Louisiana State University LSU Digital Commons LSU Historical Dissertations and Theses Graduate School 1967 A Comparative Study of the Hymenopterous Poison Apparatus. Henry Remley Hermann Jr Louisiana State University and Agricultural & Mechanical College Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_disstheses Recommended Citation Hermann, Henry Remley Jr, "A Comparative Study of the Hymenopterous Poison Apparatus." (1967). LSU Historical Dissertations and Theses. 1294. https://digitalcommons.lsu.edu/gradschool_disstheses/1294 This Dissertation is brought to you for free and open access by the Graduate School at LSU Digital Commons. It has been accepted for inclusion in LSU Historical Dissertations and Theses by an authorized administrator of LSU Digital Commons. For more information, please contact [email protected]. This dissertation has been microfilmed exactly as received ® 7-13,989 HERMANN, Jr., Henry Remley, 1935- A COMPARATIVE STUDY OF THE HYMENOPTEROUS POISON APPARATUS. Louisiana State University and Agricultural and Mechanical College, Ph.D., 1967 Entomology University Microfilms, Inc., Ann Arbor, Michigan A COMPARATIVE STUDY OF THE HYMENOPTEROUS POISON APPARATUS A Dissertation Submitted to the Graduate Faculty of the Louisiana State University and Agricultural and Mechanical College in partial fulfillment of the requirements for the degree of Doctor of Philosophy in The Department of Entomology by Henry Remley Hermann, Jr. M.S., Louisiana State University in Baton Rouge, 1965 May, 1967 ACKNOWLEDGEMENTS I wish to express my sincere appreciation to a number of people for their assistance in this investigation. I first thank my wife, Patricia, for her constant interest in the subject and assistance in the preparation of material. Dr. Murray S. Blum, advisor and close companion, is especially acknowledged for his continuous support and genuine interest in many problems which arose and for his many efforts in procuring specimens from many areas in the world. Special thanks also go to the following: Dr. William L. Brown, Cornell University, Ithaca, New York, and Dr. E. 0. Wilson, Harvard University, Cambridge, Massachusetts, for many ant species of particular interest and for information related to the taxonomic position of some species of ants; Dr. Howard Evans, Museum of Comparative Zoology, Harvard University, for several wasp species; Dr. D. H. Kistner, Chico State College, Chico, California, for Old World dorylines; Dr. C. W. Rettenmeyer, Kansas State University, Manhattan, Kansas, Lawrence, Kansas, for several New World dorylines; Dr. Daniel Janzen, University of Kansas, Lawrence, Kansas, for several species of pseudomyrmecine ants; Dr. L, D. Newsom, Department Head, Louisiana State University, for his interest and support during the investigation; Drs. J. H. Roberts, George H. Lowery, Walter Harman, L. D. Newsom and M. S. Blum, commit­ tee members, for their review and worthy criticism of the disserta­ tion. ii TABLE OF CONTENTS PAGE TITLE PAGE.............................................................i ACKNOWLEDGEMENTS. ..................................................... ii TABLE OF CONTENTS .................................................... iii LIST OF FIGURES ........................................................ v ABSTRACT................................................................ vi INTRODUCTION............................................................. I LITERATURE REVIEW ..................................................... 6 MATERIALS AND METHODS ................................................ 9 HOMOLOGIES AND TERMINOLOGY............................................ 14 RESULTS AND DISCUSSION................................................ 22 Evaluation of Material.............................................. 22 Soft Parts of the Poison Apparatus................................ 25 Poison S a c ............................................................25 Free Filaments....................................................... 26 Convoluted Gland..................................................... 33 Dufour's Gland....................................................... 34 Skeletal Components ................................................ 36 First Valvifers (Triangular Plates) ............................... 36 First Valvulae (Lancets)............................................40 Second Valvifers (Oblong Plates).................................. 46 Second Valvulae (Sting Bulb and Shaft)............................. 49 Third Valvulae (Gonostyli)......................................... 55 iii iv PAGE Fulcral Arms .58 Quadrate Plates (9th Hemitergites)..................................61 Spiracular Plates (8th Hemitergites).............................. 61 Anal Arc (10th Tergite) ............................................ 61 F u r c u l a .............................................................. 64 Autotomy of the Sting ............................................. 73 DISCUSSION.............................................................. 76 SUMMARY ................................................................ 83 LITERATURE CITED....................................................... 85 APPENDIX................................................................ 92 VITA ............................................................. 103 LIST OF FIGURES FIGURE PAGE 1. The evolutionary change from a connection between repro­ ductive system and ovipositor to a separation between the reproductive system and sting in the Hymenoptera. 5 2. Soft parts of the poison apparatus................ .24 3. Soft parts of the poison apparatus. ................. 28 4. Soft parts of the poison apparatus............................ 31 5. Gas ter s of an t s ................................................ 39 6. Sclerites of poison apparatus ................................. 42 7. Sclerites of poison apparatus ................................. 45 8. The furcula . ...................... .48 9. Sclerites of some Dorylinae ................................... 51 10. Sclerites of some Ponerinae and D o r y l i n a e ....................54 11. Sclerites of some Cerapachyinae ............................... 57 12. Diagrammatic illustration showing results of contrac­ tion of muscle 4 in most stinging Hymenoptera and in the dory linelike members of the Formicidae................ 60 13. Sclerites of some Pseudomyrmecinae. ................ 63 14. Sclerites of some Ponerinae, Pseudomyrmecinae, tfyrmicinae, and Formicinae.................... 66 15. Sclerites of poison apparatus ................................. 69 16. Diagrammatic illustrations of the evolution of the mutillid sting, the mechanism by which a wound is cut, and the function of soft parts in venom production......................... 7 2 ABSTRACT The results of a comparative study of the sclerites and asso­ ciated organs that compose the poison apparatus in hymenopterous insects are presented. Species of all 10 subfamilies of the Formi­ cidae and a few wasp species in three families are included in this investigation. Although there is generally a similarity in the basic structures of the poison apparatus of hymenopterous insects, there are individual characteristics which seem to be significant in determining phylogene­ tic relationships between the various groups. Certain characters are unique among individuals of a given group. The presence of external convolutions of the convoluted gland is a unique character among mem­ bers of the Formicinae. There is also a tendency in this subfamily to develop a bilobed Dufour's gland. In all of the aculeate Hymenoptera studied in this investigation, with the exception of the Dorylinae, Formicinae, Dolichoderinae, some Ponerinae and Cerapachinae, a sclerite known as the furcula is present. This small structure is probably the most important single sclerite in the hymenopterous poison apparatus when considering the sclerites as structures useful in the study of phylogeny. Its form varies considerably among the various groups and may correlate, to some extent, with the biology of a given species. Other characters that may be important in classification and phylogeny are the position of extension of the free filaments from the poison, sac, the shape and size of the free filaments, the reduction of various structures associated with the apparatus (e.g., sensory pegs vi vii and setae), and the reduction and elaboration of the sting sclerites themselves (especially within the Dolichoderinae and Formicinae), While all of these seem to be important phyletic characters, other characters may be of little, if any, significance in this respect. The presence or absence of lancet barbs seems to have little taxonomic significance, since their presence in one or more groups of aculeate hymenopterans is indeed unpredictable. Branching of the free fila­ ments seems to be present in all species of the Formicidae and thus cannot be used as a phyletic tool unless the extent of branching in any particular group could be of some importance. Following an explanation of the structures composing the poison apparatus and a comparative explanation of the soft parts and sclerites, a discussion of how this investigation correlates with the current trends of thought in formicid phylogeny is presented. Evidence resulting from this investigation indicates that the poison apparatus may indeed be a significant tool in the study of hymenopterous phylo­ geny. INTRODUCTION The sting of hymenopterous insects is a modified