Flower colour polymorphism is one of the most attractive features in pollination studies. This article investigates the factors influencing the frequency of flower colour polymorphism in the Cuban cactus Leptocereus scopulophilus, where four flower morphs have been reported. We determined whether the colour of the tepals is a discrete variable and estimated morphs frequency in the population. To explain the frequencies of the flower morphs, we compared their dimensions. We also contrasted pollination success and flower florivory of the most frequent morphs. Leptocereus scopulophilus presents discrete values of tepal colour for all the morphs, including the albino morph reported in this study for the very first time. The light salmon morph is the most frequent in the population. This could be explained by the higher number of ovules and fruits it produces. Pollination in the species is confirmed to be exclusively nocturnal, and florivory is similar for the magenta and light salmon morphs.

Cylindropuntia imbricata (Haw.) F.M.Knuth (Cactaceae) is recorded as having become naturalised in south-central region of Zimbabwe. A description and illustrations of the species in Zimbabwe are provided. A key, based on vegetative characters which distinguish C. imbricata, C. fulgida (Engelm.) F.M.Knuth, C. leptocaulis (DC.) F.M.Knuth, C. pallida (Rose) F.M.Knuth and C. spinosior (Engelm.) F.M.Knuth, the five commonly grown or naturalised species in southern Africa, is included.

The animals that visit the flowers, pollinators and reproductive system of Opuntia joconostle were studied. The objectives of the work were to identify its floral visitors, to determine which are the most effective pollinators and to evaluate the importance of floral visitors in seed production. To determine the richness and frequency of the animal visitors, five study visits were made from May to June 2017, during which the animals that interacted with the flowers were recorded and collected for a period of thirty minutes for each hour between 10am and 16pm, after which the pollen grains were removed from the body of the collected specimens. For pollination efficiency, the pollen deposited by a specific pollinator in a single visit on the stigma and by self-pollination was counted and seed production from flowers where pollinator visits were avoided and another group with no restrictions were compared. A total of 2,261 floral visitors were recorded, belonging to four orders, eleven families, and twenty-seven species. Bees were the most abundant floral visitors with 98% of the records; the species with the highest number of visits was Apis mellifera with 90%, followed by Diadasia australis with 5%. A higher number of pollen grains per insect were recorded in D. australis than in A. mellifera, D. australis deposited more pollen per visit than A. mellifera and by self-pollination. Flowers that received pollinators produced significantly more seeds per fruit than flowers where visitors were prevented. O. joconostle flowers are used by many animals, however, the majority are bees, particularly two species: A. mellifera and D. australis, the former having a higher frequency of visitation. However, D. australis carries and deposits more pollen. Joconostle seems to have a mixed autogamy/ xenogamy crossing system, as self-pollination was recorded, although it negatively affected seed production. Thus, cross-pollination is important for the conservation of this species, increasing its chances of reproductive success by seed and preserving genetic diversity.

Echinocereus fitchii subsp. albertii (L.D.Benson) W.Blum & Mich.Lange, also known as Echinocereus reichenbachii var. albertii L.D.Benson, is a south Texas, USA endemic. The plant, commonly called black lace cactus, is listed as a federally endangered species in the United States. The objectives of this study are to 1 – survey populations of black lace cactus to determine current occurrence status, 2 – examine habitat and morphological features of black lace cactus across occurrences and 3 – examine the phylogeny of the E. reichenbachii-fitchii species complex to decipher the closest evolutionary relatives of black lace cactus. We photo-documented E. fitchii subsp. albertii individuals and confirmed extant populations in Kleberg, McMullen, and Refugio counties, Texas. Our study identified additional populations extending the sub-species' distributional range into Atascosa and La Salle counties, Texas. Flower colour of E. fitchii subsp. albertii is characteristic of the E. fitchii group. Central spines are absent to rare in E. fitchii subsp. albertii individuals in most populations, with only plants growing in the Kleberg Co. population commonly exhibiting central spines. We used genome skimming and assembly of nuclear ribosomal regions and nearly complete chloroplast genomes to examine phylogenetic relationships of fifteen taxa of Echinocereus. The most significant finding emerging from this phylogenetic study is that two distinct chloroplast genome lineages can be distinguished in E. fitchii subsp. albertii. One lineage includes individuals from Refugio Co. and McMullen Co. populations which are most closely related to E. reichenbachii subsp. caespitosus. The other lineage includes individuals from Atascosa and Kleberg Cos., which are most closely related to E. fitchii subsp. fitchii. These two lineages are not defined by geographic proximity.

The Cactaceae are a characteristic component of arid zones in the American continent. Some species are known to possess a seed bank, as a way to cope with environmental uncertainty, albeit seeds usually lose viability with time. Seed banks may respond with a constant, low germination proportion (delayed germination) or germination may depend on rainfall amount (predictive germination). On the other hand, several species of cacti usually co-occur in one locality. In the case of large, columnar species, we would expect competition as a corollary of their history of coexistence. We conducted two irrigation experiments (three watering levels: 40, 60, 80mm) to assess how seed viability in one columnar cactus is lost as years pass (three years), and to determine differences in germination/ early survival between two dominant columnar, sympatric cacti (Trichocereus atacamensis (Phil.) W.T.Marshall & T.M.Bock, T. tarijensis (Vaupel) Werderm.) from the arid puna. We predicted seeds from more recent years would have greater germination fractions and survival, and that the two columnar cactus species would show differences in their regeneration niche in order to decrease competition. We found a tendency for greater germination in younger seeds, and no effect of seed age on survival. Seeds from one of the species (T. atacamensis) had twice as many survivors as the other species (T. tarijensis). Both species showed a predictive response to water, having greater germination proportions with more irrigation. In conclusion, seed age affected germination, the columnar cactus species had a predictive germination, and showed differences in some aspects of their regeneration niche.

A total of twenty-one taxa of Cactaceae, including hybrids, are newly recognised or reevaluated for the area defined for the Cacti of Eastern Brazil, some being described for the first time. Other taxonomic changes are noted together with various range extensions and many of the plants concerned are illustrated.

The name ×Rhipsatiora astra Urano is published here for the artificial crossed intergeneric hybrid between genera Rhipsalis Gaertn and Hatiora Britton & Rose. This is the first report of an intergeneric hybrid for both R. cereuscula Haw. and H. salicornioides (Haw.) Britton & Rose in L.H.Bailey. The intergeneric hybrid has similarities to both parent species in terms of morphological characteristics. It could occur in a natural habitat.

Phemeranthus punae (R.E.Fr.) Eggli & Nyffeler (Montiaceae) is a perennial geophytic herb from the pre-Puna vegetation in the Andes of south-west Bolivia and north-west Argentina. Flowering plants have been observed for several seasons. Flowers are almost exclusively visited by at least three species of ants (Formicidae: likely Forelius pruinosus Roger, Linepithema sp. and Camponotus bruchi Forel). The ants move freely and rapidly on the plants and switch to neighbouring plants within less than five seconds. Pollen grains adhere to legs and bodies of the ants, which visit the flowers to feed on the nectar. The low stature of P. punae, its horizontally spreading to ascending inflorescences and the small flowers conform to the ant pollination syndrome characteristics formulated by Hickman (1974). It is concluded that the observed ants are the pollinators of the species in the study area.

The paper reports the discovery of the Southern African endemic Ruschia uncinata (L.) Schwantes (Aizoaceae) along the Mediterranean coastline on cliffs at Monastir in Tunisia (CE Tunisia, N-Africa). This is the first record of this species in this area. The population of R. uncinata, appears to be well-established and expanding. The large number of accompanying alien species suggests that the population of R. uncinata could have originated from dumped garden debris. Description of the morphology, distribution as well as habitat is provided.

Recent botanical surveys undertaken in central and northern Tunisia (North Africa) since 2014, mainly within coastal regions, yielded new records for non-native succulents (casual or naturalising aliens) of vascular plant species belonging to Asparagaceae sensu lato (Dracaena draco (L.) L. subsp. draco, Sansevieria hyacinthoides (L.) Druce, S. trifasciata Prain, Yucca aloifolia L. and Y. gloriosa L.). The reported taxa belong to three genera that represent first records for the vascular flora of Tunisia. Among these new taxa, Sansevieria hyacinthoides is first reported for North Africa and the Mediterranean area whereas Yucca aloifolia is here reported for the first time for North Africa. Distributions and morphological descriptions, as well as phenology and habitat, are given for each of these new records. Notes on their actual status and field photographs are provided.

Gasteria disticha var. marxii is described as a new variety from the lower foothills of the Witteberg and Klein Swartberg near Laingsburg, Western Cape, South Africa. It differs from other varieties mainly by its dwarf stature, an adaptation to its harsh habitat.

Bulbine sceletium (Asphodelaceae), only known from cliffs along the lower Great Fish and Mzimvubu Rivers, Eastern Cape Province, South Africa, is described. Its decumbent large greyish-green leaf rosettes are up to 300mm in diameter with persistent ovate to broadly ovate-acuminate leaves 300 × 140mm, drying from the tips into a thin papery striate persistent skeleton. The description of this taxon forms part of an extensive survey of cliff-dwelling succulent and bulbous-succulent taxa in South Africa and Namibia. A table is provided with a selection of characters of similar species of Bulbine in the Eastern Cape. A key is also provided to the cliff-dwelling Bulbine species of the summer rainfall parts of South Africa.

Aloe archeri, A. rendilliorum and A. tugenensis are very similar in morphology and leaf exudate chemistry but occupy separate geographical locations in northern Kenya. Here they are treated as subspecies of one species, for which A. archeri is the earliest name. Aloe tugenensis had already been reduced to subspecies rank, and the new combination A. archeri subsp. rendilliorum is proposed here. An identification key is provided. Together with three other species in eastern Africa they are possibly a local neoendemic group.

The nothospecies name Kalanchoe ×edwardii (Crassulaceae subfam. Kalanchooideae) was published for the hybrid between the arborescent K. beharensis and the shrubby K. tomentosa, two Malagasy species. Two well-known cultivars, K. ×edwardii ‘Fang’ and K. ×edwardii ‘Rose Leaf’, or simply K. ‘Fang’ and K. ‘Rose Leaf’, have been selected and named from K. ×edwardii. To facilitate distinguishing between these two cultivars, differences between them are tabulated and discussed. A general discussion of aspects of interspecific hybridisation in Kalanchoe is provided.

In terms of number of taxa accepted at present – about 180 – Kalanchoe (Crassulaceae subfam. Kalanchooideae) is the third largest genus recognised in the family. Madagascar is home to more than one third of the recognised taxa with the rest spread across Africa, and the Near, Middle, and Far East. In terms of growth form (trees, various types of shrubs, herbs, epiphytes; all leaf succulents), Madagascar also harbours the greatest diversity found in the genus. Several Malagasy species of Kalanchoe have attracted significant research interest from horticultural, (eco-)physiological and invasions biological perspectives. However, the species that occur beyond Madagascar have not been studied to the same degree. This review provides a synthesis of field observations made over several decades, especially in southern Africa, and of available information on several aspects of kalanchoe biology and ecology assembled from a wide range of sources. Such synthesised knowledge is important for, inter alia, informing conservation management strategies for wild kalanchoe populations, as well as more widely for the grassland and savanna and, to a lesser degree, forest and thicket, habitats in which the species mostly occur.

Willem Frederik Reinier Suringar and Jan Valckenier Suringar between them named a large number of Melocactus species in the middle of the nineteenth and start of the twentieth century. All of them subsequently have been considered to be synonyms of M. macracanthos, M. stramineus, M. curvispinus subsp. koolwijkianus or M. ×bozsingianus. W. Suringar visited the West Indies, Suriname, Guyana and Trinidad, collecting plants. In Curaçao he took special note of melocacti. Through a study of their descriptions, herbarium material and published images, several new synonyms of their taxa are designated in this paper. One Suringar Melocactus, M. stramineus, recently demoted to a subspecies of macracanthos, is reinstated as a good species. An assessment of the work of the Suringars is made. It is noted that, in spite of reservations about their species concept, the Suringar taxa are valid and have to be considered in any taxonomic study of melocacti from the West Indies.

The Voynich Codex is one of the greatest bibliographic mysteries of our time. Its origin and interpretations have puzzled academics for decades. The botanical illustrations are equally enigmatic and have defied accurate identification Recently, Tucker & Janick (2019) have produced a plausible list of identified plants, some of which are succulent. This paper discusses the succulent species identified by Tucker & Janick in the context of identifications by others and concludes that, although these authors have contributed to the debate, their conclusions still lack certainty.

The origins of Glasgow Botanic Garden can be found in the city's college ‘physic’ garden in 1704. A new garden, the Royal Botanic Institute of Glasgow replaced it in 1818 at Sandyford in the city. Thomas Hopkirk’s collection formed the basis of the garden. When a larger garden was needed, the Glasgow Botanic Garden was set up in its present location in 1840. William Jackson Hooker made a significant contribution to the development of the garden in the first half of the nineteenth century. As editor of Curtis’s Botanical Magazine for thirty-six years and Director of Kew Gardens, he was a major figure in the field of botanical science. This article details the history of the gardens with particular reference to Hooker. It also reflects on the cacti and other succulents in the early gardens and details lists produced between 1813 and 1825.

Palmer's Culture des Cactées was published in Paris in 1867 during the first cactus cornucopia in mid-nineteenth-century France. The contents of the book are summarised and its illustrations are discussed in detail. For its time, it is well illustrated with thirty-three engravings, for which sources of just ten have been identified. Original sources for six of Palmer's engravings are illustrated here for comparison. Britton & Rose (1919–1923) cited twelve of the engravings, indicating their historical significance. As a growers' guide the book compares favourably with those published in 1845 and 1868 by Charles Lemaire, Palmer's contemporary and leading light in the French cactus scene at that time. The rarity of Palmer's book is indicated by the fact that only seventeen copies have been located, details of which are tabulated.