Pollex (Bilobiana) hamus, Fibiger, 2007

Fibiger, Michael, 2007, Revision of the Micronoctuidae (Lepidoptera: Noctuoidea). Part 1, Taxonomy of the Pollexinae, Zootaxa 1567 (1), pp. 1-116 : 67-68

Pollex (Bilobiana) hamus Fibiger, new species

( Plate 8 , figure 8; male genit. plate 18, figure 6)

Material examined.

Holotype: male, Philippines, Leyte, 5 km E Ormoc, 200 m, 3-11.x.1965, leg. D. Davis, genit. prep. 5684 M. Fibiger. Coll. USNM.

Diagnosis.

Wingspan: 11 mm.

Forewing: relatively broad, dark brown.

Transverse lines: indistinct, black; terminal line marked by black dots between veins.

Reniform: distinct, round, whitish grey, outlined by black.

Fringes: coloured like subterminal area.

Hindwing: very small, unicolorous dark brown, without a discal spot; ventral part of hindwing transformed to a long log-like cylindrical tubeUnderside: unicolorous dark brown.

Male hindleg: covered with prominent, long, black, hair-like scales forming scent brush.

Underside: unicolorous dark brown.

Male genitalia.

Tegumen: narrow.

Vinculum: short, stout.

Saccus: U-shaped, short.

Fultura superior: T-shaped, broad, fused with upper middle part of tegumen and on ventral side fused broadly with juxta-anellus plate; each horizontal arm with a prominent, short, apically blunt, ventrally directed processes.

Valve: shorter than wide.

Ampulla: prominently asymmetrical; left and right ampulla relatively long, equally broad throughout, densely setose with long hair-like setae bent inwards; right ampulla slightly longer and broader.

Pollex : base of left side heavily fused with base of ampulla, narrow, curved, spine-like, longer than ampulla, without setae; right side basally broadest, almost as long as ampulla, with inwardly directed setae.

Digitus: absent on left side; right digitus long, slightly curved, tapered, apically pointed.

Juxta-anellus plate: large, higher than wide, hole for phallus positioned medially in plate.

Phallus: long, curved, slightly tapered towards apex; broadest by ductus ejaculatorius; coecum short and narrow.

Vesica: unarmed.

Differential diagnosis.

P. hamus and the next species P. sansdigit (see below) differ from other species by the log-like structure on the lower part of the hindwing, and the conspicuously asymmetrical male genital armature. In spite of these features, the ventral processes on the fultura superior, the shape of the right digitus, ampulla and pollex, and the shape and the unarmed phallus, place this species firmly into the bulli species-group.

Because of the broad and somewhat rounded forewing, the indistinct cross-lines, the circular reniform, and the ‘apparently’ very small hindwing it makes a wrong determination highly possible, as a Tolpiodes Hampson, 1926 species. However, Tolpiodes – as well as Anachrostia Hampson, 1893 – belong to a little known group of very small species for the moment placed at the end of the huge and paraphyletic Noctuidae subfamily, Erebinae.

Figures

PLATE 8. Figures 1–8. Pollex subgenus Bilobiana species, adults. 1, P. (B.) angustiae, male holotype, Indonesia, Sumatra, Padang, Panjang; 2–4, P.(B.) oculus, male paratype, Philippines, Palawan, Aboabo, male holotype, Philippines, Balabac, Dalawan Bay, and male paratype, with same data; 5, P.(B.) bulli, male holotype, Philippines, Palawan, Brookes Point; 6, P.(B.) taurus, male holotype, Philippines, Mindanao, Cotabata S; 7, P.(B.) schintlmeisteri, male holotype, Indonesia, W Seram, Kamarlan; 8, P.(B.) hamus, male holotype, Philippines, Leyte, Ormoc.