Figure 1.
Pictures of identified morphotypes of Xestospongia testudinaria around Lembeh Island.
a: Digitate; b: Smooth; c: Lamellate; d: Intermediate; e: Digitate close-up; f: Smooth close-up; g: Lamellate close-up; h: Intermediate close-up.
Figure 2.
Distribution of mitochondrial haplotypes per morphotype of Xestospongia testudinaria.
Spatial distribution of mitochondrial Cytochrome Oxidase 1 (CO1) haplotypes (C1-C6, see also Tables 2 & 3) per morphotype of Xestospongia testudinaria (see Figure 1). C1 (red) and C5 (blue) are present at all sampled sites of Lembeh Island. C2 (orange), C3 (yellow), C4 (green) and C6 (purple) are only present in the sheltered center of Lembeh strait north east of the port of Bitung.
Figure 3.
Phylogenetic trees based on mitochondrial and nuclear DNA of Xestospongia testudinaria.
Unrooted maximum likelihood phylogenetic trees of the combined mitochondrial DNA (CO1+ATP6, n=54, 989 base pairs, left) and nuclear intron ATPSβ (n=34, 258-270 base pairs, right) sequences of Xestospongia testudinaria. Symbols denote the assigned morphotype of different individuals, with the number of symbols indicating the number of sampled sponges of a given morphotype with that specific DNA sequence (see legend). The colored boxes of the individual sample numbers in the nuclear DNA phylogeny correspond to the same colored boxes of haplotypes in the mitochondrial tree. These colors correspond with the CO1 haplotypes in Figure 2. Haplotypes with an outlined box in a particular color share the CO1 sequence but vary in ATP6 sequence, resulting in a unique combined haplotype (CO1+ATP6). The letters "a" and "b" in the nuclear gene tree represent heterozygote alleles. Bootstrap values are only shown when > 70%. Scale bars depict substitutions per site.
Figure 4.
Combined haplotype network of Xestospongia sp. from the Caribbean and Lembeh Island.
Haplotype network of eight Cytochrome Oxidase 1 (CO1) mitochondrial haplotypes of giant barrel sponges Xestospongia testudinaria and X. muta. Dotted line encircles haplotypes found in our study of 126 X. testudinaria around Lembeh Island (C1-6). Solid lines encircle haplotypes found in 116 samples of X. muta from the Caribbean (H1-4) [26]. Each line connecting the haplotypes represents a single nucleotide substitution.