The Caddisfly Family Phryganeidae (Trichoptera)

Patrick Colgan is the former executive director of the Canadian Museum
of Nature.

Within whole-organism biology, the foundational texts are those that
comprehensively describe the diversity of particular groups. Authored by
an emeritus curator of the Royal Ontario Museum, this book describes 74
species (three new to science) of one family of the largest and oldest
of case-making caddisflies, of which nearly 10,000 are known.

Of particular importance to the nonspecialist reader is the General
Section in which the biology of the group is broadly reviewed,
particularly case-making by the aquatic larvae and its relationship with
functional pupal mandibles. Highlights include important information on
the successive life stages of egg, larva, pupa, and adult; general
behavior; possible warning coloration of wings; fossil evidence and
links with moths and butterflies; and remarkable osmotically
semipermeable cocoons.

The family ranges from North America through Europe to Asia, and its
biogeography reflects the role of the continental split of the first two
regions. The high variation in some species in the genitalia of females
(but not males) raises interesting issues of reproductive isolation, on
which Wiggins focuses. In the Systematic Section, the features of each
species are described in detail. Researchers whose work involves
caddisflies will benefit greatly from the first-rate scholarship
underlying these descriptions.

The book includes an index, keys by each life stage for identifying
genera and species, and superb illustrations, including diagrams of
evolutionary relations and maps of geographic distribution. Overall,
this is a most impressive volume.

Despite its foundational importance, cataloguing the perhaps 30 million
species of natural diversity globally remains largely undone, and
systematics books as such appeal to only a specialized audience. The
present volume was itself originally intended as a ROM publication
before budgetary pressures stopped it: systematic volumes, like many of
the species they describe, are themselves regrettably endangered
entities. Highly recommended for specialists.