Table 5. Species recorded from more than one zoogeographic
realm, i.e. evidence for recent LDD ( – the most probable realm of
origin; – most probably natural dispersion; – most probably
anthropogenic dispersion).
Figure 1. Approximate localities of the 127 Milnesiumpopulations analysed in this study (see Supplementary Materials SM.01
for details). Yellow circles indicate the newly analysed populations
(N=83), whereas red circles stand for data retrieved from the literature
(N=44).
Figure 2. Simplified Bayesian Inference time calibrated
phylogenetic tree based on concatenated 18S rRNA+28S rRNA+ITS-2+COI
nucleotide sequences obtained with BEAST (left) and its relation to the
most recent published phylogeny of Milnesium by Morek &
Michalczyk (2020) (right). The left side tree: the upper values at nodes
indicate the 95% Highest Posterior Density, which is graphically
presented as the blue bar, whereas the lower values provide the
Posterior Probability (PP) supports. Yellow circles superimposed on
nodes indicate the two calibration points used as tree priors. The
dashed branches indicate phylogenetic uncertainty. The main geological
eras as well as the estimated time of the Gondwana breakup (vertical
grey bar) are marked. The Mya stands for Million years ago. The six main
clades within Milnesium (A–F) are collapsed and their sizes
indicate the number of populations within each clade in both
phylogenetic trees. The percentages within the collapsed clades indicate
the support for the origin of the ancestor in given zoogeographic realm
(see Results for more details). See Figs 3–5 for detailed relationships
within each of the main clades uncovered in this study. The right side
tree: values at nodes represent PP supports and the scale bar shows the
number of substitutions per site. The arrows between both trees show the
relationship between clades obtained in this contribution and in the
phylogeny by Morek & Michalczyk (2020). The pie chart below indicates
the number of species detected in the genus Milnesium to date
divided into three categories (blue – species described under the
integrative taxonomy framework; green – classically described species,
i.e. of which phylogenetic position is unknown; yellow – undescribed
putative new species detected in this study).
Figure 3. Milnesium phylogeny: clades A and B
reconstructed using the time calibrated Bayesian Inference based on
concatenated 18S rRNA+28S rRNA+ITS-2+COI nucleotide sequences obtained
with BEAST (see Fig. 2 for the entire tree). Values at nodes represent
Posterior Probability (PP) supports and the scale indicates the time
before present in Millions of years. Black vertical bars right to the
population codes encompass species delineated using both phylogeny and
morphology, whereas thin grey vertical lines indicate putative species
suggested by the bPTP analysis alone and that did not agree with the
integrative species delineation; numbers within vertical black bars are
running species numbers (see Results for more details on species
delineation). Further right, zoogeographic origin, climate type and
reproductive mode are indicated by numbered and differently coloured
squares. Colour and number coding are explained in the legend in Fig. 5.
Figure 4. Milnesium phylogeny: clades C and D
reconstructed using the time calibrated Bayesian Inference based on
concatenated 18S rRNA+28S rRNA+ITS-2+COI nucleotide sequences obtained
with BEAST (see Fig. 2 for the entire tree). Values at nodes represent
Posterior Probability (PP) supports and the scale indicates the time
before present in Millions of years. Black vertical bars right to the
population codes encompass species delineated using both phylogeny and
morphology, whereas thin grey vertical lines indicate putative species
suggested by the bPTP analysis alone and that did not agree with the
integrative species delineation; numbers within vertical black bars are
running species numbers (see Results for more details on species
delineation). Further right, zoogeographic origin, climate type and
reproductive mode are indicated by numbered and differently coloured
squares. Colour and number coding are explained in Fig. 5.
Figure 5. Milnesium phylogeny: clades E and F
reconstructed using the time calibrated Bayesian Inference based on
concatenated 18S rRNA+28S rRNA+ITS-2+COI nucleotide sequences obtained
with BEAST (see Fig. 2 for the entire tree). Values at nodes represent
Posterior Probability (PP) supports and the scale indicates the time
before present in Millions of years. Black vertical bars right to the
population codes encompass species delineated using both phylogeny and
morphology, whereas thin grey vertical lines indicate putative species
suggested by the bPTP analysis alone and that did not agree with the
integrative species delineation; numbers within vertical black bars are
running species numbers (see Results for more details on species
delineation). Further right, zoogeographic origin, climate type and
reproductive mode are indicated by numbered and differently coloured
squares. Colour and number coding are explained in the legend at the
bottom of the tree.
Figure 6. The summary and interpretation of distribution
patterns of Milnesium species recovered in this study. Species
with limited ranges = species found only in a single zoogeographic
realm; widespread species = species found in more than one zoogeographic
realm (i.e. suggesting recent Long Distance Dispersal, LDD); ‘inclusion
species’ = species that were found in a different zoogeographic realm
than the majority of species in a given clade (i.e. suggesting ancient
dispersal); SSD = Short Distance Dispersal (refers to species found in
localities close to the borders of adjacent zoogeographic realms).
Overall, there were 86% species showing no evidence for natural LDD and
14% species suggesting natural LDD (mostly ancient, only rarely
recent).