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Acanthochlamys P.C. Kao is a Chinese endemic monotypic genus, whereas Xerophyta Juss. is a genus endemic to Africa mainland, Arabian Peninsula and Madagascar with ca.70 species. In this recent study, the complete chloroplast genome of Acanthochlamys bracteata was sequenced and its genome structure compared with two African Xerophyta species (Xerophyta spekei and Xerophyta viscosa) present in the NCBI database. The genomes showed a quadripartite structure with their sizes ranging from 153,843 bp to 155,498 bp, having large single-copy (LSC) and small single-copy (SSC) regions divided by a pair of inverted repeats (IR regions). The total number of genes found in A. bracteata , X. spekei and X. viscosa cp genomes are 129, 130, and 132, respectively. About 50, 29, 28 palindromic, forward and reverse repeats and 90, 59, 53 simple sequence repeats (SSRs) were found in the A. bracteata , X. spekei , and X. viscosa cp genome, respectively. Nucleotide diversity analysis in all species was 0.03501, Ka/Ks ratio average score was calculated to be 0.26, and intergeneric K2P value within the Order Pandanales was averaged to be 0.0831. Genomic characterization was undertaken by comparing the genomes of the three species of Velloziaceae and it revealed that the coding regions were more conserved than the non-coding regions. However, key variations were noted mostly at the junctions of IRs/SSC regions. Phylogenetic analysis suggests that A. bracteata species has a closer genetic relationship to the genus Xerophyta. The present study reveals the complete chloroplast genome of A. bracteata and gives a genomic comparative analysis with the African species of Xerophyta. Thus, can be useful in developing DNA markers for use in the study of genetic variabilities and evolutionary studies in Velloziaceae. [ABSTRACT FROM AUTHOR]

Croton kinondoensis, a new species from Kenya, is described and illustrated here with photographs. It is found in the sacred Kaya Kinondo Forest, one of the last remaining coastal forests patches in Kenya. Its morphology and systematic position based on ITS and trnL-F DNA sequence data clearly place it within the Adenophorus Group of Croton, a clade of ca. 15 species otherwise known only from Madagascar and the Comoros Archipelago. Its closest affinities appear to lie with Croton mayottae, from the island of Mayotte, and C. menabeensis, from northwestern Madagascar. This new species likely represents an independent dispersal of Croton from Madagascar to mainland Africa. [ABSTRACT FROM AUTHOR]

The baobab trees (genus Adansonia) have attracted tremendous attention because of their striking shape and distinctive relationships with fauna 1 . These spectacular trees have also influenced human culture, inspiring innumerable arts, folklore and traditions. Here we sequenced genomes of all eight extant baobab species and argue that Madagascar should be considered the centre of origin for the extant lineages, a key issue in their evolutionary history 2,3 . Integrated genomic and ecological analyses revealed the reticulate evolution of baobabs, which eventually led to the species diversity seen today. Past population dynamics of Malagasy baobabs may have been influenced by both interspecific competition and the geological history of the island, especially changes in local sea levels. We propose that further attention should be paid to the conservation status of Malagasy baobabs, especially of Adansonia suarezensis and Adansonia grandidieri, and that intensive monitoring of populations of Adansonia za is required, given its propensity for negatively impacting the critically endangered Adansonia perrieri., (© 2024. The Author(s).)