DOI: 10.5061/dryad.6rs00nn
title: Data from: Bolstering species delimitation in difficult species complexes by analyzing herbarium and common garden morphological data: a case study using the New Zealand native Myosotis pygmaea species group (Boraginaceae)

description: Species delimitation in recent radiations is challenging because these
 species often display overlap in their expression of morphological
 characters. Here we analyze morphological characters measured from
 field-collected herbarium specimens and compare them to measurements from
 live plants grown in a common garden to determine reliable characters that
 could be used to delimit species in the Myosotis pygmaea (Boraginaceae)
 species group in New Zealand. This species complex is of primary interest
 because it includes many threatened species as well as several
 taxonomically indeterminate entities. The common garden experiment
 revealed high levels of morphological plasticity within the M. pygmaea
 species group, as plants in the common garden grew to be strikingly larger
 than those in the field. The M. pygmaea species complex was found to be a
 morphologically definable group, and several taxonomically indeterminate
 entities were placed as being either morphologically similar to the M.
 pygmaea species group or to other species complexes. In multidimensional
 scaling analyses of morphological data, of the five named species that
 make up the M. pygmaea species group, three formed separate clusters (M.
 pygmaea, M. glauca, and M. brevis), and the two others were
 indistinguishable from each other (M. antarctica, and M. drucei). This
 study represents an important step towards a planned integrative taxonomic
 revision of the M. pygmaea species group, and highlights the value of
 morphological data collected from a common garden experiment.
description: Pygmy Myosotis
 morphological dataDataset of morphological
 characters measured on pygmy Myosotis and other bracteate-prostrate
 Myosotis species.Pygmy Myosotis morphology data
 for Dryad.xlsxPygmy Myosotis
 morphology data Table 2Field
 descriptions/definitions for the data worksheetTable
 2.pdfSupplementary Table
 1Details of seed
 germination, survival to adulthood and flowering rates in the Myosotis
 pygmaea species group common garden experiment.Supplementary Table
 2Comparison of characters
 differentiating several putative Myosotis taxa from the M. pygmaea species
 group based on herbarium specimen data. For explanation of character
 numbers see Table 2.Supplementary Table
 3Comparison of herbarium
 specimen data showing differences between selected species and some
 putative Myosotis taxa within the M. pygmaea species
 group.Supplementary Table
 4Comparison of characters
 of common garden specimens of Myosotis pygmaea species group individuals;
 values given are mean (range). Measurements taken from live plants. See
 Table 2 for explanation of character numbers. (R) = reproductive, (V) =
 vegetative. P values that are significant at P &lt; 0.01 are denoted with
 an asterisk (“*”), including calyx length at fruiting between M. drucei
 and M. pygmaea (compare with Table S7).Supplementary Figure
 5Non-metric
 multidimensional scaling (nMDS) plot of Myosotis individuals of the
 integrated 141 individual data set, converted to a dissimilarity matrix
 with Gower’s coefficient. Three dimensions were retained. Clusters and
 individual uncertainty calculated using “mclust” is
 shown.Supplementary_file_5.pngSupplementary Table 6Comparison of characters between common garden and herbarium plants of Myosotis pygmaea species group individuals. For explanation of character numbers see Table 2. (R) = reproductive, (V) = vegetative.Supplementary Table 7Additional comparisons of herbarium data between individuals of the Myosotis pygmaea species group, highlighting three of the characters that found significant differences between species in the common garden data, as well as varying significantly between the herbarium and common garden datasets (Table S6). For explanation of character numbers see Table 2. P values that are significant at P &lt; 0.01 are denoted with an asterisk (“*”), for calyx length at fruiting between M. drucei and M. pygmaea compare with Table S4.