When does the Patagonian Stonefly (Large) hatch?

October–January, typically 11:00–18:00. It starts from about 8°C, peaks around 13°C and tails off by 18°C.

What flies imitate the Patagonian Stonefly (Large)?

Pat's Rubber Legs, typically on a #6–4 hook.

How big is the Patagonian Stonefly (Large)?

Nymph stage: 20–25mm. That matches a #6–4 hook.

Stonefly · Aquatic insect

Patagonian Stonefly (Large)

Klapopteryx kuscheli

Size

20–25mm

Hook size

#6–4

Outside the hatch

Nymphs are in the water all year, long before and after the hatch window — the season and temperature figures on this card describe when the adults emerge, not when this stage is available. It very nearly always is.

How fish feed on it

A stonefly nymph crawls rather than swims, and when its time comes it crawls out — up a rock or onto the bank — rather than hatching in open water. So there is no emergence to fish, and no rise to watch for. What there is, is a big, well-armoured nymph living in the stones all year, dislodged by heat and spate and clumsy wading, and worth every bit of a trout's attention when it comes loose. Fish it on the bottom in the fast, broken, well-oxygenated water it needs.

Flies that imitate this

Pat's Rubber Legs

Ecology

Rivers & stillwaterSpate riversAlpine riversFreestone riversClean water only

Where you'll find this

PatagoniaPresent

Present throughout