Description
Stonefly Nymphs – The Year-Round Secret
Why Stonefly Nymphs are a must-have:
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Protein Power: These nutrient-rich nymphs are a primary food source for trout and grayling all year long.
- Easy Targets: As poor swimmers, they often lose their grip and drift downstream, becoming an effortless "snack" for waiting fish.
- Bottom Dwellers: Unlike many insects, they don't swim to the surface to hatch; they crawl to the shore. This keeps them in the "strike zone" near the riverbed for their entire life cycle.
J:son Tungsten Stonefly Nymph 3 Black (#8)
The Technical Heavyweight – Perla and Dinocras Specialist The J:son Tungsten Stonefly Nymph 3 Black in size #8 is a perfectly proportioned 20 mm imitation, featuring an integrated tungsten core. This "Medium" size is one of the most effective nymphs in the range, replicating the mid-stage growth of large stoneflies like the Large Black Stonefly (Dinocras cephalotes) or the mature stage of smaller black species.
Why this fly works:
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The Perfect "In-Between" Size: At 20 mm, this nymph is large enough to be noticed as a high-protein meal but small enough to be taken by average-sized trout and grayling. It is the ideal size for rivers where the massive 32 mm nymphs might be too intimidating.
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Rapid Depth Entry: The tungsten weight is optimized for the #8 hook size, allowing the fly to sink like a stone. It is designed to get into the "feeding zone" beneath the heavy surface currents of riffles and runs almost instantly.
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High-Contrast Silhouette: The jet-black coloration provides a sharp, clear profile against the riverbed or a bright sky. In technical water, this high contrast helps fish lock onto the fly even in turbulent, bubbly sections.
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Anatomical Mastery: Even at this reduced scale, J:son’s S3 design maintains industry-leading realism. The flexible legs and segmented wing pads move independently in the current, creating a "life-pulse" that triggers instinctive strikes.
Pro Tip: This is a world-class nymph for big grayling. Its weight and size make it an excellent choice for fishing deep "scoured" holes behind boulders. Use it as a single fly on a long leader or as the heavy "dropper" in a nymphing rig to ensure your flies are bouncing off the gravel where the fish are holding.

