|
SUBFAMILY
BAGISARINAE |
|
Xanthodes transversa Guenée (Plates 2, 10, Figs 32, 47) Xanthodes
transversa Guenée, 1852, Hist.
nat. Ins., Spec. Gen. Lep. 6: 211. Diagnosis. The moth is generally pale yellow. The forewings have narrow, sharply angled, brown antemedial and postmedial fasciae, and a brown marginal shading that is more extensive centrally. Taxonomic note. Two very similar species occur in India and Sri Lanka, as indicated in the section on biology below. The one restricted to this area appears to be undescribed. It differs from transversa in having a stronger longitudinal brown streak at the centre of the forewing; the submarginal fascia is more irregular, closer and more parallel to the postmedial posterior to the angle, rather than divergent as in transversa. The fasciae are generally more zigzag, but finely so. The taxon pseudotransversa Hampson listed by Robinson et al. (2001) is a nomen nudum based on Bell’s manuscript, and probably refers to transversa, given Bell’s confusion of the two species. The forewing facies features distinguishing the undescribed species are also seen in the Australian X. emboloscia Turner, though this has a much larger longitudinal brown wedge. Geographical range. Indo-Australian tropics to Australia and Vanuatu. Habitat preference. Older material seen is from lowland localities or without precise altitude data. Holloway (1976) recorded the species at the Agricultural Research Centre at Tuaran in Sabah, and it has otherwise not been recorded in recent surveys. It is probably a species of open habitats. Biology. Most of the larval descriptions attributed to transversa originate from the Indian Subregion, e.g. Moore (1884‑1887), and Sevastopulo (1939). These authors and Bell (MS) describe a green larva with a greyish white ventrum and a yellowish tinge to the segment margins. On each segment there is an obscure, slightly darker band sloping down backwards from subdorsally to just above the spiracles. There may be orange or yellow spots but no conspicuous black markings. However, it was only Bell who realised that there were two totally distinct types of larva in India. The green one yields the undescribed species distinguished in the taxonomic note above. The larva of transversa is the second type described by Bell and matches that illustrated or described for elsewhere in the wide range of the species: by the author in Peninsular Malaysia (Plate 10); by Sugi (1987) in Japan; by Common (1990) for Australia. The description in the next paragraph is condensed from Bell (MS), though Gardner (1941) described a similar larva from India. The larva is cylindrical from the head to A6, slightly fatter over A4 and A5. Prolegs on A3 and A4 are reduced to smooth, wart‑like tubercles. The head is rather square, shining, and covered with small, glassy, dome‑like tubercles. It is apically green, with a large black spot on the posterior of each lobe and a yellow band down the vertex and six black spots on the frons. The body is dull, smooth, with primary setae only on small chalazae that are white except where on black markings. The colour is a dark grass‑green with a moderately broad canary‑yellow dorsal band, and a similar but duller spiracular band. There are subdorsal black patches on each segment, these divided transversely into two by a line of ground colour. Each segment has its margins with an interrupted black line. The spiracles are brownish‑yellow, rimmed with dark brown or black. The young larvae are threadlike, active, looping prominently. They eat holes in the leaves from the underside. When mature, they are often found stretched on the uppersides of leaves. Pupation is in a cell made in a leaf drawn loosely together with silk that also lightly coats the inside of the cell. The host plants recorded for both species were collated by Robinson et al. (2001): Barringtonia (Lecythidaceae); Abelmoschus, Alcea, Gossypium, Hibiscus, Kydia, Sida, Urena (Malvaceae); Psidium (Myrtaceae); Citrus (Rutaceae); Solanum (Solanaceae); Grewia (Tiliaceae); Boehmeria (Urticaceae). Kuroko & Lewvanich (1993) recorded the species as feeding on Abelmoschus (okra; Malvaceae), Psidium (guava; Myrtaceae) and Solanum (egg‑plant; Solanaceae) in Thailand. The only record that can definitely be associated with the green larva is for Solanum (Solanaceae; Bell); Moore and Sevastopulo did not identify host plants. |
Copyright © Southdene Sdn. Bhd. All rights reserved.