The hydrochorous Amazonian genus Glandonia (Malpighiaceae): new records, morphoanatomy updates and taxonomic contributions

Abstract

Glandonia is a rare genus comprising three species confined to Amazonian rainforest. Glandonia macrocarpa has been documented in some localities of the lower Rio Negro, in the municipality of Manaus, Brazil. Glandonia prancei is represented by only a few herbarium specimens, which were collected along the Madeira and Purus rivers in the 1960s and 70s. A recent record of G. prancei was discovered while analyzing collections of G. macrocarpa, providing a new locality where we found and collected G. prancei. Glandonia williamsii, which had not been recorded in Brazil for the past three decades, was collected in the upper Rio Negro in this study. This work reexamines the taxonomy of the genus, based on fieldwork and herbarium specimens, and includes notes on morpho-anatomy, distribution and phenology. New morpho-anatomical characters are provided to better describe the species (e.g., outline of epidermal cell walls of the leaf, arrangement of petiolar vascular system, bracteole gland surface, and distribution of glands on the leaf blade and petals).

Leaf Morphoanatomy of Diploon Cronquist (Sapotaceae Juss.)

“…The shape and arrangement of the vascular system of the petiole and midrib have been deemed useful in plant systematics (Araújo et al 2010, Leandro et al 2015, Coutinho et al 2016, Feio et al 2018, Guesdon et al 2018, Pereira et al 2018. Metcalfe & Chalk (1950) described eight shapes for the petiole of Sapotaceae.…”

Taxonomic revision of Mcvaughia W.R.Anderson (Malpighiaceae): notes on vegetative and reproductive anatomy and the description of a new species

“…Glandonia species also show leaf glands varying from two to four basilaminar and a few to several laminar glands, which can be conspicuous or inconspicuous to the naked eye (Guesdon et al 2018). Stalked glands have been recorded in the literature for Banisteriopsis (Araújo and Meira 2016; Nery et al 2017), and Stigmaphyllon (Almeida and Mamede 2016); as well, sessile glands are known in Diplopteryspubipetala (Possobom et al 2010), and sessile to immersed glands in Amorimia (Mello et al in press.)…”

“…Stalked glands have been recorded in the literature for Banisteriopsis (Araújo and Meira 2016; Nery et al 2017), and Stigmaphyllon (Almeida and Mamede 2016); as well, sessile glands are known in Diplopteryspubipetala (Possobom et al 2010), and sessile to immersed glands in Amorimia (Mello et al in press.) and Glandonia species (Guesdon et al 2018). Dorsiventral mesophyll with a single layer of palisade parenchyma and paracytic stomata are quite similar in all the three genera and commonly found in Malpighiaceae species, as reported by Araújo et al (2010), Almeida et al (2017), and Guesdon et al (2018).…”

“…Since then, those genera have been placed in the so-called Mcvaughioid clade, one of the three early diverging lineages of Malpighiaceae: Byrsonimoids, Acridocarpoids, and Mcvaughioids (Davis and Anderson 2010). The Mcvaughioid clade comprises eight species distributed in three genera: Burdachia , Glandonia , and Mcvaughia (Anderson 1981; Reis e Silva 2007; Amorim and Almeida 2015; Guesdon et al 2018). About three decades later the description of Mcvaughia , the second species of the genus was discovered and described for the restinga vegetation and coastal dunes from the northern state of Sergipe, Brazil (Amorim and Almeida 2015).…”

The taxonomic value of leaf anatomy for species Byrsonima: a difficult genus of Malpighiaceae Juss.

“…It provides additional informative features which helps to understand its morphological evolution (Metcalfe & Chalk 1979;Endress et al 2000). Leaf anatomy is widely used as an aid in flowering plants taxonomy, especially in groups with taxonomic problems, as in Malpighiaceae (Metcalfe & Chalk 1957;Gomes et al 2009;Araújo et al 2010;Almeida-Jr et al 2013;Almeida et al 2017;Guesdon et al 2018;Almeida et al 2019;Araújo et al 2020). Even though leaf anatomy of Byrsonima species has been explored in previous studies, few have listed features that can be attributed to a new classification system for the genus (Araújo et al 2010;Silva 2014).…”