Strictly speaking, entomology is the study of insects, their form and behaviour. Here we'll blur the edges and include articles on vertebrates, molluscs, crustaceans, and anything else that features significantly in fishes' diets, and can feasibly be represented with an artificial fly. The focus is on details of particular significance to the angler.

If you feel inspired to look more deeply into this aspect of fly fishing, then you may want to refer to the further reading section accompanying some accounts, or perhaps take a look at the resources section in the sidebar; this contains links to some zoological and entomological establishments and their archives.




Classification Order: Megaloptera; Family: Sialidae; Subfamily: Sialinae; Genus: Sialis. Lifecycle All alderflies have a lifecycle that includes a complete metamorphosis with only the larval stage being aquatic. Commonly, in late spring and early summer (May/June for species Sialis lutaria and S. fuliginosa, S. mohri and S. vegans) adults can … Continue reading




The presence of stoneflies in a river or stream has always been a good indicator of a healthy aquatic environment. These members of the insect order Plecoptera are found in cool, well oxygenated flowing waters and occasionally along the wave-swept … Continue reading


Freshwater Shrimp


The presence of shrimp or scuds in a lake or stream tells us a lot about the relative productivity of that water body. Freshwater shrimp flourish in nutrient rich, alkaline waters. Shrimp require high levels of dissolved calcium in the … Continue reading




In North America there are over two thousand species; in Britain there are at least 430; while there are over 600 species in mainland Europe; over 200 in Australia; and even more the world over. Where they are found, the … Continue reading


Two-winged flies


The order of insects Diptera, Two-winged Flies, is made up of several thousand species on every continent with great variance of form and habit, occupying diverse niches. They can be broadly divided into aquatic and land-bred or terrestrial species. Only … Continue reading




Damselflies belong to the insect order Odonata. Members of the relatively primitive insect order are widely distributed from the tropics to the arctic. Worldwide there are in excess of 650 species of this insect order. The order Odonata is broken … Continue reading




Insects of the order Ephemeroptera are commonly known as Upwinged Flies or Mayflies. They are found in fresh water around the globe occupying both lakes and rivers with species adapted to several different niches. The mayflies number 200 species in … Continue reading




The free-living caddis belong to the genus Rhyacophila of the family Rhyacophilidae. They are mostly green in colour, though some are brown or grey, and generally between 6 and 18mm in length. There are several fly patterns dressed to imitate this group. Often fished in the Czech nymph style. Continue reading