Botanical Articles by Lou_Jost
New Pleurothallid Orchids from the Cordillera del Condor of Ecuador :  Here I formally describe three new species of orchids that I discovered in the Cordillera del Condor. This article is published in Selbyana 25:11-16 (2004). See my Orchids of the Cordillera del Condor report for more details about the area.

Teagueia Explosion!: The story of the discovery of (at the time) TWENTY new species of the orchid genus Teagueia on three neighboring mountaintops in the Andes of east-central Ecuador. Prior to these discoveries, the genus Teagueia only had six members, three from Ecuador and three from Colombia. Remarkably, all twenty new species share floral and vegetative characters that are not found in the six previously known Teagueia species, suggesting that all twenty evolved locally from a recent common ancestor. This is the most dramatic species radiation yet known from Ecuador, exceeding even the famous Scalesia radiation on the Galapagos Islands. Later discoveries have made this radiation even more interesting; there are now THIRTY new species instead of twenty! For a more systematic discussion of the species of Teagueia, see Monograph of the Genus Teagueia Luer (Orchidaceae).

A version of this article first appeared in Pleurothallid News and Views, the newsletter of the Pleurothallid Alliance.A version has also appeared in the Orchid Digest 68:8-13 (2004).

Latest Orchid Discoveries : Here I post the latest new orchid species as I discover them. Recent discoveries include new species of Maxillaria, Ponthieva, Lepanthes, Teagueia, and Epidendrum.

Mystery Plants : Here I post Ecuadorian plants that I am having trouble identifying. I invite comments by experts, who may write me at the address on the home page.

An Analysis of the DNA-Based Reclassification of the Pleurothallid Orchids: Recently Pridgeon et al. proposed a controversial reclassification of the orchid subtribe Pleurothallidinae. The published responses to their proposal have either embraced it uncritically or rejected it completely. The truth is somewhere in the middle.This article looks at the details, and concludes that some of the proposed genera should be accepted, while others lack sufficient backing.
Lepanthes of Ecuador Identification Guide: This online book is meant to be used with Dr. C. A. Luer's Lepanthes monographs (published by the Missouri Botanical Garden). It arranges the Lepanthes of Ecuador into many small more-or-less natural groups, and provides a key to those groups. For each group, all known Ecuadorian species are illustrated and presented in two side-by-side scrollable frames to facilitate comparison. Dr. Luer's illustrations (used here with his kind permission) are supplemented by photos when available, and by my own drawings of new unpublished species. NOT READY YET!! THIS IS LOTS OF WORK!!!!!
Biogeography of the Pastaza Watershed (Eastern Andes of Central Ecuador): This online book treats the amazingly rich and highly endemic flora of the Pastaza watershed and surrounding area. More plant species are endemic to this small valley than to all of the Galapagos Islands. This book concentrates on orchids, and includes species accounts for some of the ninety orchid species endemic to the watershed. It also includes species accounts for some of the many other plants endemic to the watershed. Some nonflowering plants are also treated, including the endemic monotypic liverwort genus Myriocolea, discovered on the Rio Topo in 1857 and only just now rediscovered by S. R. Gradstein, Noelle Noske, and myself. The distributions of the orchids of the area shed light on the nature of plant evolution in the Andes, and contradict some popular theories.
Orchids of the Jocotoco Foundation Reserves: The Jocotoco Foundation was formed to buy and manage reserves for critically endangered Ecuadorian birds. The reserves coincidentally contain many threatened and endangered plant species, especially orchids. The Foundation has asked me to assess the conservation value of their reserves for orchids, and this article reports the ongoing results of those investigations.
Using Sympatry to Resolve Species-Level Problems in Lepanthes: 1. L. nummularia . Lepanthes nummularia needs to be split into between four and six species, based on the existence of multiple consistent sympatric forms.
Orchids of Latin America: A general, nontechnical introduction to the orchid world. First appeared in Latin American Travel Advisor.
On The Nature of Plant Endemism in the Eastern Andes: My studies of orchid distributions in the eastern Andes show that geographic isolation is not the driving force behind the evolution of range-restricted species. Species have restricted ranges not because they can't cross geographic barriers, but rather because they specialize in particular microclimates of limited extent.
Use of Sympatry to Resolve Species-Level Taxonomic Issues in the Genus Lepanthes (Orchidaceae): The herbarium record is very sparse in this genus. It can be hard to guess, from the limited material available, whether two forms belong to the same or different species. My study of the Lepanthes of the Pastaza watershed show that certain forms which had been lumped into a single variable species are in fact sympatric here without interbreeding. Such forms must be split into separate species. Among the species which need to be split are Lepanthes muscula, L. biloba, L. mucronata, and perhaps L. nummularia. On the other hand, sympatry relations confirm that the following confusing species pairs are indeed distinct: L. transparens/contingens, L. decurva/caudatisepala, L. homotaxis/clandestina.

Discovery of a New Genus: This article contains my observations on the active trap mechanism of the lip of what was then called Masdevallia teaguei. On the basis of these observations Dr. Luer established a new genus, Jostia, for this plant. However, recent DNA evidence shows that this species still deserves to be kept in Masdevallia......

This article first appeared in the Pleurothallid News and Views, the newsletter of the Pleurothallid Alliance.

Monograph of the Genus Teagueia Luer (Orchidaceae): When Dr. C. A. Luer published the first monograph of the genus Teagueia, there were only six known species. Over the last few years my students and I have discovered about thirty new species in my study area, and more are on the way as I figure out how to reach additional unexplored mountain peaks here. This online book is the ideal way to keep the world posted on this remarkable explosion of Teagueia species, since it can be updated so easily. See also Teagueia Explosion! for the story of their discovery.

A Simple Point-centered Quarter Method for Non-Uniform Forests: The Point-centered Quarter method (PCQ) has long been a standard technique for measuring plant density. Unfortunately the botanists who invented it were poor mathematicians, and they made assumptions which cause the standard density formula to be grossly invalid in nonuniform forests. Recent critics have recognized this problem and have recommended that the method be abandoned in spite of its other advantages. However, I have derived a new formula for PCQ data which is valid for nonuniform forests. I have tested the new formula both in computer-simulated and real forests and find it to be accurate. Therefore there is no need to abandon the PCQ method. The new formula uses exactly the same variables as the classical formula, so it can be used to reanalyze old data and find the correct density.

Orchids of the Cordillera del Condor: The Cordillera del Condor is an isolated range of mountains just east of the main body of the Andes, along the frontier between Ecuador and Peru. It is very poorly known, because until recently it was the site of border conflicts between those two countries. In addition, the resident Shuar indigenous people are somewhat hostile towards outsiders. The Missouri Botanical Gardens Cordillera del Condor Project is now working to explore the region under the direction of David Neill, Director of the Herbario Nacional del Ecuador. I was able to go on two of his expeditions, one to the white sand mountains above Tinkimints, and another to the high peaks (2700 m) above Warints. This web page describes the orchid specimens found on these trips, including several new species.
I want to express my sincerest gratitude to Dr. Carl Luer for his help and guidance in my orchid studies. Special thanks to John and Ruth Moore for their generous financial support since the beginning via donations to the Population Biology Foundation, and to the San Diego County Orchid Society for their continuing support. Thanks also to the Orchid Resource Center, the Center for International Studies-Andean Study Programs, Kent and Cherise Udell, and R. Bozek and Alyssa Roberts. The discoveries reported here are theirs as well as mine.