Sporocarps scattered, stipitate, depressed globose, only slightly
umbilicate below, apically deeply umbilicate (sic!), total height
up to ca. 1.5 mm, head diam. up to ca 0.5 mm.
Dark brown, discoid under individual sporocarps, confluent under
± cylindric, slightly furrowed, dull orange, dark as hypotallus
towards base, length ca. 2/3 of total height.
Smooth, dull yellowish green on sides of head, bright ochraceous on
top and into umbilicus in RL, basically with a brownish circular area
around stalk; pale yellowish to almost hyaline in TL, towads apex
bright yellow in TL, (yelleow pigment seems to be somewhat water
soluble), apparently almost limeless laterally, apically with fine
(< 1 µm Ø), bright yellow granular matter.
Columella not seen; at most with a somwhat thickened base.
Capillitium of hyaline tubules, 1- ca. 6 µm broad, branched whith
expanded nodes into a lax net, no lime inclusions observed.
Spores globose, medium brown in RL, pale greyish brown in TL,
with fine, ± regularly distributed warts, slight tendency to
coalesce to very short lines, 8-9-11 µm Ø (n=25).
Phaneroplasmodium, dull greyish yellow.
Cultured in moist chamber. Material, twings of Cistus sp., collected
primo feb. 2014 by Thomas Læssøe in Cyprus. MC prepared on 7.3.2014,
active plasmodia detected 18.3.2004 and mature sporocarps harvested
The identification of this collection gave me some problems, so I
called for suggestions on this page. Initially I focused on the apical
umbilicus as a diagnostic character. That eventually turned out to be
Hans van Hooff (the Netherlands) gave the solution. He reported
similar fructifications in moist chamber culture on bark of Juniperus,
and added a photograph which clearly shows the same taxon. Hans
identified his specimen as Physarum flavicomum berk.
I have afterwards done a more careful check of the literature and
found that Gray (1961)
reported the variation in P. flavicomum sporocarps in culture depending
upon moisture conditions in the chambers. High humidity
resulting in less lime in the peridium and somewhat distorted
sporocarps, including umbilicate ones.
Abbreviations: TL : transmitted light; RL : reflected light; Ø : diameter;
TBU : Danish Botanical Topographical District.
Colour-codes refer to: Kornerup, A. & J. H. Wanscher 1974: Farver i farver.
5th reprint. Politikens Forlag, Copenhagen.
When not otherwise indicated spore measurements are given as:
min-mean-max or (extreme-)min-mean-max(-extreme). Spore measurements are exclusive of ornamentation.
Line drawings are free hand sketches.
Distribution maps: Maps of Danish distributions are based on material seen
by the author. World distributions are based on
reports extracted from literature.