Dysaethria walkeri sp. n.
11-12mm. The wings are a warm, slightly brownish
forewing with a fine, only slightly flexed postmedial and a definite but
punctate antemedial. The facies resembles that of D. conflictaria Walker
comb. n. (S. Moluccas), to which it is closely related, particularly in
the stronger but diffuse dark brown shade on the hindwing that runs through the
anterior side of the postmedial angle obliquely to the more posterior of the two
tails. The forewing fasciation is stronger than in conflictaria. The male
genitalia are close to those of conflictaria, having, along with the next
two species, a central process to the uncus, with the more basal of the two
lateral pairs of processes represented by vestigial, rounded lobes. The more
distal pair is absent in conflictaria and its closest relatives. The
valve is distally divided, though unequally, with the more interior part,
associated with the transtillar bridge, much shorter. The transtillar bridge
also has a pair of ventrally directed arms, in conflictaria and allies
forming an H-shaped structure. The Bornean species has the central process of
the uncus robust, somewhat triangular (rounded in conflictaria). The
interior process of the valve and the ventral arms of the transtillar bridge are
very much shorter, together about half the length of the valve rather than
two-thirds. The ventral margin of the valve is indented slightly just beyond the
apex of the sacculus. A further species in this group from Sulawesi (slide 420)
has the uncus rounded, the interior distal process of the valve acute, and the
lower arms of the transtillar bridge flexed out at right angles. D. perpolita
Warren comb n. (Banda Is., Sulawesi) is a smaller species with more delicate
male genitalia than the three species just discussed: the H-shaped structure is
relatively small, its arms outcurved, and the aedeagus vesica contains a single
long cornutus. A cornutus is present in the other Sulawesi species, but absent
in conflictaria and walkeri.
Holotype . SARAWAK: Gunung Mulu Nat. Park, R.G.S. Exped. 1977-8 (J.D. Holloway
et al.) Site 20, Mar.-Apr., W. Melinau Gorge, 150m. 422577, FEG 3 kerangas,
BM uraniid slide 290.
Paratypes: 1 as
holotype; l, 2 same general data as holotype but sites 12 (200m, G.
Mulu), 15 (1000m, G. Mulu) and 26 (1200m, G. Api); 1 (slide 370) BRUNEI: 3m,
Seria, secondary and coastal veg. 16.11.79 (Lt. Col. M. G. Allen); 1
BRUNEI: 15m, Daerah Belait, Badas, swamp forest, 27 Feb 82 (Lt. Col. M.G.Allen);2
BRUNEI: Seria, 5m, 9 & 16.iv.1981 (T.W. Harman); 2 BRUNEI:
200m, 2.iii.1982 (T.W. Harman).
Geographical range. Borneo, ?Sumatra. (ZSM; not dissected).
Habitat preference. The species is infrequent, recorded from a range of
forest types from the lowlands to 1200m, with some preference for forest on
acid, nutrient-poor soils when in the lowlands.
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