View Image Gallery of Subfamily Thyatirinae

This subfamily consists of robust, rather noctuid-like moths with relatively narrow forewings. The forewing pattern is also reminiscent of that of noctuids with, in some species, stigmata that resemble the noctuid reniform and orbicular. Unlike other drepanids and a high proportion of geometroids, the hindwing is only weakly patterned, if at all, and generally paler than the forewing. There is usually a distinctive wing-thorax coupling mechanism where aculeate patches on either side of the thoracic metascutum interact with similar patches beneath the forewing (Scoble & Edwards, 1988).

The tympanal organs are typically drepanoid (Scoble & Edwards, 1988; Scoble, 1992 and references therein), and the well-developed frenulum is sometimes clubbed apically. The male antennae are usually filiform, slightly lamellate. The wings have drepanoid venation, the forewing usually with an areole, the hindwing with Sc+R1 converging with Rs briefly just beyond the cell.

The male genitalia are characterised by a strong pair of socii flanking the uncus. The valves are usually simple, sometimes with angular projections from the ventral margin. The aedeagus has a characteristic curved spine-like process (Haken, or hook, of Werny (1966)) at its apex, and the ductus ejaculatorius is inserted significantly more distally than in other drepanoids, often beyond the midpoint of the aedeagus tube. The gnathus is absent.

The female typically has a longitudinal band-like signum with outwardly directed spines in the basal part of the ovate bursa, often with one or two small satellite signa (illustrations in Werny (1966)).

The larva has anal prolegs developed. There are secondary setae in some species, and the body segments sometimes bear tubercles and forked protruberances (Scoble, 1992).

The subfamily is most diverse in the Asian subtropics and through the Palaearctic, though with the greatest diversity occurring in the eastern part, particularly China and the eastern Himalayan ranges (Werny, 1966). Some genera extend into the New World. There is weak representation in Africa (Watson, 1965; Lane, 1973). A few genera, mostly montane, extend into Sundaland and Wallacea, with outlying species and the genus Habrona Bethune-Baker in the mountains of New Guinea (Holloway, 1986b).

The unusual Australian genus Hypsidia Rothschild was recognised as drepanoid by Scoble & Edwards (1988), who reviewed the species. They were reluctant to associate the genus with the Thyatirinae, being unconvinced of the homology of the pair of arms articulated between the uncus and tegumen with the thyatirine socii, or the presence in Hypsidia of weak aculeate patches on the thoracic metascutum and clubbing of the frenulum. Ocelli are present in one species group. The ductus bursae is unusually spiralled, a feature probably unique within the drepanoid/geometroid complex. There is a single signum in the ovate bursa in a similar position to that of thyatirines, but rounded, with general scobination. However, several further features may indicate the genus is thyatirine: presence of a hook on the aedeagus apex; a relatively distal insertion of the ductus ejaculatorius; ornamentation of the ventral margin of the valve; robust, noctuidlike build and forewing shape; reduced marking of the hindwings.

The thyatirine fauna of Sumatra, with eight species in six genera (Kobes, 1985), is more diverse than that of Borneo. All Bornean species occur there. In addition there is a second Tethea Ochsenheimer, T. consimilis congener Roepke (= diehli Werny), Takapsestis sumatrensis Gaede, Habrosyne obscura Roepke and Habrosyne sumatrana Werny. Neogaurena grisescens Roepke (Java) is a synonym of T sumatrensis Gaede, Neogaurena therefore becoming a synonym of Takapsestis Matsumura, syns. n..

>>Forward <<Return to Contents page

Copyright Southdene Sdn. Bhd. All rights reserved.