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it 1. STUDIES ON THE TAXONOMY OF THE ELYDIDAE 41TH SPECIAL REFERENCE TO THE SUBFAMILY LEPTOCORISINAE (HETEROPTERA) by Imtiaz Ahmad, M.Sc. (Karachi) A thesis submitted for the degree of Doctor of Philosophy in the Faculty of Science, University of London. Imperial College of Science and Technology, Field Station, Silwood Park, Sunninghill, Ascot, Berkshire. October, 1963. 2. ABSTRACT Taxonomy of the family Alydidae has been in confusion in the past. Some of the recent authors (e.g. China and Miller, 1959) have not accepted its family rank and its lower categories have been virtually ignored. During the present studies the abdomen and its appendages (the genitalia) of the various representatives of the family Alydidae have been examined to evaluate their importance in the classification of higher and lower categories. Prior to this revision the subfamily Leptocorisinae Stk (Div. Leptocorisaria of the subfamily Alydina) contained eight genera and thirty eight species including major rice pests of the Far East. There was confusion over the identities of many species and since Stk (1873) no world wide revisional work had been undertaken and in his work only fourteen species (including some synonyms) ware covered. During the present studies three new tribes, one new genus, two new subgenera, twenty one new species have been described and one species, on account of its homonymy, has been renamed. Stenocoris Burmeister (1839) (subgenus sensu Stal, 1873) has been given generic rank and has been separated from Leptocorisa Latreille 1829, an application has been made to the International Commission on Zoological Nomenclature to supress Leptocorixa. Rhabdocoris Kolenati 1845 (subgenus of Leptocorisa Latreille sensu Stk, 1873) has been synonymised with Leptocorisa. The undescribed misidentified type species of the subgenus Erbula has been renamed and described and a request has been made to the International Commission on Zoological Nomenclature to 3. use its plennary powers to retain the subgeneric concept unchanged (see Appendix 2). Nine previously described species have been considered synonyms, whilst four of the species regarded as synonyms by earlier workers have been reinstated. Three of Bergroth's genera, formerly included in the Leptocorisinae have been transferred to the tribes of the subfamily Coreinae (sensu Stk 1873). They have been redescribed and figured and two new species described from within them. 4. TABLE OF CONTENTS Page INTRODUCTION 9 MATERIALS AND METHODS 11 PART I. THE MORPHOLOGY OF THE ABDOMEN WITH SPECIAL REFERENCE TO THE GENITALIA AND ITS BEARING ON CLASSIFICATION 14 Introduction 14 Morphology 15 Pregenital region 15 Genital region in male 17 Post genital region in the male 22 Genital region in the female 22 Post genital region in the female 26 Abdominal characters of Alydid subfamilies:Alydinae 26 Micrelytrinae 26 Leptocorisinae 27 PART II. TAXONOMY OF LEPTOCORISINAE (ALYDIDAE) 38 Review of the literature 38 Family Alydidae 43 Key to the subfamilies 44 Subfamily Leptocorisinae 45 Key to the genera 47 Tribe Leptocorisini 48 Genus Stenocoris 49 Key to the subgenera 51 5. Page Subgenus Pseudoleptocorisa subgen. n 52 Stenocoris (Pseudoleptocorisa) erratica 53 Subgenus Erbula 56 Key to the species 58 S. (E.) annulicornis 59 S. (E.) distinguenda 63 S. (E.) elegans 66 S. (E.) similis 69 S. (E.) southwoodi 71 S. (E.) stali 76 Subgenus Stenocoris s. str 79 Key to the species 80 S. africana 83 S. americana 86 S. apicalis 88 S. braziliensis 91 S. claviformis 93 S. ethiopis 96 S. maculosa 98 S. pallida 101 S. phthisica 104 S. sordida 108 S. tipuloides 111 6. Page S. v—nigrum 115 Subgenus Oryzocoris 118 S. (O.) fabricii 121 S. (O.) filiformis 124 S. (0.) furcifera 128 Genus Leptocorisa 131 Key to the species 134 L. acuta 139 L. biguttata 145 L. chinensis 149 L. costalis 153 L. discoidalis 157 L. lepida 160 L. luzonensis 162 L. luzonica 165 L. oratorios 168 L. palawanensis 174 L. pseudolepida 177 L. sakdapolraki 180 L. solomonensis 182 L. tagalica 185 L. bipunctata Costa 188 L. burmeisteri Montrousier 188 7. Page Genus Mutusca 190 Key to the species 191 M. brevicornis 192 M. prolixa 196 Genus Bloeteocoris 199 Key to the species 200 B. inflexigena 201 B. meridianus 203 B. minutus 206 Tribe Noliphini 209 Genus Lyrnessus 209 L. geniculata 211 Genus Cosmoleptus 214 Key to the species 215 C. bakeri 216 C. limbaticollis 218 C. sumatranus 220 Genus Noliphus 222 Key to the species 223 N. annulipes 226 N. discopterus 229 N. erythrocephalus 231 N. insularis 234 N. papuensis 236 8. Page N. spinosus 239 N. timoris 243 Check list of Leptocorisinae 246 Zoogeography and phylogeny, 251 PART III. DICRORYMBUS, XENOCERAEA AND PROCAMPTUS. THREE OF BERGROTH'S GENERA FORMERLY INCLUDED IN LEPTOCORISINAE 422 Genus Xenocerae 426 Key to the species 428 X. bakeri 428 X. philippianis 430 Genus Dicrorymbus 432 Key to the species 433 D. nigridens 434 D. luzonensis 437 Genus Procamtus 439 P. segrex 441 SUMMARY 454 ACKNOUEDGMENTS 458 REFERENCES 461 APPENDIX 1 474 APPENDIX 2 480 9. INTRODUCTION Leptocorisinae St21 is a subfamily of the coreoid family Alydidae and contained prior to the present revision eight genera and thirty eight species, including a number of important rice pests of the Indochina, Malaya and Australian Sub region. In the whole subfamily, there has been confusion and uncertainty over the identification of species. For example China (1930) in "Insects of Samoa and other Samoan terrestrial Arthropoda" expressed his doubts on the specific identity of Noliphus discopterus Stale and stated that perhaps it was a local race of N. insularis Still. Villiers (1955) formulating keys for the species of French African Stenocoris Burnister then regarded as a subgenus of Leptocorisa Latreille, suggested the synonymy of S. (Erbula) distinguenda Blike, 1937 with S. (E.) elegans BlBte, 1937. A morphological study of the abdomen and genitalia of various representatives of the subfamilies within Alydidae has been carried out in order to understand their significance in classification. During the present work the forms of male and female genitalia have been found to be of great taxonomic value, clearly separating the species. The structure of female genitalia and in particular the shape of spermatheca have suggested that oriental and Australian species of Leptocorisa Latreille, 1829,(previously considered under the subgenus Rhabdocoris Kolenati, 1845) should be separated from Ethiopian, Nearctic and Neotropical species (previously considered under the subgenera Stenocoris Burmeister, 183% Erbula Still, 1873 and Leptocorisa 10. s. str. 5ta1, 1873). Other characters found to be of value are as follows: (a) The form of head, its colouration and its sutures. (b) Length and colour of antenna' segments. (c) Size of rostrum and length of the components. (d) The comparison of the interocellar distance with the distance between an ocellus and an eye (in both cases including the diameter). (e) Length, breadth and the colour of pronotum. (f) The posterior margin of seventh abdominal tergum in the male and the seventh abdominal sternum in the female. (g) In the male the shape of the pygophore, claspers, thecal appendages and the form of vesica when fully everted. (h) In the female the first gonocoxae, first gonopophyses, second gonopo- physes and spermathecal shape. Three Bergroths genera Dicrorymbus, Xenoceraea described within Leptocorixaria near Mutusca Stgl 1865 in 1918 and Procamptus also described under Leptocorixaria in 1925 have been excluded from subfamily Leptocorisinae and have been transferred with two new species in the tribes Dasynini Brown 1955 and Procamptini trib. n. of the subfamily Coreinae (sensu Stgl 1873). 11. MATERIALS AND METHODS Although the species of the subfamily Leptocorisinae are represented in all the zoogeographical regions of the world, they are cottpletay absent from European countries. Thus it was not possible to collect material in the field and to compensate a large quantity of material (about 10,000 specimens) of the group was borrowed from major museums, and personal collections from all, over the world. (A complete list of these museums and those who lent their personal collections is given under Acknowledgments). Freshly prepared materials (in 70% alcohol) were also obtained by the courtesy of Dr. J.W. Evans (Australian Museum, Sydney) and Dr. G. Rothschild (Sarawack Agricultural Institute). Every effort was made to examine and dissect the genitalia of the holotypes of all species (including those believed to be synonyms). In the great majority of cases it has been possible to do this or to obtain authorat— ive information about the loss or damage of the original holotype, so necessitating the designations of neotypes. Lectotypes have also been designated from syntypes in a few cases. A full account of the circumstances and action taken is given for each species under the subheading `taxonomic note". Male and female genitalia were dissected after softening the tenninalia in 10% Potassium hydroxide solution. It was found easiest to inflate aedeagus in water just after it was softened. The form of the genitalia was considered to be a reliable character for distinguishing species as little intergradation was found between its form in two A3lied 12. species and within a species as many as twenty five from widely separated localities were dissected and found to have similar genitalia. Large structures were stained in 1% acid fuchsias in acetic acid and were examined in Methyl benzoate, cedarwood oil or creosote. All the drawings were made by using a squared eye piece under a binocular microscope from the type specimen when available. Genital structures were preserved in glycerine in small tubes and were pinned with the insects. It has been attempted to make the descriptions as uniform as possible and known species have also been redescribed as many of the existing descriptions were inadequate and omitted a detailed account of the genitalia, An measurements were taken by using micranillimetre slides. When available five specimens of each sex were measured and extreme ranges have been given.