Fig 1.
Concatenated 18S and CO1 gene tree summary.
Percent bootstrap values are given at each node. The clade representing Dolichomicrostomida is highlighted in light grey, with Microstomidae further denoted in dark grey.
Fig 2.
bPTP analysis of 18S and CO1 gene tree.
A maximum of five specimens were chosen for each species. Specimens are listed with the isolate label in parentheses. At each node, percent bootstrap values (black above) and bPTP (red below) values are given. Transitions from blue to red lines highlight species according to the results of the bPTP analysis.
Fig 3.
A. Drawing of ventral view. B. Micropictograph of side view. ap adhesive papillae; b brain; c ciliary pits; i intestine; m mouth; n nematocysts; ph pharynx; r rhabdites.
Fig 4.
Microstomum curinigalletti sp. nov.
A. Drawing of whole body. B. Micropictograph of whole body C. Anterior end with focus on the ciliary pits. D. Posterior end. ap adhesive papillae; b brain; c ciliary pits; i intestine; m mouth; ph pharynx; r rhabdites.
Fig 5.
Microstomum inexcultus sp. nov.
A. Drawing of whole body. B. Micropictograph of whole body C. Anterior end. D. Posterior end with focus on adhesive papillae. ap adhesive papillae; b brain; c ciliary pits; i intestine; m mouth; n nematocysts; ph pharynx.
Fig 6.
A. Drawing of whole body. B. Micropictograph of whole body C. Anterior end with focus on adhesive papillae. D. Anterior end with focus on ciliary pits E. Posterior end with focus on adhesive papillae. ap adhesive papillae; b brain; c ciliary pits; i intestine; m mouth; ph pharynx; r rhabdites.
Fig 7.
Microstomum marisrubri sp. nov.
A. Drawing of whole body. B. Micropictograph of whole body C. Posterior end with focus on the nematocysts. D. Posterior end with focus on the adhesive papillae. E. Male stylet. ap adhesive papillae; b brain; c ciliary pits; i intestine; m mouth; mp male pore; n nematocyst; ph pharynx; r rhabdites; s male stylet; t testis; vg vesicula granulorum.
Fig 8.
A. Drawing of whole body. B. Micropictograph of whole body C. Anterior end with focus on the ciliary pits. D. Male stylet. E. Sperm. ap adhesive papillae; b brain; c ciliary pits; i intestine; m mouth; o ovary; ph pharynx; r rhabdites; s male stylet; vg vesicula granulorum.
Fig 9.
A. Drawing of whole body. B. Micropictograph of whole body C. Anterior end side view. D. Anterior end with focus on adhesive papillae. ap adhesive papillae; b brain; c ciliary pits; i intestine; m mouth; ph pharynx; r rhabdites.
Fig 10.
Microstomum westbladi nom. nov.
A. Drawing of whole body. B. Micropictograph of whole body C. Anterior end focus on adhesive papillae. D. Anterior end with focus on rhabdite field. ap adhesive papillae; b brain; c ciliary pits; i intestine; m mouth; ph pharynx; r rhabdites; s male stylet.
Fig 11.
Different shapes of the anterior ends within Microstomum.
A. Drawing depicting the elongated frontal end of M. trichotum. B. Drawing depicting an anterior proboscis. C. Micropictograph of the proboscis of M. compositum. D. Drawing depicting a conical anterior. E. Micropictograph of the conical anterior of M. lineare. F. Micropictograph of the conical anterior of M. bispiralis. G. Drawing depicting a blunt anterior. H. Drawing depicting a rounded anterior. I. Micropictograph depicting the rounded anterior of M. septentrionale. b brain; ph pharynx.
Fig 12.
Different shapes of the posterior ends within Microstomum.
A. Drawing depicting a rounded posterior. B. Drawing depicting a blunt posterior. C. Micropictograph of the blunt posterior of M. edmondi. D. Drawing depicting a thin-tail posterior of e.g. M. giganteum. E. Drawing depicting a spatulate posterior. F. Micropictograph of the spatulate posterior of M. lotti. G. Drawing depicting a tail-like posterior. H. Drawing depicting a pointed posterior. I. Micropictograph depicting the pointed posterior of M. bispiralis.
Fig 13.
Different shapes of the ciliary pits within Microstomum.
A. Drawing depicting bottle-shaped ciliary pits. B. Micropictograph of the bottle-shaped ciliary pits of M. edmondi. C. Drawing of rounded ciliary pits. D. Micropictograph of the rounded ciliary pits of M. rubromaculatum. Arrows indicate ciliary pits; b brain; ph pharynx.
Fig 14.
Different lengths of the preoral intestine within Microstomum.
A. Drawing depicting a long preoral intestine that extends anterior to the brain. B. Micropictograph of the long preoral intestine of M. inexcultus sp. nov. C. Drawing depicting a medium preoral intestine that terminates at the level of the brain. D. Micropictograph of the medium preoral intestine of M. septentrionale. E. Drawing depicting a short preoral intestine that terminates posterior to the brain. D. Micropictograph of the short preoral intestine of M. bispiralis. b brain; i intestine; m mouth; ph pharynx.
Fig 15.
Different shapes of the pharynx within Microstomum.
A. Drawing depicting the characteristic biparte pharynx of e.g. M. breviceps. B. Drawing depicting a typically-shaped pharynx of Microstomum C. Micropictograph of the typically-shaped pharynx of M. bispiralis. b brain; i intestine; m mouth; ph pharynx.
Table 1.
A key to the species of Microstomidae.
Fig 16.
Examples of limnic Microstomum.
A. M. lineare B. M. zicklerorum C. M. tchaikovskyi D. M. artoisi E. M. bispiralis. Bar = 200 μm.
Fig 17.
Microstomum bispiralis; specimen from Sweden.
A. Micropictograph of whole body B. Anterior end. C. Posterior end with focus on sexual anatomy. b brain; c ciliary pits; i intestine; mp male pore; n nematocyst; ph pharynx; s male stylet; t testis; vg vesicula granulorum.
Fig 18.
Examples of marine Microstomum.
A. M. edmondi B. M. laurae C. M. rubromaculatum D. M. papillosum E. M. crildensis F. M. compositum G. M. septentrionale. Bar = 100 μm.