Megaspores from the Upper Cretaceous (Campanian) Horseshoe Canyon Formation of south-central Alberta, Canada, with a review of the genera Costatheca and Spermatites

Abstract

Eighty-nine samples from three boreholes penetrating the Horseshoe Canyon Formation (Late Campanian) in south-central Alberta (Canada) were investigated for megaspore content. The samples were found to contain 49 species belonging to the genera Azolla, Bacutriletes, Costatheca, Dictyothylakos, Echitriletes, Erlansonisporites, Ghoshispora, Glomerisporites, Minerisporites, Molaspora, Monophyllosporites, Paxillitriletes, Spermatites, Striatriletes and Trileites, including one new species of Spermatites (S. reticulatus). Deposits representing low-lying coastal plains with widespread peat swamps, meandering channels and back swamp environments yielded the highest numbers of megaspores. An analysis of characteristics of the 22 species of Costatheca and 18 species and one subspecies of Spermatites leads to the proposal of a system of shape classes. Dichotomous keys to species were prepared. The geographical and stratigraphical distributions of the genera were also reviewed to elucidate their potential use in biostratigraphic and palaeoecological studies.

Keywords:

• megaspores
• Costatheca
• Spermatites
• Horseshoe Canyon Formation
• Campanian
• south-central Alberta
• Canada

Acknowledgements

The authors would like to express their appreciation to Dr. D.R. Braman (Royal Tyrrell Museum of Palaeontology, Drumheller) for his help in the improvement of the manuscript. He provided constructive comments and discussions on stratigraphy, age assignment and palaeoenvironmental issues. The research is updated from the first author's thesis study (Kutluk 1985) at the University of Calgary. H. Kutluk is indebted to Dr. A.R. Sweet (Geological Survey of Canada) for his guidance and valuable suggestions during the preparation of the thesis. The authors are indebted to Mrs. P. Baillie, Mr. R. Larush and Mrs. D. Johnston for their skillful assistance in the laboratory, photography and SEM work. Funds for the project came from Natural Sciences and Engineering Research Council of Canada (NSERC) Grant to Dr. L.V. Hills and by University of Calgary scholarships (graduate teaching and research assistanships) to H. Kutluk. The anonymous reviewers are thanked for their useful remarks, suggestions and advice for the improvement of the manuscript.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Notes on contributors

Hatice Kutluk

Dr LEONARD V. HILLS (3 January 1933 to 4 August 2013) was an accomplished scholar, having received a BSc with honours in geology in 1960, an MSc in geology from the University of British Columbia in 1962 and a PhD in palynology from the University of Alberta in 1965. He was Emeritus Professor and one of the ‘founding fathers’ of the Department of Geoscience, University of Calgary. While Len's primary field of research was palynology, his published research also included papers in archaeology, botany and zoology. His contribution to graduate education at the University of Calgary is remarkable; he supervised nearly 100 MSc and PhD theses and participated in well over 330 graduate committees as examiner. In 1995, Len was awarded the Graduate Students Association Teaching Excellence Award in recognition of those efforts. With Jan Jansonius, Len Hills published the Genera card file of fossil spores and pollen, a massive reference volume contributing to the taxonomy and nomenclature of palynomorphs. For many years he served actively with the Arctic Institute of North America, where he was a Fellow. He was honored with the Canadian Society of Petroleum Geologists’ President's Award in 1980 and became an Honorary Member in 1996 for his outstanding service to the Society. He was an Adjunct Research Scientist to the Royal Tyrrell Museum of Palaeontology. In 2010, a session of the GeoCanada National Convention held in Calgary was dedicated to Len by his students and collaborators. He will be dearly missed by all who knew him. (Compiled from the University of Calgary)

Leonard V. Hills

HATICE KUTLUK graduated from the Middle East Technical University, Ankara, with a BSc degree in geology. She received her MSc from the University of Calgary, Alberta (1985) and her PhD from the Institute of Marine Sciences, İstanbul University (1994) in the field of palynology. Hatice works in the Geology Department, Eskisehir Osmangazi University, and has taught various courses in geology, palaeontology and micropalaeontology. Her reseach works are mainly on the systematics, biostratigraphy and palaeoecology of Mesozoic and Cenozoic palynomorphs, and the phytogeographical distribution of extant plants in Turkey. Recent research interests also involve non-pollen palynomorphs of Holocene sediments. Hatice has also worked as a palynologist with the Turkish Petroleum Company in Ankara on a variety of projects.