Platyja vityaz, Zilli & Vos, 2021

Zilli, Alberto & Vos, Rob de, 2021, The sumatrana species group of the genus Platyja with descriptions of four new species (Lepidoptera: Erebidae), Fragmenta entomologica 53 (2), pp. 391-410 : 404

Platyja vityaz sp. n.

Description

Male (Fig. 11)

Habitus. Forewing length 33-34.5 mm. Outward form and pattern as in P. subtracta sp. n. and P. togutila sp. n. (described here above), with third joint of labial palpus as long as in the latter or slightly longer, and androconial pencils on pro- and mesotibiae yellow.

Male genitalia (Figs 35-36, 63-64). Tegumen long and narrow, vinculum approximately as long as tegumen, V-shaped, with robust arms; valva stout and wide, not constricted at base of cucullus, saccular lobe broad-based and little pronounced, subtriangular in outline with well round- ed tip, cucullus dilated, with short and thick, thumb-like apical process and prominent costal angle, edge of cucullus almost blunt, that on left cucullus slightly smoother that that of right one, that shows small hump before costal angle; juxta asymmetrical, large, consisting of paired triangular plates separated midventrally by membrane, the right plate prolonged apically into conspicuous, heavily sclerotised subtriangular process; uncus slender and a bit knobby, with feeble dorsal crest before apical, recurved hook; tuba analis with long, narrow sclerotised scaphium. Phallus distally arched and with shortly bilobed coecum, vesica with small bilobed, minutely scobinate corpus from which two main diverticula branch, one forward projected that is long and wide tubular and the other opposite, approximately half as wide and half as long as the former, both tipped by stout single cornuti; in addition, one lobe of central corpus pro- duces a swelling terminated by small cornutus.

Material examined. Type material. [ Papua New Guinea: Morobe Province]: Holotypus: ♂, Bismarck Archipelago, Rook Isl. [= Umboi, Siassi], July 1913, A.S. Meek, NHMUK010918649 , in NHMUK (Fig. 11) ;

Paratypus: ♂, same collecting data as holotype, in NHMUK .

Distribution. So far known only from Rook Island (= Umboi, Siassi), lying approximately half-way between the

Huon Peninsula of New Guinea and New Britain ( Fig. 76 ). Possibly also present or replaced by a close relative in the latter island (see entry below).

Etymology. The species is named after the Russian corvette “Vityaz”, which inspired the name of the sea strait (“Viti- az”) that separates New Guinea from the island(s) where the new species occurs. The name is a noun in apposition.

Diagnostic remarks. The new species is looking externally like P. subtracta sp. n., P. togutila sp. n. and P. yaleyambae sp. n. but, contrary to these, sports yellow androconial pencils on male pro- and mesotibiae, which is a feature shared with P. cyanocraspis . Always in the male sex, the third joint of labial palpus is twice as long as in subtracta and yaleyambae , less so distinct with respect to togutila . In the male genitalia, P. vityaz sp. n. can easily be distinguished from all other members of the sumatrana -group by the shortest saccular lobes, while as regards the valval outline it is most similar to P. lecerfi stat.n., from which however it can be separated by the saccular lobes and by the even broader cucullus with much thicker, thumb-like apical process and the wider, less narrowly elongated juxta with stout apical process of the right plate. The phallus sheath of P. vityaz does not terminate into awl-like point and can be therefore confused only with that of lecerfi and togutila , both very different in the configuration of vesicae. Similarities and distinction from a population in New Britain are discussed below.

Taxonomic remarks. This species is described on the ba- sis of two males from Rook Island (= Umboi, Siassi) but it is likely present more to the east in the Bismarck Archipelago or substituted by a close relative which we refrain to describe here, pending upon more material to become available (see next entry).

Platyja sp. ( vityaz sp. n. or close) (Fig. 12)

Figures

Fig. 76 – Distribution of species of the Platyja sumatrana-group (populations from New Britain and Rook Island [= Umboi, Siassi] combined as vityaz s.l.; see explanation in text).