Singer’s Marasmius sect Sicci subsect Siccini ser Haematocephali (as it’s referred to in Flora Neotropica 17) has a strict definition which does not only take cap color into account. The nesting of that series within a given subsection, and the nesting of that subsection within a section, means that the series inherits the sum total of all its parent ranking’s requisite features; features I am not an expert on, and neither are you. That doesn’t mater.
Why doesn’t it matter?
Because not a single wine-red Marasmius observation on the entire site shows evidence of the scrutiny and study and literature comparison necessary to make fine grain species determinations between and among macroscopically similar species other than my observations from Madagascar, which were part of Jackie Shay’s SFSU master’s thesis, overseen by Dr. Desjardin:
Those two wine-red and one pale colored marasmii turned out to be the true M. haematocephalus; an identification supported by DNA and comprehensive microscopy. If instead of arriving at that neat and clean ID, it was Jackie and Dr. Desjardin’s conclusion that the Malagasy haematocephaloid(s) we collected were undescribed members of M. subsect. Haematocephali, and they chose not to describe them at that time, it would be acceptable to label them as such here. It is not acceptable to do so solely on the basis of color, which is exactly how that name has, historically, been applied on this site, and how you are advocating for its use right now.
TLDR: You can’t argue for the validity of M. subsect. Haematocephali on the basis of features which are practically never documented or taken into consideration on the “haematocephaloids” that show up on MO. You also can’t have M. subsect. Haematocepahli be shorthand for “things that look like Marasmius haematocephalus” and simultaneously be a grouping strictly defined by microscopic characters, because those are two completely different things.
Since when does Marasmius subsect. Haematocephali have to be red? Shouldn’t sections be based on phylogeny? Sometimes cap color is a characteristic with taxonomic value and sometimes it’s highly variable within a section.
Just because there are other red Marasmius that look like M. haematocephala does not mean that this is not a good section. The species that are phylogenetically close to M. haematocephala will remain in this section, and similar looking species which are in other sections of Marasmius will be in their respective sections.
You’re being reiterative. Searchability is maintained by having a deprecated name remain usable and applicable to observations. Deprecating it ensures that it is not mistaken for being a current taxonomic concept. Say something new or leave this name alone.
note: it bears mentioning that you have applied this name to an observation which does not meet the subsection’s primary criterion — being red.
This name should be approved because it refers to the Marasmius species that resemble M. haematocephala. If someone decides to study this polyphyletic group, it would be useful for them to be able to search for this name instead of having to sort through thousands of Marasmius species which do not have thin wiry stems, broadly spaced gills and colorful caps.
from a systematics standpoint. That is not this name. Blunt insistence to the contrary on your part affects this 0%. Try making a reasoned argument instead.
To make Marasmius haematocephalus group the preferred synonym for this name?
Remains useful, and therefore should not be deprecated
this represents an excellent example of a name which should still be in use for its utility in sorting and identifying, but should remain deprecated for having been left behind as an accurate taxonomic concept years ago. MO’s names in un-bolded italics have been universally regarded this way for years. i see no good reason to change that.
re: “Unless this subsection has been lumped into a different subsection by a taxonomist”
a species or group of species does not need formal reassignment from one umbrella to another to be considered obsolete. we know that the wine red marasmii are not related to each other on the basis of gross appearance, thanks to Jadson’s work in this area. those species are almost certainly not going to all fall under any other heading, together, ever again. they will end up sorted on the basis of whatever combination of physical and molecular features dictate the evolving future of Marasmius s.s. classification.
Useful for identification even though it is not a monophyletic clade
It should stay approved. Its utility for MO identification has nothing to do with its validity as a taxon.
showed on this:
and a following slide (not shown to protect unpublished data) how many similar-looking, blood-headed Marasmius spp. can be quite distantly related to one another. color, unsurprisingly, is therefore an unreliable character to be grouping our blood-headed Marasmius observations without microscopy.
Created: 2011-12-12 12:57:28 CST (-0600) by Danny Newman (myxomop)
Last modified: 2018-03-03 22:06:49 CST (-0600) by Alan Rockefeller (Alan Rockefeller)
Viewed: 347 times, last viewed: 2019-01-15 15:51:27 CST (-0600)