Glands on the foliar surfaces of tribe Cercideae (Caesapiniodeae, Leguminosae): distribution and taxonomic significance

Abstract

Large elongated glands occur on Cercideae leaf surfaces. Leaves of Bauhinia (55 taxa, 53 species), Cercis (1 species), Phanera (1 species), Piliostigma (2 species), Schnella (19 species) and Tylosema (1 species) were observed to determine location and relative number of glands. They were only observed on the abaxial leaf surface of 42 Bauhinia taxa. The glands were analyzed by light stereomicroscope and scanning electron microscopy. They are large (up to 270 µm long and 115 µm wide) and multicellular, containing lipophilic substances, probably volatile oils. Presence or absence and density of the glands in species of Bauhinia may be useful to determine species delimitation or distinction among infraspecific taxa. Higher density of glands is more common in species from "cerrado" (a savanna ecosystem) and "caatinga" (a semiarid ecosystem from northeast Brazil) areas. Bauhinia species devoid of foliar glands are frequently from humid forests.

The uncommon cavitated secretory trichomes inBauhinia s.s.(Fabaceae): the same roles in different organs

“…65 species (Leelavathi & Ramayya, ; Tucker et al ., ; Kumar et al ., ; Lersten & Curtis, , ; Curtis, Lersten & Lewis, ; Marquiafável et al ., ; Matos & Paiva, ; Duarte‐Almeida et al ., ). Among Cercideae, Bauhinia s.s. is distinct, with descriptions of such trichomes in the floral organs of 14 species (Leelavathi & Ramayya, ; Tucker et al ., ) and in leaves of 41 species (Baitello, ; Leelavathi & Ramayya, ; Rezende, Cardoso & Vannucci, ; Lusa & Bona, , Sá et al ., ; Duarte‐Almeida et al ., ). Therefore, the presence of cavitated secretory trichomes appears to be a potential synapomorphy of the Bauhinia s.s. clade (Duarte‐Almeida et al ., ).…”

“…Steud. have cavitated secretory trichomes in their flowers and leaves (Baitello, ; Rezende et al ., ; Duarte‐Almeida et al ., ; C. R. Marinho pers. observ.)…”

“…Reports of cavitated trichomes usually address aspects of distribution and morphology on the plant (Solereder, ; Metcalfe & Chalk, ; Uphof, ; Curtis et al ., ; Leelavathi & Ramayya, ; Lersten & Curtis, , ; Marquiafável et al ., ; Duarte‐Almeida et al ., ) and, more rarely, consider aspects of development (Carlquist, ; Tucker et al ., ; Kumar et al ., ; Matos & Paiva, ; Zhou et al ., ). Studies concerning the chemical nature and secretory process of the cavitated trichomes have been conducted for Centrolobium tomentosum Benth.…”

Beyond pollination: diversity of secretory structures during flower development in different legume lineages

“…2). Interestingly, although their presence is a wide condition in legumes, their distribution and morphology are highly variable and of potential systematic value for some groups such as cavitated trichomes in the genus Bauhinia (Duarte-Almeida et al 2015;Marinho et al 2016) and the trichomes present in species of the Caesalpinia clade (Ragonese 1973;Leelavathi & Ramayya 1983;Lersten & Curtis 1994;1996;Rudall et al 1994;Lewis & Schrire 1995;Simpson & Miao 1997;Pascal et al 2000;Warwick & Lewis 2009;Melo et al 2010) and in the genus Mimosa (Santos-Silva et al 2013). Our reports of floral secretory trichomes are original for 11 of the 15 species studied belonging to the Cassia, Dimorphandra, Mimosoideae and Papilionoideae clades.…”