Skip to main content

Proposal for an Expanded Distichlis (Poaceae, Chloridoideae): Support from Molecular, Morphological, and Anatomical Characters

Buy Article:

$23.00 plus tax (Refund Policy)


The Distichlis clade comprises Distichlis (7 species), Monanthochloë (2), and Reederochloa (1). All species except D. distichophylla (endemic to Australia) and D. spicata (widespread in the New World) are restricted either to North or South America. We investigated phylogenetic relationships within the clade using chloroplast (trnL–F and ndhF) and nuclear ribosomal (internal transcribed spacers and 5.8S) DNA sequences. We also studied lemma micromorphology, leaf blade anatomy, macromorphology, and biogeography in a phylogenetic context. The Distichlis clade is strongly supported in the molecular analyses. A morphological synapomorphy for the clade is the presence of a single papilla on the center of each subsidiary cell of lemma stomata. Other diagnostic features include dioecy, rhizomes or stolons, conspicuously distichous leaves, 5–13 lemma nerves, dumbbell- or flask-shaped bicellular microhairs with sunken basal cells, and growth in alkaline or saline soils. The nuclear and chloroplast phylogenies indicate that Monanthochloë and Reederochloa are nested within a paraphyletic Distichlis, and a number of structural characters, including leaf blade length, number of spikelets per inflorescence, and number of florets per spikelet, also fall within the range of variation in Distichlis. Therefore, we propose expanding the circumscription of Distichlis to include Monanthochloë and Reederochloa, and make the following new combinations: Distichlis acerosa, D. eludens, and D. littoralis. Biogeographical analysis revealed that the group likely originated in North America followed by a number of long-distance dispersal events, including back dispersals.


Document Type: Regular Paper


Publication date: 2008-07-01

More about this publication?
  • Access Key
  • Free ContentFree content
  • Partial Free ContentPartial Free content
  • New ContentNew content
  • Open Access ContentOpen access content
  • Partial Open Access ContentPartial Open access content
  • Subscribed ContentSubscribed content
  • Partial Subscribed ContentPartial Subscribed content
  • Free Trial ContentFree trial content
Cookie Policy
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more