About "Mystery Creeks": I love small streams, but some of my favorite little trout streams are too small and too fragile to publicize here. If you recognize one of these, you already understand why I'm keeping it a secret. These are the kinds of places that lose a little bit of their charm if you see someone else's week-old footprint, and I don't want to do that to them.
Closeup insects from Mystery Creek # 249
Male Rhithrogena hageni (Western Black Quill) Mayfly Spinner
View 15 PicturesI collected this spinner from the trail (old logging road) above a whitewater canyon on a small stream in the Cascades. I'm fairly positive on the ID: in Traver 1935 it keys out to Rhithrogena doddsi, which is now a synonym (Synonym: A former name of a taxon, usually a species. Entomologists frequently discover that two insects originally described as different species are one in the same, and they drop one of the names. The dropped name is said to be a synonym of the remaining name. These changes take a while to trickle into the common knowledge of anglers; for example, Baetis vagans is now a synonym of Baetis tricaudatus.) of Rhithrogena hageni. The penes (Penes: The paired genital structures of most male insects, which vary widely in form and are one of the main characteristics used for species identification.) differ slightly from the drawing in that book, but they're a very close match to drawing from the original hageni description in Eaton 1885.
I'm using its ID to put a species ID on a female dun and mature nymph collected on the same trip. I'm also using this one's ID for a specimen with seemingly identical reproductive anatomy from Montana.
Lastly, I have included here a couple pictures of the genitalia of a different specimen collected on the same evening, from the same river, and I think even the same swarm (although I don't recall that 100 %). They're angled a bit differently, and I couldn't locate the mid-ventral (Ventral: Toward or on the bottom.) spines, but I'm guessing I'm just seeing intra-species variation.
Female Rhithrogena hageni (Western Black Quill) Mayfly Dun
View 7 PicturesI was surprised by the olive cast on the body of this female Rhithrogena dun, which led me to mistake it for a western green drake (Drunella) in the field. I was pleasantly surprised to get a closer look and find something I hadn't collected yet. Its species ID is based on proximity to male spinner collected on the same trip, as well as physical similarity (size, tergite (Tergite: The top (dorsal) part of a single segment on an insect's abdomen when it consists of a single chitinous plate (sclerite), or an individual sclerite if the segment has more than one.) coloration, dark streaks on the femora (Femur: The main segment of an insect's leg close to the body, in between the tibia and the trochanter.)) to that specimen.
Recent Discussions of Mystery Creek # 249
Now this is what I'm talking about. Great write-up and photos!Reply
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