It is not easy to decide how to group these
highly variable plants into discrete species. It helps to think
carefully about the definition of a species. A species can be
thought of as the largest possible group of individuals who
freely exchange genes with each other. Two populations that
live together yet rarely or never exchange genes with each other
are seperate species biologically, no matter how similar they
might seem to us. See What
is a Species? in my Teagueia
Many of the new Teagueia species are clearly
distinct, and I do not feel uncertain about their status. I
am confident about the status of the following species: T.
alyssana, T. amplectans, T. ciliata, T. cymbisepala, T. dactylina,
T. deflexa, T. gracilis, T. magnifica, T. negristellata,
T. pailinii, T. scorpioidea, and T. shepardii.
Each of these is morphologically distinctive, without intermediates
connecting them to other forms, and without significant structural
variability. These species are not discussed further in this
section on taxonomic problems.
The following species show quite a lot of variability and may
actually contain two or more species: T. angustipetala,
T. cherisei, T. hemispherica, T. jostii, and T. protuberans.
Some of these show significant variation from one mountain to
the next (T. hemispherica, T. jostii) but show little
variation within a population. The others show quite a lot of
variation even on the same mountain.
The following sympatric species pairs are very similar: T.
aliana / pseudoaliana, T. grossilabia / angustipetala, and
T. aurata / grossmanii. Since T. aliana and T
pseudoaliana grow intermixed in the same areas, yet maintain
consistent differences, I conclude that they are not freely
exchanging genes and are good species, even though they are
very similar to each other. The situations of the other two
species pairs are not as clear and require more study.
The following species groups grow on different mountains and
so their differences might be explainable as geographic variations:
T. micrantha / protuberans / gracilis, and T. sancheziae
The following species pair clearly hybridizes and has many intermediate
forms, yet the extreme forms are very different from each other:
T. barbigera / aurata. In this case it will perhaps
be best to recognize the whole group as a single hybrid swarm.
the following weeks I will elaborate on these issues for each