New species of the genus Metschnikowia isolated from flowers in Indonesia, Metschnikowia cibodasensis sp. nov

Phylogenies in yeast species descriptions: in defense of neighbor-joining

The neighbor-joining (NJ) method of tree inference is examined, with special attention to its use in yeast species descriptions. How the often-vilified method works is often misunderstood. More importantly, given the right kind of data, its output is a phylogram that illustrates a hypothetical phylogeny that is just as credible as that obtained by any other method. And as with any other method, the result is greatly affected by sampling intensity, particularly the number of aligned positions used for analysis. I address various allegations, including the claim that the method is phenetic, and therefore not phylogenetic. I argue that NJ is the most suitable tree inference method to use in yeast species descriptions, primarily because it is best at visually preserving the extent of sequence divergence between close relatives, which continues to be the primary criterion for yeast species delineation. The relevance of bootstraps in application of the phylogenetic species concept is discussed. This article is protected by copyright. All rights reserved.

Metschnikowia miensis f.a., sp. nov., isolated from flowers in Mie prefecture, Japan

Four yeast strains (RIFY 10001^T, RIFY 10002, RIFY 10003, and RIFY 10004) were isolated from flowers growing in fields of mustard and broad beans in Japan. Ascospore formation was not observed. Sequence analysis of the D1/D2 domain of the large subunit ribosomal RNA (LSU rRNA) gene of the four strains indicated that they belong to the genus Metschnikowia and are closely related to Metschnikowia hawaiiana strain CBS 9146^T and Metschnikowia orientalis strain CBS 10331^T. The D1/D2 domain of the LSU rRNA gene and internal transcribed spacer regions of strain RIFY 10001^T were 85.7% identical to those of M. hawaiiana strain CBS 9146^T. All four strains were distinguished from the M. hawaiiana strain CBS 9146^T by their inability to ferment glucose. Hence, these four strains are novel species and were named as Metschnikowia miensis (holotype: RIFY 10001^T; isotypes: NBRC 112445^T = CBS 14749^T).