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Amata Fabricius

Type species: passalis Fabricius (Sri Lanka and India).

Synonyms: Syntomis Ochsenheimer (type species phegea Linnaeus, Europe); Coenochromia Hübner (type species passalis Fabricius); Hydrusa Walker (type species bicolor Walker, Australia); Asinusca Wallengren (type species atricornis Wallengren, S. Africa); Buthysia Wallengren (type species sangaris Wallengren = huebneri Boisduval, Java); Callitomis Butler (type species syntomoides Butler, Kashmir). The genus Leopoldina Hering (type species leopoldi Hering) is probably based on a synonym of Amata sperbius Stoll.

This genus, for which the Palaearctic taxa were reviewed by Obraztsov (1966), is best defined on genitalic characters, as it exhibits great variety in wing pattern and abdominal banding.

The genitalia are asymmetric in both sexes. In the male the tegumen has prominent lateral lobes. The valves have strong, curved, asymmetric processes from the base of the costa and are themselves asymmetric. The aedeagus vesica contains a row (or rows if it has more than one lobe) of small cornuti, some of which can become very long. In the type species of Hydrusa and Buthysia there is no asymmetry, and lobes to the tegumen are lacking. Both species have the valve apex produced into a setose process. Despite extreme facies differences (H. bicolor lacks patches or windows on the wings) the species would appear to be related, and the genera are best retained in synonymy with Amata as they possess the aedeagus vesica ornamentation that characterises that genus.

In the female genitalia the ostium is set asymmetrically between the eighth and seventh tergites.

The larva of the type species has been described by Sevastopulo (1941) and Bell (MS). The mature larva is cylindrical, constricted at segment margins, each segment bearing typical arctiid verrucae with tufts of long hairs. The head is reddish orange but the body is deep blackish purple. The hairs on the verrucae are a mixture of feebly pectinate black ones and strongly pectinate grey ones, giving the larva a generally grey appearance.

Rammert (1987) described defensive glands in European Amata, associated with the large dorsal verrucae on each segment. These rupture when the larva is attacked, releasing a noxious fluid stored in a subcutaneous cavity.

The host-plants of A. passalis are Ipomoea (Convolvulaceae; Bell (MS)), Cajanus (Leguminosae; CIE records), Dahlia, Cosmos (Compositae; Sevastopulo (1941)) and Santalum (Santalaceae; Browne (1968)), but Bell noted marked cannibalism amongst the larvae.

The pupa is in a slight cocoon of brown silk, interwoven with a few of the larval hairs, though most of these are not shed.

The egg is white, spherical, slightly flattened at the base, unsculptured, and laid in large batches.

Bell (MS) noted that A. passalis males sembled upwind to freshly emerged females. He also reared A. cyssea Stoll and A. elongata Hampson, the larvae of both of which were moss or lichen browsers, found on tree-trunks or walls. However, Browne (1968) referred to A. cyssea as a polyphagous crop pest.

There are numerous species in Borneo, here grouped loosely on the basis of facies into: a white-spotted group, the posterior distal spot of the forewing single (wallacei Moore to pleurosticta Hampson); a yellow spotted group, usually with the most distal of the posterior pair of forewing spots set at an angle and wedge-shaped, and the posterior patch of the distal pair divided by a vein, the hindwing broadly basally yellow and often modified in shape in the male (egenaria Walker to kinensis Hampson); a slender montane group, often with elongate markings (pseudextensa Rothschild to mjobergi Talbot); a robust, extensively transparent group with broad, angled valve apices in the male genitalia (cantori Moore, pryeri Hampson, symphona Swinhoe), associated with a number of other more transparent species.

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