Right now, the large stonefly species in rivers and streams are almost at their mature size. Here are two of my own patterns I've been waiting to try out. Swart's Supernatural Stones. Golden Stone: Female Ovipositor: #8 Salmonfly: Female Ovipositor: #4 Skwala Supernatural Stone coming soon. And these two nymphs below aren't my own pattern, but I tied them; a local favorite. Mercer's Poxyback Beaded Biot Golden Stone Mercer's Poxyback Beaded Biot Salmonfly.