Figure 1.
Sterile, fertile and nuclei in Caulerpas from the Mediterranean area.
Sterile fronds of C. prolifera, C. racemosa var. cylindracea and C. taxifolia from the Mediterranean (A, D, G). Gametogenesis in C. prolifera: C. prolifera with extrusion papillae, mucilage is released from the discharges tubes (B). Optical microscope view and DAPI-stained spherical gametangia containing 8 gametes (C, F). DAPI stained gametangial sacs containing a large number of gametes (E). DAPI-stained nuclei (circular areas point the nuclei), chloroplast circular DNA is also visible (H, J). Scale bars: in A, B, D, G = 1 cm; in C = 10 µm; in E, H, I = 4 µm; in F = 5 µm.
Table 1.
Genome size variation and ploidy levels.
Figure 2.
Nuclear DNA contents in Caulerpas.
Nuclei size histograms measured from DAPI-stained DNA (correlates with genome sizes) for reproductive (A) and non-reproductive (B) species, and populations (C) of Caulerpa from the Mediterranean. Number of nuclei is represented in the Y-axis in all the graphs, and nuclei size classes in µm2 are represented in the X-axis.
Figure 3.
Caulerpa cytotypes in the Mediterranean area.
Diagram of the correspondence of the peaks from DNA content histograms of cytotypes and ploidy levels using the C/Cx terminology of Greilhuber et al. (2005) [67], for the species found in the Mediterranean.
Figure 4.
Variation in minimum genome size.
Variation expressed in area (µm2), between non-reproductive thalli of C. prolifera, C. racemosa var. cylindracea and C. taxifolia, and reproductive C. prolifera (sample size n = 791, 962, 280, 517, respectively). The + near the median bar indicates location of the sample means. Genome of invasive thalli is smaller (F coefficient 603.23, P<0.0001).
Table 2.
One way ANOVA comparing the minimum genome size (G1) in the three Caulerpa species.
Table 3.
One way ANOVA comparing total data in the three Caulerpa species.
Figure 5.
Proposed life history for C. prolifera in the Mediterranean Sea.
(Clone in dominant phase proportionally drawn).