Andrew Henderson

Phylogenetic analysis of molecular data from species within subtribe Salaccinae resolved three well-supported clades, and these are also supported by morphological data. Two of these clades have been recognized previously at the generic level, Eleiodoxa and Salacca. Here, the third clade is described as a new genus, Neosalacca.

A DNA sequence-based phylogeny and a morphology-based revision of the tribe Caryoteae are presented. Results of the phylogenetic analysis showed that one of the three genera, Wallichia, should be included in Arenga. Species of Wallichia are hereby transferred to Arenga, and one species of Arenga is transferred to Caryota. Analysis of morphological data from over 1500 herbarium specimens resulted in recognition of 24 species of Arenga and 13 species of Caryota. These species are distributed throughout the Asian tropics and subtropics, from southwestern India to Vanuatu, and from southern China and the Ryukyu Islands to northeastern Australia. Nomenclature, descriptions, and distribution maps are provided for all species, including the new combinations, as well as notes on distribution, habitat, reproductive biology, and etymology.

The palm family (Arecaceae) has a rich history of phylogenetic research, including several recent phylogenomic studies. However, densely sampled phylogenomic datasets for larger palm clades – such as subfamilies – are still few in number. We used target sequence capture to obtain data for 971 nuclear genes across 421 (ca. 80%) species in the subfamily Coryphoideae. We inferred a robust phylogenetic tree to address systematic issues in the subfamily, specifically the relationships among tribes Cryosophileae, Sabaleae, Phoeniceae and Trachycarpeae, the affinities of seven genera in Trachycarpeae that are not currently assigned to any subtribe, and the monophyly of genera across the subfamily. We recovered relationships among tribes that are in accordance with other major nuclear phylogenomic datasets, but that are incongruent with trees derived from plastome sequences. Importantly, the placement of tribe Phoeniceae (the date palms) remains contentious. Our tree recovered with high support the relationship of all unplaced Trachycarpeae genera, paving the way for an updated classification. Most genera were resolved as monophyletic except for Livistona and all three genera of tribe Caryoteae, calling for a revision of generic limits. Our tree clarifies the relationships of many fan palm species for the first time, allowing for future studies of diversification, trait evolution or biogeography.

Two species of Iriartella were recognized in the most recent revision of the genus. Molecular data appeared to show that only one species should be recognized. However, an analysis of the molecular data, together with examination of morphological data from herbarium specimens, appears to support the recognition of two species.

Distributed across two continents and thousands of islands, the Asian tropics are among the most species-rich areas on Earth. The origins of this diversity, however, remain poorly understood. Here, we reveal and classify contributions of individual tropical Asian regions to their overall diversity by leveraging species-level phylogenomic data and new fossils from the most species-rich Asian palm lineage, the rattans and relatives (Arecaceae, Calamoideae). Radiators (Borneo) generate and distribute diversity, incubators (Indochina, New Guinea, and Sulawesi) produce diversity in isolation, corridors (Java, Maluku, Sumatra, and the Thai-Malay Peninsula) connect neighboring regions, and accumulators (Australia, India, Palawan, and the Philippines) acquire diversity generated elsewhere. These contrasting contributions can be explained by differences in region size and isolation, elucidating how the unique island-dominated geography of the Asian tropics drives their outstanding biodiversity.

A revision of Iguanura was carried out based on morphological data. Six hundred and seventy herbarium specimens were examined and scored for 15 quantitative and 25 qualitative variables. Application of the Phylogenetic Species Concept to 27 preliminary species resulted in recognition of 31 phylogenetic species. Of these, nine are recognized as new (I. beccarii, I. bruneiensis. I. exilis, I. grandis, I. lunata, I. mogeae, I. montana, I. sarawakensis, I. tomentosa). Nomenclature, descriptions, and distribution maps are provided for all species. Images of the type specimens of all new species are provided as well as images of most qualitative variables and of habits of selected species.

A revision of Coccothrinax, Hemithrinax, Leucothrinax, Thrinax, and Zombia was carried out based on morphological data taken from herbarium specimens. One thousand, two hundred and twenty-five specimens representing 69 preliminary species were measured for 15 quantitative variables and scored for 22 qualitative variables. Application of the Phylogenetic Species Concept resulted in recognition of 47 phylogenetic species—39 Coccothrinax, three Hemithrinax, one Leucothrinax, three Thrinax, and one Zombia. Nomenclature, descriptions, and distribution maps are provided for all species, as well as notes on distribution, habitat, taxonomy, and subspecific variation. Images of 32 species are provided.

A genus and species of palm from the Truong Son Range in Vietnam, Truongsonia lecongkietii, is described as new to science. Phylogenomic analysis strongly supports the placement of the new taxon in subfamily Arecoideae as sister to the African endemic tribe Podococceae, which comprises a single genus Podococcus. A new tribe Truongsonieae is also described to accommodate Truongsonia in the current phylogenetic classification of palms. Truongsonia is a dwarf, acaulescent, clump-forming palm bearing entire, bifid leaves with a fibre-like extension of the rachis through the sinus of the two lobes of the leaf. The interfoliar inflorescence is exserted on a long peduncle with 3­–4 tightly sheathing peduncular bracts and rachillae presented at the apex only. The ovary is triovulate-tricarpellate, but fruits are single-seeded. Truongsonia is Critically Endangered, with surveys locating only 10–15 plants in the wild. Swift conservation action is required to secure the future of this remarkable and phylogenetically isolated lineage of palms.

Five new species of Coccothrinax from Hispaniola are described and illustrated. A key is given to all species from the island.

A revision of Lanonia was carried out based on morphological data. Two hundred and eighteen herbarium specimens were examined and scored for 30 quantitative and 24 qualitative variables. Application of the Phylogenetic Species Concept to 13 preliminary species of Lanonia resulted in recognition of 19 phylogenetic species. Of these, six are recognized as new (L. honbaensis, L. honheoensis, L. kontumensis, L. montana, L. nuichuaensis, L. tenuisecta). Nomenclature, descriptions, and distribution maps are provided for all species. Images of the type specimens of all new species are provided as well as images of most qualitative variables.