Some Aspects of the Ecology of Millipedes (Diplopoda) Thesis
Total Page:16
File Type:pdf, Size:1020Kb
Some Aspects of the Ecology of Millipedes (Diplopoda) Thesis Presented in Partial Fulfillment of the Requirements for the Degree Master of Science in the Graduate School of The Ohio State University By Monica A. Farfan, B.S. Graduate Program in Evolution, Ecology, and Organismal Biology The Ohio State University 2010 Thesis Committee: Hans Klompen, Advisor John W. Wenzel Andrew Michel Copyright by Monica A. Farfan 2010 Abstract The focus of this thesis is the ecology of invasive millipedes (Diplopoda) in the family Julidae. This particular group of millipedes are thought to be introduced into North America from Europe and are now widely found in many urban, anthropogenic habitats in the U.S. Why are these animals such effective colonizers and why do they seem to be mostly present in anthropogenic habitats? In a review of the literature addressing the role of millipedes in nutrient cycling, the interactions of millipedes and communities of fungi and bacteria are discussed. The presence of millipedes stimulates fungal growth while fungal hyphae and bacteria positively effect feeding intensity and nutrient assimilation efficiency in millipedes. Millipedes may also utilize enzymes from these organisms. In a continuation of the study of the ecology of the family Julidae, a comparative study was completed on mites associated with millipedes in the family Julidae in eastern North America and the United Kingdom. The goals of this study were: 1. To establish what mites are present on these millipedes in North America 2. To see if this fauna is the same as in Europe 3. To examine host association patterns looking specifically for host or habitat specificity. In 2008-2009 millipedes and mites were collected in the eastern U.S. and in the ii U.K. Millipedes were identified to species and mites were identified to morphospecies. Prevalence of mites for most species is low to medium (< 1/3) and average intensity is low, < 5 mites. Little evidence was found for host specificity in family Julidae, although this may be a possibility in some other taxa. There was some evidence for locality specificity on the part of the mites, and specificity for area or habitat cannot be rejected. Overall this study shows that millipedes seem to have the same mites as other ground dwelling arthropods. iii Dedication Dedicated to my husband, Lee T. Ayres, and my grandmother, Edith Catherine Myers Saulsbury. iv Acknowledgements Dr. Hans Klompen for advice, moral and financial support and review of a lot of drafts of this thesis. Dr. Andrew Michel for assistance in data collection and analysis and review of this thesis. Dr. John W. Wenzel for sound political advice and review of this thesis. Dr. Petra Sierwald and the Department of Insects at the Field Museum of Natural History, Chicago, IL for partial funding of this research. Dr. Henrik Enghoff for collection of samples. Dr. Helen J. Read for collection of samples. Lee T. Ayres for field support, data analysis, review of later drafts of this thesis and personal support to allow for the completion of this research. v Vita June 1991 …............................................................... Holy Name Catholic School 1999 …....................................................................... B.F.A with Distinction in Art, The Ohio State University 2002 …....................................................................... M.F.A. Studio Art, The School of the Art Institute of Chicago 2004-2005 ….............................................................. Faculty, The School of the Art Institute of Chicago, Chicago, IL 2002-2004 ….............................................................. Faculty, Robert Morris College, Chicago, IL 2008 …........................................................................ B.S. with Research Distinction in Entomology, The Ohio State University 2009-2010 ….............................................................. Graduate Teaching Assistant, The Ohio State University Publications Schmidt-Rhaesa, A., M. A. Farfan, and E. C. Bernard. First Record of Millipedes as Hosts for Horsehair Worms (Nematomorpha) in North America. Northeastern Naturalist. 2009: 16(1):125-130. Shear, William A., Julian J. Lewis, and Monica Farfan. Diplopoda, Chordeumatida, vi Cleidogonidae, Pseudotremia salisae Lewis: Distribution extension north of the Ohio River in Ohio and Illinois, U. S. A. Check List 2007: 3(1). Fields of Study Major Field: Evolution, Ecology, and Organismal Biology vii Table of Contents Abstract ….......................................................................................................................... ii Dedication …..................................................................................................................... iv Acknowledgements …........................................................................................................ v Vita …................................................................................................................................ vi List of Tables …................................................................................................................. xi List of Figures ….............................................................................................................. xii Chapter 1: Millipedes As Ecological Engineers in the Process of Nutrient Cycling …..... 1 1.1. INTRODUCTION …...................................................................................... 1 1.2. THE PRIMARY STEPS IN LITTER BREAKDOWN …............................... 3 1.2.1. Mineralization ….................................................................................... 4 1.3. THE ROLE OF MILLIPEDES IN LITTER BREAKDOWN ….................... 6 1.3.1. Mechanical processing …........................................................................ 6 1.3.2 Factors affecting ingestion and fecal production rates …......................... 7 1.3.3 Chemical decomposition and assimilation by millipedes ….................. 13 1.3.4. Millipedes as nutrient stores …............................................................. 17 1.4. THE EFFECT OF MILLIPEDE ACTIVITY ON FUNGI AND BACTERIA …........................................................................................................................... 20 1.4.1. Chemical and Structural Characteristics of Fecal Pellets …................. 20 viii 1.4.2. Effects of millipede activity on microbial and fungal populations ..… 25 1.5. EFFECTS OF FUNGI AND BACTERIA ON MILLIPEDES ….............… 28 1.5.1 Consumption of microbes and fungi ….................................................. 29 1.5.2 Coprophagy …........................................................................................ 32 1.6. APPLICATIONS OF MILLIPEDE ECOLOGY RESEARCH …................. 33 1.7. DISPERSAL AND COLONIZATION BY MILLIPEDES …....................... 36 Chapter 2: Atlantic Millipedes and their Mite Associates…............................................ 39 2.1 INTRODUCTION …..................................................................................... 39 2.1.1 Goals of Study ….................................................................................... 49 2.1.2 Hypotheses …......................................................................................... 49 2.2. METHODS AND MATERIALS ….............................................................. 50 2.2.1 Collection Localities ….......................................................................... 50 2.2.2 Collection Methods …............................................................................ 52 2.2.3 Determinations …................................................................................... 52 2.2.4 Prevalence and Average Intensity …...................................................... 53 2.3. RESULTS ….................................................................................................. 55 2.3.1 Astigmata …........................................................................................... 55 2.3.2 Rhizoglyphus …...................................................................................... 57 2.3.3 Sancassania …........................................................................................ 57 2.3.4 Schwiebea …........................................................................................... 57 2.3.5 Mesostigmata …..................................................................................... 67 2.3.6 Mite-Millipede Associations ….............................................................. 67 ix 2.3.7 Julid Millipede Collections …................................................................ 67 2.3.8 Non-Julid Millipede Collections …........................................................ 72 2.3.9 Mite Taxa and Relation to Locality ….................................................... 73 2.4. CONCLUSIONS …....................................................................................... 74 2.4.1 Caveats …............................................................................................... 79 2.4.2 Additional findings: Non-julid millipede hosts ….................................. 80 2.5 SUMMARY …...........................................................................................… 82 References ….................................................................................................................... 84 Appendix A: Accession Codes for Millipede Vouchers …..............................................