2. Amanita mortenii, day after collection and annotation, showing cap color change, Greenland.
of A. mortenii is 35 - 75 mm wide, campanulate
or conico-convex at first and subumbonate, eventually
planar with or without distinct umbo, glabrous, tacky to
dry, with a striate-sulcate margin. It is often
olive-gray to olive-brown to predominantly olive-yellow
at first with darker yellow-brown between striae. With
time, the cap changes color significantly to ocher,
ocher-brown, ocher-gray, or yellow-brown. The margin is
often paler. The flesh is white, sometimes sordid yellow
just below the cap skin, soft, and thin. The volva is
absent or as small, pale saffron "flakes" or as
pallid small patches with gray margins.
The gills are free to
narrowly adnate, close, very pale buff to off-white in
mass, becoming grayish with age. The short gills are
truncate to subtruncate to subattenuate, of diverse
lengths (often rather short), unevenly and sparsely
distributed, occasionally adjoining stem rather than cap margin.
The stem is 62 - 140 × 6 - 17 mm, hollow, exannulate, with relatively broad central
cylinder. The stem ranges from white to light gray; and
it is palest toward the apex, becoming grayish or pale
gray-brown near bruises and wounds. The flesh is white,
becoming slightly grayish with age and rather brittle.
The sac-like volva is submembranous, fleshy, flexible at
first, then rather fragile; it is appressed to or
adjoining the stem for about the lower third to half of the limb height.
The spores measure (8.5-) 9.5 - 13.0 (-17.0) × (7.2-) 8.5 -
11.5 (-15.0) µm and are globose to subglobose to broadly
ellipsoid (infrequently ellipsoid) and inamyloid. Clamps
are absent from bases of basidia.
This subarctic species tends to be
more olivaceous at first, but becomes more orange on
exposure and after collecting. Since the spore size also
becomes slightly less globose at the same time, I was
mistakenly under the impression for some time that there
were two taxa. When Mr. Borgen took the lower of the two
photographs a day after writing a description of the
fresh material, my error was revealed. The most recent
technical description of this species is by Tulloss and
Borgen (1996). For
comparison, see A. submembranacea (Bon) Gröger
and the other taxa cited on that page.—R. E.
Tulloss and T. Borgen Lindhardt
Knudsen & T. Borgen in Laursen et al. 1987. Arct. Alp. Mycol. 2: 244, fig. 3.
"Morten Lange's Ringless Amanita"
≡Amanita mortenii Knudsen & T. Borgen emend. Tulloss & T. Borgen in Tulloss. 1994. Mycotaxon 52: 353, figs. 31-32. [Amendment in error.]
The editors of this site owe a great debt to Dr. Cornelis Bas
whose famous cigar box files of Amanita nomenclatural information
gathered over three or more decades were made available to RET for computerization
and make up the lion's share of the nomenclatural information presented on this site.
Tulloss and T. Borgen. 1996. Mycotaxon 59: 419, fig. 1. [Correction of erroneous amendment.]
The following text may make multiple use of each
The field may contain magenta
text presenting data from a type study
and/or revision of other original material cited
in the protolog of the present taxon.
Macroscopic descriptions in magenta are a
combination of data from the protolog and
additional observations made on the exiccata during revision of the cited original
The same field may also contain black text, which
is data from a revision of the present
taxon (including non-type material and/or material
not cited in the protolog).
Paragraphs of black text will be labeled if further
this text is appropriate.
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 not directly from the
protolog of the present taxon and not cited as the
work of another researcher is based on original
research by R. E. Tulloss.
"TBORG" is used as an abbreviation for "in herb.
35 - 75 mm wide, at first often olive-gray to olive-brown to predominantly olive-yellow (2.5Y 7/6) with darker yellow-brown between striae and whitish margin and with disc having pale grayish tint (about 10YR 7/2), eventually ocher (near 10YR 6/6) or ocher-brown (10YR 6/4) or ocher-gray (near 10YR 5/5) or warm ocher (10YR 5-6/8) or tan (less vivid than 2.5Y 7/6) or yellow-brown (less vivid than 2.5Y 6.5/6 with margin paler, about 2.5Y 7/3) or gray-brown or cardboard brown, sometimes somewhat darker (grayer) over disc (e.g., 10YR 6-7/4), often paler toward margin [off-white or yellowish white to pale yellow (2.5Y 8/2-3) or pale grayish tan (10YR 7/4)], campanulate to conico-convex at first and subumbonate (in this form 24 - 52 mm wide and 19 - 40 mm high), eventually planar with or without distinct umbo, glabrous, tacky to dry, glistening when moist, dull to slightly shiny when dry, not hygrophanous; context white, sometimes sordid yellowish just below pileipellis, not discoloring when bruised or cut, rather soft and thin (e.g., 1 - 2 mm thick at mid-radius, 5 mm thick at stipe); margin striate-sulcate (0.25 - 0.5R), striation rather faint at first although long even then, slightly decurved to straight; universal veil absent or as small, pale saffron “flakes” or as pallid small patches with gray margins (eventually entirely gray).
free to narrowly adnate with decurrent line on stipe apex, close, very pale buff (slightly paler than 10YR 8/2) to off-white in mass, white to whitish in side view, becoming off-white (ca. “2B”) and then grayish with age, drying pale cream to pale grayish white to pale yellow or yellowish (3A2 or 4A3) to tan (5B4-5) to brown (a little browner than 5D5 or 5D7 or 10YR 6/4), with white [or at least in scattered places gray-brown (e.g., 10YR 7/3)] flocculose edge, rather narrow (3.5 - 8 mm broad), subventricose; lamellulae truncate to subtruncate to subattenuate, of diverse lengths (often rather short), unevenly and sparsely distributed, occasionally adjoining stipe rather than pileus margin.
62 - 140 × 6 - 17 mm, white to off-white to very pale yellowish to very pale gray brown to very pale brownish buff to buff to very pale gray-brown (10YR 7/3) to light gray (10YR 7.5/1), palest toward apex, becoming grayish or pale gray-brown near bruises and wounds, pruinose to pulverulent near apex, becoming appressed fibrillose below (and then fibrils bearing pigmentation (when present) with exposed white ground between them), occasionally with lower surface breaking up into appressed scales, lacking strangulate zone as in A. ceciliae (B. & Br.) Bas; context white, becoming slightly grayish with age, rather brittle, hollow, with relatively broad central cylinder (up to 5 mm or more wide) occasionally having cross walls that become grayish buff (near 10YR 6/2); exannulate; universal veil as saccate volva, submembranous, appressed to or joining stipe for about lower third to half of limb height, with upper tip of limb 30 - 60 mm from base of stipe, fleshy, flexible at first, then rather fragile, 0.5 - 2 mm thick, with exterior pallid at first, becoming pale gray to gray (near 10YR 5/1 or 10YR 5/5 or 10YR 6/2), at times with saffron tint in free limb, at times with yellowish-orangish-ochraceous to yellow-brown (e.g., 10YR 7/4-5) subpyramidal surface scales or spots or stains, paler toward stipe base (e.g., 10YR 8/1 to pale brownish buff to grayish white to white), inner surface off-white to pale gray (e.g., paler and purer gray than 10YR 6/2) or concolorous with exterior, with small whitish limbus internus placed at point of attachment between stipe and volval limb and at least sometimes white and floccose.
Odor lacking or almost so.&nbp; Taste mild.
Phenol - in stipe context, slowly pale reddish to pale salmon after 1 min., then vinaceous after 5 min.
40 - 110 µm thick, rather easily separating from pileus context in holotype, with gelatinized surface colorless, otherwise orange-brown in 3% KOH with pigmented region extending into pileus context; filamentous, undifferentiated hyphae 1.0 - 5.2 (-7.0) µm wide, branching, densely packed vertically, subradially oriented, partially gelatinizing below surface, totally gelatinized at surface; vascular hyphae 2.0 - 8.8 µm wide, irregularly disposed, infrequent or relatively common locally.
filamentous, undifferentiated hyphae 2.0 - 12.0 µm wide, branching, loosely interwoven singly or (often) in fascicles, sometimes with granular contents, with those of largest diameter having walls occasionally up to 0.8 µm thick; acrophysalides dominating except close to pileipellis, thin-walled or with walls up to 1.0 µm thick, broadly ellipsoid to ellipsoid to ovoid to broadly clavate to clavate to narrowly clavate to subfusiform, up to 148 × 63 µm; vascular hyphae 2.2 - 18.0 µm wide, uncommon to locally common.
bilateral, divergent; wcs = 40 - 55 (-70) µm; divergence at diverse angles, many at 90±°; subhymenial base including branching hyphae, subinflated branched elements, and inflated cells up to 65 × 27 µm or larger (irregularly distributed, broadly fusiform to narrowly clavate, often curved, diverging at angles from less than 30° to nearly 90°); filamentous, undifferentiated hyphae 1.2 - 6.5 µm wide, branching, densely interwoven in central stratum, in immature regions occupying much of trama, in mature material with rather common chains of short to moderately long inflated intercalary segments (fusiform to subfusiform to clavate, up to 56 × 18.5 µm); divergent inflated cells probably all intercalary, scattered to relatively common, single, thin-walled, broadly ellipsoid to ellipsoid to broadly clavate to clavate (up to 83 × 33 µm, mostly under 65 µm long), at many angles from aligned with central stratum to perpendicular to it, rather easily becoming free from original position in section; vascular hyphae 1.0 - 5.0 µm wide, branching, uncommon to scarce.
wst-near = 45 - 70 µm; wst-far = 60 - 90 µm; consisting of an interwoven structure of short and branching, uninflated to partially inflated to inflated hyphal segments (many roughly perpendicular to the central stratum), with basidia arising from all types of elements (dominantly from uninflated segments), with infrequent branches of uninflated hyphae parallel to central stratum in well rehydrated sections.
36 - 71 (-77) × 11.0 - 19.0 µm, thin-walled, dominantly 4-, but also occasionally 1-, 2-, or infrequently, 3-sterigmate, thin-walled, with sterigmata up to 13.3 × 4.2 µm; clamps not observed.
On pileus, exterior surface: very thin layer (10 - 25 µm thick) of gelatinizing hyphae in fascicles, yellow to yellow-orange to brownish orange in 3% KOH, with fascicles separated by spaces through which interior visible. On pileus, interior: filamentous, undifferentiated hyphae 2.0 - 13.0 µm wide, with most 4.0 - 9.0 µm wide, singly and in small fascicles, branching, occasionally loosely coiled or twisted, sometimes constricted at septa, with walls thin or up to 0.8 µm thick (in hyphae of larger diameters), plentiful to locally dominant; inflated cells terminal singly, at times slightly sordid, scattered to locally dominant, subglobose to ellipsoid to broadly clavate to clavate (up to 70 × 52 µm), with walls thin or up to 1.0 µm thick; vascular hyphae not observed. On pileus, inner surface: gelatinized, otherwise like interior. At stipe base, exterior surface: as on pileus, with most fascicles longitudinally oriented; filamentous, undifferentiated hyphae 3.2 - 5.0 µm wide, branching; vascular hyphae 3.2± µm wide, branching, not common. At stipe base, interior: filamentous, undifferentiated hyphae 2.2 - 15.0 (-18.2) µm wide, branching, loosely interwoven in fascicles (including few hyphae of large diameter) and singly, plentiful to locally dominant, some loosely coiled or with small groups of rather tight kinks closely spaced, thin-walled or with walls to 0.8 µm thick (especially in near-terminal segments), occasionally with slightly swollen intercalary segments; inflated cells dominant throughout much of tissue (especially in uppermost parts of limb) or locally scattered, terminal singly or in chains of up to four cells, often pale sordid or pale brownish or yellowish brown, globose to subglobose to subpyriform to broadly ellipsoid to ellipsoid (up to 78 x 69 µm) or broadly clavate to clavate to fusiform (up to 116 × 60 µm, but almost always with major diameter less than 80 µm), with walls thin or up to 1.2 µm thick; vascular hyphae 2.0 - 7.0 µm wide, scattered to rare. At stipe base, inner surface: gelatinized, often like interior, but occasionally consisting of remnants of very thin layer of longitudinally oriented, narrow diameter hyphae.
longitudinally acrophysalidic; filamentous, undifferentiated hyphae 1.8 - 10.5 µm wide, branching, plentiful to dominating, often in fascicles, with walls up to 0.5 µm thick; acrophysalides common to plentiful, subventricose to narrowly clavate to clavate, up to 220 × 55 µm (mostly under 160 µm long), with walls thin or up to 1.0 µm thick; vascular hyphae 1.2 - 8.0 µm wide, branching, unevenly distributed (locally uncommon to locally plentiful)
[451/23/12] (8.5-) 9.5 - 13.0 (-17.0) × (7.2-) 8.5 - 11.5 (-15.0) µm, (L = (10.1-) 10.3 - 11.8 (-11.9) µm; L’ = 11.0 µm; W = 8.9 - 10.6 (-10.9) µm; W’ = 10.0 µm; Q = (1.0-) 1.03 - 1.22 (-1.47); Q = 1.06 - 1.17 (-1.18); Q’ = 1.10), hyaline, colorless, smooth, thin-walled, inamyloid, subglobose to broadly ellipsoid, infrequent globose or ellipsoid, usually at least somewhat adaxially flattened, sometimes swollen at one end; contents mono- to multiguttulate to granular; apiculus sublateral, truncate-conic to cylindric, sometimes rather large relative to spore size; off-white (ca. 2B of Romagnesi (1967)) in deposit.
Not uncommon locally, subgregarious, in subarctic to low arctic habitat, at 10 - 75 m elev. On acid dwarf-scrub heath in fjords near Betula glandulosa with Empetrum nigrum subsp. hermaphroditum and Cladonia spp. or with grasses, Cladonia, and Stereocaulon or on gravelly soil among mosses near B. glandulosa with Cladonia, Cetraria, and Empetrum or scattered on dry heath among B. glandulosa and Empetrum sp or with B. glandulosa.
Ivittuut Municipality - “Ellerslie havn”
[61°19´N/48°8´W], 10 km E of Kangilinnguit/Grønnedal
on opposite side of fjord, 13-14.viii.1985 T. Borgen
85.133 (paratype, C).
Paamiut (Frederikshåb) Municipality - at head of
Eqaluit fjord, 25 km E of Paamiut [62°3´ N/
49°25´ W], 11.viii.1981 T. Borgen 81.119 (paratype,
C), 24.viii.1984 T. Borgen 84.172 (paratype, C),
29.viii.1985 T. Borgen 85.260 (RET 021-1;
TBORG), 24.viii.1986 T. Borgen 86.257 (RET 021-2;
TBORG), 10.viii.1993 T. Borgen 93.107 (TBORG),
19.viii.1993 T. Borgen 93.133 (RET 139-1, nrITS seq'd.; TBORG), 28.viii.1993
T. Borgen 93.167 (RET 139-2, nrITS seq'd.; TBORG), 27.viii.1984 T. Borgen
94.74 (RET 327-8; TBORG); Eqaluit at end of fjord
[62°4´ N/ 49°23´ W], 19.viii.1973 P. M. Petersen
73.319 (paratype, C); ca. main river,
0.5± km E from E part of head of
Eqaluit fjord, 22.viii.1998 T. Borgen 98.186 (RET
294-8, nrITS & nrLSU seq'd.).
Near Narssarssuaq - Rosenvinges Plantation
61°14´ N/ 45°32´ W], 29.vii.1983 H. Knudsen,
T. Borgen, & Jens H. Petersen [J. H. Petersen
150] (holotype, C). Qassit
Kangerluarsua, at head of fjord, 20.viii.1994
T. Borgen 94.45 (TBORG). Qinngua Valley - Taserssuaq Lk.
[60°16´ N/44°33´ W], 13.viii.1983 H. Knudsen, T.
Borgen & J. H. Petersen [J. H. Petersen 462]
(paratypes, C & L).
—R. E. Tulloss, T. Borgen Lindhardt and L. V. Kudzma
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Knudsen & Borgen
"Morten Lange's Ringless Amanita"
1. Amanita mortenii, fresh cap color, Greenland.
2. Amanita mortenii, day after collection and annotation, showing cap color change, Greenland.
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.