The description that follows is based upon the treatment of this species by Bas (1982).
The cap of A. hyperborea is up to 60 mm wide, convex to plano-convex, probably originally umbonate, dull to somewhat shiny, thin-fleshed, with a rather strong and dense sulcate margin (20 - 50% of the radius). The cap is white in the center. The volva is present as small, subconical white warts or felted patches in the center of the cap.
The gills are free, crowded, probably rather narrow, probably with a minutely flocculose edge, and white. Short gills are present.
The stem is relatively short, up to 40 mm long, moderately thick, white, without a ring, slightly fibrillose, with a narrowly clavate to subbulbous base. When dried, the base is 75% wider than the stem. Volval warts or patches are small, vague, white, felted subflocculose, and present on the lower quarter of the stem. In Bas' drawing, he shows the volva rather low on the stem.
The spores measure 11.2 - 13.3 (-13.8) × 9.4 - 10.8 (-11.3) µm and are inamyloid and subglobose to broadly ellipsoid, rarely ellipsoid, sometimes broadened subapically so that they appear egg-shaped. Clamps are absent at bases of basidia.
It was originally described by Karsten in Russian Lapland. Earlier Karsten had found what he believed was the same species in the bank of the river Tuloma in Russian Lapland among grasses in the sandy bank of the Tuloma River.
In 1982, Bas stated that this species was known only from the type. Bas points out that this species has often been mistakenly placed in section Vaginatae however it appears to be more closely related to A. friabilis (Karst.) Bas and A. farinosa Schwein.—R. E. Tulloss and L. Possiel
≡Amanita vaginata f. hyperborea (P. Karst.) Veselý. 1933. Ann. Mycol. 31(4): 280.
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.
The following text may make multiple use of each data field.
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 subdivision of
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 is derived from the protolog of the present taxon and (Bas 1982).
Bas (1982): Up to 60 mm wide, white at least over disc, convex to plano-convex, probably somewhat umbonate, somewhat shiny (exsiccatum), without distinct fibrillose pattern under hand lens (exsiccatum); context thin; margin rather strongly and densely sulcate (in exsiccatum 0.25-0.5R and ca. 12 grooves per cm); universal veil as small subconical warts (in exsiccatum 0.5 - 1 × 0.5 - 1.5 mm) to felted patches.
Bas (1982): free, crowded, white, probably rather narrow, probably with minutely flocculose white edge; lamellulae present. [Note: "lamellulae" is mis-spelled "lamellae" in the original; however, the context makes clear which word must have been meant.—ed.]
Bas (1982): up to 40 mm long, moderately thick (in exsiccatum 20 - 30 × 4 mm), white, slightly fibrillose; bulb as clavate stipe base or somewhat more pronounced (in exsiccatum 7 mm wide); context not described; exannulate; universal veil distributed on lower quarter of stipe as small vague warts or patches, white, felted-subflocculose.
Bas (1982): "difficult to analyze because of heavy moulding"; with thin gelatinized suprapellis; filamentous hyphae 2 - 6 μm wide, interwoven or subradial; clamps lacking.
Bas (1982): "impossible to analyze in both collections."
Bas (1982): 48 - 65 × 12.5 - 14.5 μm, rarely 2- or 3-, predominantly 4-sterigmate; clamps lacking.
Bas (1982): On pileus: elements yellowish in 10% NH4OH, with elements showing tendency to anticlinal (erect) orientation at least in bases of warts; filamentous hyphae 3 - 8 μm wide, abundant, often with somewhat refractive contents; inflated cells abundant, subglobose to ellipsoid to broadly ovoid, 20 - 65 × 15 -55 μm, terminal singly or in short chains; vascular hyphae scattered; clamps lacking. On stipe base: "breaking up into small, thick, felted, poorly delimited patches without...trace of...(sub)membranous outer layer"; colorless in 10% NH4OH with exception as noted; filamentous hyphae 3 - 7 μm wide, branching, thin-walled; inflated cells globose to ellipsoid to ovoid, 20 - 70 μm long, thin-walled, terminal singly; vascular hyphae scarce, yellowish (sometimes in 10% NH4OH); clamps lacking.
Bas (1982): "difficult to analyze"; [longitudinally] acrophysalidic; acrophysalides up to 25 μm wide; clamps lacking.
double click in markup mode to edit.
lamella edge tissue
Bas (1982): [30/2/2] 11.2 - 13.3 (-13.8) × 9.4 - 10.8 (-11.3) μm, (Q = 1.1 - 1.35; Q' = 1.2), hyaline, colorless, smooth (per figure), thin-walled, inamyloid, broadly ellipsoid to (rarely) ellipsoid; apiculus sublateral (per figure), proportionately medium to small, abarupt, cylindric (per figure); contents "sometimes...cloudy and somewhat refractive"; color in deposit not recorded.
Bas (1982): From grassy bank of river.
Bas (1982): RUSSIA: MURMANSK OBLAST - Murmansk, along Tuloma River, ca. Kola [ca. 68°52'31" N/ 33°05'02" E, ca. 80 m], 27.viii.1861 P. A. Karsten 1545 (holotype, H), 1544 (isotype, H).
Bas (1982): "In 1876 Karsten published a new species of Amanita under the name Agaricus (Amanita) hyperboreus from material collected by him in 1861 in Russian Lapland. The name Agaricus gemmatus var. lapponicus Karst. ('Enum. Fung. Lapp. p. 197') is given as a synonym, which seems somewhat strange as the date of publication of Karsten's "Enum. Fung. Lappl ...' is usually given as 1882. Fortunately Dr. H. Harmaja, Helsinki (in lit.) informed me that this publication of Krasten appeared as a preprint 16 years before it was published again in a journal in 1882 (see synonymy...), so that the name A. gemmatus var. lapponicus is 10 years older than the name A. hyperboreus.
"The only information on this var. lapponicus given by Karsten in 1866 is that it had a white cap and was found on a sandy bank of the river Tuloma. The description of the same taxon under the name A. hyperboreus in 1876 provides more information. From this we learn that the whole fruiting body is white, that the 6 cm wide pileus has a sulcate margin and is covered with angular warts., and that the 4 cm long stipe has a bulb and is exannulate. The spores are said to be globose and to measure 10-14 μm. Karsten mentions a resemblance with varieties of A. vaginatus but stresses the warts on the pileus and the habit of the fruit-body as differential characters. Later Karsten continues the use of the epithet 'hyperboreus' (e.g. in 1879: 40, in Amanitopsis).
"It is somewhat unexpected to find in the Karsten Herbarium in the Botanical Museum in Helsinki on collection (Karsten 1545) under the name Agaricus (Amanita) hyperboreus and another (Karsten 1544) under the name Amanitopsis gemmata, both collected on the same day and at the same locality (Russia, peninsula Kola, near Kola, among grasses on sand near the bank of the river Tuloma, 27 VII 1861)).
It seems very probable that Krsten 1545 and Karsten 1544 originally formed on ecollection which for unknown reasons has been split in two parts which got different herbarium numbers. This assumption is strengthened by the facts that on the packet of Karsten 1545 the original specific epithet of the name Agaricus gemmatus has been deleted and replaced by the epithet 'hyperboreus' (in Karsten's handwriting), and that the two collections certainly are conspecific. Therefore I consider Karsten 1544 to represent an isotype. This is of some importance as the specimen in that collection is in a somewhat better condition than the two in the holotype collection Karsten 1545. Particularly characters of the stem can be observed much better in the isotype."
"Amanita hyperborea has generally been considered a member of Amanita section Vaginatae and has been confused with A. nivalis Greville and other white or whitish taxa near A. vaginata (Veselý 1933: 280; Kallio and Kankainen 1964: 207; Kühner 1972: 34; Bas 1977: 86; Moser 1978: 221). Examination of the type, however, has shown that A. hyperborea is to be placed in section Amanita near A. friabilis (P. Karst.) Bas, and what is more, that the possibility that it is a white variety of that species can not be neglected.
It is the distinctly clavate subbulbous base of the stipe with indistinct, felted-flocculose perhaps sometimes slightly wart-like remnants of the volva that excludes A. hyperborea from section Vaginatae and, as the spores are inamyloid, refers it to section Amanita.
In that section the rather small fruit-body with exannulate stipe and wart-like volval remnants together with the more than 10 μm long, subglobose to ellipsoid spores make A. hyperborea belong to a group of species of which A. friabilis and A. brunneoconulus Bas & Gröger are until now the only European representatives. [Note: Subsequently, A. basiana was described as close to A. friabilis and A. hyperborea. Also the placement of A. brunneoconulus has become less clear.—ed.]
Except for the lack of pigment in A. hyperborea, there is very little that distinguishes this species from A. friabilis. In the latter the spores are on an average about 1 μm smaller, viz. 10 - 12.5 × 8 - 10 μm, but the length-width ratio of the spores of A. hyperborea falls well within the range fo that ratio in A. friabilis (1.1 - 1.5, averages per collection 1.2 - 1.35). The size of the basidia, the diameter and the arrangement of the hyphae in the pileipellis, and the size of the inflated cells in the volval remnants are about the same in the two taxa.
The structure of the volval warts on the pileus of the type material of A. hyperborea is rather difficult to analyze, but a careful comparison with that of the volval warts of A. friabilis has given me the impression that in the former the inflated cells form less frequently rows (and then short ones) than in A. friabilis where they are frequently found in rows of two to six. Moreover, the refractive contents of the probably somewhat more abundant hyphae in the volval remnants of A. hyperborea are practically lacking from the volval hyphae of A. friabilis which therefore are considerably less conspicuous. For these reasons I think that for the time being A. hyperborea and A. friabilis should be maintained as independent but closely related species, pending further information on the first of the two."
The following diagram provides a comparison of the sporographs of the present species and A. friabilis:
Especially since the spore measurements from the holotype and isotypes of the present species are from material collected more than 150 years ago and probably does not illustrated the full range of variation in size and, possibly, in shape; the comparison of sporographs suggests a greater difference in spore size-shape than was apparent in 1982. On the other hand, one must take into account that Bas rounded his Q values to the nearest 0.05 and his spores measurements to the nearest 0.5 μm, which will account for some differences in the sporographs. Also, the sample sizes supporting the two sporographs are rather different.
—R. E. Tulloss
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