A new species of cellular slime mold from southern Portugal based on morphology, ITS and SSU sequences

Abstract

Sampling soils to look for dictyostelids in southern Portugal we found an isolate that has a morphology that differed from any previously described species of the group. We sequenced the internally transcribed spacer (ITS) and small subunit (SSU) genes of the nuclear ribosomal RNA and found that both sequences are distinct from all previously described sequences. Phylogenetic analyses place the new species in dictyostelid Group 3 (Rhizostelids) together with D. potamoides, with which it shares 65.8% identity for ITS and 96.6% for SSU. In this paper we describe a new species of cellular slime mold, Dictyostelium ibericum, based on morphological and molecular characters. It is a small species with polar granules in its spores.

• cellular slime molds
• Europe
• molecular data
• morphology
• taxonomy

We thank especially J. Landolt (Shepherd University, USA) for carefully examining D. ibericum material during MR’s visit to his laboratory in 2005. We also thank members of the Leandro Sastre lab at Instituto de Investigaciones Biomédicas, CSIC, Madrid, for help in isolating D. ibericum DNA, M. Nelson from University of York for her help with lab work and Mats Thulin (Uppsala University, Sweden) for help with translating the species diagnosis into Latin. This research was supported by grants from Ministry of Education and Science of Spain (REN2002-00445/GLO and CGL2005-00320/BOS) to C. Lado, an I3P grant to MR and a research grant from the Leverhulme Trust to SB. MR’s stay at the Universities of Ohio and Shepherdstown, USA, was supported by a grant from the National Science Foundation (GBE-0316284).