A Thing of Beauty

This is the sec­ond post for this year's Week of the Fungi on STC, a spo­radic un­der­tak­ing. This an­nual fes­ti­val is our way to hail the start of the fall mush­room col­lect­ing sea­son in parts of our home ter­ri­tory (the north­ern hemi­sphere).

by Elio

A thing of beauty is a joy for ever:
Its love­li­ness in­creases; it will never
Pass into noth­ing­ness…
—from Endymion, by John Keats (1878)

We can at­test to these truths through a lone piece of am­ber. Be­tween 50 and 35 mil­lion years ago, a spring­tail (Collem­bola) got stuck in some resin, prob­a­bly from a conifer. Be­fore it could free it­self, more resin dripped on it, even­tu­ally en­tomb­ing it com­pletely. In time, the resin be­came am­ber, but be­fore that hap­pened, a fun­gus grew on the insect's ca­daver, sprout­ing nu­mer­ous spore-bear­ing struc­tures (coni­d­io­phores). For­tu­nately, this piece of am­ber found its way to two paleomy­cologists, Hein­rich Dör­felt and Alexan­der Schmidt, who read­ily iden­ti­fied the fun­gus as a mem­ber of the genus As­pergillus.

Fig­ure 1. The en­tombed spring­tail with nu­mer­ous co­ni­diophores. Source

Fig­ure 2. Close-up of the coni­d­io­phores. Bar = 50 μm. Source

Fig­ure 3. A sin­gle coni­d­io­phore show­ing the ra­dial chains of spores typ­i­cal of As­pergillus. Bar = 50 μm. Source

Am­ber has served up other fas­ci­nat­ing glimpses of an­cient fungi, in­clud­ing the old­est known fos­sil mush­room en­trapped 100 mil­lion years ago. How­ever, the preser­vation of these coni­d­io­phores is stun­ning, prob­a­bly un­matched by any other piece of am­ber con­tain­ing fun­gal ma­te­r­ial. The likely rea­son is that the fun­gus did in­deed sprout these struc­tures af­ter the insect's bur­ial in the thick-but-still-liq­uid resin. Oth­er­wise, lit­tle would have been pre­served of its nat­ural shape.

An es­pe­cially il­lu­mi­nat­ing ar­ti­cle on the same sub­ject by Cor­nell stu­dent Chris­tine Lay­ton ap­peared in the famed Cor­nell Mush­room Blog.