Torulopsis or Cryptococcus?

Summary

Use of the generic name Cryptococcus Kützing should be avoided in yeast taxonomy, as it is both a „nomen dubium” and a „nomen confusum”. „Dubium” because it is at the least doubtful that the first Cryptococcus species described by Kützing (Cr. mollis) was a yeast (Kützing himself classified Cryptococcus among the Algae). „Confusum“ because it has appeared from an examination of authentic herbarium material of Cr. mollis, that Kützing dit not deal with one, bur with a mixture of at least five organisms.

The generic name Torulopsis Berlese, on the contrary, is a valid name for a group of asporogenous yeasts, since Berlese has purposely included, as appears from the diagnosis given, in his new genus Torulopsis the yeasts at that time brought to the genus Torula sensu Pasteur-Hansen.

The objection which at first sight could be raised against the acceptance of the genus Torulopsis, namely that the first species described by Berlese: Torulopsis rosea, belongs to the present genus Rhodotorula Harrison is untenable, since this species certainly was not a yeast with a carotinoid pigment. All evidence available is in favour of the suggestion that Berlese's species was identical with Torulopsis pulcherrima (Lindner) Sacc.

Herewith the validity of the generic name Torulopsis for the asporogenous, nonmycelium forming, colourless yeasts may be considered to be proved.

A slightly amended diagnosis of the genus Torulopsis Berlese is given.