The Leafhoppers and Froghoppers of Australia and New Zealand (Homoptera: Cicadelloidea and Cercopoidea)
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AUSTRALIAN MUSEUM SCIENTIFIC PUBLICATIONS Evans, J. W., 1966. The leafhoppers and froghoppers of Australia and New Zealand (Homoptera: Cicadelloidea and Cercopoidea). Australian Museum Memoir 12: 1–347. [31 December 1966]. doi:10.3853/j.0067-1967.12.1966.425 ISSN 0067-1967 Published by the Australian Museum, Sydney naturenature cultureculture discover discover AustralianAustralian Museum Museum science science is is freely freely accessible accessible online online at at www.australianmuseum.net.au/publications/www.australianmuseum.net.au/publications/ 66 CollegeCollege Street,Street, SydneySydney NSWNSW 2010,2010, AustraliaAustralia THE AUSTRALIAN MUSEUM, SYDNEY MEMOIR X I I The Leafhoppers and Froghoppers of Australia and New Zealand (Hornoptera: Cicadelloidea and Cercopoidea) BY J. W. EVANS* Published by order of the Trustees Sydney, 1966 * 47 Bundarra Road, Bellevue Hill, Sydney, N.S.W., Australia G 2690-1 Registered in Australia for transmission by post as a book SYDNEY: V. C. N. BLIGHT, GOVERNMENT PRINTER, 1966 Contents Part I BIOLOGY. DISTRIBUTION AND EVOLUTION Page Introduction . 5 General characteristics . .. 7 Relationships with other Hornoptera . .. 8 Biology . .. 8 Plant associations . .. 8 The Australian fauna . 9 The New Zealand fauna . 10 The Faunas of New Guinea and New Caledonia Zoogeography . Distribution . Evolution . Abundance . Economic si-gnificance . Some research suggestions . Collecting methods and collections . Part I1 SYSTEMI~TICS Morphology . Characters distinguishing the Cicadelloidea and Cercopoidea The Families of the Cicadelloidea . Classification . Eurymelidae . Cicadellidae . Membracidae . The Families of the Cercopoidea . Cercopoidae . Aphrophoridae . Machaerotidae . Acknowledgements . List or new names . References . List of New Zealand Cicadelloidea and Cercopoidea . Index . PART I BIOLOGY, DISTRIBUTION AND EVOLUTION Introduction Although the insect faunas of Australia and New Zealand are of remarkable interest, there are very few works which deal in a comprehensive fashion with particular groups. Neither are there, with few exceptions, and these relate especially to certain families of Coleoptera and Lepidoptera, reliably named collections available in Australia or New Zealand, which are in any way representative. This means that insect identification within Australia and New Zealand may present considerable difficulties unless insects are well known, or belong to groups being studied by an experienced and helpful specialist. This work deals with two related groups of medium-sized Homoptera, which in most entomological text books are regarded as three groups and which are usually covered in a few short paragraphs. These insects present many problems of interest from the point of view of evolutionary development and geographical distribution; and, as well, include forms of some economic significance. For a period of 35 years the writer has studied two of the comprised families (Cicadellidae and Eurymelidae) and has published many papers on various aspects of their bi~lo~gy,morphology and systematics. These papers are scattered in numerous journals and much of the information in them is now out of date. The principle purpose of this work is to present under one cover such knowledge as the author has acquired of these groups of leafhoppers as they occur in Australia and New Zealand in the hope that it will aid identification of the majority, and perhaps, also, create sufficient interest to lead to their much-needed further study. In order to make it more comprehensive, the Membracidae and Cercopoidea are also included, and brief mention is made of the leafhopper faunas of New Guinea, New Caledonia and Lord Howe Island. It is to be regretted that the day of the active amateur would seem to be nearly over, as such have in the past contributed very greatly to entomological knowledge. Their passing would not be of such great moment if their place was being adequately filled by prorrssional workers, but this is far from being the case. Many who might wish to take an interest in systematic studies are sometimrs deterred at the outset by the burden of literature which, as an initial step, needs to be referred to and understood. This certainly is often a formidable obstacle but it is unavoidable. Once, however, it is overcome, such studies can provide a continuing and expanding interest. While a geneticist may have the satisfaction of working in a field which lies in the vanguard of the advance of knowledge of the mechanics of evolution, a systematist can make a contribution to an understanding of some of the factors which have made evolutionary change possible. In addition, a systematist is often best able to appreciate the significance of such changes. Throughout this work the aim has been followed of endeavouring to make identification as simple as possible and this is the reason for the abundance of illustrations. Nevertheless, in some genera, especially among those which have a cosmopolitan distribution, species recognition will be found to be difficult. This is partly due to lack of clear-cut differentiating characters, but also because critical studies have not been made owing to lack of adequate material. Were publication to have been delayed until such time as it might have been found possible to deal with every group on a uniform basis, and in an equally comprehensive fashion, then it would never have taken place at all. Because of the desire to produce a work which is practical and helpful a policy of '6 lumping" has been adopted. An alternative course would have meant, for example, that instead of a single species being recognized in the genus Stenocotis StB1, thirteen would have been needed to be accepted. In this genus, as well as there being considerable differences in size and in colour pattern, sexual dimorphism also occurs. The reason for the "lumping" in this instance is that the sexes have not been correlated and the male genitalia of all the several colour forms examined are approximately identical. Another example is to be found in the genus Eurymela Le Pelletier and Serville, where no less than g names have been sunk under the specific names of E. distincta Signoret and E.fenestrata Le P. & S. In this instance, the size range of the various forms is inconsiderable and sexual dimorphism lacking but the various colour combinations are so numerous, many more than the eleven which have been named, that to give each of them specific or even sub-specific status, would, in the present state of knowledge, result in needless complications. Another reason for recognizing only two instead of several species is that the male genitalia of all the various colour forms show no marked differences in shape. Very little is known about the geographical ranges or the food plant associations of the various forms in the two genera mentioned, and it is possible that the policy of "lumping" which has been followed may mean that specific status has been denied to representatives of some populations of leafhoppers, which might merit it were the facts of their biology better known. It is also possible that, on the basis of differences of male genitalia, some forms may have been incorrectly considered as distinct species. Miiller (1958) has shown how environmental and seasonal factors may influence the shape of the aedeagi in Euscelis spp. and doubtless similar occurrences are widespread within the Homoptera. While the category of a species has some flexibility, since a "species" may include representatives of populations which are not entirely homogeneous, species nevertheless have some degree of approximate equivalence. This is far from being the case with higher categories, and genera, tribes, sub-families and families within a single super-family are by no means always of corresponding status. Within a group which has undergone its evolutionary divergence in a restricted geographical area, there is, in most instances, no difficulty in the selection of genera. This is because, unless they are monotypic, they are merely assemblages of related species which are separated from other such assemblages by some distinctive morphological characteristic shared in common. In other instances it is not so simple and the determination of the limits of genera is a matter for personal judgment. While in present-day systematic papers a certain amount of quantitative data is frequently presented, personal judgment remains all important. Such judgment, which is based on a critical evaluation of the factors available for study, depends in part on a knowledge of comparative morphology, but above all on insight based on knowledge, experience and understanding. A critic who has not himself undertaken systematic studies may be surprised to note that some of the specific names which have been sunk as synonyms are of insects described by the author. In other words that he has committed the seemingly flagrant error of describing the same species more than once! The explanation is that with increasing knowledge, based on longer experience, views on the criteria which separate species in certain genera may change. Some 619 species are dealt with in this work. This number is not only c!early considerably less than the actual number of species of cicadelloids and cercopoids existing in Australia and New Zealand, but it is also less than the number available to the author for description. Some species have not been described because of inadequate material. Others, because it is considered that their description would serve