disentangling the phenotypic variation and pollination biology of the cyclocephala sexpunctata

180 Pages·2011·5.83 MB·English

by  Matthew Robert Moore

DISENTANGLING THE PHENOTYPIC VARIATION AND POLLINATION BIOLOGY OF
THE CYCLOCEPHALA SEXPUNCTATA SPECIES COMPLEX (COLEOPTERA:
SCARABAEIDAE: DYNASTINAE)

A Thesis by

Matthew Robert Moore

Bachelor of Science, University of Nebraska-Lincoln, 2009

Submitted to the Department of Biological Sciences
and the faculty of the Graduate School of
Wichita State University
in partial fulfillment of
the requirements for the degree of
Master of Science

July 2011
© Copyright 2011 by Matthew Robert Moore

All Rights Reserved
DISENTANGLING THE PHENOTYPIC VARIATION AND POLLINATION BIOLOGY OF
THE CYCLOCEPHALA SEXPUNCTATA SPECIES COMPLEX (COLEOPTERA:
SCARABAEIDAE: DYNASTINAE)

The following faculty members have examined the final copy of this thesis for form and content, and
recommend that it be accepted in partial fulfillment of the requirement for the degree of Master of
Science with a major in Biological Sciences.

________________________
Mary Jameson, Committee Chair

________________________
Bin Shuai, Committee Member

________________________
Gregory Houseman, Committee Member

________________________
Peer Moore-Jansen, Committee Member

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DEDICATION

To my parents and my dearest friends

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"The most beautiful thing we can experience is the mysterious. It is the source of all true art and all
science. He to whom this emotion is a stranger, who can no longer pause to wonder and stand rapt in awe,
is as good as dead: his eyes are closed." – Albert Einstein

v
ACKNOWLEDMENTS

I would like to thank my academic advisor, Mary Jameson, whose years of guidance, patience
and enthusiasm have so positively influenced my development as a scientist and person. I would like to
thank Brett Ratcliffe and Matt Paulsen of the University of Nebraska State Museum for their generous
help with this project. Several others deserve credit for helping me along the way: Dr. Maxi Polihronakis,
Dr. Bin Shuai and Dr. Karen Brown-Sullivan. Lastly, I am very grateful to the researchers at the Biofinity
Project (http://biofinity.unl.edu) for their funding of this work.

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ABSTRACT

Researching cryptic biodiversity is an integrative process that uses a “total evidence” approach to
identify population-level evolutionary lineages (species). Cryptic species of aroids have been discovered
but the existence of cryptic pollinator species has not been addressed. The highly polymorphic scarab
beetle, Cyclocephala sexpunctata, is a hypothesized pollinator of two cryptic aroid species. This research
integrates detailed morphological data, spatial and distribution data, mitochondrial CO1 sequence data
and host plant associations to test the hypothesis that cryptic species of Cyclocephala are visiting aroid
flowers. Nine morphologically similar Cyclocephala species were included to address identification
problems among similar species. A new country record was found for C. pan (Honduras). A female
paratype specimen of C. letiranti was determined to be a female C. sexpunctata raising the possibility that
there are no female type specimens of C. letiranti. Four unique male paramere forms (morphotypes) were
found in C. sexpunctata and the allied species C. brevis. These paramere forms were associated with four
female morphotypes that have a diagnostic form of the ventral surface of the epipleural pillow. The
ventral form of the female epipleural pillow is described here for the first time and is a new character for
the genus Cyclocephala. Detailed elevational and distribution data indicate that the morphotypes of C.
sexpunctata and C. brevis are rarely collected together at specific localities. A checklist of cyclocephaline
floral associations was compiled. Examination of voucher specimens and published floral associations
indicate that the morphotypes described here visit different species of flowers within their hypothesized
elevational range. Mitochondrial CO1 data demonstrate that C. sexpunctata is polyphyletic but the
monophyly of C. brevis could not be addressed. The combination of these datasets indicates that the
morphotypes described here are cryptic species though their taxonomy remains unresolved due to large
numbers of synonyms.

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TABLE OF CONTENTS

Chapter Page

1. INTRODUCTION 1
1.1 Introduction 1
1.2 Questions and Significance 2

2. BACKGROUND 4
2.1 The genus Cyclocephala 4
2.2 Variation in Species-level Diagnostic Characters 5
2.3 Variation and Diagnosability of C. sexpunctata, C. brevis and
Morphologically Allied Species 5

3. MATERIALS AND METHODS 8
3.1 Taxa Selection 8
3.2 Morphological and Distribution Data 8
3.3 Scoring Maculae Phenotypes 10
3.4 Molecular Methods 11
3.4.1 DNA Extraction 11
3.4.2 Mitochondrial CO1 Amplification 11
3.4.3 Purification, Sequencing and Contig Assembly 12
3.4.4 Alignment and Parsimony Analysis 13
3.5 Checklist of Floral Associations for the Cyclocephalini 13

4. RESULTS AND DISCUSSION 16
4.1 Taxa Selection and Specimen Acquisition 16
4.1.1 Taxa Selection 16
4.1.2 Specimen Acquisition 17
4.1.3 Discussion 18
4.2 The Morphology and Distribution of Morphotypes 21
4.2.1 Morphotype 1 22
4.2.2 Morphotype 2 29
4.2.3 Morphotype 3 36
4.2.4 Morphotype 4 45
4.2.5 Sympatry of the Morphotypes 51
4.2.6 Discussion 51
4.3 Maculae Phenotypes 54
4.3.1 Morphotype 1 55
4.3.2 Morphotype 2 57
4.3.3 Morphotype 3 60
4.3.4 Morphotype 4 63
4.3.5 Discussion 65
4.4 Molecular Relationships 66
4.4.1 Discussion 68
4.5 Checklist of Floral Associations for the Cyclocephalini 70
4.5.1 Discussion 80

5. CONCLUSIONS 83

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TABLE OF CONTENTS (continued)

Chapter Page

REFERENCES 87

APPENDICES 101
1. Molecular Voucher Specimen and Sequence Data 102
2. Mitochondrial CO1 Alignment 113
3. Checklist of Floral Associations for the Cyclocephalini 121

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LIST OF TABLES

Table Page

1. Taxonomic history of C. sexpunctata. 7

2. Taxonomic history of C. brevis. 7

3. Primers for CO1 amplification. 12

4. CO1 sequences from NCBI. 13

5. Cyclocephala species of the C. sexpunctata species group examined during this study. 16

6. Private and institutional collections providing loaned material. 17

7. Elevational distribution of morphotype 1. 27

8. Elevational distribution of morphotype 2. 34

9. Elevational distribution of morphotype 3. 43

10. Elevational distribution of morphotype 4. 50

11. Localities of sympatry between morphotypes. 51

12. Cyclocephaline synonyms reported in floral association literature. 71

13. Unresolved cyclocephaline names reported in floral association literature. 71

14. Plant synonyms reported in floral association literature. 71

15. Manuscript names and unresolved plant names reported in floral association literature. 73

16. Generic level summary of cyclocephaline floral associations based on most specific data. 73

17. Host plant data for the C. sexpunctata species complex. 78

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