Phylogeny and historical biogeography analysis support Caucasian and Mediterranean centres of origin of key holoparasitic Orobancheae (Orobanchaceae) lineages

The extensive diversity of the tribe Orobancheae, the most species-rich lineage of holoparasitic Orobanchaceae, is concentrated in the Caucasus and Mediterranean regions of the Old World. This extant diversity has inspired hypotheses that these regions are also centres of origin of its key lineages, however the ability to test hypotheses has been limited by a lack of sampling and phylogenetic information about the species, especially in the Caucasus region. First, we assessed the phylogenetic relationships of several poorly known, problematic, or newly described species and host-races of four genera of Orobancheae occurring in the Caucasus region–Cistanche, Phelypaea, Phelipanche and Orobanche–using nuclear ribosomal (ITS) and plastid (trnL–trnF) sequence data. Then we applied a probablistic dispersal-extinction-cladogenesis model of historical biogeography across a more inclusive clade of holoparasites, to explicitly test hypotheses of Orobancheae diversification and historical biogeography shifts. In sum, we sampled 548 sequences (including 196 newly generated) from 13 genera, 140 species, and 175 taxa across 44 countries. We find that the Western Asia (particularly the Caucasus) and the Mediterranean are the centre of origin for large clades of holoparasitic Orobancheae within the last 6 million years. In the Caucasus, the centres of diversity are composed both of long-branch taxa and shallow, recently diversified clades, while Orobancheae diversity in the Mediterranean appears to represent mainly recent diversification.

The biogeography of the megadiverse genus Anthurium (Araceae)

The tropics of the New World are a biodiversity hotspot, the genus Anthurium being an example of a megadiverse taxon with currently > 1000 described species. In this study, we provide detailed information on species distributions and analyse patterns of diversity and endemism, with a particular focus on the comparison of epiphytic and terrestrial congenerics. Using a dataset of occurrence records for 1041 Anthurium spp. (c. 98% of the genus), we modelled geographical species distributions using climate-based species distribution models or buffered convex hulls depending on the number of occurrences available. We identified nine bioregions using cluster analysis. The Andean slopes, Central America, the Chocó and the Atlantic Forest in eastern Brazil are the most important centres of diversity for Anthurium, whereas endemism is highest in the central Andes. These macroecological patterns agree largely with diversity centres for other Neotropical plant groups. Epiphytes, accounting for about two-thirds of all species, have much larger range sizes than terrestrials, but do not differ in elevational ranges. Almost 40% of all Anthurium spp. are restricted to the lowlands, but a few species grow at elevations of almost 4000 m. Although individual species have an average elevation range of just c. 1000 m, there are taxa that cover > 3500 m of elevation.

Cytogeography and morphological characterisation of a taxonomic, polyploid complex of Mimosa (Leguminosae) from subtropical South America

Mimosa subseries Dolentes Barneby and Brevipedes Barneby are ecologically and morphologically high-diversified infrageneric taxa of this genus in southern South America. We performed a cytogenetical and morphological analysis of both subseries. Chromosome numbers from accessions throughout the area of distribution were studied. The chromosome numbers 2n=8x=104 for M. dolens subsp. callosa (Benth.) Barneby, M. dolens subsp. acerba varieties acerba (Benth.) Barneby, latifolia (Benth.) Barneby and rudis (Benth.) Barneby, M. dolens subsp. rigida var. rigescens (Benth.) Barneby, var. anisitsii (Lindm.) Barneby and var. foliolosa (Benth.) Barneby; and 2n=4x=52 for M. sceptrum Barneby, M. aff. custodis Barneby and M. dolens var. pangloea Barneby are presented for the first time. Their karyotypes were symmetric, with small chromosomes. There were several areas with taxa growing in sympatry, occasionally with intermediate forms. No diploids were found, which suggests the presence of either a declining polyploid complex or ancient polyploidy in the clade of southernmost representatives of M. series Mimosa, the most derived of the genus. Some vegetative, inflorescence and carpological characters seem to be associated with chromosome duplication. The distribution pattern of the cytotypes suggests events of chromosome duplication in centres of diversity and expansion of octoploids to the southernmost areas of distribution. Our findings support the importance of polyploidy in the morphological diversity, distribution and speciation of this complex.

Morphological and molecular systematics of the ‘Monanchora arbuscula complex’ (Poecilosclerida : Crambeidae), with the description of five new species and a biogeographic discussion of the genus in the Tropical Western Atlantic

Monanchora Carter, 1883 is a genus of shallow-water marine sponges comprising 16 species distributed worldwide, two of them in the Tropical Western Atlantic (TWA): M. arbuscula (Duchassaing & Michelotti, 1864) and M. brasiliensis Esteves, Lerner, Lôbo-Hajdu & Hajdu, 2012. The former species stands out as one of the most variable demosponges, and is very similar in spicule complement and in secondary metabolite chemistry to the Mediterranean/eastern Atlantic Crambe crambe (Schmidt, 1862), type species of Crambe Vosmaer, 1880. The aim of the present study was to revise the genus Monanchora in the TWA. In addition, we critically analyse the monophyly of Crambe and Monanchora. Maximum Likelihood and Bayesian Inference analyses of 28S and 16S rRNA sequences of the latter genera, and a redescription of the ‘M. arbuscula complex’, revealed three species: M. arbuscula s.s., M. coccinea, sp. nov. and a new species of Acarnidae – Iophon parvachela, sp. nov. Three other new species from the TWA previously assigned to Monanchora were revealed by morphological analyses, and are also described: M. bahamensis, sp. nov., M. megasigmifera, sp. nov. and a new species of Chondropsidae – Batzella catarinensis, sp. nov. A key for species identification is provided. Our results suggest that the Eastern Brazil and Southeastern Brazil Ecoregions may represent centres of diversity for Monanchora in the TWA.

Miliusa sahyadrica, a new species of Annonaceae from the Western Ghats, India

Miliusa Leschenault ex A. de Candolle (1832: 213) is a Paleotropical genus in the family Annonaceae with about 60 species distributed mostly to the Austral-Asiatic region, ranging from India, Sri Lanka, Bhutan, Bangladesh, Myanmar, Thailand, Indonesia, Malay Islands, Philippines, Papua New Guinea to Australia and New Zealand (Mols & Keßler 2003,Chaowasku & Keßler 2013, Chaowasku et al. 2013). According to molecular phylogenetic analysis, the genus is placed in subfamily Malmeoideae, tribe Miliuseae (Chatrou et al. 2012). Thailand and India are considered as the centres of diversity for Miliusa with more than twenty species each (Mols & Keßler 2003, Chaowasku & Keßler 2013, Chaowasku et al. 2013, Turner 2015). A total of 23 species and one variety of the genus are so far recorded from India (Mitra 1993, Karthikeyan et al. 2009, Turner 2015, Page & Nerlekar 2016, Page et al. 2016, Josekutty et al. 2016, Karuppusamy & Richard 2016). Among these, 15 species and one variety are reported from the Western Ghats of India. Except for four species, namely M. indica Leschenault ex A. de Candolle (1832: 213), M. horsfieldii (Bennett 1840: 165) Pierre (1881: 38), M. tomentosa (Roxburgh: 1795: 31. t. 35.) Sinclair (1955: 378) and M. velutina (Dunal) Hooker & Thomson (1855: 151), all are endemic to that region (Nayar et al. 2014). As a whole, the genus is phytogeographically significant to Western Ghats with 71% of the species being endemics, which makes the genus more important from conservation point of view.

Lifting the curtain on our knowledge on New Guinean Benstonea (Pandanaceae)

New Guinea is one of the centres of diversity of Benstonea (Pandanaceae), a genus distributed from India to Fiji. Ten species were previously recognised on this island and further field observations, accompanied by the study of available herbarium material have brought new insights into species delimitations within a group of caespitose species with a solitary terminal infructescence. The taxonomical identity of Benstonea odoardoi is elucidated and is considered here as a synonym of Benstonea lauterbachii. Three new combinations and a new name—based on names of Pandanus species previously treated as synonyms of Benstonea odoardoi—are proposed for four distinct species belonging to this group of caespitose species and restricted to Indonesian New Guinea and Papua New Guinea. Finally, Pandanus bintuniensis is here considered as a synonym of Benstonea permicron.

Bulbophyllum paramjitii (Orchidaceae: Epidendroideae: Malaxideae): a new species from Sikkim Himalaya, India

Bulbophyllum Petit-Thouars (1822) is one of the largest orchid genera with about 2200 taxa, widely distributed in the tropics (Vermeulen 2014). The main centres of diversity are Asia-Pacific (1700 species), Madagascar (200 species) and New Guinea (600 species). Based on evidence from morphological and molecular data, Vermeulen (2014) recommended a wider circumscription of Bulbophyllum.