Aylostera pygmaea was one of the first of the Mediolobivias to be described, in 1905; the name refers to it being smaller in stature and spination than other previously described similar plants.
Like A steinmannii this is a species covering a wide geographical area and a multitude of variations, many of which have at some time been described as species. The numbers of species, subspecies or varieties there are depend on whether you tend towards lumping these together or splitting them apart and there is an element of subjectivity. Mosti & Papini (2011) have taken the view that discrete populations with differing constant characteristics and which do not overlap in range, and for which no hybrids have been found, have a legitimate claim to being named differently: given specific status, even if the concept of “species” does not really fit very well with these plants. At the opposite extreme there are publications lumping together all Mediolobivias with a similar shaped body as “A. pygmaea“, including A. colorea, A. diersiana, A. eos, A. haagei, A. orurensis, and a host of others treated as good species by Mosti & Papini and on this website.
The system I adopt here at the collection is that all plants retain the label they originally arrive with; in many cases this is “A. pygmaea“. In some cases nurseries give the name “A. pygmaea” as a catch-all, as if to say “a pygmaea type of plant”, and in some cases, Aylostera sp. with just a field number. Over time and through research some of these get reassigned here to one of the “split” species and given a new label. All original information is always retained, even where it is clearly wrong, and everything is also recorded electronically. The species listed below are all currently named and labelled A. pygmaea; some of these are destined to move to a different place on the bench in due course.
The description is here.
Plants labelled A. pygmaea in the collection include: