Stinkhorns

About

Stinkhorns are members of the Phallaceae mushroom family and are easily recognizable by their unique shape and pungent smell [1]. Stinkhorns are characterized by their phallic appearances, hence the reference to the term Phallus in their taxonomic group name [4]. Some species will grow appendages that give them an octopus-like or lacey skirt appearance [1]. It is often stated that you will smell a stinkhorn before you actually identify them due to their odor which resembles rotting carrion or dung [4]. Stinkhorn stalks range in color from white, beige and olive to bright reds and oranges [1]. This species of fungus attracts numerous soil invertebrates, such as blowflies, beetles and slugs [4].

Habitat and Range

Stinkhorns grow naturally in North America and are most diverse in tropical or subtropical regions [3]. They grow particularly well in Florida and the Gulf Coast region of America, but it is relatively unknown which species of stinkhorn are native or introduced to the region, along with the rest of North America [4]. These fungi can become easily established in temperate regions such as Western New York after introduction [4]. Stinkhorns are often introduced via human activity, such as the transportation of soil, sod, trees and other organic materials that contain microscopic hyphae from other regions of the country [3]. Stinkhorn fungi can exist in any environment that provides organic matter as this is their food source [5]. They can appear in forests, gardens, lawns and even on bare soils [1]

Growth and Toxicology

Stinkhorns begin their life cycle as small egg-like structures that appear on the surface of the soil or mulch [4]. These eggs attach themselves to the fruiting substrate via rhizomorphs, which are delicate white strands of fungal tissue [4]. Within as little as a few minutes or hours, a stalk will emerge from the egg structure and stretch upwards [2]. The stinkhorn stalk is topped with a pungent, slimy spore mass known as the gleba [2]. The gleba attracts a series of invertebrates with its stinky odor that feed on the spore mass and then transport the spores elsewhere [4]. After the feeding invertebrate leaves the stinkhorn, its spores are spread through excrement or are transported by sticking to the invertebrate via the slime of the gleba until they stick elsewhere in the environment [4]. From here, the spores will establish a new crop of stinkhorn fungus if the environment is suitable, continuing their short-lived life cycle. While stinkhorns have a somewhat unsettling appearance and odor, they are not poisonous with a few exceptions [4]. In fact, many stinkhorns are edible in the egg state and are used for culinary purposes, however correct identification of the spores is essential to avoid potential calamity [4].

Ecosystem Function

Stinkhorns play an essential role in their ecosystems as they are decomposers, so they aid in the breakdown of organic litter that would otherwise sit on the soil surface and potentially stifle other species [4]. They are also an important food source for many soil invertebrates [4]. Interactions between stinkhorns and invertebrates are known to be beneficial, but are poorly studied so not much is known about their ecological role besides the basics.

References

1. P, V. and ian. (2016). Stinkhorns. https://hort.extension.wisc.edu/articles/stinkhorns/.

2. Phallaceae. (n.d.). . https://plantbiology.natsci.msu.edu/mushrooms/phallaceae/.

3. Phallaceae: The Stinkhorns (MushroomExpert.Com). (2011).</ref> https://www.mushroomexpert.com/phallaceae.html.

4. Phillips, E., J. L. Gillett-Kaufman, and M. E. Smith. 2018. Stinkhorn Mushrooms (Agaricomycetes: Phallales: Phallaceae). EDIS 2018.

5. Stinkhorns. (2005). http://hyg.ipm.illinois.edu/pastpest/200519b.html.