1970] 
Eichwort — Mason Bee 
199 
is extending its range (L. Pechuman, personal communication). In 
addition, 4 other North American megachilid bees, Osmia coerulescens 
(Linnaeus), O. inermis (Zetterstedt) , O. nigriventris (Zetterstedt) , 
and Megachile centuncularis (Linnaeus)', also occur in the Old 
World (Mitchell, 1962), and may have been accidentally introduced 
by man before records were kept. 
All of the introduced megachilids except the mason bee are poly- 
lectic, although they show preferences for certain flowers and fre- 
quently visit plants of European origin (Hurd, 1954; Stephen and 
Torchio, 1961; Pechuman, 1967). Hoplitis anthocopoides is the 
first oligolectic bee of any family to accidentally follow its host 
plant to the United States. The host is a widespread and common 
weed and the nest sites are abundant and rarely used by native bees. 
There is little doubt that H. anthocopoides will extend its range 
over much of eastern North America. Since even vanguard mason 
bees can be easily detected on roadside stands of viper’s bugloss, its 
range extension can be followed more exactly than that of any other 
introduced species. I urge entomologists in the Northeast to be on 
the watch for the mason bee. 
Summary 
Hoplitis ( Hoplitis ) anthocopoides occupied a 25 mile diameter 
range in the Helderberg Plateau of Albany County, New York, in 
1969. It is the first species of the nominate subgenus to occur in 
the Western Hemisphere. The bee is described and distinguished 
from other American Hoplitis , and Hurd and Michener’s key to 
the American subgenera and Mitchell’s key to the Eastern species 
of Hoplitis are modified to include H. anthocopoides. The mason 
bee builds exposed mortar-and-pebble nests on surfaces of rocks and 
visits only the introduced weed Echium vulgare for pollen and 
nectar. 
Acknowledgments 
I am grateful to the Edmund Niles Huyck Preserve of Rens- 
selaerville, New York, which awarded a summer research fellowship 
to my wife and myself and provided the facilities which made this 
study possible. I thank Dr. Eduard Stanek of Uhersky Brod, 
Czechoslovakia, for providing an unpublished description of H. 
anthocopoides and many helpful comments, and for comparing New 
York specimens with European ones. The Cornell University insect 
collection provided European specimens of “Osmia caementarm' 
that first enabled me to identify the bee. I thank Dr. LaVerne L. 
