Mosses and liverworts, collectively known as “bryophytes”, were the first plants to emerge from the oceans onto dry land, about 300 million years ago. Many of them are still closely tied to water. Some of the most interesting bryophytes are riverside specialists adapted to regular submergence. Most bryophyte species have very wide geographic distributions, even ranging across multiple continents, since their spores are small and easily blown in the wind. Most scientists would not expect much local endemism in such a group. However, as we have also seen in orchids (whose seeds are small and spore-like), habitat specialization can lead to local endemism even in the absence of dispersal limitations or barriers. So it always pays off to look closely at places that combine unique geological and ecological factors.
The great Scottish botanist Richard Spruce was the first bryologist to look closely at the mosses and liverworts in our upper Rio Pastaza watershed, on his epic twelve-year trip from the mouth of the Amazon to the Pacific Ocean.He lived in Banos for six months, discovering many new species of mosses, liverworts, ferns, and flowering plants. Before he reached Banos from the Amazon basin, he had to cross our Rio Zunac, and then the nearby Rio Topo. As often happens, though, hard rains made it difficult to cross the Rio Zunac. He and his group of indigenous helpers managed to make the crossing, but were then trapped between the Zunac and Topo rivers as both rose to dangerous levels. They were stuck there for three days, and nearly starved to death (they ate toads to stay alive). But a botanist is never bored in a new country. While he was stuck between these two rivers he discovered the strangest bryophyte of his whole Amazon-to-Pacific expedition, a riverside liverwort which he named Myriocolea irrorata. He wrote in his journal (later published as Notes of a Botanist on the Amazon and Andes, edited by the co-discoverer of the theory of evolution by natural selection, Alfred Russel Wallace) that it was “perhaps the most interesting bryophyte that I have ever found.”
No one ever saw this plant again in life until Dr Rob Gradstein, then of the University of Gottingen, and his student Noelle Noske came to Banos in 2002 to search for it. They asked me to join them. Rob, Noelle, and I tried to follow Spruce’s journal. We failed to find the plant on the first day, but during our second day of searching we found lots of plants on the Rio Topo. We were tremendously excited, especially Rob! However the rediscovery was followed shortly by the news that the Rio Topo would be the site of a small hydroelectric project, which the local people opposed. Myriocolea irrorata, which was classified by the IUCN as Critically Endangered, became the emblematic species of the struggle to stop the project, but the government eventually forced it through. [Phylogenetic studies recently showed that the very unusual morphology of Myriocolea irrorata was a recently-evolved feature, and that it was actually part of the large genus Colura. Recently a new population of this species was found on the Cordillera del Condor in southeast Ecuador, far from the original population.]
Rob and I worked to have a bust of Richard Spruce erected here, and this became a reality in 2006, with the help of the Linnaean Society of London, Missouri Botanical Garden, the Birtish Embassy, Ghillean Prance, Raymond Stotler and Barbara Crandall-Stotler, and others. It was made by a local Banos artist, Edguin Barrera. Probably the only monument to a bryologist in all of South America!
On Rob’s visit to Banos in 2008, I took him to our Rio Anzu Reserve, to see if Myriocolea irrorata grew in the Rio Anzu. This is a limestone river with many interesting limestone-specialist plants. It was on these limestone cliffs that I had once found a new genus of orchid, which Gerardo Salazar and I named Quechua. On this trip Rob and I did not find any Myriocolea irrorata, but Rob did find another strange liverwort, in the genus Fossombronia, that he could not identify. Some Fossombronia (such as F. texana, found along the limestone streams of the Hill Country of central Texas) are limestone specialists (B. Crandall-Stotler, pers. com.), and this appears to be another. He collected it and began to work on its taxonomic placement. A few weeks ago, nine years later, he and his colleague Barbara Crandall-Stotler were finally confident that it was in fact a new species, still known only from the Rio Anzu. I was flattered to hear that they wanted to name it after me…
Last week, excited by this news, I went to the Rio Anzu to photograph “my” liverwort. The trip started out badly. A huge storm (said to have been a 50-year storm) had hit the area in December, washing out the aquatic park of the nearby city of Shell, and causing much flood damage. As I went up the entrance road to the Rio Anzu, , where once little forest streams quietly flowed, I saw deep bare newly-scoured canyons filled with fallen tree trunks. The road itself eventually became impassable due to the flood damage, and I had to walk a long way to the trailhead. Inside the forest the damage continued, with big washouts and landslides. This did not bode well for the riverside vegetation I had come to see. Nevertheless there were beautiful flowers growing in the forest; I was briefly distracted by Heliconia aemygdiana and a species of Eucharis, a relative of the amaryllis.
When I got to the rocky riverside where Rob had discovered the new Fossombronia, my worst fears were confirmed. There was almost nothing left of the thick moss layer that used to cover every surface. Most of the rocks looked and felt like they had been sandblasted, with fresh bare surfaces, no organic material at all. The ladyslipper orchids (Phragmipedium pearcei) that were one of the highlights of this vegetation had been severely damaged, though many tattered plants still clung to the downstream sides of the rocks, held by their white newly-exposed roots.
Before the flood:
After the flood:
Before the flood:
After the flood:
Some of the slightly sheltered pockets in the bare rocks still had traces of green moss. I desperately searched these for “my” Fossombronia. In nearly the same place as Rob’s initial discovery in 2008, I found what was left of them. It looked like the river stripped off all their leaves, but the bases of the plants were still alive and were vigorously resprouting! I shouldn’t have worried about them. This is, after all, the rough habitat they had evolved in for millions of years.