Luzula sect. Luzula (Juncaceae) in the South-Eastern Alps: morphology, determination and geographic distribution

Abstract

Bacic T., Dolenc Koce J. and Jogan N. 2007. Luzula sect. Luzula (Juncaceae) in the South-Eastern Alps: morphology, determination and geographic distribution. Bot. Helv. 117: 75 – 88. Within the genus Luzula, the type section (Luzula sect. Luzula) is particularly variable and taxonomically diverse. Eight taxa of Luzula sect. Luzula occur in the Alps. While these taxa have distinct caryotypes, their identification based on morphological traits has remained problematic, and their geographic distribution is insufficiently known. A morphometric study was performed on herbarium material from Slovenia and neighbouring regions to identify additional discriminative characters and to establish the distribution of taxa within the territory of Slovenia. We measured 52 plant traits on 233 herbarium sheets and analysed the data with multivariate statistical techniques. Results showed a clear differentiation between L. campestris and the seven other taxa, which were only discriminated by combinations of several quantitative characters. In general, ripe fruits are required for a reliable determination. Four of the eight taxa are widespread in Slovenia: L. campestris and L. divulgatiformis in the lowlands (mostly 900 m), and L. multiflora across a broad altitudinal range (200–1900 m). Two taxa (L. divulgata and L. alpina) proved to be rare in Slovenia, and two taxa (L. sudetica and L. pallescens), previously reported for the area, were not confirmed. Distribution maps are presented for the six Slovenian taxa, and a new determination key is proposed for the eight Alpine taxa.