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Damselflies of Alberta:
Flying Neon Toothpicks in the
Grass
John Acorn
University of Alberta Press, Edmonton
2004, 156 pages
Price: $22.50 (Paper)
ISBN: 0-88864-419-1
Entomologists who know John Acorn’s earlier work, Tiger Beetles of
Alberta, need only to be told that this work is similar in format
and quality to that book. Those who have not had this good fortune
should know that both books combine a light, conversational style with
sound science and excellent photography. The book is accessible to
beginners and is aimed at the amateur naturalist, although it is equally
useful to the professional entomologist. Acorn has made a special effort
to avoid technical terms where possible. For instance, he finds it
convenient to refer to the two pairs of appendages at the end of the
male abdomen as the “upper and lower claspers” without entering into the
controversies about their homologies. However, he always gives the
equivalent terms used in other works to which the reader might refer.
Alberta
has 22 species of damselflies, 14 of which are also found in northern
New England. The other eight are western or far northern species. This
means that the book and especially the pictures are useful in the
northeastern United States, although some additional species are not
covered here.
Six introductory chapters cover several pertinent topics.
The first chapter focuses on the relationships of damselflies to other
insects, their larval stages, and features of the adult useful in field
identification. In subsequent chapters, Acorn discusses what can be
learned of damselfly biology by observing them in the field, and he
includes a chapter (5) on collecting, field identification, and rearing
larvae. Using the history of damselfly study in Alberta, Acorn discusses
the historical interactions of amateur and professional entomologists.
Finally, in separate chapters, he describes the habitat preferences for
different wetlands and habitats, and includes an excellent chapter on
damselfly conservation. This final chapter has themes that could easily
be applied to insect conservation in a broader sense.
Each species has a set of informative details and is
equipped with a high-quality photograph of males and females.
Distinguishing characteristics, particularly color markings observable
in the field, are given for each species. Sexual dimorphisms, color
patterns, and color changes with age also are presented. The ecology of
each species is discussed in some detail, including habitats, life
histories, ranges, and suggestions of places where each species can be
found. One unique feature of this guide is that Acorn has included notes
on a variety of topics for each species. These notes present historical
and contemporary accounts from other collectors, Acorn’s anecdotes,
discussions of the distribution and range changes and speculation as to
their causes, and specific behaviors. Finally, distribution maps for
each species show ranges in Alberta and in North America.
Appendices
include a checklist and key of Alberta damselflies. Also, a list of
useful sources to professional and amateur damselfly aficionados
includes supply houses, entomology societies, and museums. Finally, a
glossary, bibliography, and gallery of damselflies (a diagrammatic
comparison of color patterns) are included.
I highly
recommend this book and find little to criticize. In addition to the
information content, the witty style of the author makes it a good read.
An index would have been helpful, and I would have liked a bit more
information on larval stages, but these are very minor criticisms.
Finally, I look forward to seeing the later books in the series, of
which the next planned will focus on “lady bugs” (Coccinelidae).
Ross
T. Bell
Biology Department
University of Vermont
Marsh Life Science Bldg.
Burlington, VT 05405-0086
E-mail: Ross.Bell@uvm.edu
American Entomologist
Vol. 52, No.4, Winter 2006
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