Topiris sericella Sterling & Lees, 2025

Sterling, Mark J., Price, Ben W. & Lees, David C., 2025, A revision of the hitherto neglected genus Topiris Walker, 1863 (Lepidoptera, Xyloryctidae) with taxonomic notes on the genus Athrypsiastis Meyrick, 1910, ZooKeys 1229, pp. 297-368 : 297-368

Topiris sericella Sterling & Lees sp. nov.

Figs 10 , 37 A, B

DNA barcode.

N / A.

Type material.

Philippines: Holotype • ♂, Taytay , Palawan. plains. 22.iv.1913, A. E. Wileman leg., fwl 8.5 mm, specimen no. NHMUK 010219786 , slide no. NHMUK 010316873 . Paratype • ♂, same collection data as holotype, specimen no. NHMUK 010219788 , slide no. NHMUK 010316878 .

Diagnosis.

The hindwings of this species are slightly grey towards the termen and have an indistinct greyish terminal line. In the male genitalia, the vinculum is almost straight above the saccus, the valvae are postmedially narrow and uniformly sclerotised, the costal ventral membrane of the valva is smooth, almost without setae and with a substantial, strongly curved, sclerotised process arising from its base. The aedeagus is long and has a long filament-like distal projection with a small distal thickening.

Description.

Male (Fig. 10 ). Wingspan 18–19 mm, forewing length 8–8.5 mm. Head: frons with shining white appressed scales; vertex with white appressed scales, two tufts of long white scales laterally on vertex pointing inwards and posteriorly, remains of tuft of long white scales on posterior part of occiput, overlaying a thick collar of broad white and pale ochreous scales from anterior margin of prothorax; pilifers cylindrical with small tuft of short bristles; maxillary palps whitish. Labial palps long (almost 3 × diameter of eye), strongly recurved, white, projecting away from head; basal segment pale ochreous; second segment long, strongly curved; third segment long and thin with white and some pale ochreous appressed scales. Haustellum with basal third scaled silver white. Antenna 2 / 3 length of forewing, bipectinate, scape ochreous white, flagellum dorsally ochreous white for a few segments, otherwise dark brown, pectinations black, densely covered with short white sensillae, reducing at ¾, apical portion filiform. Thorax: (worn) ochreous white mixed with white, tegulae shining silver white; foreleg with femur white, long thin tibial epiphysis, tibia and tarsus greyish brown, mid leg ochreous whitish, hind leg white with thin tuft of long white scales. Forewing moderately broad, costa slightly arched towards base, thereafter straight, apex broadly rounded, termen angled inwards, tornus very obtusely angled, shining silver white, unmarked except for a small line of brown scales from base of costa to 1 / 5, a patch of thicker silver scaling along length of dorsum on one specimen, cilia long, silver white. Hindwing rounded with apex slightly projecting; silvery white but with some darker tipped scales, particularly towards the termen giving a slightly greyish appearance and with indistinct greyish terminal line. Ventrally, surface of forewing dark brown towards costa, otherwise pale greyish ochreous, veins pale greyish ochreous; hindwings white.

Female. Unknown.

Pre-genital abdomen. White, long white anal tuft. Tergal spines on posterior part of T 2 – T 7, T 8 almost unsclerotised, sternites weakly sclerotised. Apodemes almost straight; venulae slightly curved.

Male genitalia (Fig. 37 A, B ). Uncus broad, anterior margin of dorsal surface very weakly emarginate, slightly narrowing medially, apically almost rectangular, slightly spatulate. Gnathos fused medially, lateral arms thin and lightly sclerotised, medial plate small and lightly sclerotised, weakly projecting posteriorly from lateral arms. Tegumen band broad and strongly arched, lateral extensions of tegumen longer than width of tegumen band. Vinculum large and robust, U shaped, arms parallel distad of saccus, base significantly projecting anteriorly beyond base of valvae. Saccus large. Juxta with small sclerotised basal plate, anellus lobes broad. Valva long, broad at base, strongly sclerotised postmedially and strongly tapering apically, apex of valva thin and rounded with tuft of short bristles, costal ventral membrane confined to basal half of valva, surface smooth and with few setae, long curved sclerotised process arising from base of ventral membrane from costa, broad at base, no setae apart from brush of shortish hairs at apex, saccular margin of valva slightly convex, strong ventral sclerite postmedially. Sacculus large, well sclerotised, longer than broad. Saccular process commencing near costa of valva, strongly sclerotised, broad and straight at base, short and hooked, terminating in a sharp point, no setae or bristles. Aedeagus long, slightly recurved with undulating distal filament-like projection of sheath and small, pointed, distal thickening. Bulbus ejaculatorius long with two coils and a large, elongated hood.

Remarks.

The male genitalia of this species displays some of the characteristic features of the salva group (e. g., aedeagus with long filament-like distal projection and with a distal thickening and vinculum not diverging strongly distad of saccus) and some of the characteristics of the candidella sub-clade (e. g., costal ventral membrane with long sclerotised process arising from base and valva tapering apically). The combined analysis (Fig. 2 , which contains morphological data only from T. sericella ) shows that T. sericella + the T. candidella sub-clade form a supported sub-clade (pp = 0.98) and we place T. sericella in the candidella group.

Biology and early stages.

Early stages unknown. Adults found in April.

Distribution.

Known from Palawan, Philippines.

Etymology.

sericella — from sericus (lat.), silky. A reference to the silky white gloss on the forewings. The epithet is an adjective in the nominative singular.

Figures

Figure 2. Combined morphological and molecular tree run in MrBayes 3.2. 7 under a split-partition gamma and inverse gamma model (with posterior supports where > 0.94) and with the morphological part of the matrix mapped onto this tree using WinClada v. 1.00. 08. This tree shows supporting characters (filled circles show forward nonhomoplasious changes, which may be either synapomorphies or autapomorphies; unfilled circles show forward changes with homoplasy or reversal) for Topiris and other ingroup species. The support values in red are posterior probabilities of at least 0.94 for a two partition run in MrBayes 3.2. 7 for the combined 723 character matrix. HT = holotype, NT = neotype, PT = paratype, m = male, f = female. Character numbers appear above the circles. State numbers appear below the circles.

Figures 4–21. Dorsal images of Topiris spp. 4 Topiris candidella Walker, 1863, holotype ♂ 5 T. candidella, Sarawak, leg. A. R. Wallace, ♂ 6 T. candidella, Brunei, ♂ 7 T. cinderella sp. nov., paratype ♂ 8 T. ochrotincta sp. nov., holotype ♂ 9 T. schneeweissella sp. nov., holotype ♂ 10 T. sericella sp. nov., holotype ♂ 11 T. salva (Meyrick, 1932), comb. nov., neotype ♂ 12 T. salva (Meyrick, 1932), comb. nov., paraneotype ♂ 13 T. salva, ♂ 14 T. albogrisella sp. nov., holotype ♂ 15 T. lacteella sp. nov., paratype ♂ 16 T. madonna sp. nov., holotype ♂ 17 T. meyricki sp. nov., holotype ♂ 18 T. sampitella (Lvovsky, 2014), comb. nov., holotype ♂ 19 T. thunbergella sp. nov., holotype ♂ 20 T. albidella sp. nov., holotype ♂ 21 T. digiticosta sp. nov., holotype ♂. Scale bar: 10 mm.

Figures 32–39. Male genitalia of Topiris spp. 32 A, B T. candidella Walker, 1863, Brunei, slide no. NHMUK 010316445 33 A, B T. candidella, Sarawak, slide no. NHMUK 014331342 34 T. cinderella sp. nov. A holotype, slide no. NHMUK 010316400 B paratype, slide no. NHMUK 010316448 35 A, B T. ochrotincta sp. nov., holotype, slide no. NHMUK 010316401 36 A, B T. schneeweissella sp. nov., holotype, slide no. NHMUK 010316358 37 A, B T. sericella sp. nov., holotype, slide no. NHMUK 010316873 38 A, B T. salva (Meyrick, 1932), comb. nov., slide no. NHMUK 010316399 39 A, B T. salva (Meyrick, 1932), comb. nov., paraneotype, slide no. NHMUK 010316441. Scale bar: 1 mm.