A new species and a new combination in Phaeostemma (Apocynaceae, Asclepiadoideae, Gonolobinae)

Abstract

Phaeostemma surinamensis Morillo & Krings, sp. nov., a new species of Apocynaceae (Asclepiadoideae, Gonolobinae) is described and illustrated, and the new combination Phaeostemma fucata (Woodson) Morillo & Krings, comb. nov., is made. The new species, known only from a lowland wet forest of Suriname, seems to be closely related to P. fucata, which is an endemic to Ptari-tepui, a sandstone mountain in the southeastern edge of the Venezuelan Guayana.

A New Species in the <I>Matelea palustris</I> Complex (Apocynaceae, Asclepiadeae) and a Synopsis of the Complex in the Guianas and Northern Brazil

“…Distinct staminal corona elements are also found in T. cubensis; they are more reduced in T. fuscula, separating the latter and Anemotrochus from Matelea s.str. as currently circumscribed by Morillo (2012) and Morillo & Krings (2014). Further characters possibly segregating the new genera from Matelea s.str.…”

“…Matelea sensu Woodson comprises at least 260 species, and several attempts have been made to describe smaller natural genera (e.g. Stevens 2001;Morillo 2012Morillo , 2013Morillo , 2015Morillo & Krings 2014). However, as Krings (2011: 730) stated, "The synorganization of androecium and gynoecium appears to have facilitated such a myriad of gynostegial structural variation … that it is at times difficult to discern relationships, much less morphological synapomorphies, in the absence of a resolved phylogeny".…”

“…(2008), even though this was based only on a single partial sequence (trnLF, 370 bp). The other option is to circumscribe the two lineages as independent genera, following the pattern started by Stevens (2001), and continued by Morillo (2012Morillo ( , 2013Morillo ( , 2015 and Morillo & Krings (2014), who separated several genera from the large pool of Matelea mostly based on morphological criteria. While the recognition of small segregate genera in Matelea counters the general trend in Asclepiadoideae to amalgamate small genera into large ones (Goyder 2004;Liede-Schumann & al.…”

“…Current publications tend to reassess several of these genera or even describe new ones (e.g. Stevens 2001;Goyder 2006;Stevens & Morales 2009;Morillo 2012Morillo , 2013Morillo & Krings 2014). A recent phylogenetic study in Metastelma R. Br.…”