Valéry Malécot

A new subfamily classification of the leguminosae based on a taxonomically comprehensive phylogeny

The classification of the legume family proposed here addresses the long-known non-monophyly of the traditionally recognised subfamily Caesalpinioideae, by recognising six robustly supported monophyletic subfamilies. This new classification uses as its framework the most comprehensive phylogenetic analyses of legumes to date, based on plastid matK gene sequences, and including near-complete sampling of genera (698 of the currently recognised 765 genera) and ca. 20% (3696) nof known species. The matK gene region has been the most widely sequenced across the legumes, and in most legume lineages, this gene region is sufficiently variable to yield well-supported clades. This analysis resolves the same major clades as in other phylogenies of whole plastid and nuclear gene sets (with much sparser taxon sampling). Our analysis improves upon previous studies that have used large phylogenies of the Leguminosae for addressing evolutionary questions, because it maximises ngeneric sampling and provides a phylogenetic tree that is based on a fully curated set of sequences that are vouchered and taxonomically validated. The phylogenetic trees obtained and the underlying data are available to browse and download, facilitating subsequent analyses that require evolutionary trees. Here we propose a new community-endorsed classification of the family that reflects the phylogenetic structure that is consistently resolved and recognises six subfamilies in Leguminosae: na recircumscribed Caesalpinioideae DC., Cercidoideae Legume Phylogeny Working Group (stat. nov.), Detarioideae Burmeist., Dialioideae Legume Phylogeny Working Group (stat. nov.), Duparquetioideae Legume Phylogeny Working Group (stat. nov.), and Papilionoideae DC. The traditionally recognised subfamily Mimosoideae is a distinct clade nested within the recircumscribed nCaesalpinioideae and is referred to informally as the mimosoid clade pending a forthcoming formal tribal and/or cladebased classification of the new Caesalpinioideae. We provide a key for subfamily identification, descriptions with diagnostic charactertistics for the subfamilies, figures illustrating their floral and fruit diversity, and lists of genera by subfamily. This new classification of Leguminosae represents a consensus view of the international legume systematics community; it invokes nboth compromise and practicality of use.

Molecular Phylogenetic Relationships of Olacaceae and Related Santalales

Abstract As traditionally circumscribed, the family Olacaceae contains a morphologically diverse assemblage of genera that has historically caused much confusion regarding their classification. For example, Olacaceae contain parasites and nonparasites, climbing lianas and trees, and members with dichlamydous and monochlamydous perianths. This family is basalmost in the sandalwood order (Santalales), thus it represents the staging ground for many innovations that evolved in subsequent groups. The present molecular phylogenetic study has obtained DNA sequence data (nuclear SSU rDNA and chloroplast rbcL and matK) for all but two of the 28 genera in this group. Maximum parsimony and Bayesian analyses have resolved seven clades, well-supported by molecular and morphological characters. Root hemiparasitism appears to have first evolved in the clade containing Ximenia whereas clades between that one and the outgroup appear to be entirely autotrophic.

A Morphological Cladistic Analysis of Olacaceae

Abstract A cladistic study based on morphological characters is presented for all 28 genera of Olacaceae as well as 26 representative genera from five other families of Santalales: Loranthaceae, Misodendraceae, Opiliaceae, Santalaceae, and Viscaceae. The data matrix consists of 80 macro-morphological, palynological, and anatomical characters. The phylogenetic trees obtained show a paraphyletic Olacaceae with four main clades. Some of these clades are congruent with previously recognized tribes, but all of subfamilies are para- or polyphyletic. Examination of character transformations confirms several assumptions of evolutionary trends within Olacaceae and Santalales, but others appear to be more complex than expected. Optimization of trophic mode on the consensus tree shows that root hemiparasitism had a single origin in Santalales. Whatever the optimization procedure used, the basal-most clade of Olacaceae consists of 12 genera, among which five are known to be autotrophs, whereas the remaining three clades (15 genera) contain four genera known to be root parasites.

Nineteenth century French rose (Rosa sp.) germplasm shows a shift over time from a European to an Asian genetic background

Highlight The impact of breeding on the genetic diversity and structure of roses, during the 19th century in Europe, was studied using a genetic and historical interdisciplinary approach.

Report of the Special Committee on Registration of Algal and Plant Names (including fossils)

The Special Committee on Registration of Algal and Plant Names (including fossils) was established at the XVIII International Botanical Congress (IBC) in Melbourne in 2011, its mandate being to consider what would be involved in registering algal and plant names (including fossils), using a procedure analogous to that for fungal names agreed upon in Melbourne and included as Art. 42 in the International Code of Nomenclature for algae, fungi, and plants. Because experience with voluntary registration was key to persuading mycologists of the advantages of mandatory registration, we began by asking institutions with a history of nomenclatural indexing to develop mechanisms that would permit registration. The task proved more difficult than anticipated, but considerable progress has been made, as is described in this report. It also became evident that the Nomenclature Section needs a structure that will allow ongoing discussion of registration and associated issues. Simultaneously with this report we are submitting four proposals that would provide such a structure.

A survey of species assigned to the fossil pollen genus Anacolosidites

Anacolosidites Cookson & Pike, a fossil pollen genus recorded since the Campanian, is peculiar in its morphology – six‐porate with three apertures on each hemisphere, located away from the equator, and with the distal and proximal apertures positioned over each other. Representatives of this fossil genus are widely considered to represent extant Olacaceae from tribe Anacoloseae. Olacaceae is an exclusively tropical angiosperm family with a pantropical distribution; consequently the fossils are often used to suggest a tropical climate and in addition are frequently used as a stratigraphic marker. Fossil species assigned to Anacolosidites are quite variable and may not all represent Olacaceae, in which case they may not indicate tropical climate. The present study is a morphological survey of fossil pollen assigned to Anacolosidites; it identifies the published reports of the fossil species that probably represent positive occurrences of Olacaceae pollen in the fossil record. Within Olacaceae, Anacolosidites‐type pollen is usually compared with pollen of genera in tribe Anacoloseae, in particular: Cathedra, Anacolosa and Phanerodiscus, but never with the pollen of Ptychopetalum, a genus from tribe Olaceae with closely similar pollen to the other three genera, but with a reticulate tectum and very small circular apertures located near the equator. Nevertheless, the records of reticulate Anacolosidites species which have been excluded from the emended diagnosis are unlikely to be related to Ptychopetalum. The earliest accepted record of Anacolosidites is from the Late Cretaceous (Maastrichtian) of Germany. However, most Late Cretaceous records, and later Russian and Chinese occurrences referred to Anacolosidites, consist mainly of Normapolles‐type pollen, whereas many of the Cenozoic records assigned to Anacolosidites have a much clearer affinity with the pollen of Anacolosa, Cathedra and Phanerodiscus (tribe Anacoloseae). The newly emended genus Anacolosidites may be used as a stratigraphic marker for tropical or megathermal climatic conditions.

Staufferia and Pilgerina: Two New Endemic Monotypic Arborescent Genera of Santalaceae from Madagascar

Abstract Two new arborescent species of Santalaceae, both endemic to Madagascar, are described in the new monotypic genera, Staufferia Z. S. Rogers, Nickrent & Malécot and Pilgerina Z. S. Rogers, Nickrent & Malécot. Based on available molecular and morphological data, the new species are part of a clade formed with Pyrularia Michx. of Asia and North America, the Indo-Malesian genus Scleropyrum Arn., and the central and western African Okoubaka Pellegr. & Normand. Staufferia is distinguished morphologically from Okoubaka by the smaller inflorescences (4 to 10 vs. 50 to 100 flowers); smaller (1.8–2 × 1.1–1.6 cm vs. ca. 9 × 5 cm), obovoidal (vs. ellipsoidal) fruits; smaller (ca. 1.5 mm vs. 7–8 mm diam.), persistent perianth; thinner (0.5–1 mm vs. 15–20 mm thick), 5-sulcate (vs. smooth) exocarp; and thinner (ca. 0.5 mm vs. 3–4 mm thick), smooth (vs. deeply striate or alveolate) mesocarp. Pilgerina differs from Scleropyrum by the smaller inflorescences (8 to 23 vs. 60 to 100 flowers); pedicellate (vs. sessile) flowers; smaller (1.2–1.9 × 1.7–2.7 cm vs. ca. 3 × 2 cm), broadly transversely ellipsoidal to subspheroidal (vs. obovoidal to pyriform) fruits; and thinner (ca. 0.5 mm vs. 1.5–3 mm thick), smooth or finely striate (vs. deeply striate or alveolate) mesocarp. Both species are illustrated and assigned an IUCN preliminary conservation status of Least Concern (LC).

Plant Identification: Experts vs. Machines in the Era of Deep Learning

Automated identification of plants and animals have improved considerably in the last few years, in particular thanks to the recent advances in deep learning. The next big question is how far such automated systems are from the human expertise. Indeed, even the best experts are sometimes confused and/or disagree between each others when validating visual or audio observations of living organism. A picture or a sound actually contains only a partial information that is usually not sufficient to determine the right species with certainty. Quantifying this uncertainty and comparing it to the performance of automated systems is of high interest for both computer scientists and expert naturalists. This chapter reports an experimental study following this idea in the plant domain. In total, nine deep-learning systems implemented by three different research teams were evaluated with regard to nine expert botanists of the French flora. Therefore, we created a small set of plant observations that were identified in the field and revised by experts in order to have a near-perfect golden standard. The main outcome of this work is that the performance of state-of-the-art deep learning models is now close to the most advanced human expertise. This shows that automated plant identification systems are now mature enough for several routine tasks, and can offer very promising tools for autonomous ecological surveillance systems.

Taxonomic revision of West-Alpine cushion plant species belonging to Androsace subsect. Aretia

Abstract High-altitude rockjasmines (genus Androsace) are a paramount example of evolutionary radiations in temperate mountains of the Northern Hemisphere. Yet, we show here that their taxonomy is incomplete and has been subject to many historical mistakes, probably due to the lack of exploration of mountains by the classical botanists who described these species. Here we wish to clarify the application of names with regard to four defined morphotypes, typical of high-elevation zones of the Western Alps, in order to set a definitive basis for morphological delimitation of a likely new species discovered in the Mont Blanc range (species not described in this work). To do so, we review the historical taxonomic treatments and positions, carefully reconsider types and species names for these morphotypes, and designate lectotypes and epitypes for each of them. In particular, we confirm the validity of names commonly used to refer to the taxa Androsace alpina, Androsace helvetica, and Androsace pubescens. We show that Androsace vandellii is an invalid name and that Androsace argentea should be used instead. Our work illustrates the utility of historical herbaria to clarify the taxonomy of complex groups of plants growing in inaccessible environments such as high-altitude regions.