AMERICAN MUSEUM Novitates PUBLISHED BY THE AMERICAN MUSEUM OF NATURAL HISTORY CENTRAL PARK WEST AT 79TH STREET, NEW YORK, N.Y. 10024 Number 2786, pp. 1-33, figs. 1-33 June 7, 1984 Nesting Biology of Diphaglossine Bees (Hymenoptera, Colletidae) JEROME G. ROZEN, JR.' CONTENTS Abstract ...................................................................... 1 Introduction .................................................................. 2 Acknowledgments. 2 Techniques ................................................................. 2 Original Observations ....................................................... 3 Ptiloglossa arizonensis Timberlake .......................................... 3 Ptiloglossa fulvopilosa Cameron ............................................. 12 Ptiloglossa jonesi Timberlake ............................................... 16 Ptiloglossa guinnae Roberts ................................................ 18 Crawfordapis luctuosa Smith ............................................... 20 Policana albopilosa (Spinola) ............................................... 20 Discussion .................................................................... 23 Profile of the Biclogy of the Diphaglossinae ...................................... 30 Phylogenetic Considerations .................................................... 31 Literature Cited ............................................................... 31 ABSTRACT New data on the nesting biology ofthe following script accounts on these and other taxa throughout taxa of bees belonging to the Diphaglossinae are the entire geographic range of the subfamily. Spe- presented: Ptiloglossa arizonensis, fulvopilosa, cific subjects dealt with are habitat preference; nest jonesi, guinnae, Crawfordapis luctuosa, and Poli- site requirements; social organization; nest struc- cana albopilosa. This information is summarized ture, including cell orientation, shape, and size; and analyzed in relation to literature and manu- provisioning; oviposition; development; cocoon I Deputy Director for Research and Curator of Hymenoptera, American Museum of Natural History. Copyright American Museum of Natural History 1984 ISSN 0003-0082 / Price $3.00 2 AMERICAN MUSEUM NOVITATES NO. 2786 construction and fecal deposition; daily adult ac- phylogenetic relationships ofthe subfamily to oth- tivity; seasonal activity; and the relationship of er colletids are briefly discussed in light of nesting cleptoparasitic bees (Epeolini) to diphaglossines. biology, as well as the possible relationships be- A formal, synoptic overview ofthe biological fea- tween the Diphaglossinae and the Oxaeidae and tures of this subfamily is presented. Finally, the Stenotritidae. INTRODUCTION This paper summarizes and analyzes ex- study. I also extend my appreciation to Mr. isting information on the nest ecology and Vincent Roth, Resident Director of the architecture, nesting behavior, including co- Southwestern Research Station, for his per- coon construction, nest site associates, and sonal hospitality and cooperation during the other aspects of the biology of the Dipha- studies on Ptiloglossa arizonensis. Dr. Fred- glossinae, a tropical and semitropical group erick D. Bennett (West Indian Station, Com- of large-bodied, New World, ground-nesting monwealth Institute of Biological Control, bees. Curepe, Trinidad, West Indies) assisted me The initial impetus for the study was the in locating and excavating nests ofPtiloglossa discovery of the nests of Ptiloglossa arizo- fulvopilosa and lent specimens from his col- nensis in Portal, Arizona, in August 1982. lection so that their identification could be The site yielded data that then permitted an determined. Dr. Philip F. Torchio (ARS Bee interpretation of notes I had made on the Biology & Systematics Laboratory, Utah State nests of Ptiloglossa fulvopilosa years before University, Logan) kindly permitted me to on Trinidad. Dr. Mont A. Cazier, Curator read his manuscript (referred to elsewhere in Emeritus, American Museum ofNatural His- this study) on the nesting biology of Hylaeus tory, immediately offered his field notes, pho- bisinuatus. tographs, and specimens of Ptiloglossa Mr. Ian Stupakoffhelped in numerous ways jonesi, nests ofwhich he had excavated in the in the laboratory study at the American Mu- early 1960s in Portal. Dr. Radclyffe B. Rob- seum of Natural History and is responsible erts's informative paper (1971) on Ptiloglossa for the scanning electron microscope pho- guinnae as well as cocoons he lent me af- tographs of the bee cocoons and cells pre- forded an even broader understanding of the sented here. Mr. Stupakofis participation was biology of the genus. Dr. Gard W. Otis and supported by the Undergraduate/Graduate his associates as well as Dr. David W. Roubik Research Program, which is funded by the and Dr. Charles D. Michener kindly contrib- Greenwall Foundation. I thank Ms. Deborah uted their manuscripts and specimens of the Hickman, who painstakingly prepared the cocoons of Crawfordapis luctuosa so that manuscript for publication. comparisons of that species could be made The Southwestern Research Station pro- with Ptiloglossa. In the National Museum of vided laboratory space and living accom- Natural History, Smithsonian Institution, modations for the initial phase of the study Washington, I discovered the cells and co- of the biology of Ptiloglossa arizonensis. coons of Policana albopilosa excavated by The following specialists have kindly read Claude-Joseph in Chile in the early 1920s; I and contributed valuable advice on the borrowed them through the courtesy of Dr. manuscript: Dr. Radclyffe B. Roberts, De- Karl V. Krombein. Because of the coopera- partment of Entomology and Economic Zo- tion of so many people, it was possible to ology, Cook College, Rutgers, the State Uni- consider the nesting biology ofthe subfamily versity of New Jersey; Dr. Charles D. as a whole. Michener, Department of Entomology, the University of Kansas, Lawrence. ACKNOWLEDGMENTS TECHNIQUES I am grateful to the persons mentioned above for the loan of specimens, manu- Most ofthe procedures used in the present scripts, and other helpful contributions to the study are familiar to bee workers who exca- 1 984 ROZEN: DIPHAGLOSSINE BEES 3 vate ground-nesting species, and therefore I leaving the hard cast intact. Noncritical parts discuss here only two matters pertaining to of the cast, as for example the pouring area, technique. can be flattened with a file and collection data (1) Even though these bees are large and can be printed on the smooth surface. These their nest components correspondingly large casts are preserved in the collections of the and easy to observe, I consistently used a high American Museum ofNatural History as are quality stereoscopic microscope to examine samples ofadult bees, bee cells, and cocoons. cells, cell linings, food contents, cocoons, and behavior ofvarious immatures ofPtiloglossa ORIGINAL OBSERVATIONS arizonensis as soon as they were excavated. Considerable detailed information would Ptiloglossa arizonensis Timberlake have been lost without immediate exami- nation of material. LOCALITY: This species was first observed (2) Many features of the cells of bees are flying at approximately 5 A.M. Mountain taxon-specific. These include not only the di- Standard Time, on August 10, 1982, by Vin- mensions and proportions, composition and cent Roth outside a window of his house in thickness of cell linings, cell walls, and types Portal, Arizona. Attracted by their loud buzz- of closures, but also shape. Differences in ing at that early hour, he collected four fe- shape may be obvious (e.g., the shape of the males. After I noticed them later in the col- cell tops of Ptiloglossa compared with that lection ofthe Southwestern Research Station, of Policana) or subtle. When subtle, they are he directed me to the site on August 29. I difficult to analyze as cavities. In recognition found several nests during the daytime, began of this problem Stupakoff investigated ways observations on August 31, and continued of casting cells so that their shape as a solid them through September 6, 1982. Nine nests could be more accurately studied, measured, were discovered where Roth had first seen and preserved for future comparisons. After the adults, and a larger concentration ofmore consultation with the Department of Verte- than 50 nests was centered approximately 2 brate Paleontology of the American Mu- m. away on the property of James F. Rich- seum, he tested the use of latex and Smooth- ards.2 on®, substances that have been employed for DESCRIPTION OF SITE: Both nest groups oc- casting fossils, but found that they took too cupied a terrace about 2 m. above Cave Creek, long to dry and could not be used in the field an intermittent stream, and were subjected where the soil was wet. These substances also to flooding under only the most extreme storm deteriorate after about five years of storage. conditions. An open riparian forest canopy Several brands of plaster were also tested: consisting primarily of sycamore and juniper Gladstone®' was very hard, but usually pro- permitted sunlight to reach the site during duced tiny air bubbles. Although somewhat much of the day, and the sky overhead was softer, Speedrock 3 proved to be the most sat- visible from all burrow entrances except for isfactory in that it showed few air bubbles a few at the edge of a large rock. Both aggre- and took approximately an hour to harden. gations (fig. 17) were in nearly horizontal Diagrams of