Stemonitis splendens
🏷️ Description
Nature is full of bizarre and beautiful organisms, and one of the most intriguing among them is the Chocolate Tube Slime Mold (Stemonitis splendens). If you've ever stumbled upon what looked like tiny, brown hairs or miniature chocolate sticks growing on decaying wood, you might have just found this incredible slime mold!
Chocolate Tube Slime Mold is a species of slime mold found worldwide, commonly appearing on fallen logs and decaying wood. It thrives in humid environments and can occasionally pop up on damp wooden structures, such as decks or indoor wood in moisture-rich areas.
Despite its mold-like name, it’s not a fungus! Slime molds belong to an entirely different kingdom of life called Amoebozoa, meaning they behave more like amoebas at certain stages of their life cycle.
🧐 How to Identify It
This slime mold is easy to recognize, thanks to its distinctive sporangia (fruiting bodies) that resemble chocolate tubes or tiny brown hairs:
🔹 Sporangia: Dark purplish-brown, dry, smooth, and standing 10–20 mm tall and 1–2 mm wide.
🔹 Stalks: Slender and black, about 3–5 mm long.
🔹 Spores: Tiny (6–9 μm in diameter), brown, round, and wart-covered. These are released into the air when disturbed.
🌍 Where Does It Grow?
Chocolate Tube Slime Mold is quite common within its range and has been observed across all Australian states, as well as in many other parts of the world. It prefers sheltered, moist environments, growing in clusters on decaying wood—from fallen logs in forests to rotting wood in yards and even damp indoor areas.
Some people have even found it growing in unusual places, like on wooden decks where the paint has chipped away, revealing damp wood underneath.
🔄 Life Cycle
Like all slime molds, Chocolate Tube Slime Mold has a fascinating life cycle:
1️⃣ Plasmodium Stage: It begins as a white, slimy mass, resembling tiny amphibian eggs. At this stage, it moves like an amoeba, creeping along in search of a good place to settle.
2️⃣ Sporangia Formation: Once it finds a suitable location, it stops moving and forms its characteristic tube-like sporangia, where spores develop.
3️⃣ Spore Dispersal: When disturbed (even by a touch), it releases clouds of brown spores into the air. These spores then spread to new habitats, where they “germinate” after heavy rainfall, restarting the cycle.
🤔 Is It Dangerous?
Good news! Chocolate Tube Slime Mold is completely harmless to humans, pets, and living plants. It only feeds on decaying organic matter and does not infect wood like true molds do.
Many pet owners worry when they see their dog sniffing around it, especially after the sporangia release a puff of spores upon touch. However, there is no known toxicity to animals or people. If you want to remove it, simply wash it away with water.
One person even reported finding it after a tropical storm, growing on their deck where moisture had settled. Upon trying to scrape it off, it released a cloud of brown spores—a classic slime mold reaction! But rest assured, it’s just part of nature’s fascinating cycle.
📜 Synonyms
Stemonitis morganii Peck (1880)
Stemonitis baeuerlinii f. fenestrata Rex (1890)
Stemonitis webberi Rex (1891)
Clathroidastrum splendens (Rostafinski) Kuntze (1891)
Clathroidastrum morganii (Peck) Kuntze (1891)
Stemonitis baeuerlinii Massee (1892)
Stemonitis acuminata Massee (1892)
Stemonitis splendens var. webberi (Rex) Lister (1894)
Stemonitis fenestrata (Rex) T. Macbride (1899)
Stemonitis splendens var. fenestrata (Rex) Torrend (1908)
Stemonitis splendens var. morganii (Peck) Torrend (1908)
Photo sources:
Photo 1 - Author: Damien Wallace (CC BY 4.0)
Photo 2 - Author: Scott Warner (CC BY 4.0)
Photo 3 - Author: Karen Guin (CC BY 4.0)
Photo 4 - Author: Julie Travaglini (CC BY 4.0)
