figure 7 )

Diagnosis. Generally same as for the genus. Additionally, hind wing strongly narrowed, slightly longer and much more acutely produced than forewing.

Material. Holotype, NIGP 168259 , amber piece preserving a partly preserved adult female of Phylloleon stangei , together with a hymenopteran, a midge, a beetle, two pseudoscorpions, and a mite. It is polished in the form of a flattened round cabochon, with diameter about 30.0 mm, height about 5.0 mm .

Etymology. Dedicated to Dr Lionel A. Stange, one of the famous taxonomists of Myrmeleontidae .

Description. Body length 7.99 mm; head 0.53 mm long and 0.80 mm wide; distance between compound eyes 0.35 mm; antenna length 2.59 mm; prothorax 0.54 mm long and 0.27 mm wide; mesothorax 0.98 mm long and 0.89 mm wide; metathorax 0.51 mm long and 0.66 mm wide; forewing 12.68 mm long and 4.14 mm wide; hind wing 14.62 mm long and 2.12 mm wide; abdomen 5.73 mm long and 1.72 mm wide.

Head orthognathous, wider than long. Compound eyes large, semi-globular; diameter of eyes much shorter than distance between compound eyes. Antenna nearly as long as length of head plus thorax, clubbed distad.

Prothorax much longer but narrower than head; meso- and metathorax robust, metathorax slightly smaller than mesothorax. Wings elongated, transparent and immaculate.

Forewing leaf-like, with narrow wing base and acuminated apex. Costal space quite narrow proximally, strongly widened medially, and again slightly narrowed distad, with c. 43 simple veinlets. ScA absent; ScP and RA fused together, slightly bending and running to wing margin posteriad wing apex; subcostal crossveins absent. Presectorial crossveins absent. Hypostigmal cell long. RP þ MA originating near wing base, and diverging into RP and MA distad midpoint of wing; 11 crossveins present in RA space; RP pectinately branched into six branches, with few crossveins among these branches; infra radial cell short. M proximally leaving a short oblique stem of MA that is fused with R near wing base; MA distinctly curved posteriad at distal 1/3 and distally with three branches. MP1 long, almost straight for a long distance, distally distinctly curved, with two simple and one distally forked branches. CuA and CuP diverging near wing base; MP 2 þ CuA pectinately branched from proximal 1/3, with seven branches, posterior three branches of MP 2 þ CuA1 distally bifurcated, while remaining MP 2 þ CuA1 branches simple, CuA2 deeply forked; CuP pectinately branched into nine simple branches. A1 short and zig-zagged, bifurcated from its midpoint into two simple branches, connected with CuP by two short crossveins; A 2 þ A3 short, bifurcated.

Hind wing strongly narrowed, nearly half of forewing width, with acuminate apex. Costal space narrow, about three times as wide as subcostal space, with 28 veinlets, most of which are simple. ScP and RA fused together and straightly running to wing margin slightly posteriad wing apex; subcostal crossveins absent. RP þ MA originating from midpoint of wing; five crossveins present in RA space; RP and MA diverging slightly distad basal radial cell; RP pectinately branched into seven branches, with posterior two branches distally forked. MA distally bifurcated. Six presectoral crossveinlets present. MP1 and MP2 long, MP1 distally bifurcated, MP2 simple, space between them slightly broadened distad, with six crossveins. CuA pectinately branched into nine short simple branches; CuP and anal veins absent.

Legs slender and long; femur and tibia almost equal in length; tibiae and tarsi bearing several long spinous setae, these setae on tibiae longer than those on tarsi, about 1/6 × length of tibia; tibial spurs slightly longer than tarsomere 1; numerous short setae present along tibiae and tarsi; tarsus much shorter than tibia, tarsomere 1 and tarsomere 5 nearly equal in length, but much longer than the other tarsomeres; paired simple pretarsal claws present, slender and distally curved, opposable on last tarsomere; arolium absent.

Abdomen slenderly elongate, about 0.7 times as long as body length. Female genitalia preserved; segment 8 much shorter than segment 7, with a broad ventral sclerite (putative gonocoxite 8); tergum 9 about 2/3 × length of tergum 8, slightly tapering ventrad in lateral view; gonocoxites 9 ovoid, bearing long setae along ventral margin; ectoprocts nearly semicircular, much broader than gonocoxite 9, with long setae; callus cerci not detected.

Remarks. The new species differs from the congeneric species Phylloleon elegans by the forewing with less protruded apex and the strongly narrowed and acutely protruded hind wing. In the latter species, the forewing is slightly longer than hind wing, with apex much more protruded, and the hind wing is broad, nearly as wide as forewing. In addition, P. stangei has much fewer forewing MP 2 þ CuA1 branches than P. elegans .

Considering the strongly narrowed hind wing and the presence of six presectorial crossveins, the new species appears also similar to Caririneura microcephala from the Lower Cretaceous of Brazil. However, the new species can be distinguished from C. microcephala by the leaf-like forewing, with strongly broadened costal space and produced wing apex, and by the presence of more crossveins between RA and RP þ MA as well as between RP þ MA and MP 1 in the forewing.