The Dark JRS was originally created by Western fly fishing guide, Jake Ricks, to imitate a local clinger-type mayfly nymph. This now proven pattern combines properties of several proven fish catching nymphs into one super nymph. This exclusive RiverBum nymph pattern has proven to be the ultimate all around nymph in many fly boxes around the world. This fly effectively matches several varieties of mayflies and stoneflies and simply looks tasty to hungry trout. If you don't know what to try this is a great searching or prospecting nymph fly that seems to trigger strikes in all kinds of water.