This
part of The Moths of Borneo includes accounts of the families Cossidae,
Metarbelidae, Ratardidae and Limacodidae. It is the first part of the series and
therefore an appropriate place to include a key to world macrolepidopteran
families that will serve the whole series and complement An Introduction to
the Moths of South East Asia by Barlow (1982).
All
‘macrolepidoptera' belong to the Suborder Ditrysia, members of which have the
venation of fore- and hindwings dissimilar and possess a female genital opening
(ostium) on sternum 8 that is separate from the ovipositor on sternum 9.
This part contains the families attributed to the superfamily Cossoidea
by Brock (1971), though Common (1970) placed the Limacodidae in the Zygaenoidea.
It is not feasible in this work to throw any further light on this disagreement
but the reader should be aware that the higher classification of the Lepidoptera
is still in a state of flux and changes must be expected in the light of future
work.
The families treated here, with the exception of the Ratardidae, all
contain many species of economic importance, with wood, stem and bark borers in
the Cossidae and Metarbelidae and numerous serious defoliators of plants of
economic importance in the Limacodidae.
Most of the material referred to in this series was accumulated during
three major surveys, two by the author in the Kinabalu and Mulu National Parks
of Sabah and Sarawak respectively, and the other over a period of years by Lt.
Col. M.G. Allen and associates in Brunei. Details of the first two surveys,
accounts of the various localities sampled and analyses of the ecology and
habitat preference of the species can be found in Holloway (1970, 1984b).
Accounts of the Brunei collecting localities are given by Allen (1981),
Harman (1981) and Cassidy (1982). There is some inconsistency in the vegetation
zones recognised in these references and on label data quoted for specimens in
the main text. The broad categories referred to by Holloway (1984b) will
be adopted here.
KEY TO THE FAMILIES OF MACROLEPIDOPTERA AND TO SOME SUBFAMILIES
Although this series is restricted to macrolepidoptera found in Borneo,
a key to all world macrolepidoptera families is presented below as there is no
guarantee that some at least of the non-Oriental groups will not ultimately be
collected in South East Asia. Families occurring in Sundaland are indicated by
heavy type, and macrolepidoptera by capitals.
The key is a modified version of one used in the annual Commonwealth
Institute of Entomology taxonomy courses and it is hoped that a key to all
Lepidoptera and notes on the families of economic importance can be published as
a manual in the near future.
The key has been constructed with a view to enabling an inexperienced
worker to place most specimens he will encounter to family in most cases.
Readily appreciable characters have been used where possible though
harder and more reliable characters may be available; the latter, such as
characters of thoracic-abdominal articulation, usually require preparatory work
and dissection that may partially destroy the specimen. Even so, some of the
characters used here are hard to appreciate. The tympanal organs in Noctuoidea
and Geometroidea are best studied initially in fresh material which is malleable
and where the tympanum shows up clearly as a nacreous or skinlike opaque
membrane.
Characters of wing venation can be studied better if a wetting agent
such as absolute alcohol or ethyl acetate is applied. The wings then increase in
transparency and the veins can be seen if the wing is illuminated from behind
and viewed under a microscope.
A number of the venation characters used recur from superfamily to
superfamily and may reflect differences in flight mode and mechanics rather than
any phylogenetic relationship. For example M2
may arise from nearer
the cubital angle of the cell of each wing than the radial angle more frequently
in deep-winged moths, and from nearer the radial angle in narrow-winged moths.
Similarly, antennae with swollen, clubbed or hooked tips occur in a wide
range of families, such as Sphingidae, Sematuridae, Noctuidae (Agaristinae,
Cocytiinae), Arctiidae (Ctenuchinae), Castniidae, Zygaenidae, Papilionoidea and,
slightly, Callidulidae. The common factor is the day- flying habit and one must
presume that the possession of a pair of solid objects anterior to the eyes
provides some sort of visual information: the function could be for
range-finding or measuring. This is evidently a case of evolutionary
convergence.
Opinions differ on superfamily divisions and also on the status in the
hierarchy of some groups or their assignation to higher categories (Brock 1971;
Common 1975; Minet 1983; Heppner 1984a). This key tends to follow broad
concepts, i.e. to ‘lump' rather than ‘split'. Superfamilies may be
identified by the ending -OIDEA, families by the ending -IDAE and sub- families
by the ending -INAE.
There are very few keys available that will permit assignation to family
of a lepidopteran from any part of the world. Common's (1970) key concentrates
on the Australian fauna. That by Janse (1932) is much more comprehensive but the
familial nomenclature requires considerable updating. This key draws from
several sources and includes observations drawn from the experience of the
author, primarily from the Old World tropical fauna. It is no doubt far from
perfect and the author would be grateful for indications of error and
suggestions for improvements.
Click here for a guide to wing venation for reference when using the key .
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