|Expert links:||"Rozites" caperatus||C. violaceus||Hypogeous|
If you thought I was crazy for trying to show you how to identify Russulas, you're really going to think I'm crazy now. Cortinarius is possibly the largest genus of macrofungi, with thousands of species found so far, and more being described all the time. The PNW has more than 400 known species, and counting. This is historically the most difficult genus to identify to species, with most people who can otherwise identify almost anything else willing to say "It's a Cortinarius, who knows?" (It is also not uncommon for someone to think that of Russula, Inocybe, Psathyrella and the Entolomataceae family). Learning Cortinarius is often saved for last (I did!), but there are many interesting Corts that can be identified without a microscope and you can learn at least something interesting about most of them that you find. Many of them are quite beautiful - there are literally hundreds of purple Corts, for instance.
With one important exception, Cortinarius is identified by having a web-like cortina in place of the regular partial veil which is usually a fleshy membrane. Many other coloured spored genera have also more or less developed a cortina, but Cortinarius will also often have a rusty orange tint to their brown spores and is almost always found on the ground, not on wood (they are mycorrhizal). Mushrooms with rusty orange spores and a cortina growing on wood usually belong to Gymnopilus. Phaeolepiota spores can look bright like Cortinarius too. If the spores lack the orange tones and are ordinary brown, you might not recognize one but might mistake it for Inocybe or Hebeloma.
The famous "cortina" cobweb veil, covered in rusty orange brown spores. Less than half of it is still attached.
Seeing rusty threads near the top of the stem can be a clue that your mushroom had a cortina with rusty spores (see the photos of C. violaceus).
Historically, because there are so many of them, Cortinarius was broken up into a few subgenera. As modern molecular analysis has started to be done, we now realize that this really isn't the way to divide up the genus, as the members of each subgenus are not necessarily related to each other. I will address this as we go through them to give you an idea of what is known about the real relationships of the mushrooms so far. These subgenera, however, are still a useful way to think about the genus, since it forces you to notice important things about the mushroom.
We always say that it is best to have many different samples of a mushroom, young and old, to identify it correctly, but this is especially true of Cortinarius. You need to find young ones, as the colour of the young gills is often one of the only distinguishing features. By the time those rusty brown spores mature on the gills, any delicate lilac or yellow colour will be lost. Another feature some Corts have is a universal veil that may leave colourful membranous material on the stem. Some also have interesting odors. Some glow in UV light!
As usual, unless otherwise noted, these species may be found
in conifer or mixed conifer/
There are many more species than are described here. There are some cryptic species (several species masquerading as one, that cannot reliably be told apart without DNA sequencing). Reports on scarcity are guesses at best, since some species are seen often but not recognized. Some of the most common ones, in fact, are missing here, because the task of sorting out local Cortinarius is daunting in any location. We are fortunate to have Dr. Joe Ammirati of the University of Washington in our region, who is one of the few experts on Cortinarius in the world and helping to solve the mysteries of Cortinarius for us.
|Identifying Corts in the spring is much easier - there are much fewer species: some common ones and their traditional subgenus are: C. thiersii (D), C. vernicosus (M), C. subolivascens grp (B), C. parkeri grp and C. clandestinus grp (L), C. vernus grp - C. ahsii grp - C. brunneovernus grp - C. flavobasilis grp (T). However, almost anything might fruit in spring under the right conditions.|
Key to Cortinarius "types", showing the background colour of each section (to help you not get lost).
"Rozites" caperatus - Gypsy mushroom - One of the only Cortinarius with a regular veil instead of a cortina. It turns out to be a true Cortinarius that just happened to evolve a membranous veil, but it is unclear how. You will probably look for it on a different page, but the rusty spores and growth on the ground still point to Cortinarius. Not hygrophanous, but sometimes with a hoary sheen to the cap. Resembles many poisonous Inocybe and Hebeloma. (Section /Rozites).
Cortinarius violaceus - Let's start with everybody's favourite, the mushroom that got me wanting to identify mushrooms. Who can look at this and not want to know what it is? An entirely violet-black mushroom with a cap that has a unique dry, rough, velvety look, and with beautiful rusty spores, here shown caught in the remains of the cortina on the stem. This species is so different from every other Cort (not to mention every other mushroom anywhere) it is in its own section. (/Cortinarius)
Hypogeous - a few species are evolving into truffles and remain partly underground. These are different than the gastroid corts that are smaller and misshapen. They are notable for their large size and the extremely tough, elastic cortina that does not break easily. Many are in section /Calochroi, but all are Phlegmacium-like. They are usually found in the spring.
C. magnivelatus - white, thick white veil hardly ever breaks. (/Calochroi)
C. wiebeae - similar, gills browner (Phlegmacium section /Varii?)
Dermocybe - The red, orange, yellow or olive-yellow gills have a special aura of brightness about them when young, and they have a stature or "look" about them that you can learn to recognize. The caps are dry and not hygrophanous. Small, usually <5cm. KOH oftens turns parts of these mushrooms brilliant colours, which can be used to help identify a species. This is a real subgenus with all the mushrooms closely related to each other.
So many Cortinarius are beautifully coloured that
you may mistake a "regular" Cort for one of these, especially since the orange
spores eventually colour the gills of most any Cortinarius a nice bright
orange. But throw a bunch of Dermocybes in boiling water and the water will soon become the
colour of the gills. Throw some wool into the pot, and the wool will be
permanently dyed. You can even add mordants to the water and/
There are almost 40 species of Dermocybe found in the PNW so far, in great need of study. Until then, here are a representative sample of some of them. Each one may have lookalikes. Species with similar coloured gills are not necessarily more closely related to each other than they are to those with different coloured gills, but it is an important feature to note.
Not a Dermocybe - just the regular Cortinarius rusty gills. Cap subtly different. Stem is too white.
Subtly brighter mature gills of Dermocybe (C. cinnamomeus). Cap and stem are also different. Young gills without spores show this best.
C. californicus can look like a faded C. neosanguineus, but it is hygrophanous and really a Telamonia. It can be entirely reddish-brown.
Red young gills.
C. ominosus ('semisanguineus') - dull brown to red cap, bright red gills, yellowish-brown stem. Lower stem glows in UV light.
Olive-yellow young gills
Yellow young gills - this list is especially incomplete
C. croceus grp - bright yellow young gills turn orange and then resemble the cinnamomeus grp. Often yellow stems.
C. aureifolius var hesperius - yellow gills in sandy soil, resembles an Inocybe.
Orange young gills - this list is also especially incomplete
Myxacium - These mushrooms have viscid stems as well as viscid caps (the caps are smooth and not hygrophanous). Some have very bitter cap slime you can easily detect if you touch it to your tongue. The stems are usually cylindrical. (If you can't tell for sure if the stem is viscid, Phlegmaciums with viscid caps but usually dry stems, will usually have a clavate or bulbous stem).
When they are old or dry the stem will not be sticky anymore. You might be able to detect that the stem used to be viscid by debris that is stuck to the stem (see the C. vernicosus photo) just like you can sometimes tell a formerly viscid cap from debris that is stuck to the cap, but this does not always work. Not every 'Myxacium' ended up being related to each other, so some have been moved to other sections.
C. collinitus (muscigenus) - orange-brown cap, white young gills, purple young stem, 3-8cm. Resembles C. seidliae, below.
C. mucosus - orange-brown cap, whitish young gills, white stem (no purple). <10cm. See C. brunneoalbus, below.
C. pinguis, a related gastroid Cort.
The closest relative of Myxacium, and still considered part of that subgenus, but microscopically lacking "clamp connections". Occasional honey odor in the base of the stem of some species, but it's unclear which.
C. seidliae grp ('stillatitus') - 2 sister species, cap wrinkled and darker than C. muscigenus, but not quite as dark as C. vanduzerensis.
C. brunneoalbus ('mucifluus') - no purple, macroscopically very similar to C. mucosus but smaller and more slender and with a paler cap.
C. pavelekii - related gastroid.
The following groups are unrelated but share the characters of Myxacium.
Members are usually purple or yellow capped, unlike the orange-brown caps of the previous groups.
C. 'salor' group - lilac young cap (fading to yellow-brown), young gills and stem. 3-8cm. We don't have C. salor, but we have a lookalike relative as well as a 2nd species alone in a distinct section.
Small, ~2.5cm, sometimes larger, pale cap edges, very bitter slime on cap cuticle if you stick your tongue on it.
C. causticus grp - a dozen or more orange-brown capped species (else whitish), of which our most common might be C. causticus.
C. pluvius grp - a few species, like C. pluvius, have brighter, possibly yellowish cap colours.
C. 'crystallinus' - one species has a whitish cap, but we don't know its real name.
Phlegmacium - Viscid, usually smooth caps, but usually with dry stems. This section will cover those with club-shaped stems. Some people separate out those with abrupt, marginate bulbs at the bottom of the stem into a separate group, Bulbopodium, and genetics has shown that many of those are indeed related to each other, so I will cover them separately. This section has stems that simply widen at the bottom. Here, I will also cover some very stocky species with especially thick stems (the entire stem).
Myxacium, above, also have viscid stems. If it's hard to tell the difference, they will usually have cylindrical stems that don't widen at the bottom. Look for debris stuck to the cap and/or stem to determine if an old dry specimen used to be sticky in that area. KOH turns many Phlegmaciums (and Bulbopodiums) yellowish, but sometimes other bright colours which can aid in identification.
This is an especially confusing traditional subgenus. While many species are actually somewhat related to each other, and there is still a rather large Phlegmacium section, many others were moved to a large number of additional sections that have been created. A sticky cap and dry clavate stem has evolved somewhat independently many times.
First, some of the species that seem to be related to each other comprising what I think of as the modern definition of subgenus Phlegmacium. At first, I am excluding species with very stocky stems. It is a large subgenus, so it has been broken into sections.
C. papulosus - orange-brown disc with paler margin. Brownish bands on the stem. Young gills and flesh white. Boreal.
C. castaneicolor - very young gills & flesh lilac. Brownish bands may be glutinous resembling a viscid stem.
C. luteobrunnescens - yellow disc with paler margin, brownish glutinous stem bands. (All Phlegmacium section /Elastici)
C. pallidifolius (cliduchus?) - similar orange-brown (to yellow-brown) cap, white young gills and warm brown stem banding, but cap of uniform colour. (Phlegmacium unique section)
C. pinophilus - tan to yellow brown cap, w/o stem banding, best differentiated by a unique microscopic cap cuticle. (unique clade)
C. pini - also similar, under conifers, best differentiated by cap margin that is hygrophanous, streaky and/or corrugated. Lilac young gills. (Phlegmacium unique section)
C. variosimilis grp - orange-brown cap, white woolly stem sheath, pale lilac young gills. KOH yellow on flesh. 2 genetic species. (Phlegmacium section /Varii)
C. argutus - whitish, odorless, stem veil remnants glow in UV light. Hardwoods. Thinly viscid. Almost silky. Possible slightly rooting stem.
C. patrickensis - odor of green corn. (Both Phlegmacium section /Arguti)
C. albofragrans - white, cylindric stem (bigger than C. 'crystallinus'), flowery odor like C. citrinifolius, next. Under oak. (Phlegmacium unique section)
C. citrinifolius ('percomis') - yellow cap, smells sweet, flowery or lemony. The clavate stem may be viscid. (Phlegmacium section /Percomes)
C. immixtus - olive-brown cap, olive-yellow gills and pale stem. (Phlegmacium section /Phlegmacium)
C. beugii - olive-yellow-brown species with oak and a green KOH reaction. Both difficult to ID when the colours fade to brown. (Phlegmacium unknown section)
This next bunch are not closely related to the other Phlegmaciums no each other, and have been moved to different sections.
C. occidentalis ('mutabilis') - all purple, staining deeper purple where cut! Stem flesh wine-red in iodine (I+). (/Purpurascentes)
C. subfoetidus - more intense purple than C. 'salor', disc fading to tan, lilac sheathed stem, sugar odor! (/???)
C. leucophanes - creamy tan cap, pale rose-tan young gills. Not quite as pale as C. argutus, above nor with the rooting stem. (/Lustrati)
C. oregonensis - purple cap with brown disc, purple young gills and purple stem that may be viscid. (/Lustrati)
C. subtortus grp - similar olive-yellow cap and gills and bitter taste, but interesting cedar like odor. Two unnamed local species. (/Subtorti)
Next, viscid species with uniformly thick and stocky stems, caps sometimes >10cm across. If the stem is not stocky, hopefully the cap will still be unusually large.
C. balteatus group - thick stocky stems, barely viscid, greyish-brown with various amounts of lilac on the cap, young gills and stem. Includes C. balteatus, balteatocumatilis (=lilacinocollosus?), durus (=badiolatus?), spadicellus ('variicolor'), sobrius, 'myrtilliphilus', sp. 44. (Phlegmacium section /Phlegmacioides)
C. vespertinus - barely viscid at best, brown cap, milky-coffee young gills, thick spindle shaped white stem, resembling the Telamonia C. distortus but not hygrophanous. (unique clade)
C. superbus - stem is very patchy and club shaped, smells of green corn. (Phlegmacium section /Percomes)
C. ponderosus - huge, scaly stem AND CAP! Yellow shades. Up to 30cm! Unpleasant odor. (unique clade)
C. crassus - occasionally viscid (otherwise keys out in Leprocybe), thick stemmed species with a hairy cap and pleurocystidia. Pale young gills. (/Crassi)
Bulbopodium - these mushrooms have long been considered part of Phlegmacium and not really a separate group, but for convience, all of the very marginate bulbed Phlegmaciums are grouped here to find them easily. The top of the stem is not as thick (hard to tell when very young), unlike the truly thick-stemmed species (compare C. balteatus with C. subolivascens). They are somewhat unreliably separated by having either white, lilac, yellow or olive-tinged young gills. The C. calochroi group below can be confused with almost all of these species, so be sure and consider them. All are usually from 3-8cm across, occasionally larger.
I will list the section name of each species, and if it is not part of the core group of Phlegmaciums, the section name will be in bold (e.g. /calochroi).
C. riederi (pseudoarquatus/
C. glaucopus group species are unrelated but some look similar. (/Phlegmacioides)
C. subolivascens grp - spring, at least some species at high elevations, sometimes entirely streaky purple. (/Phlegmacioides)
C. montanus (sphagnophilus/
C. multiformis - whitish young gills (unlike C. variosimilis), bright orange-brown cap, possible honey odor. (/Multiformes)
C. callimorphus - cap turns red in KOH, no odor.
C. rufoallutus - stem stains red-brown.
C. caesiolamellatus - blue young gills & stem apex, honey odor, spruce & pine.
C. pallidirimosus - creamy yellow streaky cap, honey odor, with birch.
"/Calochroi" - these bulbous mushrooms are not related to all the other Bulbopodiums, but certainly look like they are. In fact, some are very hard to tell apart from the other Bulbopodiums.
C. piceae (calochrous ssp. coniferarum) - pale lilac gills when young but brighter yellower cap than C. glaucopus grp. No odor unlike C. multiformis grp. Often a bulb.
C. 'corrosus' - southern calochroi species.
C. perplexus - also southern, rosy pink KOH reaction. Oak.
C. olympianus - completely pale lilac, does not stain dark purple like C. purpurascens nor turn brown. Turns bright red in KOH.
C. guttatus - yellow to olive-yellow cap, young gills and stem, smells sweet like a dingy, bulby C. percomis. Yellow-green colours make this and the next group resemble C. montanus.
luteicolor grp (cupreorufus/
Sericeocybe - recognized by a dry, silky, satiny cap sheen that is not hygrophanous, often with lilac colouration somewhere. Not all 'Sericeocybes' ended up being related to each other so some have been moved to other sections. Usually up to 5 to 10cm across.
First, the /Anomali section of Sericeocybe, considered some of the "real" Sericeocybes. Often smaller and more slender than the others. We may have a dozen species or more, many of them still unnamed.
C. anomalovelatus grp - entirely lilac when young like a small C. alboviolaceus, cap fades to brownish to resemble a pale C. caninus, stem often somewhat banded with pale fibres as seen on the left. At least eight species in this group!
C. caninus group - darker, brighter, brownish silky caps lacking lilac tones even when young, lilac stem and young gills. No stem banding. Resemble C.malachius, below.
C. caesiifolius - C. caninus with dark stem banding, sometimes more fibrillose cap than the others..
Some Telamonias have brown and/or lilac caps and red stem banding as well, but they usually have hygrophanous caps that aren't silky.
Similar silky-capped mushrooms, that stand out due to unusual odors or colour staining.
The following sure look like Sericeocybe but are actually Telamonias that look much more interesting than your average Telamonia. Again, usually up to 5 to 10cm.
C. alboglobosus (pinetorum) - missing any lilac, unlike C. alboviolaceus. (Telamonia section /Niveoglobosi)
C. alboviolaceus - silver lilac like the C. anomalovelatus group but usually bigger, lilac tinge to young gills, cap stays lilac, no bands. Hardwoods. (Telamonia section /Firmiores)
C. traganus - entirely lilac like C. camphoratus but smells like pears! Darker lilac than C. alboviolaceus. Brown flesh. (Telamonia section /Tragani)
C. venustus group - sweet pear odor, paler lilac and/or tan colours and white flesh. Includes C. venustus, C. calopus, C. fructuodorus and 2 unnamed species. (Telamonia section /Telamonia)
Some species I cover in Phlegmacium are only thinly viscid, which could be missed in older fruitbodies, such as the C. balteatus and C. argutus groups. They could be mistaken for Sericeocybes.
First we'll look at the true Leprocybes, and then the unrelated Corts that look like them.
C. clandestinus - black scales at least in the cap centre. Yellow-green universal veil remnants that can look like a volva. Spring and fall species.
C. clandestinus (non scaly spring snowbank variety) - formerly called C. subalpinus n.p., it sequences the same and only deserves variety status. Also with a volva, orange-brown with subtler black scales.
C. atrosquamosus - more likely to have black scales with olive, but may look very similar, as it does here.
C. parkeri - looks like a Telamonia with a smooth hygrophanous cap. Yellowish volva. Also spring.
These Corts are smooth capped, somewhat hygrophanous Telamonias, but might be mistaken for Leprocybe because of their positive UV reaction and similarity to C. parkeri.
C. ahsii's veil glows in UV (shown), C. colymbadinus' entire fruitbody glows in UV, but it doesn't have the volva of C. parkeri.
C. flavobasilis/bridgei - similar spring Telamonias with yellow stem base which glows orange in UV.
These next species are also not Leprocybes, but do have non-hygrophanous hairy or scaly caps. This next group usually have thick stems (so do a few viscid capped Phlegmaciums). One of these stain colours when cut. Microscopically, C. crassus and C. 'rubicundulus' share (along with C. violaceus) interesting cells called "cystidia" on the faces of the gills (not just the edges) which hardly exist in any other Cortinarius. Cap sometimes exceeding 10cm.
C. balteatus group - thick stocky stems, barely viscid, greyish-brown with various amounts of lilac on the cap, young gills and stem. Includes C. balteatus, balteatocumatilis (=lilacinocollosus?), durus (=badiolatus?), spadicellus ('variicolor'), sobrius, 'mytrilliphilus', sp. 44. (Phlegmacium section /Phlegmacioides)
C. crassus - nondescript if not for the thick stem and hairy cap. The sub-species shown smells like green corn. Pale young gills. Sometimes viscid! (/Crassi)
Some more unrelated species (to Leprocybe and to each other), also the typical <10cm across, sometimes have the Leprocybe look, some with interesting odors:
C. callisteus - usually bright orange with small scales when fresh, smells of hot motor oil! Stem often bulb shaped.
C. kroegeri ('limonius') - finely scaly?, hygrophanous like Telamonia, but usually yellow-orange. Yellow veil like C. rubellus but cap not as pointy and gills closer together. Stem often cylindrical. (/Limoni)
C. cacao-color - cocoa coloured everywhere, tapered stem. Large. Often has a nutty odor. Telamonia
C. fillioni (valgus) - dark with subtle cap fibres, best ID'd by the odd radishy odor. Strongly resembles the C. brunneus grp. It is a Telamonia.
These next few are yellow or orange-brown mushrooms. Somewhat umbonate, sometimes with a radish-like odor and coloured flesh inside, not pale. There may be yellow velar material on the stem and cap edges, unlike their lookalikes that do not have a coloured veil. One is in a clade of deadly poisonous mushrooms, due to the toxin Orellanine. C. rubellus is deadly and a true "Orellani", but C. gentilis/saniosus, although they resemble one, are actually Telamonias (after all, the cap is smooth and somewhat hygrophanous).
Telamonia - the largest and arguably the most boring section of drab mushrooms with dry, smooth, hygrophanous caps. Being hygrophanous, the shade of brown can vary dramatically depending on age so they have a more inconsistent cap colour than the other groups, but they seem to come in 3 general colour schemes and 3 sizes: orange-brown, brown with violet and dark to pale ordinary brown. The small ones might average ~2.5cm, medium ~5cm, and large up to 8-10cm. The caps are usually slightly umbonate and there is often a universal veil of white or coloured material that may leave material on the stem. KOH will turn many of the heavily pigmented species almost black. Telemonias are actually mostly related to each other, along with a few others that were traditionally placed in Sericeocybe.
First of all, I will deal with a few that look like Telamonia but are actually not related. For the sea of similar Telamonias I will try to sort them out by placing them into a couple of colour groups - those with red coloured veils, those with bright orange tones and those without. Those ordinary brown Telamonias can sometimes be differentiated by violet tones or red banding on the stems, and also by their size.
C. kroegeri ('limonius') - finely scaly?, hygrophanous like Telamonia, but usually yellow-orange. Yellow veil like C. rubellus but cap not as pointy and gills closer together. Stem often cylindrical. (/Limoni)
C. renidens - barely a cortina (it's rarely noticed). Orange-brown like the smaller C. gentilis. Medium. Also compare the yellow-orange-brown C. obtusus and C. parvannulatus (/Renidentes)
C. obtusus grp - umbo, yellow-orange-brown, iodine odor? Whitish stem, sometimes striate margin. Small to medium. (/Obtusi)
Telamonia s.s. - OK, here goes. Unfortunately finding your Telamonia in this large group of related and similar drab mushrooms is not going to be easy. There's even a good chance that you have an undescribed or little understood species that is not yet documented and not even in this list.
These first few have reddish stem banding from the red universal veil that, when fresh, rescues them from obscurity. Mostly boring brown, sometimes more orange-capped. Difficult to ID if the banding has washed or rubbed off. These species are from unrelated sections of Telamonia and beyond. Also consider the brown capped, red banded Sericeocybes.
C. boulderensis - Small to Medium, <4cm.
C. badiovinaceus - KOH turns the bands purple in all species but this one, which is not a Telamonia. Medium, <6cm. (/Fulvescentes)
Next, the orange-brown species.
C. armeniacus - like C. renidens, but with a cortina & white stem, or like C. laniger but brighter cap and paler gills. Bulbous stem. Medium.
C. parvannulatus - cedar odor, different colour than C. gentilis with a ring of material left on the stem. Small.
Also consider C. colus above, with stem banding.
These next species are medium sized with noticeable violet tones, at least when young. Medium sized species without violet tones will come next, and finally small Telamonias (with or without dark violet colours). Also consider some species in the C. brunneus group, below.
I'm afraid most of the rest are "just brown", and can be dark or light depending on how much moisture the cap has retained (they are hygrophanous after all). Those in this first group are mostly medium to large (>5cm). I seem to commonly find similar species that aren't any of the ones labelled here, so identifying some species in this group can be problematic.
C. venustus group - sweet pear odor, pale lilac and/or tan colours and white flesh. Includes C. venustus, C. calopus, C. fructuodorus and 2 unnamed species. Sometimes they look like Sericeocybe. (/Telamonia)
C. duracinus - similar, with a long rooting stem. Large.
C. subbalaustinus - streaky cap, no veil sheath, no rooting stem, nondescript.
C. cacao-color - cocoa coloured everywhere, tapered stem. Large. Often has a nutty odor and a scaly cap like a Leprocybe. See C. fillioni.
C. fillioni (valgus) - dark with subtle cap fibres, best ID'd by the odd radishy odor. Strongly resembles the C. brunneus grp and C. cacao-color.
C. brunneus grp - Classic boring medium-large Telamonia, cap & stem brown, white veil. (C. valgus has an odor and cap fibres).
C. athabascus - coastal, lilac tones in youth, persisting in the stem flesh.
C. bovinus grp - fresh cap is paler, club stem base.
C. uraceus - like C. brunneus, but darkens from greenish-brown to black in age. Medium.
C. nauseosouraceus - dark brown with yellow tinges, strong unpleasant smell.
C. parkeri - actually a Leprocybe but with a smooth hygrophanous cap. Yellowish volva. Also spring. Similar to Telamonias C. ahsii & C. flavobasilis, which also glow.
Formerly in Leprocybe. Spring, medium. Stem often paler than in C. brunneovernus, very similar to C. parkeri. C. ahsii's veil glows in UV (shown), C. colymbadinus' entire fruitbody glows in UV, but it doesn't have the volva of C. parkeri.
C. flavobasilis/bridgei - much like C. ahsii, but with yellow stem base which glows orange in UV. Spring. Medium.
I'm afraid some of these last small (~2.5cm) dull brown Telamonias are the most difficult of all to tell apart. Sometimes there is a hint of violet in the caps and stems like the larger C. evernius.
C. flabellus ('flexipes') - usually dark cap, umbonate, odor of geraniums, white veil material on cap and stem.
|The last group are difficult to
C. casimiri (shown above) has a wrinkled cap, distant red-brown gills and white wooly veil remants all over the stem.
C. alnetorum (with alder) has a darker cap and flesh (and distant gills and white wooly veil remnants on the stem).
C. decipiens has a dark cap (at least in the centre) but fewer white veil remants on the stem, closer gills.
C. chrysomallus has bright yellow veil remnants on the stem.
C. bibulus - beautiful violet all over, pointy umbo, few widely spaced gills. Alder. Small!
|Also consider the red-banded species and whether or not it may have once had purple or orange tones but just faded. Good luck to you.|
I eagerly await the chance to tell you that a specialized publication on Cortinarius of the PNW has been created. There are European publications, such as Cortinarius Flora Photographica by Brandrud et. al., but even if you can find it it will cost you more than $500, and new volumes are still being added. The already mentioned Fungi of Switzerland Volume 5 has a particularly large collection of over 230 Cortinarius, each with a colour photo and drawings of microscopic features.