The rare Baja California Sur endemic cactus Grusonia robertsii was originally hypothesized to be an intergeneric hybrid between G. invicta and Cylindropuntia alcahes subsp. alcahes but was described as a Grusonia due to its overall closer resemblance to G. invicta, except in the fruit. A more comprehensive analysis of the morphology and phylogenetic placement of G. robertsii based on plastid and nrDNA sequences has revealed that Rebman's original hypothesis was correct, and this taxon represents the first documented intergeneric hybrid between Cylindropuntia and Grusonia, with G. invicta as the maternal parent and C. alcahes subsp. alcahes as the paternal contributor. We here describe a new nothogenus, ×Cylindronia, and provide a new combination for the nothospecies ×Cylindronia robertsii comb. nov.

Smicrostigma warmwaterbergense is described from the summit of the Warmwaterberg on the Little Karoo of the Western Cape. It resembles S. viride in its habit and leaves but differs in that the flowers open during the day and close at night and the reproductive parts are fully visible when the flowers are open. The new species highlights the close links of Smicrostigma to Octopoma and Zeuktophyllum, which are also centered on the Little Karoo and share the leaves with a smooth surface, solitary, (sub-) sessile flowers and many-locular fruits.

Namaquanthus cephalophylloides is described from patches of quartz-gravel north of Kleinzee in Namaqualand in the Northern Cape. This new species shares with N. vanheerdei the thick, finger-shaped leaves and distinctly echinate seeds but differs from it by its dwarf habit, its gray leaves and downward-pointing fruit, which drop off once mature.

The nature of the relationship between millipedes and O. humifusa is still largely unknown. Here we present a report on observed interactions between invasive Opuntia humifusa with native millipede species. An observation of several individuals of a millipede species feeding on O. humifusa was made. The millipede activity was observed for 3.45 minutes and photographs were recorded. Damage to live plants parts was also noted. Over 27 millipedes were observed feeding on both decaying and live plant parts on a clump of Opuntia humifusa. This observation shows that invasive O. humifusa species are interacting with native species in multiple ways. We recommend a thorough survey of the O. humifusa populations and the surrounding areas to establish more details about this feeding behavior and whether indeed it may be furthering the spread of O. humifusa in the area.

Two new geophytic species of Peperomia subgenus Tildenia (Piperaceae) from Central Peru are described; (1) Peperomia pachyspadix is a new species from Huancavelica. It is phenotypically similar to P. andina from Cajamarca, but its leaves are not as thick and they lack the funnel shape and purple color of the abaxial side; it is also similar to P. wernerrauhii from Huánuco, but its leaves and tubers are larger. The new species can be distinguished from the abovementioned ones by the spadix, many times shorter and twice as thick. The seeds of P. andina, P. wernerrauhii and P. pachyspadix are similar in shape but the latter has the largest of all three. (2) Peperomia fundus-oculi is a new species with epigeous tuber discovered on the eastern Andean slopes of Ayacucho. Plants are morphologically like P. chutanka for its exposed and branched aerial tubers. Its leaves have a shape similar to this species but are not as succulent, they lack the purplish color of the abaxial side, and they have a characteristic pattern on its adaxial side, with a whitish iridescent spot in the center, with irregular margins, from where nerves emerge, giving the impression of the eye fundus, hence its name in Latin. Its anthers, ovaries, and fruits are also shorter than those of P. chutanka.

Opuntia is a genus of plants known as prickly pear cactus (nopales), with about 200 species, and is taxonomically complicated. The present study was focused on characterizing micromorphology and providing a phylogenetic hypothesis to place Opuntia setocarpa (described in 2017) in relation to other related species. Three individuals were characterized and collected in Neverías in the Sierra of Cacoma of the municipality Autlán de Navarro in Jalisco, Mexico. The micromorphology of spines, epidermis and stoma was characterized with scanning electron microscopy. The phylogenetic hypothesis was performed with maximum likelihood and Bayesian Inference including other Mexican species. Opuntia setocarpa is recovered as a supported species within Opuntia s.s.

Cereus tubiflorus Pfeiffer was described in 1837 on the basis of material without known wild origin, and a contemporaneous illustration was recently designated as neotype. In order to stabilize the application of the name (as Echinopsis tubiflora (Pfeiffer) K. Schumann in current classifications) for a taxon from the Andean foothills of N Argentina, we here designate an epitype. Further, we clarify the place of valid publication of the name.

Mode of reproduction in the genus Opuntia varies among species but often includes both vegetative and sexual reproduction, with the latter often facilitated by animal seed dispersal. In this multi-year study, we examined fruit and seed production and seed dispersal in the Mojave prickly pear (Opuntia phaeacantha) at two sites in the southwest Mojave Desert. Between 2015–2020 we counted fruits on randomly selected cactus patches, quantified fruit losses from those patches over time, collected fruits, and extracted and counted seeds. To assess seed dispersal, we collected fresh mammal pellets in belt transects at one site from 2016–2018; pellets were examined for Opuntia seeds. To assess animal fruit consumption and removal, we installed camera traps at one site. We baited selected patches with fruits and photographed animals that consumed or removed fruits. Fruit numbers varied widely among years and sites, although fruit production was not significantly correlated with climatic variables. Fruit losses were high at both sites, occurring more slowly in years of high fruit production. Seeds per fruit also varied with means ranging from 65 to 125 seeds. Rabbit and deer (Odocoileus hemionus) pellets were abundant at one site where we found 0.02 seeds per rabbit pellet but none in deer pellets. Camera traps baited with fruits revealed that they disappeared more quickly from patch edges than from patch interiors. Desert cottontails (Sylvilagus audubonii) and California jackrabbits (Lepus californicus) dominated photographs at patch edges while nearly all interior photographs were of white-tailed antelope squirrels (Ammospermophilus leucurus). In summary, although the number of seeds produced by O. phaeacantha is highly variable, the total number per site is high in some years, and fruits are consumed and seeds spread by animal dispersers.

We describe two new species of Ceropegia. Of these, Ceropegia pseudolugardiae Bruyns of sect. Phalaena H.Huber from Kenya and Tanzania has long been considered to belong to C. lugardiae N.E.Br. but has fibrous roots rather than the cluster of swollen, fusiform roots typical of C. lugardiae. This important feature has been much neglected, as the rootstock is absent from most herbarium specimens. Ceropegia pseudolugardiae is closely related to C. distincta N.E.Br. and C. zambesiaca Masinde & Meve, which all share the fibrous roots and differ in details of their flowers. The second species is C. lubangoensis Bruyns of sect. Laguncula H.Huber from Angola. This is distinguished from all others in this section by the considerably longer corolla-lobes.

Cactaceae-Angiospermae, of American origin, with worldwide naturalized distribution, includes promising species in economics and ecology; being a threatened group, it requires floristic studies that support conservation programs. This study estimates the number of cacti species present in Venezuela, and it contributes to the knowledge of the family in the country by reviewing herbaria specimens. The information came from the herbaria (FLASA, IUTAG, HERZU, HMBLUZ, MER, MY, MYF, PORT and VEN) of the country. It was transcribed into a database and organized by herbaria, genus and species, based on the labels of the exsiccatae and digital photographs of the specimens. In addition, foreign specialists were consulted to resolve doubts about the identity of some taxa. The botanical specimens reviewed totaled 2,293. In Venezuela the family Cactaceae is represented by 26 genera, 63 species, 13 synonymies, six subspecies, one variety and 17 genera with unidentified species, including wild, cultivated and endemic species. Opuntia stood out for its greatest number of species (15), followed by the genera Melocactus (10), Epiphyllum and Cereus (6), Selenicereus, Pilosocereus and Cylindropuntia (4), Hylocereus (3), Rhipsalis, Mammillaria, Pereskia and Leuenbergeria (2). The other genera presented one species. The information generated here can be an input for the design of strategies for conservation, selection, production or other uses of the species of this important botanical group.

Species can have broad altitudinal distributions and their characteristics may vary throughout distribution ranges. Ploidy level can vary along environmental gradients, such as altitudinal ones. However, the relationships between ploidy level and altitude may be diverse. The karyotype allows us to know the structural and quantitative characteristics of the chromosomal pairs and to relate these characteristics to the environment where the species occur. Species of the Cactaceae family can be found from sea level to 4500 m above sea level (asl). The greatest species richness is found in mountain areas, where species occupy wide altitudinal ranges. Gymnocalycium belongs to the subfamily Cactoideae; it is a genus endemic to southern South America and its main center of diversity is found in the mountain ranges of central and northern Argentina. The basic chromosome number for Cactaceae is x = 11, with polyploidy being the main existing variation. The aim of this work was to analyze cytogenetic variables in populations of four species of the genus Gymnocalycium (G. andreae, G. erinaceum, G. monvillei, and G. mostii) along their altitudinal distribution. Idiograms were constructed using HCl/Giemsa, CMA/DAPI fluorescent chromosomal banding and fluorescent in situ hybridization (FISH). The karyotypes of the analyzed populations of each species were symmetric and showed little variation in size and symmetry. All the populations of G. andreae, G. erinaceum and G. mostii were found to be diploid and had the greatest distribution; G. monvillei was found to be tetraploid in all the populations analyzed. CMA+/DAPIbands associated with secondary constrictions (NORs) were detected in all the populations of all the species. The cytogenetic characteristics of the studied species were constant along the altitudinal gradients, showing that they can occur at different altitudes without major cytogenetic modifications.

Two populations of Crassula subulata var. hispida, a variety previously recorded as being extinct, were discovered in the southern foothills of the Langeberg mountain range near the town of Ashton, in the Western Cape Province, South Africa. Characters of the living plant specimens are noted, and shown to agree with the type. Observations on the habitat and ecology of the plants are included; as is a suggested revised conservation status.