A biographic summary of the research of Dr Graham Charles George Argent (born 15 May 1941, died 24 April 2019) is presented, summarising his research career. Expedition information, including dates, collection number series and the names of collaborators, is given, as is a list of his publications, annotated with taxonomic decisions and the names of new species described within them.

The species of Jasminum Tourn. ex L. (Oleaceae) in Peninsular Malaysia are revised. Eighteen species are recognised, of which eight are endemic. Five of these species have been recorded from Singapore. A key to species is provided, all names are typified, and all species are described. Conservation assessments are given for all species in Peninsular Malaysia. One species is Extinct in Peninsular Malaysia, eleven are Endangered and one is Data Deficient. Jasminum shahii Kiew is described as a new species. In Singapore, two species are certainly Extinct.

Recent botanical explorations in the province of Palawan, Philippines, have resulted in the discovery of two new ginger species, namely Boesenbergia eburnea Docot and Boesenbergia leonardocoi Funak. & Docot, which are described and illustrated here, including information on their distribution, habitat, phenology, ecology and conservation status. Additionally, a key to Boesenbergia species in the Philippines is provided.

Curcuma cinnabarina and C. eburnea (Curcuma subg. Ecomatae, Zingiberaceae), two new species from Thailand, are described and illustrated here. They are compared with the morphologically closest species Curcuma rubrobracteata and C. pierreana, respectively. Detailed descriptions, colour plates, and information on their distribution, ecology, phenology and uses are also provided. Preliminary IUCN conservation assessments of these species are proposed.

Memecylon nervosum Vadhyar, J.H.F.Benj. & Sujana, a new species of Melastomataceae from the Kanyakumari Wildlife Sanctuary, Western Ghats, India, is described and illustrated. It is compared with the closely allied Memecylon heyneanum Benth. and Memecylon jambosioides Wight.

Sixty new or updated records of plants species are reported from the Sultanate of Oman, as a result of fieldwork and research undertaken. Five taxa represent new records for Arabia, twenty-seven taxa are new records for Oman, and twenty-eight records represent an extended distribution within Oman. Some previously doubtful records are confirmed. Brief comments are given on the phytogeography, taxonomy and ecology of the taxa. Most new records have been collected in mountainous areas, either in southern Oman or in northern Oman, mainly in areas that previously were botanically poorly known.

Six new species of Vaccinium, identified as new to science by the late George Argent while compiling a revision of Vaccinium sect. Orianthe for New Guinea, are described and illustrations provided.

The species of Gagnepainia K.Schum. and Hemiorchis Kurz are revised throughout their ranges. These genera are shown with evidence from morphological and molecular studies to be distinct, although closely related to each other. Two species of Gagnepainia and three of Hemiorchis are recognised. A key to the genera of Globbeae and keys to the species of Gagnepainia and Hemiorchis are given, all names are typified and descriptions are provided. Conservation assessments of all taxa are proposed.

Nine new species in four genera of Neotropical Malpighiaceae are described and illustrated: Banisteriopsis rostrata W.R.Anderson (Brazil: Minas Gerais), Bunchosia andina W.R.Anderson (Colombia: Antioquia, Caldas, Nariño, Putomayo, Quindío, Tolima, Valle; Ecuador: Azuay, Napo, Pichincha, Tungurahua); Bunchosia parrae W.R.Anderson (Peru: Loreto, San Martín, Ucayali), Bunchosia phaeocarpa W.R.Anderson (Ecuador: Napo, Orellana, Pastaza, Sucumbíos; Peru: Loreto), Byrsonima anisophylla W.R.Anderson (Brazil: Bahia), Byrsonima cardenasii W.R.Anderson (Colombia: Antioquia, Nariño, Riseralda, Santander, Valle del Cauca), Byrsonima goiana W.R.Anderson (Brazil: Goiás), Byrsonima nana W.R.Anderson (Colombia: Meta) and Tetrapterys catarinensis W.R.Anderson (Brazil: Santa Catarina).

National vegetation classification (NVC) has been widely applied as a framework for mapping and conserving plant species and community types. However, a limited availability of expertise has prevented NVCs from being developed and used in cryptogam-dominated systems, such as for temperate and boreal epiphyte communities. This study simplified a recent systematically sampled NVC, trialled for epiphyte communities in Scotland, by reducing the original list of 82 community indicators to 34 easily recognisable species (lichens, mosses and liverworts). These were subsequently sampled from woodland sites positioned in Scotland’s temperate rain forest zone. Sites were positioned among localities in less intensively managed landscapes (northwest Scotland) through to peri-urban environments (southern Scotland), grouping sites for each locality based on a contrast in woodland temporal continuity (ancient or recent). The richness and diversity of epiphyte community indicators were compared with easily measured variables reflecting stand heterogeneity or ecological stability, and woodland temporal continuity, with air pollution as a covariable. Richness and diversity were significantly explained by the ecological stability of woodland stands, heterogeneity of the light environment, and nitrogen pollution. This demonstrates a tool that can be deployed by the non-specialist, with appropriate training, to quantify the condition of a woodland stand through consequences for its epiphytes in globally important temperate rain forest. The pattern of richness and diversity was consistent with the co-occurrence of particular indicator species, which represent the range of epiphyte community types supported by a woodland.

A new species, Scaphochlamys longipedunculata (Zingiberaceae), is described and illustrated here. It is similar to Scaphochlamys grandis but differs in having 1- or 2-leaved shoots (versus shoots with 5 or more leaves) and peduncle length c.17 cm (versus peduncle length c.7 cm).