Fig 1.
Mutualism between Triplaris and Pseudomyrmex.
Ants of P. triplaridis establish their colonies in the hollow stems of T. americana.
Table 1.
Statistics for the gene regions used for Triplaris and Pseudomyrmex.
Table 2.
Partitions and models for Maximum Likelihood (ML) and Bayesian inference based on PartitionFinder.
Fig 2.
Phylograms obtained from Bayesian inference for the interspecific relationships of Triplaris and of Pseudomyrmex with emphasis on the P. triplarinus subgroup (denoted by an asterisk).
Thick lines represent branches supported by posterior probabilities (PP) > 0.95 and Maximum Likelihood (ML) bootstrap values > 90%. Cross symbols indicate PP values between 0.9–0.95 and ML bootstraps between 60% and 90%. A number (1) represents a topology only supported by Bayesian analyses (PP > 0.9) and a (2) a topology supported by ML (bootstrap > 60%). The four obligate symbiont species of ants are highlighted in grey. For collection information see S1 and S2 Tables.
Fig 3.
Tanglegram comparing a reduced phylogeny of Triplaris and of the Pseudomyrmex triplarinus subgroup (denoted by an asterisk).
Colored lines between trees indicate associations reported in the literature, and information derived from Sanchez and Ward collections (same color key as in S3 Table). Dashed lines indicate associations with generalist ants (in grey). Note that T. melaenodendron only associates with generalist ants and Triplaris poeppigiana was only found in association with ants of the genus Azteca (Table 3). Nodes with less than 0.9 PP or 50% bootstrap (based on Fig 2) are denoted by dashed branches.
Table 3.
Percentage of occupancy for Triplaris species based on 184 collections (S3 Table).
Fig 4.
Geographical distribution of all Triplaris and associate obligate Pseudomyrmex ant collections known to date (S3 Table).
Circles represent plant species and triangles ant species. Inserts A to C are zoom-in areas, where several species occur in sympatry. A. Central and northern Colombia. B. San Martin, Peru. C. Acre, Brazil. Colors represent different species, see legend insert.
Fig 5.
Range of distribution for Triplaris (A) and Pseudomyrmex triplarinus subgroup (B) as predicted by DIVA-GIS.
A. The circles represent the 1876 collections of Triplaris; B. Triangles indicate the distribution of the 739 collections of the obligate Pseudomyrmex. In both maps, warmer colors (i.e. orange and red) indicate the areas where the climatic conditions are most suitable for the occurrence of both organisms. Grey areas indicate unsuitable climatic conditions.
Fig 6.
Range overlap between Triplaris and its obligate associate ants as predicted by DIVA-GIS.
Warmer colors (i.e. orange and red) indicate increased likelihood of co-occurrence.