Promalactis arciformis Wang, 2019

Wang, Shuxia & Jia, Yanyan, 2019, Taxonomic study of the genus Promalactis Meyrick, 1908 (Lepidoptera: Oecophoridae) IV. The sakaiella species group, with descriptions of fifteen new species, Zootaxa 4563 (3), pp. 491-515 : 503-504

Promalactis arciformis Wang , sp. nov.

( Figs 13 , 28 , 38 )

Type material. MALAYSIA: Holotype ♂, Mt. Trusmadi (5.44°N, 116.45°E), Sabah, 1223 m, 11.II.2018, coll. Mujie Qi, slide Nos. JYY17636. Paratypes (3♂, 3♀): 2♀, 8–11.II.2018, other same data as holotype, slide Nos. JYY17634 ♀, JYY17635 ♀; 1♂, Gunong Monkobo , Sabah, 945 m, 14¯ 23.VIII.1987, coll. K.R. Tuck, slide No. BMNH-33556 ( BMNH) ; 2♂, 1♀, Gunong Monkobo , Sabah, 975 m, 7¯ 13.VIII.1987, coll. K.R. Tuck, slide Nos. BMNH-33557 ♂, BMNH-33578 ♀ ( BMNH) .

Diagnosis. This new species is similar to P. bornensis sp. nov., P. cribrata sp. nov. and P. oliviformis sp. nov. in the forewing having an elongate elliptical spot at base of dorsum, a postmedian fascia, and an distal patch; in the male genitalia by having a U-shaped uncus and a separated gnathos. It can be distinguished from P. cribrata sp. nov. and P. oliviformis sp. nov. by having a costal process, which are absent in the latter two species; from P. bornensis sp. nov. by the flagelliform costal process slightly curved and extending outward almost horizontally, and the juxta lacking the lateral lobes; in P. bornensis sp. nov. the costal process is dilated ovately and extends straightly upward, and the juxta has slender lateral lobes.

Description. Adult ( Fig. 13 ) wingspan 9.5¯11.0 mm. Head with vertex snowy white, frons yellowish brown, occiput dark brown. Labial palpus with second segment ocherous yellow on inner surface, ocherous brown on outer surface; third segment with basal 1/4 white, distal 3/4 dark ocherous brown, approximately as long as second segment, pointed at apex. Antenna with scape white; flagellum with basal 1/4 white, distal 3/4 white and dark brown on dorsal surface, dark brown on ventral surface. Thorax and tegula dark brown. Forewing orange yellow; dorsum with a black sub-elliptical spot at base, edged with a white line along outer margin; postmedian fascia from distal 1/4 of costal margin widened to tornus, broad, deep silvery grey, edged with blackish brown scales, within postemedian fascia at tornus set a yellowish brown spot surrounded by black scales; distal patch deep grey mixed with brown, not distinctly diffused; cilia greyish brow along distal part of costal margin and around tornus, ocherous yellow along termen. Hindwing and cilia deep grey. Foreleg black, tarsus white at apex of each tarsomere on outer side; midleg pale grey on inner side, blackon outer side; hindleg pale grey on ventral side, greyish black on dorsal side, tarsus white at apex of each tarsomere on dorsal side.

Male genitalia ( Fig. 28 ): Uncus broad U-shaped, connected by a weakly sclerotized narrow band basally; lateral arms lanciform, narrowly rounded at apex. Gnathos with lateral arms elongate digitate, with microspinules in distal 1/3, longer than uncus lateral arm. Tegumen short and broad, concave at middle in small triangle anteriorly. Valva with basal half wide and subparallel, distal half gradually narrowed to a rounded apex, obliquely extending upward, deeply incised from basal 1/3 of costa obliquely outward to saculus, forming a groove with dentate outer margin. Costa with a flagelliform process arising from about middle, slightly narrowed to apex, curved at base, almost extending outward hoirizontally to apex of valva, bearing dense setae. Sacculus almost uniform, with dense setae from basal 1/4 to apex, distal 1/3 fused with valva. Saccus approximately 2/5 length of sacculus, wide at base, narrowed to basal 2/5, then subparallel to rounded apex. Juxta weakly sclerotized, subquadrate, slightly narrower distally; apex straight, reaching anterior 2/5 of tegumen; basal lobe digitate. Aedeagus slender, slightly curved, pointed at apex, approximately 1.2 times as long as valva; cornutus absent.

Female genitalia ( Fig. 38 ): Apophyses anteriores strong, about 3/10 length of apophyses posteriors. Eighth tergum concave at middle on posterior margin, with spinules on posterior area. Ostium bursae large, semicircular, folded laterally. Ductus bursae membranous, slender, thickened toward corpus bursae distally, two times length of corpus bursae. Corpus bursae elliptical; signum narrow, elongate, with denticles along margins and in surface.

Distribution: Malaysia.

Etymology. This epithet is derived from the Latin arcus and formis, referring to the arched costal process of the valva.

Figures

FIGURES 11–16. Adults of Promalactis spp. 11. P. spiniflagellata sp. nov., holotype, ♂; 12. P. grandilobata sp. nov., holotype, ♂; 13. P. arciformis sp. nov., holotype, ♂; 14. P. bornensis sp. nov., holotype, ♂; 15. P. oliviformis sp. nov., holotype, ♂; 16. Head of P. apicidigitata sp. nov. Scales: 9–15 =1.0 mm, 16 =0.5 mm.

FIGURES 27–31. Male genitalia of Promalactis spp. 27. P. grandilobata sp. nov., holotype, slide No. DZH12117; 28. P. arciformis sp. nov., holotype, slide No. JYY17636; 29. P. cribrata sp. nov., paratype, slide No. BMNH-33577; 30. P. bornensis sp. nov., holotype, slide No. MNHU-NK011; 31. P. oliviformis sp. nov., holotype, slide No. BMNH-33555. Scales =0.2 mm, 29a, b =0.1mm (not available for No. 30).

FIGURES 37‒40. Female genitalia of Promalactis spp. 37. P. bicornea sp. nov., paratype, slide No. JYY17547; 38. P. arciformis sp. nov., paratype, slide No. JYY17635; 39. P. cribrata sp. nov., paratype, slide No. JYY17665; 40. P. bornensis sp. nov., paratype, slide No. MNHU-NK009. Scales =0.2 mm (not available for No. 40).