Nachaba transversa Walker,
1863, List Specimens lepid. Insects Colln. Br. Mus. 27: 114.
Chlumetia guttiventris Walker,
 1865, List Specimens lepid. Insects. Colln. Br. Mus. 34:
Chlumetia guangxiensis Wu
& Zhu, 1981, syn. n.
Diagnosis. This species differs from congeners most distinctly in genitalia
characters but also in facies: the forewing submarginal band is broken such that
there are two oblique blocks at its widest zone, on either side of a break one
third from the costa; the reniform is open anteriorly, its distal fine black
border being continued by a line to the costa (displaced in other species as a
rule); there is a dark greyish shading subbasally and between the medial and
postmedial. In the male genitalia the valves are slender, curved upwards, with a
detached short ventral lobe; the uncus is broad, short, polygonal, the saccus is
moderate in breadth. The basal part of the modified male eighth sternite is
shallower than in other species. In the female genitalia the ductus terminates
in a lamella with two elongate scobinate bands, with a separate central
crescent-shaped sclerite dorsally, centrally; the scobinate appendix bursae is
longer than the bursa which arises centrally from the common ductus.
Geographical range. The species is found throughout the Indo-Australian
tropics to as far east as the Solomons.
Habitat preference. Few Bornean specimens have been seen but the species
may be restricted to the lowlands and has been reared from mango.
Biology. Gardner (1948a) described the larva of an Indian species, either transversa
or the new species, brevisigna, described below. The legs and prolegs
are short, the spiracles narrow, the sides of the body parallel. The head and
pronotum are testaceous brown, the head darker; both are black in early instars.
The body is dull violaceous above, greenish below. The skin is finely granulate.
The larva tunnels in young shoots of mango (Mangifera; Anacardiaceae).
Wu & Zhu (1981) recognised that there were two species of Chlumetia
on mango in China but it is evident from their illustrations of genitalia
that they redescribed transversa as new after identifying brevisigna as
transversa. This was probably because the former was observed to
defoliate mango, especially the young leaves, whilst the latter bored into
flower pannicles and young shoots causing wilt. Thus it would appear that the
‘mango shoot borer’ of the literature is almost certainly brevisigna and
The following references are papers on various aspects of the biology,
predators and parasites of the ‘mango shoot borer’ and methods of control.
Tang & Chang (1971); Chahal & Dilbagh Singh (1977); Shahjahan &
Ahmad (1978); Bagle & Prasad (1980); Tandon & Srivastava (1980); Mohite
& Dumbre (1981); Pandey et al. (1981); Tandon & Lal (1983). It is
probable that the species referred to as transversa in this literature is
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