. On the taxonomic position of Panicum aristellum (Poaceae: Panicoideae: Paniceae).

ZULOAGA, F. O., GIUSSANI, L. M. & MORRONE, O.

SYSTEMATIC BOTANY

American Society of Plant Taxonomist

Lugar: EEUU; Año: 2005 p. 1 - 2

0363-6445

    ABSTRACT. In a recent treatment, the genus Panicum was restricted to  subgenus Panicum based on molecular, morphological and anatomical data. Also, other species of Panicum were transferred to different genera of the Paniceae, such as Dichanthelium, Hymenachne, Phanopyrum, and Steinchisma, while the remaining American species of Panicum were temporarily place as incertae sedis taxa. Therefore, these incertae sedis species are in need of a new taxonomic status within the tribe. In this study, the taxonomic position of Panicum aristellum, an endemic species of central and southeastern Brazil, is evaluated using morphological and  anatomical characters, together with a molecular marker from the chloroplast, the ndhF. The sequence of Panicum aristellum was analyzed together with other species of the subfamily Panicoideae. As a result, this species grouped with the genus Canastra in a well supported clade. Several synapomorphies characterized the clade: caespitous plants, with keeled sheaths, aristate spikelets, scabrous bracts, the number of nerves of the glumes and lower lemma, the presence of a lower palea and lower flower, a non-indurate upper anthecium, and a similar geographical distribution. In addition, both species are C3 with non-Kranz anatomy. As a result, Panicum aristellum is transferred to Canastra and compared to putatively related genera within the Paniceae.