DOI: 10.5061/dryad.3n5tb2rhg
title: Taxonomic studies on Malagasy Dalbergia (Fabaceae). III. Two new species from Southeastern Madagascar and an emended description of the rosewood species D. maritima

description: The Malagasy rosewood species Dalbergia maritima has a long history of
 unsustainable exploitation for its beautiful, burgundy-colored heartwood.
 As currently circumscribed, D. maritima has a wide geographic distribution
 in eastern Madagascar and exhibits significant morphological, ecological,
 and genetic variation, suggesting it may comprise more than a single
 entity. Multivariate analyses of leaf, flower, and inflorescence
 characters as well as eco-geographic features reveal several
 morphologically well delimited entities with distinct habitat preferences
 and/or geographic ranges, which are consistent with results from recent
 phylogenomic and population genomic studies of Malagasy Dalbergia. Based
 on these findings, we describe and illustrate two new species from
 southeastern Madagascar comprising material previously assigned to D.
 maritima, viz. D. pseudomaritima, characterized by paniculate
 inflorescences and small, broadly elliptic to orbicular, glabrous
 leaflets, and D. razakamalalae, distinguished by racemose inflorescences
 with large flowers, and narrowly ovate to narrowly elliptic, glabrous
 leaflets. Dalbergia maritima is consequently re-circumscribed to include
 only populations from east-central Madagascar, within which we recognize
 two subspecies, D. maritima subsp. maritima, with glabrous leaves,
 inflorescence axes, and gynoecia, occurring in littoral forest habitats,
 and D. maritima subsp. pubescens, with indument on these structures, and
 growing in evergreen humid forest farther inland. Photos are provided for
 each taxon, along with line drawings for the two new species. Provisional
 IUCN Red List assessments indicate that all three species are Endangered,
 D. maritima and D. razakamalalae mainly because of selective logging for
 trade in their high-quality heartwood, and D. pseudomaritima primarily
 because of habitat degradation due to land clearing and fire for
 subsistence agriculture, which has important implications for their
 conservation and sustainable management.
description: 1. Methods for collection / processing the data:
 <br><br>    Morphological Measurements<br>        We
 assessed 13 leaf and leaflet characters (Supplementary Material 3), along
 with<br>        11 inflorescence and flower characters
 (Supplementary Material 4). Continuous and<br>        discrete
 characters (see Manuscript Table 1), which were measured several times
 on<br>        a given collection, were recorded as sample
 medians.<br>        <br>    Ecological
 Characteristics<br>        We assessed 17 potentially relevant
 ecological characteristics (Supplementary <br>        Material 5)
 from available spatial raster or vector data for Madagascar
 (see<br>        Manuscript Table 2).<br>        <br>  
      We used R (R Core Team 2020) version 4.0.2 and the elevatr package
 (Hollister et<br>        al. 2020) version 0.3.1, the terra package
 (Hijmans 2021) version 1.0.10, and the<br>        fasterRaster
 package (Smith 2020) version 0.6.0 to download high-resolution<br>  
      elevation data (3 arc seconds, ca. 90 m resolution) and to perform
 raster<br>        calculations.<br>        <br>       
 All rasters were projected to Universal Transverse Mercator (UTM) zone 38S
 and<br>        re-sampled to the resolution of the highest-resolved
 raster (30 m) when needed.<br>        We then extracted the
 ecological characteristics of the selected collections,<br>       
 resulting in an ecological dataset for multivariate analysis.<br>  
              <br>    Multivariate analyses<br>       
 Commented R code documenting the extraction of ecological characteristics
 from<br>        occurrence data as well as all panels of Figure 3 is
 available in<br>        SupplementaryMaterial_2.R.
description: 2. Instrument- or software-specific information needed to
 interpret the data: <br><br>    This is the R session info
 documenting the R and R package versions used<br><br>  
  &gt; sessionInfo()<br>    R version 4.0.2
 (2020-06-22)<br>    Platform: x86_64-apple-darwin17.0
 (64-bit)<br>    Running under: macOS Catalina
 10.15.7<br><br>    Matrix products: default<br>  
  BLAS:  
 /System/Library/Frameworks/Accelerate.framework/Versions/A/Frameworks/vecLib.framework/Versions/A/libBLAS.dylib<br>    LAPACK: /Library/Frameworks/R.framework/Versions/4.0/Resources/lib/libRlapack.dylib<br><br>    locale:<br>    [1] en_US.UTF-8/en_US.UTF-8/en_US.UTF-8/C/en_US.UTF-8/en_US.UTF-8<br><br>    attached base packages:<br>    [1] stats     graphics  grDevices utils     datasets  methods   base     <br><br>    other attached packages:<br>      [1] XML_3.99-0.8     rgdal_1.5-27     cleangeo_0.2-4   maptools_1.1-2   rgeos_0.5-8      ggrepel_0.9.1   <br>      [7] ggforce_0.3.3    ggplot2_3.3.5    rmapshaper_0.4.5 concaveman_1.1.0 tmap_3.3-2       alphahull_2.2   <br>    [13] ConR_1.3.0       raster_3.5-2     sp_1.4-6         terra_1.4-22     ape_5.5          cluster_2.1.2   <br>    [19] adegenet_2.1.5   ade4_1.7-18      tabplot_1.4.1    ffbase_0.13.3    ff_4.0.5         bit_4.0.4   <br><br><br>3. Describe any quality-assurance procedures performed on the data: <br><br>    Some missing values in the measurement dataset were imputed using class means before<br>    subjecting it to multivariate analyses (PCA, PCoA), see R functions impute and ordplot.<br>    <br>    Missing data code is "NA".<br><br><br>4. People involved with sample collection, processing, analysis and/or submission: <br><br>    Simon Crameri, Nivohenintsoa Rakotonirina