Sphaerobolus stellatus

Scientific name:  Sphaerobolus stellatus (Tode) Persoon
Derivation of name: Stell- means "star."  
Synonyms:  
Common name(s):  Cannon fungus; Sphere thrower;
Artillery fungus; Shotgun fungus.
Phylum:   Basidiomycota
Order:   Phallales
Family:   Geastraceae
Occurrence on wood substrate:  Saprobic; solitary or
grouped on decaying wood (e.g. landscape bark mulch),
sawdust, herbaceous debris, or dung; spring through fall.  
Dimensions: The fruit bodies are 1-3 mm wide.    
Sterile nest surfaces: Yellow-orange, becoming whitish.
The nest opens by splitting into 4-9 starlike rays.
Fertile inner tissue: Single peridiole ("egg") about 1 mm
in diameter; dull yellow.
to reddish-brown to dark brown."
Edibility: Are you kidding? Arora states that "Several
hundred would be needed for a mouthful!"
Comments: The peridioles are sticky and will glue
themselves to objects such as house siding, windows, and
cars. Shredded hardwood (tanbark) seems most prone
to supporting this fungus. To avoid the next-to-impossible-
to-get-off little tarry black dots, use mulches in areas next
to houses and cars that do not support the growth of this
fungus. Recommended types are pine bark mulch or cedar
or cypress mulch. Recent studies (Geml, J., et al., 2005)
indicate that three species of Sphaerobolus are in the
Northeast, one of which, Sphaerobolus ingoldii, was
determined to be new. The diameter of its peridioles is
about 1 mm. The other two species, S.stellatus and S.
iowensis, have peridioles about 1.5 mm in diameter but can
otherwise only be differentiated from each other using
micromorphological features. As a result, many specimens
identified as S. stellatus are likely to be S. iowensis and
vice versa.

More information at TomVolkFungi.net:  

Figure 1. Do you see the penny lying on the landscape
mulch?


Figure 2.  Now that you see the penny, do you see the
fungus? There are three specimens in the foreground. This
fungus is tiny!

Figure 3. Note the star-shaped peridium and the single egg
(peridiole) within.

Figure 4. Here is the same specimen as in Figure 3. The
inner layers have turned inside out, leaving behind a whitish
ball on top of the rays. The peridiole was shot away.


Figure 5. The peridium is just beginning to split apart in the
specimen on the far right, exposing the single peridiole.
Photo © John Dawson.

Figure 6. Several stages of development are in view here.
The brown, shiny sphere to the lower left is a peridiole that
for whatever reason, did not make it very far. These "eggs"
are capable of being propelled up to 6 m.