Thyridosmylus fuscomarginatus Xu, Wang & Winterton

Xu, Han, Winterton, Shaun L., Wang, Yongjie & Liu, Zhiqi, 2017, Two new species of Thyridosmylus Krueger, 1913 from Madagascar (Neuroptera, Osmylidae), ZooKeys 724, pp. 43-52 : 45-46

Thyridosmylus fuscomarginatus Xu, Wang & Winterton sp. n. Figs 1, 2

Diagnosis.

Pronotum light yellow with three longitudinal dark brown stripes; posterior margin of forewing with brown markings, branches of vein A1 marked with a dark brown spot, area around outer gradate cross-veins fenestrate with pale venation; sternite 8 in female reduced, extending anteriorly to form a forward process in lateral view; spermatheca complex with 11-12 sacs, basal sac large.

Description.

Head. Vertex yellowish-brown with black setae; compound eyes black, ocelli yellow, each one anteriorly edged with a black spot. Antennal flagellum light yellow with dark yellow apex; scape and pedicel light yellow; frons brown. Thorax. Pronotum light yellow with a dark brown longitudinal stripe in middle and parallel two dark brown markings on both sides, three markings linked by a latitudinal light brown stripe; meso- and metanotum brown. Legs. Yellow with brown setae; claws brown. Wings (Fig. 1). Forewing length 17-18 mm, width 5-6 mm; membrane hyaline; cross-veins in the basal half of costal field dark brown, paler distally; pterostigma light brown; Rs with 13-14 branches; distal part of branches of vein Rs, M and Cu edged with brown markings, branches of A1 edged with an irregular and clear dark brown spot; area around outer gradate cross-veins hyaline with pale venation, appearing fenestrate; cross-veins among branches of Rs, M, Cu and A edged with fuscous markings. Hindwing length 15-16 mm, width 4-5 mm; membrane hyaline; veins yellowish; pterostigma light brown; Rs with 11 branches, cross-veins among Rs branches forming two series of gradates; basal MP with a spur. Male genitalia (Fig. 2 a–g). Tergite 8 and sternite 8 quadrangular with brown setae; tergite 9 narrow and extended distally in dorsal view; sternite 9 subtriangular in lateral view; ectoproct with a dorsal rod-like process (Fig. 2b), base inflated and distal part with numerous brown setae; callus cercus approximately rounded; gonarcus approximately triangular in lateral view (Fig. 2d) and narrow arch-like in dorsal view (Fig. 2e), basally articulated internally with tergite 9, gonarcus dorsally sclerotized and ventrally membranous (Fig. 2d); entoprocessus narrow and reflexed dorsally with a backward process at the corner of bend, distal margin membranous (Fig. 2d); gonarcus anterior apodeme goblet-shaped; mediuncus lobes C-shaped in lateral view (Fig. 2f), thickened basally and sclerotized well but distal part translucent and expanding dorsal-medially and ventrally (Fig. 2g); parameres sclerotized, horn-shaped, and thickened medially (Fig. 2c). Female genitalia (Fig. 2 h–i). Tergite 8 quadrate, sternite 8 reduced, close to tergite 9 and extending anteriorly to form a forward process in lateral view; tergite 9 narrow and constricted at the level of ectoproct; gonopophyses 9 and gonocoxite 9 closely associated, gonocoxite 9 thick finger-like with gonostylus 9 distally; ectoproct coniform, callus cercus rounded; spermathecae complex, each comprised of 11-12 sacs, basal sac large and long (Fig. 2h).

Material examined.

Holotype. Female. MADAGASCAR: Mahajanga Prov., Parc National de Baie de Raly, 12.4 km, 337° NNW Soalala, elev. 10 m, 16°00'36"S, 45°15'54"E, 26-30.xi.2002, coll. Fisher, Griswold et al., collected at night, tropical dry forest (CASC). Paratypes. 1 male. MADAGASCAR: Mahajanga Prov., Forêt de Tsimembo, 8.7 km, 336° NHW Soatana, elev. 20 m, 19°1'17"S, 44°26'26"E, 21-25.xi.2001, coll. Fisher, Griswold et al., collected at night, tropical dry forest (CASC). 1 female. MADAGASCAR: Mahajanga Prov., Parc National de Baie de Raly, 12.4 km, 337° NNW Soalala, elev. 10 m, 16°00'36"S, 45°15'54"E, 26-30.xi.2002, coll. Fisher, Griswold et al. Collected at night, tropical dry forest (CASC). 1 female. MADAGASCAR: Antsiranana Prov., Ankarana National Park, Aurelien Hotel, 140 m, 12°58 ’07.5” S 49°08 ’12.8” E, 16.xii.2016, coll. Hu Li. (CAU). 1 male. MADAGASCAR: Antsiranana Prov., 3 km, W Sakalava Beach, 12°17'10"S 49°22'00"E, 40 m, 21-23.i.2001, coll. M. E. Irwin, E. I. Schilinger, R. Harin’ Hala. (CASC).

Etymology.

The specific name " fuscomarginatus ", a compound from Latin fusco- ( fuscus ) and marginatus- (margin), in reference to the colour and pattern of markings on the outer and posterior margin of forewings.

Distribution.

Madagascar (Antsiranana, Mahajanga)

Remarks.

The forewings markings of Thyridosmylus fuscomarginatus sp. n. are characteristic, clearly differed from other Thyridosmylus species by the dark posteromarginal stripe.