Figure 1.
A, habitus of a fully relaxed adult specimen; B, habitus at different focal plane of a different specimen slightly contracted and compressed, arrowhead indicates the pharyngeal pores; C, anterior end of a third specimen showing the insertion of the anterior adhesive tubes (arrowhead); D, close-up of the anterior end of a fourth specimen, showing the arrangement of sensorial cilia and the insertion of the anterior adhesive tubes (arrowhead). A–C, DIC photomicrographs, D, SEM photomicrographs. Scale bars, A–C, 100 µm, D, 20 µm.
Figure 2.
SEM photomicrographs. A, adult specimens, bent, lateral view; C–E, close up of the anterior adhesive tubes from various specimens. Scale bars, A, 50 µm, B–E, 5 µm.
Figure 3.
Anandrodasys agadasys ( = Dactylopodola agadasys) from the US Virgin Islands.
A, habitus of a fully relaxed adult specimen; B, C adhesive tubes of the ventrolateral series of two different adult specimens; D, close-up of the anterior end of a fourth specimens, showing the arrangement of sensorial cilia and the insertion of the anterior adhesive tubes; E, posterior trunk region showing the female reproductive apparatus with eggs at different developing stages. DIC photomicrographs. Scale bars, A, 100 µm, B–E, 20 µm. Originally described from Australia, later the species has been reported from Panama, Red sea, Caribbean sea and Florida [6], [24]. According to Hummon [6] there are not morphological differences among populations. Morphology of the specimens from St John match that describe d by Hummon [6]; however, we noticed some variability in the number and arrangement of the ventrolateral adhesive tubes, as testified by Figures B and C.
Table 1.
New sequenced gastrotrich taxa used in this study.
Table 2.
Additional gastrotrich taxa used in this study.
Figure 4.
Phylogenetic relationships of 43 Gastrotricha Macrodasyida inferred from Bayesian analysis of 18 S rDNA.
The outgroup is represented by Xenotrichula intermedia (Chaetonotida, Xenotrichulidae). Number at nodes represents posterior probabilities.
Figure 5.
Phylogenetic relationships of 43 Gastrotricha Macrodasyida inferred from Maximum Likelihood analsysis of 18 S rDNA.
The outgroup is represented by Xenotrichula intermedia (Chaetonotida, Xenotrichulidae). The tree is drawn to scale, with branch lengths measured in the number of substitutions per site. Number at nodes represents bootstrap values (1000 replicates).
Figure 6.
Phylogenetic relationships of 43 Gastrotricha Macrodasyida inferred from Maximum Parsimony analysis of 18 S rDNA.
The outgroup is represented by Xenotrichula intermedia (Chaetonotida, Xenotrichulidae). Tree #1 out of 3 most parsimonious trees (length = 3746) is shown. The consistency index is (0.382720), the retention index is (0.608797), and the composite index is 0.254573 (0.232999) for all sites and parsimony-informative sites (in parentheses). Number at nodes represents bootstrap values (1000 replicates).