MISCELLANEOUS PUBLICATIONS MUSEUM OF ZOOLOGY, UNIVERSITY OF MICHIGAN, NO. 153 A Revisionary Study of the Genus Acanthagrion (Odonata: Zygoptera) BY Justin W. Leonard Ann Arbor MUSEUM OF ZOOLOGY, UNIVERSITY OF MICHIGAN October 7, 1977 MISCELLANEOUS PUBLICATIONS MUSEUM OF ZOOLOGY, UNIVERSITY OF MICHIGAN, NO. 153 A Revisionary Study of' the Genus Acanthagrion (Odonata: Zygoptera) BY Justin W. Leonard Ann Arbor MUSEUM OF ZOOLOGY, UNIVERSITY OF MICHIGAN October 7, 1977 CONTENTS Page FOREWORD ............................................. vii INTRODUCTION ......................................... 1 ACKNOWLEDGEMENTS .................................... 2 SOURCES AND DISPOSITION OF MATERIAL STUDIED .............. 3 DISPOSITION OF TYPES .................................... 4 CHARACTERIZATION OF TIIE GENUS ACANTHAGRION ............ 4 DESCRIPTION OF STRUCTURE ............................... 5 Coloration ............................................ 6 Development and Variation of Coloration ........................ 7 EVALUATION OF CHARACTERS .............................. 9 The Penis ............................................. 10 The Male Abdominal Appendages ............................. 11 The Mcsepisternal Fossae ................................... 11 Other Structural Characters ................................. 11 DISTRIBUTION .......................................... 12 RECOGNITION AND DISPOSITION OF SPECIES AND INTRAGENERIC GROUPS ............................. 14 ABSENCE OF INTERGRADATION ............................. 15 SYSTEMATICSECTION ..................................... 17 Key to the Species of Acanthagrion ............................ 18 Males .............................................. 18 Females ............................................ 22 Rubrifrons Group ........................................ 25 A . rubrifrons ......................................... 25 A . longispinosum ...................................... 29 AbunacGroup .......................................... 32 A . jessei n . sp ......................................... 32 A . temporale Sclys ..................................... 35 A . abunae n . sp ........................................ 37 A . inexpectzinz n . sp ..................................... 41 A . amazonicum Sjostedt ................................. 44 Abluium Group ......................................... 47 A . ahlutum Calvert ..................................... 48 A . hermosae n . sp ...................................... 51 Apicale Group .......................................... 52 A . phallicornis n . sp ..................................... 53 A . obsoletum (Forster) .................................. 56 A . apicale Selys ....................................... 61 Yungarum Group ........................................ 66 A . yungarzlm Ris ...................................... 73 Ascendens Group ........................................ 77 A . lzcnnerlii Williamson ................................... 78 A . quadratum Sclys ..................................... 81 A . trilobatum n . sp ...................................... 85 A . asce?zdeizs Calvert .................................... 90 Viridescens Group ....................................... 94 A . truncatum Selys ..................................... 95 A . viridescens n . sp ..................................... 98 A . lancea Sclys ........................................ 102 A . pzcile (Rambur) .................................... 106 A . deceptum n . sp ......................................110 A . perz~vianumn . sp .....................................114 Adustum Group ......................................... 119 A . ininutum n . sp ...................................... 119 A . adustz~mWilliamson .................................. 122 A . indefenszim Williamson ................................ 125 Chararum Group ........................................ 128 A . latapisty lunz Calvert .................................. 129 A . chararum Calvert .................................... 130 A . chacoi;izse Calvert .................................... 132 GENERAL SUMMARY ......................................133 CONCI. USIONS ........................................... 136 LIST OF LOCALITIES MENTIONED ............................ 139 LITERATURECITED ......................................145 APPENDIX. by L . K . Gloyd ...................................146 INDEXTOTAXA ......................................... 153 PLATESI-XIX ........................................... 155 ILLUSTRATIONS Plate Page I. Penes of Acanthagrion rubrifrons, A. longispinosum, A. jessei, A. temporale, A. abunae and A. inexpecturn ............................ 11. Penes of A. arnazonicurn, A. abluturn, A. hermosae, A. phallicornis, A. obso- letum and A. apicak .................................. 111. Penes of A. yungarum, A. risi, A. williamsoni, A. kennedii, A. quadratum and A. trilobatum ...................................... IV. Penes of A. ascendens, A. truncatum, A. uiridescens, A. lancea, A. gracile and A. deceptum ...................................... V. Penes of A. peruuianum, A. rninutum, A. adustum, A. indefensuna, Aeol~~qion sp. and Cyanallagma intcrruptum .......................... VI. Male appendages of A. rubrifrons, A. longispinosum, A. jessei and A. tem- porale .......................................... VII. Male appendages of A. abunae, A. inexpectum, A. amaronicum and A. ab- lutum ........................................... VIII. Male appendages of A. hermosae, A. phallicornis, A. obsoletum and A. api- calc ............................................ IX. Male appendages of A. yungurum, A. risi, A. williamsoni and A. ken- nedii ........................................... X. Male appendages of A. quadratum, A. trilobatum, A. ascendens and A. truncatum ........................................ XI. Male appendages of A. viridescens, A. lancea, A. gracile and A. decep- tum ............................................ XII. Male appendages of A. peruuianum, A. minuturn, A. adustum and A. in- defensum ........................................ XIII. Mesepisternal fossae of A. rubrifrons, A. longispinosum, A. jessei, A. tem- porule, A. abunae and A. amazonicum ....................... XIV. Mesepisternal fossae of A. phallicornis, A. obsoletum, A. apicale, A. ublutum, A. hennedii and A. qnadratum ............................ XV. Mesepisternal fossae of A. trilobatum, A. ascendens, A. truncatum, A. uirides- ccns, A. lancea and A. gracile ............................ XVI. Mcsepistcmal fossae of A. peruuianum, A. deceptzam, A. yungarum, A. risi and A.aduslum ....................................... XVII. Locality rccords for the Rubrifrons, Yungarum and Abunae Groups of Acan- thagrion ......................................... XVIII. Locality rccords for thc Apicale, Ascendens and Chararum Groups of Acan- thngrion ......................................... XIX. Locality records for the Viridcscens and Ablutum Groups of Acnntha,Tion . FOREWORD Of unusual occurrence is the publication oI a thesis 40 ye,Lrs after its completion and acceptance in partial tultilln~cntof the require- ments for the Doctor of Philosophy degree, ant1 also nIter the death of the author. Such thesis is herewith published in the Miscellnneous Publications of the Museum of Zoology, as a memorial number for Dr. Justin W. Leonard. The greater part of the study reported here was carried on during the period 1931-34 while Dr. Leonard was a graduate student at the University of Michigan. Since that time, the varied demands of his professional duties, and the difIiculties in obtaining funds for the printing, resulted in repeated delays or publication. A few years ago, Dr. B. E. Montgomery and Dr. Leonard began to revise the original mCmuscript and made a few minor changes in the Introduction and preliminary discussion concerning the genus Acantha,qrzon. These have been incorporated in this published version. The hopeful waiting ior the publication of this work has apparently been responsible for the delay in describing new species by other authors. Since the completion of the thesis, only six new species and two new subspecies have been described. These arc listed herewith in an Appendix. Lconord I<. Gloyd INTRODUCTION The genus ;lca~zthagrio~zwas erected for the reception of certain Neotropical coenagrionine Zygoptera by the great Belgian odonatol- ogist, Baron Edmond de Selys-Longchamps, in 1876. Into this genus, at the time of its description, he placed Agrion ~racilr,described "l'rom Brazil" by Rambur (1842) as the first species of "2e groupe: (A. GRACILE)." At thc samc time, Selys published descrip- tions of 13 new forms - 8 as species (apicale, chcl$erum, i~ztcr- ruptum, laleralc, nigrinuchale, temporale, trimaculalum and trun- catz~f~z),2 as varieties of cq:.mcile (czi~zcatumand qunclratzi17z), anti 3 as races of gracile (la~zcea,rninarzi?n and uitlua). No further additions were made to the gcnus for 23 years, when Calvert (1 899) tlescribed lala/~istyl~.im.Ten years later, Calvert (1909) described 9 more forms - 4 as species (clzacoense, clznmrum, clzirilzzianurn and cuyabae) ant1 5 as subspccics (ablz~tumand useendens as subspecies of gracile, fi~nense and ,frcirensc as subspccics of cziyabae, and rusticurn as a doubtfully distinct subspecies of clzeliferzinz). Ris described G forms for the genus - 5 as species (amOiiqzizim in 1904, aczitunz, luna and yulzsarzim in 1916, li~zd~zrriin 1928) and one, honarie~zsc,as a sub- species of ilzterru[)tzi17z in 1913. E. B. Williamson (1916)