Morels and False Morels - Pezizomycetes p.p.
Morchella/Verpa - morels and false morels with smooth or pitted cylindrical caps.
Gyromitra/Helvella - brain mushrooms and elfin saddles.
Morchella - the highly prized choice edible spring morels. Some related species are shaped like large cups. Some are famous for growing in largest abundance the first spring after a forest fire. Morels are poisonous raw, so make sure to cook them well and not mistake them for the false morels, some of which could be deadly poisonous raw (or even cooked). Unlike Verpa, the stems are hollow, and the cap is attached to the stem more than just at the top, but at least for half the height of the cap and most often entirely. Traditionally morels come in black and yellow, but recent studies have shown that there are many different "black" species. "Black" morels have an "ant runway" trough between the cap and stem when held upside down (compare M. brunnea to M. americana) and their pits are elongated and vertically aligned. They are usually (but not always) darker than the yellow morels, that have rounder, more irregularly placed pits. Morels are probably mycorrhizal, but at least a few species, like the landscape morels, have long been spotted nowhere near trees (and M. snyderi, M. brunnea and M. populiphila have rarely been spotted in landscape habitats). Therefore morels are apparently also capable of being saprophytic and cultivation studies have had some success growing certain species of morel in captivity. Up to 10-20cm high.
M. importuna ('elata') - "landscape morel" - found in yards the spring after the ground is disturbed, causing some people to continually re-landscape their property. Usually clustered. The least yummy morel?
'Mel-8' - very similar, usually growing singly. As yet unnamed.
M. hotsonii - another landscape morel with more velvety ridges. Found once in Redmond, WA.
M. rufobrunnea - southern OR "landscape" morel, paler ridges, stains reddish brown. Like M. tridentina it is pale like a yellow morel but with pits shaped like a black. It is neither, but belongs to the basal clade, the ancestor of all morels. May fruit year round.
M. tomentosa - only shows up the first spring after a forest fire above 3000'. Dark, hairy, rounded ridges that lighten, grow bald and flatten in age, stem at first densely hairy and often dark. Sometimes greyish. Late spring through summer.
M. snyderi - most common black morel outside of recent burns (and to complicate matters, sometimes in landscaped areas). Pale colours when young. Stem often with ribs and holes, even when young. May grow in clusters. Early spring.
M. brunnea - less common "natural" black outside of recents burns but under hardwoods. Grows singly, more slender and more brittle stem than M. snyderi, with deeper ant runway. Early spring.
M. eohespera - similar under Englemann spruce, late spring.
M. tridentina (frustrata) - "black" morel that looks yellow (thus frustrating), but the pits are elongated and vertically arranged. Has an ant runway (subtle here). Late spring.
M. americana ('esculenta'/
Verpa - false morels with a cottony stuffed stem and a cap that only attaches to the stem at the top. The caps have different patterns than morels as well. Also poisonous raw, and sometimes even when cooked people have lost their fine motor control skills for a few hours. Nobody knows why. Like morels, also mycorrhizal but if their close relationship to morels is any indicator I wouldn't be surprised if they could also be saprophytic. Usually found in spring. V. bohemica is found a couple weeks earlier than morels.
Gyromitra - some species contain gyromitrin, which when consumed metabolizes to monomethylhydrazine (rocket fuel), so unless very well cooked they could kill you. But if you cook them the fumes (and possibly still the mushroom) could kill you. So don't. Other species are shaped like large cups. Thought be be saprophytic, but possibly also living a double life as mycorrhizal like the morels. Caps up to 10cm across or so. Usually stockier and meatier than the similar Helvella. Found in spring unless otherwise stated.
G. infula - saddle shape with a cleft. DEADLY. Unusual for appearing in the fall. Resembles Helvella but stockier.
Helvella - "Elfin saddles" because people imagine little elves sitting on the saddles. Don't confuse with Gyromitra. More species are found in the large cups. Mycorrhizal, at least. Found in spring under conifers or in mixed forests unless otherwise stated.
H. vespertina ('lacunosa') - black convoluted cap, grey lacunose (fluted) stem. Margin attached to stem, smooth under cap. <30cm high, usually <8cm. Fall (sometimes spring) with conifers.
H. dryophila - prefers oak, fruit trees and madrone, may have higher contrast black and white, <8cm tall (shorter stem). Fruits winter and spring. Another undescribed species may exist.
H. maculata - brown cap, fluted stem, cap edge not attached to stem, powdery underneath cap. <15cm tall. Fall.
H. elastica - saddle cap at obtuse angle (wide 'v'), brown, round stem, smooth and white under cap. Cap edge always rolls into stem. <4cm across <10cm high. Spring and fall.
H. compressa - saddle cap at acute angle (narrow 'v'), brown, round stem but powdery and off-white under cap. Young cap edge rolls away from stem. More solid stipe. Similar size. Spring and fall.
H. albella - darker (but not pitch black) and perhaps smaller than H. compressa. Less powdery under cap? Fall.
There totally would be a morel colour photo book out there except we only just realized there are more than two morels.