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Abstract Premise A probe set was previously designed to target 384 nuclear loci in the Melastomataceae family; however, when trying to use it, we encountered several practical and conceptual problems, such as the presence of sequences in reverse complement, intronic regions with stop codons, and other issues. This raised concerns regarding the use of this probe set for sequence recovery in Melastomataceae. Methods In order to correct these issues, we cleaned the Melastomataceae probe set, extended it with additional sequences, and compared its performance with the original version. Results The final probe set targets 396 putative nuclear loci represented by 6009 template sequences. The probe set has been made available, along with details on the cleaning process, for reproducibility. We show that the new probe set performs better than the original version in terms of sequence recovery. Discussion This updated, extended, and cleaned probe set will improve the availability of phylogenomic resources across the Melastomataceae family. It is fully compatible with sequence recovery and extraction pipelines. The cleaning process can also be applied to any plant‐targeting probe set that would need to be cleaned or updated if new genomic resources for the targeted taxa become available.

Monodoreae (Annonaceae) is a tribe composed of 11 genera and 90 species restricted to the tropical African rain forests. All the genera are taxonomically well circumscribed except the species rich genera Uvariodendron and Uvariopsis which lack a recent taxonomic revision. Here, we used a robust phylogenomic approach, including all the 90 currently accepted species, with several specimens per species, and based on more than 300 Annonaceae-specific nuclear genes, to infer the phylogenetic tree of the Monodoreae and test the limits between the genera and species. We recover all the genera as monophyletic, except the genus Uvariopsis for which the species Uvariopsis tripetala falls outside this clade. We thus reinstate the monotypic genus Dennettia for its single species Dennettia tripetala. We also erect a new tribe, Ophrypetaleae trib. nov., to accommodate the genera Ophrypetalum and Sanrafaelia, as we recover them excluded from the Monodoreae tribe with good support. Below the genus level, the genera Isolona, Monodora, Uvariastrum, Uvariodendron and Uvariopsis show weakly supported nodes and phylogenetic conflicts, suggesting that population level processes of evolution might occur in these clades. Our results also support, at the molecular level, the description of several new species of Uvariodendron and Uvariopsis, as well as several new synonymies. Finally, we present a taxonomic revision of the genera Dennettia, Uvariodendron and Uvariopsis, which contain one, 18 and 17 species respectively. We provide a key to the 11 genera of the Monodoraeae and describe four new species to science: Uvariodendron kimbozaense Dagallier & Couvreur, sp. nov., Uvariodendron mossambicense Robson ex Dagallier & Couvreur, sp. nov., Uvariodendron pilosicarpum Dagallier & Couvreur, sp. nov. and Uvariopsis oligocarpa Dagallier & Couvreur, sp. nov., and provide provisional descriptions of three putatively new species. We also present lectotypifications and nomenclatural changes implying synonymies and new combinations (Uvariodendron citriodorum (Le Thomas) Dagallier & Couvreur, comb. et stat. nov., Uvariodendron fuscum var. magnificum (Verdc.) Dagallier & Couvreur, comb. et stat. nov., Uvariopsis congensis var. angustifolia Dagallier & Couvreur, var. nov., Uvariopsis guineensis var. globiflora (Keay) Dagallier & Couvreur, comb. et stat. nov., and Uvariopsis solheidii var. letestui (Pellegr.) Dagallier & Couvreur, comb. et stat. nov.).

Abstract The Checklist of the Vascular Plants of the Republic of Guinea (CVPRG) is a specimen-based, expert-validated knowledge product, which provides a concise synthesis and overview of current knowledge on 3901 vascular plant species documented from Guinea (Conakry), West Africa, including their accepted names and synonyms, as well as their distribution and status within Guinea (indigenous or introduced, endemic or not). The CVPRG is generated automatically from the Guinea Collections Database and the Guinea Names Backbone Database, both developed and maintained at the Royal Botanic Gardens, Kew, in collaboration with the staff of the National Herbarium of Guinea. A total of 3505 indigenous vascular plant species are reported of which 3328 are flowering plants (angiosperms); this represents a 26% increase in known indigenous angiosperms since the last floristic overview. Intended as a reference for scientists documenting the diversity and distribution of the Guinea flora, the CVPRG will also inform those seeking to safeguard the rich plant diversity of Guinea and the societal, ecological and economic benefits accruing from these biological resources.

Annonaceae is a major pantropical family with 113 genera and about 2550 species. Cameroon is one of the most biodiverse countries in Africa but its flora remains incompletely known. In this volume of the Flora of Cameroon, we describe 166 native taxa representing 163 species in 28 native genera within the family Annonaceae. A total of 22 species (about 13%) are endemic to the country. We provide keys to all native genera, species, and infraspecific taxa. For each species a detailed morphological description and a map of its distribution in Cameroon are provided. Distribution maps and diversity analyses are based on a taxonomically verified database of 2073 collections. Across Africa, Cameroon is a center of diversity for Annonaceae harboring one of the highest numbers of species and genera. For example, Cameroon harbors the highest number of African species for the only pantropical genus of Annonaceae, Xylopia. Annonaceae are found across all 10 administrative regions of Cameroon but diversity is concentrated within the tropical rain forest areas situated in the south and South-West. The areas around Bipindi and Mount Cameroon show the highest levels of diversity, but this is correlated with collection effort. Line drawings and/or photographs accompany most species. One species new to science Uvariopsis etugeana Dagallier & Couvreur sp. nov. is described. We also undertake a number of nomenclatural changes such as lectotypifications, six new synonymies and two new combinations ( Uvaria anisotricha (Le Thomas) Couvreur, comb. nov.; Uvariodendron fuscum var. giganteum (Engl.) Dagallier & Couvreur, comb. nov.).

Background and Aims Throughout the Cenozoic, Africa underwent several climatic and geological changes impacting the evolution of tropical rain forests (TRFs). African TRFs are thought to have extended from east to west in a 'pan-African' TRF, followed by several events of fragmentation during drier climate periods. During the Miocene, climate cooling and mountain uplift led to the aridification of tropical Africa and open habitats expanded at the expense of TRFs, which probably experienced local extinctions. However, in plants, these drivers were previously inferred using limited taxonomic and molecular data. Here, we tested the impact of climate and geological changes on diversification within the diverse clade Monodoreae (Annonaceae) composed of 90 tree species restricted to African TRFs. Methods We reconstructed a near-complete phylogenetic tree, based on 32 nuclear genes, and dated using relaxed clocks and fossil calibrations in a Bayesian framework. We inferred the biogeographical history and the diversification dynamics of the clade using multiple birth–death models. Key Results Monodoreae originated in East African TRFs ~25 million years ago (Ma) and expanded toward Central Africa during the Miocene. We inferred range contractions during the middle Miocene and document important connections between East and West African TRFs after 15–13 Ma. Our results indicated a sudden extinction event during the late Miocene, followed by an increase in speciation rates. Birth–death models suggested that African elevation change (orogeny) is positively linked to speciation in this clade. Conclusion East Africa is inferred as an important source of Monodoreae species, and possibly for African plant diversity in general. Our results support a 'sequential scenario of diversification' in which increased aridification triggered extinction of TRF species in Monodoreae. This was quickly followed by fragmentation of rain forests, subsequently enhancing lagged speciation resulting from vicariance and improved climate conditions. In contrast to previous ideas, the uplift of East Africa is shown to have played a positive role in Monodoreae diversification. [ABSTRACT FROM AUTHOR]

Background The Ebo Forest area is a highly threatened centre of diversity in the Littoral Region of Cameroon, globally important for conservation with many threatened species including 68 threatened species of plant, yet not formally protected. The tropical African evergreen forest tree genus Uvariopsis Engl. & Diels (Annonaceae) is characterised by unisexual, usually cauliflorous flowers with a uniseriate corolla of four petals, and two sepals. Cameroon is the centre of diversity of the genus with 14 of the 19 known species. Methods The herbarium collection MacKinnon 51 from Ebo is hypothesized to represent a new species to science of Uvariopsis. This hypothesis is tested by the study of herbarium specimens from a number of herbaria known to hold important collections from Cameroon and surrounding countries. Results We test the hypothesis that MacKinnon 51 represents a new species to science, using the most recent dichotomous identification key, and comparing it morphologically with reference material of all known species of the genus. We make a detailed comparative morphological study focussing on three other Cameroonian species, Uvariopsis solheidii, U. korupensis and the sympatric U. submontana. In the context of a review of the pollination biology of Uvariopsis, we speculate that in a genus otherwise with species with dull, flesh-coloured (pink, red to brown) flowers pollinated (where known) by diptera, orthoptera and blattodea (flies, crickets and cockroaches), the glossy, pale yellow-green flowers of Uvariopsis dicaprio, with additional traits unique in the genus, may be pollinated by nocturnal moths. Based on MacKinnon 51, we formally name Uvariopsis dicaprio Cheek & Gosline (Annonaceae) as new to science, and we describe, and illustrate, and map it. Restricted so far to a single site in evergreen forest in the Ebo Forest, Littoral Region, Cameroon, Uvariopsis dicaprio is provisionally assessed as Critically Endangered using the IUCN, 2012 standard because the forest habitat of this species remains unprotected, and there exist imminent threats of logging and conversion to plantations. Discussion We show that the highest density of species of the genus (12), and of narrow endemics (5), is found in the Cross-Sanaga Interval of SE Nigeria and Western Cameroon. A revised key to the 14 Cameroonian species of Uvariopsis is presented. We review the other seven narrowly endemic and threatened species unique to the Ebo forest of Cameroon and discuss the phytogeographic affinities of the area. Conclusions Uvariopsis dicaprio adds to the growing list of species threatened with extinction at Ebo Forest due to current anthropogenic pressures.

Monodoreae (Annonaceae) is a tribe composed of 11 genera and 90 species restricted to the tropical African rain forests. All the genera are taxonomically well circumscribed except the species rich genera Uvariodendron and Uvariopsis which lack a recent taxonomic revision. Here, we used a robust phylogenomic approach, including all the 90 currently accepted species, with several specimens per species, and based on more than 300 Annonaceae-specific nuclear genes, to infer the phylogenetic tree of the Monodoreae and test the limits between the genera and species. We recover all the genera as monophyletic, except the genus Uvariopsis for which the species Uvariopsis tripetala falls outside this clade. We thus reinstate the monotypic genus Dennettia for its single species Dennettia tripetala. We also erect a new tribe, Ophrypetaleae trib. nov., to accommodate the genera Ophrypetalum and Sanrafaelia, as we recover them excluded from the Monodoreae tribe with good support. Below the genus level, the genera Isolona, Monodora, Uvariastrum, Uvariodendron and Uvariopsis show weakly supported nodes and phylogenetic conflicts, suggesting that population level processes of evolution might occur in these clades. Our results also support, at the molecular level, the description of several new species of Uvariodendron and Uvariopsis, as well as several new synonymies. Finally, we present a taxonomic revision of the genera Dennettia, Uvariodendron and Uvariopsis, which contain one, 18 and 17 species respectively. We provide a key to the 11 genera of the Monodoraeae and describe four new species to science: Uvariodendron kimbozaense Dagallier & Couvreur, sp. nov., Uvariodendron mossambicense Robson ex Dagallier & Couvreur, sp. nov., Uvariodendron pilosicarpum Dagallier & Couvreur, sp. nov. and Uvariopsis oligocarpa Dagallier & Couvreur, sp. nov., and provide provisional descriptions of three putatively new species. We also present lectotypifications and nomenclatural changes implying synonymies and new combinations (Uvariodendron citriodorum (Le Thomas) Dagallier & Couvreur, comb. et stat. nov., Uvariodendron fuscum var. magnificum (Verdc.) Dagallier & Couvreur, comb. et stat. nov., Uvariopsis congensis var. angustifolia Dagallier & Couvreur, var. nov., Uvariopsis guineensis var. globiflora (Keay) Dagallier & Couvreur, comb. et stat. nov., and Uvariopsis solheidii var. letestui (Pellegr.) Dagallier & Couvreur, comb. et stat. nov.). [ABSTRACT FROM AUTHOR]

The assessment of the fatigue crack growth rate behavior of welded structural components made of ultra-high strength steels (UHHS) is very important to gain a comprehensive understanding of these materials under high-cycle fatigue loadings and to enhance their applications in the construction industry. The literature on the fatigue crack growth rates of welded ultra-high strength steel plates with nominal yield strengths higher than 690 MPa is very scarce and only very limited research has been done thus far to provide the Paris' Law fatigue material constants for welded UHSS components in terms of the base metal (BM), the weld metal (WM), and the heat-affected zone (HAZ) regions, which are essential for fatigue life prediction. Hence, the fatigue crack growth rates of butt-welded UHSS plates with three grades (S700, S960, and S1100) are experimentally investigated in this study using Paris' Law for these three different regions of the welded components. Gas metal arc welding (GMAW) and laser welding (LW) methods are adopted to analyze the influence of welding methods on each steel grade with respect to their static and fatigue strength, microstructural changes, and hardness. In the fatigue crack growth rate test, it was observed that the S700 base material shows the lowest fatigue crack propagation resistance amongst these three grades. In welded components, laser welding outperforms gas welding in terms of the fatigue crack growth resistance. Comparisons of fatigue crack growth behaviors are made among all three tested UHSSs as well as with those from the literature. [ABSTRACT FROM AUTHOR]

The interrelationships of the extant crocodylians Gavialis gangeticus and Tomistoma schlegelii have been historically disputed. Whereas molecular analyses indicate a sister taxon relationship between these two gavialoid species, morphological datasets typically place Gavialis as the outgroup to all other extant crocodylians. Recent morphological‐based phylogenetic analyses have begun to resolve this discrepancy, recovering Gavialis as the closest living relative of Tomistoma; however, several stratigraphically early fossil taxa are recovered as closer to Gavialis than Tomistoma, resulting in anomalously early divergence timings. As such, additional morphological data might be required to resolve these remaining discrepancies. 'Tomistoma' dowsoni is an extinct species of gavialoid from the Miocene of North Africa. Utilising CT scans of a near‐complete, referred skull, we reconstruct the neuroanatomy and neurosensory apparatus of 'Tomistoma' dowsoni. Based on qualitative and quantitative morphometric comparisons with other crocodyliforms, the neuroanatomy of 'Tomistoma' dowsoni is characterised by an intermediate morphology between the two extant gavialoids, more closely resembling Gavialis. This mirrors the results of recent studies based on the external anatomy of these three species and other fossil gavialoids. Several neuroanatomical features of these species appear to reflect ecological and/or phylogenetic signals. For example, the 'simple' morphology of their neurosensory apparatus is broadly similar to that of other long and narrow‐snouted (longirostrine), aquatic crocodyliforms. A dorsoventrally short, anteroposteriorly long endosseous labyrinth is also associated with longirostry. These features indicate that snout and skull morphology, which are themselves partly constrained by ecology, exert an influence on neuroanatomical morphology, as has also been recognised in birds and turtles. Conversely, the presence of a pterygoid bulla in Gavialis and several extinct gavialoids, and its absence in Tomistoma schlegelii, could be interpreted as a phylogenetic signal of crocodylians more closely related to Gavialis than to Tomistoma. Evaluation of additional fossil gavialoids will be needed to further test whether these and other neuroanatomical features primarily reflect a phylogenetic or ecological signal. By incorporating such previously inaccessible information of extinct and extant gavialoids into phylogenetic and macroecological studies, we can potentially further constrain the clade's interrelationships, as well as evaluate the timing and ecological association of the evolution of these neuroanatomical features. Finally, our study supports recent phylogenetic analyses that place 'Tomistoma' dowsoni as being phylogenetically closer to Gavialis gangeticus than to Tomistoma schlegelii, indicating the necessity of a taxonomic revision of this fossil species. [ABSTRACT FROM AUTHOR]