Book excerpt: Everyone in Louisiana knows something about crawfish -- especially how tasty they can be when boiled with just the right combination of spices. Yet these small crustaceans -- known as "crayfishes" by scientists and "mudbugs" by many fishermen -- offer more than a delicious meal. In Crawfishes of Louisiana, Jerry G. Walls identifies the state's thirty-nine types of crawfishes, explains their biology, and explores their importance in Louisiana's history, culture, and economy. Walls briefly describes each species and subspecies of crawfish currently known to live in Louisiana, as well as their natural history and complicated breeding biology. Detailed illustrations depict pertinent taxonomic features, color photographs of living specimens aid in identification, and maps indicate species distribution throughout the state. Two identification keys further assist users in classifying any crawfish they encounter. Drawing on his experiences collecting crawfishes over the past fifty years, Walls explores changes in their populations and in the environmental health of their habitats. In the early part of the twentieth century, many Louisianans thought eating crawfish outside of Lent was an embarrassing admission of poverty. Now crawfish is a celebrated delicacy in restaurants and at festivals offering crawfish boils, crawfish races, crawfish cook-offs -- even the election of a crawfish queen and court. Crawfish provide recreational fishing opportunities in ditches and lakes across southern and central Louisiana, and commercial fishermen net roughly 70,000 tons of crawfish each year and process them in a fishery employing over 2,500 people. Walls offers insights into all of these areas along with cooking tips and recipes and, at the other extreme, instructions for keeping crawfish as pets. Crawfishes of Louisiana is an invaluable and enjoyable resource for all fans of this famous Louisiana crustacean.