Transfer of Lejeunea huctumalcensis to Physantholejeunea (Lejeuneaceae, Porellales) Aleksandra Czumay A , Shanshan Dong A , Armin Scheben A , Alfons Schäfer-Verwimp B , Kathrin Feldberg C and Jochen Heinrichs C,D A Department of Systematic Botany, Georg August University Göttingen, Untere Karspüle 2, D-37073 Göttingen, Germany. B Mittlere Letten 11, D-88634 Herdwangen Schönach, Germany. C Systematic Botany and Mycology, Faculty of Biology, University of Munich (LMU), Menzinger Straße 67, D-80638 Munich, Germany. D Corresponding author. Email: jheinrichs@lmu.de Abstract. Phylogenetic analyses of a three-marker dataset of Lejeuneaceae (chloroplast genome rbcL gene and trnL–trnF region, and nuclear ribosomal ITS1–5.8S-ITS2 region) resolve Lejeunea huctumalcensis (synonym Ceratolejeunea dussiana) in a well supported lineage with Physantholejeunea portoricensis. Representatives of Lejeunea and Ceratolejeunea form independent lineages. Physantholejeunea and L. huctumalcensis share the presence of ocelli, pycnolejeuneoid innovations and keeled perianths, with keels forming horn-like projections. On the basis of the molecular phylogenetic and morphological evidence, we transfer L. huctumalcensis to Physantholejeunea. Received 5 September 2013, accepted 23 October 2013, published online 20 December 2013 Introduction Lejeuneaceae represent the most speciose family of leafy liverworts with some 1700 species (He and Zhu 2011) in 68 currently accepted genera (Gradstein 2013). This family has its centre of diversity in the humid tropics and constitutes an important component of the cryptogamic, especially epiphytic, diversity (Ye et al. 2013). The taxonomy of Lejeuneaceae is regarded as notoriously difficult and numerous divergent classifications have been proposed (Spruce 1884; Mizutani 1961; Grolle 1983; Schuster 1994, 2001). Lejeuneaceae subtribe Lejeuneinae was recently set up to include five genera – namely, Bromeliophila R.M.Schust., Harpalejeunea (Spruce) Schiffn., Hattoriolejeunea Mizut., Lejeunea Lib. and Microlejeunea Steph. – which share the presence of lejeuneoid innovations, small oil bodies and, with a few exceptions, a proximal hyaline papilla, (Gradstein 2013). Molecular data demonstrated that Bromeliophila is an element of Lejeuneaceae subtribe Cyclolejeuneinae rather than subtribe Lejeuneinae (Heinrichs et al. 2013) and allowed the separation of the genera Harpalejeunea, Lejeunea and Microlejeunea by the presence or absence of ocelli, and differences in underleaf shape (Dong et al. 2013). The monospecific genus Hattoriolejeunea has so far not been included in a molecular phylogenetic study. According to the results of Dong et al.(2013), Lejeunea can be separated from Harpalejeunea and Microlejeunea by the lack of ocelli, but a few taxa seem to contradict this otherwise clear separation (Wei and Zhu 2013). Reiner-Drehwald and Ilkiu-Borges (2007) presented a detailed morphological investigation of the neotropical Ceratolejeunea dussiana (Steph.) Dauphin and synonymised it with Lejeunea huctumalcensis Lindenb. & Gottsche, despite its divergent morphology, including the presence of suprabasal or distant basal ocelli as well as lejeuneoid and pycnolejeuneoid gynoecial innovations. Although the presence of ocelli plus pycnolejeuneoid innovations opposes a relationship to Lejeunea sensu Dong et al.(2013), the systematic position of C. dussiana–L. huctumalcensis has not yet been tested using molecular evidence. Here, we present the results of a molecular phylogenetic study of 81 species of Lejeuneaceae tribe Lejeuneeae, including two accessions of L. huctumalcensis. We demonstrate that this taxon is related neither to Ceratolejeunea J.B.Jack & Steph. nor to Lejeunea but forms a robust monophyletic lineage with Physantholejeunea portoricensis (Hampe & Gottsche) R.M.Schust. On the basis of the outcome of our phylogenetic analyses and accompanying morphological evidence, we transfer L. huctumalcensis to Physantholejeunea R.M.Schust. Materials and methods Taxa studied, DNA extraction, PCR amplification and sequencing Upper parts of a few gametophytes were isolated from several specimens of Lejeunea huctumalcensis and Ceratolejeunea (Appendix 1). Total genomic DNA was purified using Journal compilation Ó CSIRO 2013 www.publish.csiro.au/journals/asb CSIRO PUBLISHING Australian Systematic Botany, 2013, 26, 386–392 http://dx.doi.org/10.1071/SB13039