Observation 326440: Amanita stirps Sororcula

Collector’s_Name: Alden Dirks
Substrate: Ground
Habitat: Hemlock forest
Host: Hemlock
Other: Description of the (more) mature mushroom of the pair found:
Cap: 8 cm in diameter, slightly depressed in the center, with geometric warts that are bluish grey on the outside and more whitish in their center, cap overall dry and smooth and shiny; prominent striate margin, about 1.5 cm wide
Gills: about 13 gills per cm, free from the stem, maybe the faintest bluish or greyish hue to them
Stem: 13 cm long, somewhat clavate, tapering at the apex, 8 mm by the cap and 1.2 cm by the base, no ring, powdery coating that can be rubbed off, small zigzaggy brown or grey markings (even more prominent on smaller specimen), dry and shiny
Base: remnants of a volva, dark grey-blue in color
General: overall darker, grayer, bluer, and more striking than other Amanita vaginata specimens I’ve seen

Species Lists


Proposed Names

28% (1)
Recognized by sight
55% (1)
Recognized by sight

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= Observer’s choice
= Current consensus


Add Comment
Sorry that you didn’t get an answer to your question.
By: R. E. Tulloss (ret)
2018-09-18 17:14:02 CDT (-0500)

When someone is proposing a species name then the ID is an ID in the ordinary sense.

When some gives some other sort of information, you can consider that someone is offering an approximation. In taxonomy at the subgenus level, the word stirps (simply is the Latin for “group”). The plural is “stirpes.”

It does not get an authorial citation.

A number of authors have use “stirps” as the lowest level above species in the genus Amanita. Most prominent in this usage (in my experience) was Dr. Bas in his organization of section Lepidella “from the bottom up.” Singer also used the term in a similar fashion (for example “stirps Brunnescens” in Amanita series Mappae).

There is no type to a stirps, but there is a characteristic species behind the name. To make the name of a stirps, Singer and Bas simply capitalized the name of the “characteristic species.” I follow their example.

I am responsible for provisional subdivisions of sections on the WAO website. It helps me communicate with people concerning imprecise attempts at identification from pictures (especially when so many taxa are not yet described) …such as happens on MO, where people are operating with pictures for the most part.

Very best,


Because the species are very difficult to distinguish from photographs,…
By: R. E. Tulloss (ret)
2018-08-11 16:43:23 CDT (-0500)

…people use Amanita stirps Socorocula to indicate that the species is one of those included by me in the cited stirps here:


The word “stirps” simply means “group” in Latin and people like Singer and Bas used it before me to indicate an informal grouping that can be useful in assembling a larger group such as a subsection or a series, etc.

Stirpes do not have authors and are not a recognized rank in the ICN. So to reference one you need to say something about where it comes from such as “stirps Ravenelii of Bas (1969).”

Very best,


Hi Rod
By: Alden Dirks (aldendirks)
2018-08-09 11:56:16 CDT (-0500)

Thanks. Could you please explain what this determination means? Is it the species (Amanita sororcula) or is the format Amanita stirps Sororcula referring to some other taxonomic division? On the internet it says stirps is a branch of a family, but here the division is much smaller than that, smaller than subgenus and section.

Thanks for the field notes.
By: R. E. Tulloss (ret)
2018-08-09 09:18:07 CDT (-0500)

Very best,