Phylogenetic analysis of Microlicieae (Melastomataceae), with emphasis on the re-circumscription of the large genusMicrolicia

Abstract

Microlicieae are a monophyletic tribe comprising seven genera: Chaetostoma, Lavoisiera, Microlicia s.s., Poteranthera, Rhynchanthera, Stenodon and Trembleya. Microlicia s.s. includes 172 species predominantly distributed in the campo rupestre of Brazil. Its delimitation is complex because the generic boundaries, mostly with Lavoisiera and Trembleya, are unclear. Here we present a phylogenetic analysis for Microlicieae focusing on Microlicia s.s., with the specific goals: (1) to test the monophyly of Microlicia s.s.; (2) to investigate morphological characters that could help in circumscribing clades and/or genera in the tribe and (3) to provide an appropriate classification for Microlicia s.s. and related genera. This study was based on plastid (atpF-atpH, trnS-trnG), nuclear ribosomal (nrITS, nrETS) and nuclear low-copy (waxy) DNA sequences, through maximum likelihood and Bayesian inference analyses. The history of 12 morphological characters was estimated based on ancestral state reconstruction analyses. Our analysis shows Microlicia s.s. to be paraphyletic with Chaetostoma, Lavoisiera, Stenodon and Trembleya nested in it. Most characters traditionally used to diagnose these genera are homoplastic. We propose the inclusion of these four genera in a broadly circumscribed Microlicia s.l., and provide new combinations and names for their species. As here defined, Microlicieae has three genera, Rhynchanthera, Poteranthera and Microlicia s.l., Microlicia s.l. being the fourth richest genus in Melastomataceae with c. 245 species.

Systematics of the Trembleya sensu stricto clade of Microlicia (Melastomataceae, Lavoisiereae)

“…With about 275-300 species, the near-endemic Brazilian tribe Lavoisiereae DC., which has long been known by the later tribal name Microlicieae Naudin, is one of the richest clades of Neotropical Melastomataceae (Fritsch et al 2004;Versiane et al 2021;Pacifico and Almeda 2022). Currently, three genera are accepted, i.e.…”

Two new narrow endemic species of Microlicia (Melastomataceae, Lavoisiereae) from Serra do Porco Gordo, Bahia, Brazil

“…One of the largest genera of Neotropical Melastomataceae, Microlicia D.Don (ca 250 spp.) (Lavoisiereae) has more than 90% of its species endemic to Brazil (Versiane et al 2021, Pacifico and Almeda 2022a). It is a typical floristic element of mountains with campo rupestre vegetation (rupestrian grasslands), a long‐neglected Brazilian mountainous ecosystem with nutrient‐poor soils and remarkable rates of plant endemism (Versiane et al 2021, Pacifico and Almeda 2022a).…”

“…(Lavoisiereae) has more than 90% of its species endemic to Brazil (Versiane et al 2021, Pacifico and Almeda 2022a). It is a typical floristic element of mountains with campo rupestre vegetation (rupestrian grasslands), a long‐neglected Brazilian mountainous ecosystem with nutrient‐poor soils and remarkable rates of plant endemism (Versiane et al 2021, Pacifico and Almeda 2022a). In northeastern Brazil, this ecosystem is best developed on the Chapada Diamantina, a mountain range with unique species‐rich flowering plant communities forming a distinct biogeographic province (Colli‐Silva et al 2019), and a major area of endemism for Microlicia (Pacifico et al 2020).…”

“…During the last three decades, studies on the Bahian species of the genus have mostly been limited to species checklists (Zappi et al 2003, Santos and Silva 2005), an identification key (Woodgyer 2005), regional taxonomic treatments (Woodgyer and Lughadha 1995, Pataro et al 2017) and descriptions of new taxa (Wurdack 1995, Woodgyer and Zappi 2005, 2009, Almeda and Martins 2012, Pataro et al 2013, Jesus et al 2018, Pacifico and Almeda 2018, 2020a, b2020b, 2022b, Romero and Woodgyer 2018, Gali et al 2022). Within Lavoisiereae, species of Microlicia are recognized by their perennial woody habit associated with diplostemonous, mostly heteranthous flowers, elongate to somewhat reniform seeds with a reticulate–foveolate testa, and a base chromosome number of x = 12 (Versiane et al 2021, Pacifico and Almeda 2022a).…”

Microlicia deflexa and M. johnwurdackiana (Melastomataceae), two new species from the Brazilian Cerrado

“… Microlicia D.Don is a predominantly Brazilian genus composed of ca. 240 species ( Versiane et al 2021 ), with most species occurring in the campo rupestre from Minas Gerais, Bahia and Goiás States ( Romero 2003a , b ; Romero et al 2020 ) and about 49 species occurring in the cerrado phytophysiognomy. The species are generally characterised by solitary flowers or, in dichasia, reduced to one flower, with five to six occasionally nine petals, a superior or semi-inferior ovary with three to six locules and capsules dehiscing longitudinally from the apex to the base (basipetal) or from the base to the apex (acropetal) (see Versiane et al 2021 ).…”