Four new taxa and nine new combinations are required for forthcoming floristic works by the authors. The new taxa are Centaurium tenuiflorum (Hoffmanns. & Link) Fritsch subsp. anglicum T.C.G.Rich & McVeigh, subsp. nov.; Centaurium × klattii P.Fourn. ex T.C.G.Rich, hyb. nov.; Centaurium × ubsdellii T.C.G.Rich, hyb. nov.; and Gentianella amarella (L.) Börner subsp. occidentalis T.C.G.Rich & McVeigh, subsp. nov. The new combinations are Centaurium erythraea Rafn var. latifolium (Sm.) T.C.G.Rich, comb. et stat. nov.; Gentianella amarella (L.) Börner subsp. anglica (Pugsley) T.C.G.Rich & McVeigh, comb. et stat. nov.; Aria parviloba (T.C.G.Rich) Sennikov & Kurtto, comb. nov.; Cotula sessilis (Ruiz & Pav.) Stace, comb. nov.; Elymus × drucei (Stace) Stace, comb. nov.; Elymus repens (L.) Gould f. aristatus (Schumach.) Stace, comb. nov.; Elymus athericus (Link) Kerguélen f. setigerus (Dumort.) Stace, comb. nov.; Ulmus minor Mill. subsp. cornubiensis (Weston) Stace, comb. et stat. nov.; and Dysphania ambrosioides (L.) Mosyakin & Clemants var. anthelmintica (L.) Stace, comb. nov.

Cerrado vegetation is the main formation covering c.60% of the land surface of Maranhão, Brazil, with cerradão being the dominant physiognomy. To characterise the cerrado flora in Maranhão, 12 localities were selected across its distribution in the northeastern, central, southern and southeastern regions of the state. A total of 150 angiosperm species were identified, distributed across 105 genera and 43 families. Twelve are new occurrences in Maranhão, and of these, four are also new records for Northeast Brazil. Two distinct floristic regions were recognised: the cerrados of the northeastern and central regions, and the cerrados of the southern region. Three subgroups were recognised in the southern region: cerrados of the highest altitudes, medium-altitude cerrados and cerrados of variable altitudes. Floristic comparisons with the Brazilian cerrados suggest that the medium-altitude southern cerrados of Maranhão are similar to those of the central region of Brazil, whereas the northeastern, central and southern highest-altitude regions form a distinct floristic group.

A new combination in Vachellia is published for Acacia pennivenia. A summation of the current state of knowledge of this Socotran endemic species is presented, including a morphological description, a distribution map and an updated conservation assessment. Colour photographs and a black-and-white line drawing are presented.

For 185 years, the genus Eumachia (Rubiaceae) was considered to include one species from Tonga. Since 2015, 94 more names have been added to it, expanding Eumachia into a pantropical genus of shrubby plants, most of whose members were originally described in Psychotria. Four Psychotria species from Southeast Asia that were identified as potentially belonging in Margaritopsis (now a synonym of Eumachia) have not yet had combinations made in Eumachia. They are considered here, and new combinations are made for Psychotria extensa Miq., P. montana Blume and P. rostrata Blume. The fourth name, Psychotria expansa Blume, is considered a synonym. The identities of Chassalia sangiana Miq. and Psychotria rhodocarpa Teijsm. & Binn. are also discussed. Lectotypes are designated for several names.

Three new species of the Neotropical genus Barbacenia (Velloziaceae, Pandanales) from Tocantins, Brazil, are described and illustrated, based on morphology and leaf anatomy. The known species richness of the genus is mapped within the countries of South America and the states of Brazil.

To date, there are very few sequence data for Cyperaceae from mainland Southeast Asia. The aim of the present study was to contribute nuclear ribosomal internal transcribed spacer (ITS) sequences of selected species of Cambodian Cyperaceae to the overall phylogeny of the family. We generated ITS sequences of 38 accessions representing 26 species from Cambodia and used these sequences for phylogenetic analysis together with similar sequences from the National Center for Biotechnology Information GenBank. Our results corroborate recent phylogenetic work in the family and largely confirm established tribal relationships. The backbone of the phylogenetic tree of species-rich genera that have undergone rapid radiations is often weakly resolved (e.g. in Fimbristylis and in the C4 clade of Cyperus). Cryptic variation was revealed in the taxonomically difficult group of Fimbristylis dichotoma, with samples of this taxon appearing in two distinct clades within Fimbristylis. Further addition of geographically spread accessions of taxa will improve our understanding of the complex biogeographical history of the genera in the family. Eleocharis koyamae Tremetsb. & D.A.Simpson is proposed as a new name for E. macrorrhiza T. Koyama.

The new species Aeschynanthus scottii D.J.Middleton & H.J.Atkins from Vietnam is described.

Systematic data collection for direct statistical analysis of biodiversity trends tends to be focused on charismatic fauna and flora such as birds or vascular plants. When subsequently applied by conservation agencies in summary metrics tracking habitat and species protection, these patterns in biodiversity loss or gain can fail to capture outcomes for groups that have a prominent importance in habitat composition, diversity and ecological function, such as algae, bryophytes, lichens and other fungi. Such species are primarily recorded on an ad hoc basis by taxonomic specialists, yielding noisy data that present problems in robustly identifying trends. This study explored the use of ad hoc field-recorded data as a potential source of biodiversity information, by comparing the pattern of recording for carefully selected indicator species with those for benchmark or control species as a proxy for recording effort. Focusing on Scotland’s internationally important epiphytic lichens, and especially ‘old-growth’ indicator species, British Lichen Society data revealed a decline in the extent of these species in Scotland, relative to recording effort, over a period of five decades. A recent slowing in the rate of decline is observed but remains to be confirmed. The long-term decline is consistent with the effect of land use intensification, resulting in small and isolated populations that are vulnerable to extinction debt. We caution that remedial protection and monitoring for such populations remains vital as a complement to Scotland’s larger scale ambition for increased woodland extent and connectivity.

As part of ongoing molecular phylogenetic work on the large Gesneriaceae genus Cyrtandra, new insights into the taxonomy and relationships of the Cyrtandra of Japan, Taiwan and Batan Island in the northern Philippines have emerged. Cyrtandra umbellifera is confirmed as a species with a distribution that includes both Taiwan and Batan Island. Cyrtandra yaeyamae is found to be distinct from the widespread C. cumingii, with a distribution that includes both the Ryukyu Islands in Japan and Batan Island.

Towards a comprehensive revision of Gesneriaceae in Sri Lanka, 12 names are here typified, of which 11 are lectotypifications, including one second-step lectotypification, and the other is a neotypification.

Based on studies of types and recent collections, the number of species of Etlingera Giseke in the Philippines is doubled from eight to 16. Three species (Etlingera alba, E. brevilabrum and E. sessilanthera) are reported here for the first time, E. pandanicarpa is synonymised with the Bornean E. fimbriobracteata, and four new combinations (E. bulusanensis, E. linearifolia, E. pubimarginata and E. subviridis) and one new name (E. pilosa) are published here. Nine lectotypifications are proposed, of which three represent second-step designations. About two-thirds of the species are currently thought to be endemic, but future fieldwork is likely to result in more species of Etlingera in the Philippines, either endemic or as new records from neighbouring islands.

Didymocarpus middletonii Souvann., Soulad. & Tagane, a new species of Gesneriaceae from Nam Kading National Protected Area, is described and illustrated. The new species is morphologically similar to Didymocarpus brevicalyx, D. formosus and D. puhoatensis but distinguished from the three by its fewer-flowered inflorescence, longer pedicel, and urceolate and multicellular eglandular hairy calyx. Based on the latest IUCN criteria, Didymocarpus middletonii is proposed to be Critically Endangered (CR). Our record of Didymocarpus represents a new genus record for the flora of Laos.

Englerophytum and Synsepalum are two closely related genera of trees and shrubs from the African tropics. Previous molecular studies have shown that these genera collectively form a clade within the subfamily Chrysophylloideae (Sapotaceae). However, little is known about the inter-relationships of the taxa within the Englerophytum–Synsepalum clade. In this study, nuclear ribosomal DNA and plastid trnH–psbA sequences were used to estimate the phylogeny within the clade. Results indicate that the clade consists of six major lineages, two composed solely of taxa from the genus Englerophytum and four composed of taxa from the genus Synsepalum. Each lineage can be distinguished by suites of vegetative and floral characters. Leaf venation patterns, calyx fusion, style length and staminodal structure were among the most useful characters for distinguishing clades. Some of the subclades within the Englerophytum–Synsepalum clade were also found to closely fit descriptions of former genera, most of which were described by Aubréville, that have since been placed in synonymy with Englerophytum and Synsepalum. The clade with the type species of Englerophytum also contains the type species of the genera Wildemaniodoxa and Zeyherella, which are confirmed as synonyms.

A new species of Lavandula (Lamiaceae) is described from the Western Hajar Mountains of Oman. The species is fully described and illustrated. Habitat details and an assessment of its conservation status are provided.

Salvia daiguii Y.K.Wei & Y.B.Huang, a new species from China, is described. Salvia daiguii belongs to Salvia subg. Glutinaria (Raf.) G.X.Hu, C.L.Xiang & B.T.Drew, sect. Sobiso (Raf.) G.X.Hu, A.Takano & B.T.Drew, and is distinguished from morphologically similar species by differences in its habit, leaves, inflorescences and flowers. It has a narrow distribution in a karst region of Yongding District, Hunan Province, central China. A key to the Chinese species of section Sobiso is also presented.

Rigiolepis and Vaccinium of Borneo are revised, and their characteristics are discussed. Brief comments on distinguishing Vaccinium and Rigiolepis from related genera in the Ericaceae are made. Vaccinium sect. Bracteata is now considered the only section of Vaccinium occurring in Borneo. The chief reason for reinstating Rigiolepis as a genus is the distinctive 10-locular ovary whose structure has been overlooked in recent studies, while the supporting characters of multiple axillary flower buds, flower size, anther shape and fruit colour provide for easy recognition. New keys are provided to all 42 species, and all accepted taxa are described. Ten taxa are new to science and 17 new combinations are made. An addendum gives the combinations to be used for the two species of Rigiolepis presently known to occur outside Borneo.

Two new species of Malpighiaceae are proposed: Hiraea costaricensis C.E.Anderson and H. polyantha C.E.Anderson. Hiraea costaricensis is characterised by the presence of basifixed hairs on the stems and leaves; H. polyantha, of Colombia, is distinctive in its large inflorescences, composed of c.100 flowers. Collections of the novelties had been associated with Hiraea smilacina Standl., a species that traditionally had been thought conspecific with H. quapara (Aubl.) Sprague; they are immediately separated by their fruits. In Hiraea smilacina the schizocarps break into three butterfly-shaped samaras, as is typical for the genus. The fruit of Hiraea quapara is spherical, composed of three mericarps covered by a network of reduced winglets. Hiraea smilacina is found from southern Mexico through Central America, except El Salvador and Nicaragua, and has been collected also in Colombia and Ecuador. Hiraea quapara is known mainly from French Guiana, with one collection from adjacent Suriname and two from Amapá, Brazil. All taxa are fully described and illustrated.

Viscum sahyadricum (Santalaceae) from the Western Ghats of India is here described as a new species with description, illustrations and notes.