Oxalis_Table_S1_Dryad_update

Contains GenBank accession number

<i>Squamellaria vanuatuensis</i> Jebb & C.R.Huxley, spec. nov.

<p>(<b>A</b>). Habit showing the domatium; (<b>B</b>). Inner view of flower throat; (<b>C</b>). Hypanthium and calyx. Scale bar 5 cm for <b>A</b>; 5 mm for <b>B</b> and <b>C</b>. Drawn by Rosemary Wise from herbarium specimens: <b>A</b> = <i>L</i>. <i>Bernardi 13238</i> (G, barcode G-62446); <b>B, C</b> = Green 1274 (K, barcode K000772005).</p

Photos of the 12 <i>Squamellaria</i> species and phylogenetic relationships among them.

<p>(<b>A</b>) <i>Squamellaria thekii</i>. (<b>B</b>) <i>S</i>. <i>wilsonii</i>. (<b>C</b>) <i>S</i>. <i>major</i>. (<b>D</b>) <i>S</i>. <i>huxleyana</i> Chomicki, sp. nov. (<b>E</b>) <i>S</i>. <i>imberbis</i>. (<b>F</b>) <i>S</i>. <i>grayi</i>, Chomicki & Wistuba, sp. nov. (<b>G</b>) <i>S</i>. <i>tenuiflora</i> comb. nov. (<b>H</b>) <i>S</i>. <i>wilkinsonii</i> comb. nov. (<b>I</b>) <i>S</i>. <i>jebbiana</i> Chomicki, sp. nov. (<b>J</b>) <i>S</i>. <i>kajewskii</i> comb. nov. (<b>K</b>) <i>S</i>. <i>guppyana</i> comb. nov. (<b>L</b>) <i>S</i>. <i>vanuatuensis</i>, sp. nov. (<b>M</b>) Maximum likelihood phylogenetic tree of the genus <i>Squamellaria</i> based on up to combined plastid and nuclear DNA regions (outgroups not shown). Numbers above branches are the maximum likelihood bootstrap support values, followed by the posterior probabilities from a Bayesian analysis of the same dataset. Asterisks above branches (*) indicate a maximal support (100 and 1 for ML and Bayesian analyses, respectively). Color-coding of the species names refers to obligate symbiosis with <i>Philidris nagasau</i> ants (red), facultative symbiosis with various ant species (green), or no symbiosis with ants (blue). Asterisks after species names refer to names that have been transferred to <i>Squamellaria</i>. An ‘S’ after species name refers to the presence of squamellae. Photographic credits: G. Chomicki except (J-K): Derrick Rowe and (L): Bruno Corbara.</p

Isotype of <i>Squamellaria grayi</i>, G. Chomicki, J. Aroles, N. Naikatini 53 (M, barcode: M-0274839).

<p>Isotype of <i>Squamellaria grayi</i>, G. Chomicki, J. Aroles, N. Naikatini 53 (M, barcode: M-0274839).</p

δ ¹³C value in Fijian <i>Squamellaria</i>.

<p>A value below 20‰ is suggestive of CAM metabolism, around 20‰ implies an intermediate CAM/C3 metabolism and above 20‰ indicates C3 metabolism. In all cases, Isotope-Ratio Mass Spectrometry (IR-MS) measurements were measured on leaves.</p

Evolutionary Relationships and Biogeography of the Ant-Epiphytic Genus <i>Squamellaria</i> (Rubiaceae: Psychotrieae) and Their Taxonomic Implications

<div><p>Ecological research on ant/plant symbioses in Fiji, combined with molecular phylogenetics, has brought to light four new species of <i>Squamellaria</i> in the subtribe Hydnophytinae of the Rubiaceae tribe Psychotrieae and revealed that four other species, previously in <i>Hydnophytum</i>, need to be transferred to <i>Squamellaria</i>. The diagnoses of the new species are based on morphological and DNA traits, with further insights from microCT scanning of flowers and leaf <i>δ</i>^<i>13</i><i>C</i> ratios (associated with Crassulacean acid metabolism). Our field and phylogenetic work results in a new circumscription of the genus <i>Squamellaria</i>, which now contains 12 species (to which we also provide a taxonomic key), not 3 as in the last revision. A clock-dated phylogeny and a model-testing biogeographic framework were used to infer the broader geographic history of rubiaceous ant plants in the Pacific, specifically the successive expansion of <i>Squamellaria</i> to Vanuatu, the Solomon Islands, and Fiji. The colonization of Vanuatu may have occurred from Fiji, when these islands were still in the same insular arc, while the colonization of the Solomon islands may have occurred after the separation of this island from the Fiji/Vanuatu arc. Some of these ant-housing epiphytes must have dispersed with their specialized ants, for instance attached to floating timber. Others acquired new ant symbionts on different islands.</p></div

Renner and Won Data Set

Renner and Won Data Se

Phylogeny and biogeographic history of the Pacific Hydnophytinae, inferred under the DEC+J model (see Table 2) on the BEAST chronogram.

<p>Phylogeny and biogeographic history of the Pacific Hydnophytinae, inferred under the DEC+J model (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0151317#pone.0151317.t002" target="_blank">Table 2</a>) on the BEAST chronogram.</p

Geographic distribution of the 12 <i>Squamellaria</i> species.

<p>Geographic distribution of the 12 <i>Squamellaria</i> species.</p

Isotype of <i>Squamellaria jebbiana</i>, G. Chomicki, J. Aroles, N. Naikatini 74 (M, barcode: M-0274837).

<p>Isotype of <i>Squamellaria jebbiana</i>, G. Chomicki, J. Aroles, N. Naikatini 74 (M, barcode: M-0274837).</p