Does leaf anatomy aid in species identification of Butia (Arecaceae)?

Butia is a neotropical genus of palms whose identification is based mostly on characters of external morphology, which are sometimes variable or inadequate for species differentiation. A recent study by Sant’Anna-Santos et al., and published as an Editor’s Choice article in AoBP, aimed to verify if leaf anatomical characteristics of 18 Butia species could used to identify species and if these could corroborate phylogenetic relationships within the genus. They also propose an anatomical key to assist in species identification within the Butia genus.

SEM image of Butia capitate
Stegmata cells of Butia capitate (Mart.) Becc. (cryofractured pinnae at scanning electron microscopy). Image credit: Sant’Anna-Santos et al.

Sant’Anna-Santos and his colleagues collected pinnae from all 18 species and analysed them with light and scanning electron microscopy. An anatomical key was created with the aid of Xper2 software, based on the importance of anatomical characters to distinguish species. All studied species had features in common (an isobilateral mirrored mesophyll, amphistomatic leaves and secondary vascular bundles with sclerenchymatic sheath reinforcement connected to the hypodermis). Among the species studied, B. marmorii and B. matogrossensis showed exclusive anatomical characters and were easily identifiable. For the other species, up to five characters were sufficient for identification. This paper highlights reliable anatomical characters of the pinnae that allow the identification of the recognised species of Butia through a purely anatomical key, in which specific identifications are performed using a set of up to five characters. Leaf anatomy, already used to support new taxa in related genera, can also be useful to validate questionable Butia species and differentiate between similar species, but surprisingly do not reflect the proposed phylogenetic relationship between species of this genus.

Researcher spotlight

Bruno Sant'Anna-Santos

Bruno F. Sant’Anna-Santos holds a degree in Agronomy from the Federal University of Viçosa, Brazil in 2003. In 2008 he completed a PhD in Botany (plant anatomy) under the supervision of Professor Aristea Alves Azevedo at the same university. Currently, he is a professor at the Department of Botany and a researcher in the Postgraduate Program in Agronomy at the Federal University of Paraná, Brazail.

Bruno’s latest research focusses on identifying anatomical characters that will aid in understanding the phylogenetic relationship of species complexes of Palms (most notably the Attaleinae subtribe). Additionally, he uses microscope analyses, in association with plant physiology techniques, to study the effects of abiotic stress in native Brazilian plants and important crop species.

Reference List

Sant’Anna-Santos, B. F., Santos, S. A. dos, Nunes, E. L. P., Francino, D. M. T., & Carvalho Júnior, W. G. O. (2018). Does leaf anatomy aid in species identification of Butia (Arecaceae)? AoB PLANTS, 10(4). https://doi.org/10.1093/aobpla/ply046