Tatiana Teixeira de Souza Chies

New Combinations Within the Briza Complex (Poaceae, Pooideae, Poeae)

Abstract.  Briza L. (Poaceae, Pooideae, Poeae) is a genus with a controversial circumscription, being either considered sensu lato, including Eurasian and South American species (e.g., Longhi-Wagner, 1987), or sensu stricto, including only four Eurasian species and being considered closely related to the South American species, forming the Briza complex (Matthei, 1975). According to recent phylogenetic analysis, Briza should be accepted sensu stricto, with four Eurasian species, as proposed by Matthei (1975) and other authors. The American species, which were previously published under Briza s.l. or under the genera Calotheca Desv., Chascolytrum Desv., Erianthecium Parodi, Gymnachne Parodi, Lombardochloa Roseng. & B. R. Arrill., Microbriza Parodi ex Nicora & Rúgolo, Poidium Nees, and Rhombolytrum Link, should be included within Chascolytrum, the oldest generic name published for the American species of the complex. As a result, the following 13 new combinations are proposed in Chascolytrum: C. ambiguum (Hack.) Essi, Longhi-Wagner & Souza-Chies, C. bidentatum (Roseng., B. R. Arrill. & Izag.) Essi, Longhi-Wagner & Souza-Chies, C. brachychaetum (Ekman) Essi, Longhi-Wagner & Souza-Chies, C. brasiliense (Nees ex Steud.) Essi, Longhi-Wagner & Souza-Chies, C. brizoides (Lam.) Essi, Longhi-Wagner & Souza-Chies, C. bulbosum (Parodi) Essi, Longhi-Wagner & Souza-Chies, C. calotheca (Trin.) Essi, Longhi-Wagner & Souza-Chies, C. itatiaiae (Ekman) Essi, Longhi-Wagner & Souza-Chies, C. koelerioides (Trin.) Essi, Longhi-Wagner & Souza-Chies, C. monandrum (Hack.) Essi, Longhi-Wagner & Souza-Chies, C. poomorphum (J. Presl) Essi, Longhi-Wagner & Souza-Chies, C. rhomboideum (Link) Essi, Longhi-Wagner & Souza-Chies, and C. uniolae (Nees) Essi, Longhi-Wagner & Souza-Chies. The names Poa koelerioides Trin., Poa tumidula Steud., Poidium brasiliense Nees ex Steud., and Rhombolytrum berteroanum E. Desv. are lectotypified.

Three new taxa of Chascolytrum (Poaceae, Pooideae, Poeae) from South America.

Abstract Two new species and one new variety of Chascolytrum Desv. (Poaceae) are described and illustrated. Chascolytrum latifolium Essi, Souza-Chies & Longhi-Wagner and C. juergensii var. angustilemma Essi, Souza-Chies & Longhi-Wagner occur in the southern Brazilian highlands, while C. altimontanum Essi, Souza-Chies & Longhi-Wagner occurs in the Bolivian highlands. Chascolytrum latifolium is related to C. subaristatum (Lam.) Desv., but differs mainly by the wider leaf blades and by some characteristics of the palea. Chascolytrum altimontanum is related to C. paleapiliferum (Parodi) Matthei and C. subaristatum, the main differences being the presence of flattened trichomes at the lemma base and the shape of the spikelets. Specimens of all these new taxa were included in a parallel molecular analysis, with the results supporting the new taxa as genetically divergent from the closest morphologically related species. In addition, Briza juergensii Hack. is transferred to Chascolytrum for the new combination C. juergensii (Hack.) Essi, Souza-Chies & Longhi-Wagner.

THE STUDY OF BIODIVERSITY AND PLANT EVOLUTION THROUGH MOLECULAR MARKERS AND CYTOGENETICS: EXAMPLES IN IRIDACEAE AND POACEAE.

We present here a review of the use of molecular markers and cytogenetic data, applied to the detection of plant biodiversity. We mentioned a few examples o...

A Synopsis of Briza, Brizochloa, and Chascolytrum (Poaceae, Pooideae, Poeae)1

Abstract A taxonomic revision of the Briza complex was carried out, including the genera accepted by past authors as subgenera or sections of Briza s.l. (Briza L., Calotheca Desv., Chascolytrum Desv., Lombardochloa Roseng. & B. R. Arrill., Microbriza Parodi ex Nicora & Rúgolo, and Poidium Nees) as well as other related genera (Brizochloa V. Jirásek & Chrtek, Erianthecium Parodi, Gymnachne Parodi, and Rhombolytrum Link). As a result of the morphological analysis presented here, confirmed by other studies with molecular data, Briza is accepted with three Eurasian species, Brizochloa is accepted with one species, and a new circumscription for the genus Chascolytrum is proposed. This new circumscription includes all the accepted South American species that were previously assigned to the other genera cited above. Descriptions and illustrations of three species and one variety of Briza, one species of Brizochloa, and 22 species and two varieties of Chascolytrum are provided, as well as IUCN conservation status for most species. A new status is proposed for Briza media f. caucasica Marcow.: Briza media var. caucasica (Marcow.) Essi, Longhi-Wagner & Souza-Chies. The following name is newly transferred: Chascolytrumrufumvar. sparsipilosum(Roseng., B.R.Arrill. & Izag.) Essi, Longhi-Wagner & Souza-Chies [≡ Briza rufa var. sparsipilosa Roseng., B. R. Arrill. & Izag.]. Keys for genera and species are also provided. Lectotypifications are provided for Briza neesii Döll and Briza triloba Nees.