Unassigned, mostly apomorphic genera
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Oeonistis Hübner

Type species: entella Cramer, India.

Synonym: Philagria Kirby (type species entella Cramer).

This genus contains four more or less allopatric species ranging from the Indian Subregion to Samoa, Tonga and Queensland. All species (except lifuensis Rothschild where markings are reduced) have a similar distribution of blue-black on the forewing, particularly the stepped medial bar and the more irregular submarginal zone, the apical ellipse of yellow being similar to that of Monosyntaxis females. The venation is illustrated in Fig 1g.

Fig 1g: Oeonistis entella Cramer

The male genitalia have a reduced saccus as in Monosyntaxis and a similar aedeagus, but the valves are more elongate, the saccular process robust, broad, not falcate, apically setose or spined. Two of the four species (entella Cramer, delia Fabricius) have a furca-like structure, particularly well developed in delia.

The female genitalia have a short, sclerotised ductus, sometimes with a colliculum, and an elongate, pyriform corpus bursae with a single, strong, scobinate signum centrally at the widest part.

The New Caledonian and Loyalty Island species, lifuensis Rothschild, was recognised as distinct from what was then considered to be the widespread entella Cramer by Viette (1950), who illustrated its genitalia with those of delia Fabricius stat. rev. Dissection now indicates that entella is in fact a complex of three species.

True entella (syns. convoluta Fabricius, entelliola Hübner) appears to be restricted to S. India and Sri Lanka. The male genitalia are distinguished from those of altica Linnaeus by an acute but setose apex to the saccular process and a pair of prominent, dark, finely setose ear-like lobes in a furca-like structure.

The Bornean species is altica Linnaeus, with China as type locality (Mikkola & Honey, 1993), having similar male genitalia to entella but lacking the furca lobes and having the apex of the saccular process of the valve rounded, with a serrate row of short spines round its extremity.

The third species, delia Fabricius (syns. ceramensis Vollenhoven, splendens Lucas, braeckeli Debauche), ranges from Sulawesi eastwards to New Caledonia, Samoa and Tonga, and is characterised by long furcal arms and a broad, biangular saccular process in the male genitalia. The type material of delia consists of two unspread females in the Banks Collection in BMNH, with the type locality ‘Insula Amsterdam’. There are several contenders for this locality, including the ecologically unlikely one in the S. Indian Ocean that still bears this name. Others listed in gazetteers were located off Sri Lanka and Java, and as a European name for Tongatapu in Tonga. Dissection of one syntype (BM arctiid slide 4911) revealed it to be damaged internally but to have sufficient of the sterigma and structures posterior of it to show that it had a flocculent, ring-like structure at the distal end of a pleat running back from the sterigma. This is a feature of the eastern widespread species (e.g. seen in a specimen from Vanuatu; slide 4829), hence the Tongan option for the type locality is probably correct.

The early stages of entella have been described by Hampson (1900) and Bell (MS). Hampson described the mature larva as having a reddish brown head, and the skin of the body ochreous, mottled with black dorsally and brown elsewhere. The tufts of setae on verrucae are grey and brown, those on T1 directed forwards. The dorsal verrucae on T2 have very long setae, and those on T3 arise from a crimson wart and are also long. The dorsal tufts of abdominal segments are shorter, arising from orange warts, except on A4 where the warts are again crimson. There is a prominent dorsal tuft on A8 arising from a large wart; the lateral tufts tend to be long and the sublaterals short.

The eggs (Bell, MS) are laid in batches of over one hundred on the underside of leaves, more or less in rows and narrowly separated one from another. They are round, with hexagonal dents in irregular concentric circles around the micropyle.

Hampson (1900) noted lichens as the larval food.

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