Researching a recent post that included what I considered to be a Lycogala epidendrum slime mould, I came across a number of references to L. terrestre and began to rethink my previous identifications of L. epidendrum.

These Lycogala aethalia that we found in April 2023 at Strumpshaw Fen — according to myxomycetologist Bruce Ing — should be L. terrestre ? assuming that the immature aethalia is going to be very similar in colour to the plasmodium.

Bruce’s classic work — Myxomycetes of Britain and Ireland: An Identification Handbook (1999) — states that the plasmodium of L. epidendrum is “pure red or carmine, without orange tints” and that the plasmodium of L. terrestre is “orange, peach, pink or vermillion, rarely cream, without red tints”.

And then at Danish Myxomycetes, their key to identifying Lycogala suggests that the mature aethalia of L. terrestre is pale greyish brown and for L. epidendrum, dark greyish brown.

I’d say that the Lycogala that we found at Strumpshaw in April 2023 eventually had mature aethalia that were dark rather than pale.

Although, nearly two weeks later with many of the aethalia having opened to release their spores, the aethalia had turned a buff colour.

Anyway, the Danish Mxyomycetes entry for L. epidendrum states that L. epidendrum is a “very variable species” and as a result Bruce “reintroduced the . . .  name L. terrestre . . .  for forms with pale greyish brown aethalia and pink plasmodium”. They then state that “this segregation seems not to have found general acceptance”. [1]

In Fifteen new species from the myxomycete genus Lycogala by Leontyeva, Ishchenkoc and Schnittler (24 May 2023), they state in their abstract that they “propose to retain the name L. epidendrum for the globally most abundant species” and that they “do not recognize the species L. terrestre“. [2]

And then I stumbled upon an undated entry at the North East Fungus Study Group website stating that Carlos Lado at CSIC had classified L. epidendrum and L. terrestre as a single species — L. epidendrum. [3]

At nomen.eumycetozoa.com in an entry last updated 9th April 2024, it states that L. terrestre is a synonym of L. epidendrum. [4]

Here’s a video I came across where Dmytro Leontyeva discusses Lycogala epidendrum.

[1] www.myx.dk/spp/lycepi.html

[2] www.tandfonline.com/doi/full/10.1080/00275514.2023.2199109

[3] nefsg.co.uk/lycogala-epidendrum-sensu-lato

[4] eumycetozoa.com/data/report.php?busca=lycogala&por=gensi&id=138&tipo=Btax