Olive text indicates a specimen that has not been thoroughly examined (for example, for microscopic details) and marks other places in the text where data is missing or uncertain.
The following material is based on original research of R. E. Tulloss.
60 -82 mm wide, color in button unknown, at start of
sporulation moderately saturated slightly grayish
red-brown or medium brown over disc and gradually
becoming tan then beige then pale beige toward
margin, broadly companulate then convex to
planoconvex, sometimes umbonate, tacky and shiny
when moist, matte when dry;
context 4± mm thick over stipe,
whitish to off-white for the most part, not
discoloring after exposure, narrowing (?)evenly
toward margin for up to ca. 55 - 65% of pileus
radius, then membranous; margin
nonappendiculate, striate (0.15 - 0.45R);
universal veil absent or as unevenly
distributed occasional thin white to gray flakes or
small patches, smooth, membranous, with underside
pale tan at first, at first detersile, sometimes
becoming glued to pileus surface, often
with raised or distinctly upcurved edges.
free, without decurrent tooth on stipe,
subcrowded to crowded,
cream in mass, white to off-white
in side view, 3.5 - 6 mm broad;
lamellulaeae truncate to rounded
truncate to subattenuate to attenuate, of diverse
lengths, unevenly distributed,
apparently infrequent in some exsiccata.
80 - 130 × 6 - 7 mm, white or whitish or pale
orangish tan for most of
length, white inside universal veil, becoming
brownish where handled, narrowing upward, slightly
flaring at apex, with upper 30±
mm pulverulent and concolorous with ground color,
below pulverulent region with some
raised fibrils where handled or with such fibrils in
light yellow-brown to medium brown snakeskin
pattern, with pattern becoming darker toward stipe
base (possibly from handling), with lowest
50± mm undecorated;
offwhite except pale orangish white near stipe
surface, no bruising or staining observed, stuffed
white cottony material, with central cylinder
2± mm wide; with larval tunnels
universal veil as thin membranous saccate
volva, originally white, becoming pale gray to gray
with age, sometimes staining rusty orange,
asymmetrically divided around stipe base,
tearing and fragmenting with age, with highest point
on fragment 12 - 27 mm from stipe base, with
greatest width 8.5 - 11 mm, less than 1 mm thick,
attached only at stipe base, with no apparent
Odor indistinct. Taste not recorded.
bilateral, divergent; filamentous undifferentiated hyphae ??; inflated cells ??; vascular hyphae 4.0 - 5.3 μm wide, common at least locally.
RET: [20/1/1] (8.5-) 9.0 - 12.2 (-14.2) × (6.5-) 7.2 - 10.7 (-11.6) μm, (L = 10.3 μm; W = 9.2 μm; Q = (1.08-) 1.10 - 1.30 (1.40); Q = 1.18), hyaline, colorless, smooth, thin-walled, subglobose to broadly ellipsoid, infrequently ellipsoid, adaxially flattened; apiculus sublateral, cylindric; contents monoguttulate with additional small granules; color in deposit not recorded.
Solitary or as a pair. In dark loam or in dark loam
of mixed forest with Fagus, Quercus,
Tsuga canadensis, and Pinus.
CONNECTICUT—Middlesex Co. - Moodus,
22.viii.2008 Bill Yule s.n. [RET 8-22-08-F]
(RET 421-6, nrITS and nrLSU seq'd.); Salmon River
St. For (W sect.) [41.5492° N/ 72.4514° W, 37 m], 28.viii.2009 Linda s.n.
(RET 437-10, nrITS seq'd.). New London
Co. - Colchester, Day Pond
[41.5569° N/ 72.4183° W, 134 m],
31.vii.2015 J. Wheeler s.n.
[Tulloss 7-31-15-L] (RET 703-7, nrITS &
The present species is known from three
collections. The species was segregated by
it unique nrITS sequence.
Morphologically, it appears to be related the
group of taxa including A. rhacopus. Based on
derivation of a sequence from its nrITS locus,
it appears strongly genetically differentiated
from all taxa of sect. Vaginatae having
sequences presently deposited in GenBank.
It is also strongly differentiated genetically
from all non-GenBank-deposited data in the RET
The same level of genetic separation (a minimum of
over 2%) is also true for the nrLSU sequence
derived from the A. sp-N61
Each spore data set is intended to comprise a set of measurements from a single specimen made by a single observer;
and explanations prepared for this site talk about specimen-observer pairs associated with each data set.
Combining more data into a single data set is non-optimal because it obscures observer differences
(which may be valuable for instructional purposes, for example) and may obscure instances in which
a single collection inadvertently contains a mixture of taxa.