Sea Anemones

Edwardsia elegans.

Anemonia sargassensis.

1. Tealia Crassicornis, 2. 3. Bunodes Cemmacea, 4. S. Ballii; 5. 6. S. Thallia.

1. Sagartia Nivea, 2. 3. 4. S. Miniata,; 5. S. Troglodytes, 6. S. Parasitica, 7. S. Icthystoma .8. 9. S. Ornata.

Sagartia luciae. Oral view.

1. 2. Sagartia Troglodytes, 3. S. Viduata, 4. 5. S. Pallida, 6. S. Pura, 7. 8. Adamsia Palliata.

1. Hormathia Margarita, 2. Phellia Brodricii, 3. Peachia Hasata, 4. P. Undata, 5 Stomphia Churchiae, 6. Ilyanthus Mitchellii.

Figure 3.Anemonia sargassensis. A Live specimen in natural habitat B Oral view C Pedal disc view D Cross section through distal column showing mesenteries; arrows indicate siphonoglyphs E Detail of cross section through distal column showing a siphonoglyph F Detail of retractor and parietobasilar muscles G Longitudinal section through margin showing acrorhagi and marginal sphincter muscle H Longitudinal section through base showing basilar muscles I Cross section through tentacle J–U Cnidae.– acrorhagi: J small basitrich K basitrich L holotrich; actinopharynx: M small basitrich N microbasic p-mastigophore; column: O basitrich; filaments: P basitrich Q microbasic b-mastigophore R microbasic p-mastigophore; tentacle: S small basitrich T basitrich U spirocyst. Abbreviations.– acr: acrorhagi, bm: basilar muscle, e: epidermis, fo: fosse, g: gastrodermis, la: larvae, lm: longitudinal muscle, m: mesoglea, mp: marginal projection, od: oral disc, pd: pedal disc, pm: parietobasilar muscle, rm: retractor muscle, s: siphonoglyph, sp: sphincter, t: tentacle. Scale bars: A–C: 10 mm; D–I: 200 μm; J–U: 25 μm.

Figure 1.Stylobates birtlesi sp. n. holotype MTQ G57579 a, b soon after collection (photo: RA Birtles) c, d preserved specimen with Sympagurus trispinosus showing position of oral disc of anemone e preserved specimen: shortest tentacles beside longest ones (on right side of oral disc in this view); tentacles grade in length between longest and shortest around other side of oral disc (dashed line indicates directive axis) f preserved specimen without hermit crab showing aperture and part of carcinoecium not covered by anemone (arrow). Scale bars 20 mm.

Metridium dianthus. Specimen in process of fission.

Phymactis veratra.

Sagartia luciae. Side view.

Anthea cereus (Opelet).

1. Hormathia Margarita, 2. Phellia Brodricii, 3. Peachia Hasata, 4. P. Undata, 5 Stomphia Churchiae, 6. Ilyanthus Mitchellii.

Figure 4.Anthopleura pallida. A Oral view B Lateral view C Detail of directives and siphonoglyph D Cross section through proximal column E Longitudinal section through margin showing acrorhagi and marginal sphincter muscle F Detail of spermatic cysts G Longitudinal section through distal column showing one verruca H Longitudinal section through base showing basilar muscles I–X Cnidae.– acrorhagi: I small basitrich J basitrich K holotrich L spirocyst; actinopharynx: M small basitrich N basitrich O microbasic b-mastigophore P spirocyst; column: Q small basitrich R basitrich S spirocyst; filament: T basitrich U spirocyst V microbasic p-mastigophore; tentacle: W basitrich X spirocyst. Abbreviations.– acr: acrorhagi, bm: basilar muscle, c: column, d: directives, fo: fosse, mp: marginal projection, od: oral disc, pd: pedal disc, pm: parietobasilar muscle, rm: retractor muscle, s: siphonoglyph, sc: spermatic cyst, sp: sphincter, t: tentacles, vr: verruca. Scale bars: A–B: 10 mm; C–H: 200 μm; I–X: 25 μm.

Figure 2.Longitudinal section through tentacle of Stylobates birtlesi sp. n. paratype MTQ G57580.

Eloactis producta.

Figure 5.Bunodosoma cavernatum. A Live specimen in natural habitat B Oral view C Lateral view D Detail of directives; notice siphonoglyph E Cross section through proximal column showing oocytes F Cross section through tentacle G Longitudinal section through column showing vesicles H Longitudinal section though base showing basilar muscles I Longitudinal section through margin showing acrorhagi and marginal sphincter muscle J–T Cnidae.– acrorhagi: J basitrich K holotrich; actinopharynx: L basitrich M microbasic p-mastigophore; column: N small basitrich O basitrich; filament: P basitrich Q microbasic b-mastigophore R microbasic p-mastigophore; tentacle S basitrich T spirocyst. Abbreviations.– acr: acrorhagi, bm: basilar muscle, c: column, d: directives, e: epidermis, fo: fosse, g: gastrodermis, lm: longitudinal muscles, m: mesoglea, mp: marginal projection, o: oocyst, od: oral disc, pd: pedal disc, pm: parietobasilar muscle, rm: retractor muscle, s: siphonoglyph, sp: sphincter, t: tentacle, vs: vesicles. Scale bars: A–C: 10 mm; D–I: 200 μm; J–T: 25 μm.

Figure 3.Endodermal circumscribed marginal sphincter muscles of Stylobates spp. a, b Palmate marginal sphincter muscle of Stylobates birtlesi sp. n. a paratype MTQ G57581 b paratype KUDIZ 003352 c-e Pinnate marginal sphincter muscles. c Stylobates aeneus (from Dunn et al. 1981) d Stylobates cancrisocia (from Carlgren 1928a) e Stylobates loisetteae (from Fautin 1987).

Figure 6.Isoaulactinia stelloides. A Live specimen in natural habitat B Oral view C Lateral view D Detail of directives showing a siphonoglyph E Cross section through proximal column F Detail of brooded juvenile G Longitudinal section through margin showing marginal sphincter muscle and marginal projection H Longitudinal section though base showing basilar muscles I Cross section through tentacle J–Y Cnidae.– marginal projection: J small basitrich K macrobasic p-mastigophore; actinopharynx: M basitrich N macrobasic p-mastigophore O microbasic p-mastigophore P long, curved basitrich; column: Q small basitrich R macrobasic p-mastigophore; filament: S small basitrich T basitrich U macrobasic p-mastigophore V microbasic b-mastigophore W microbasic p-mastigophore; tentacle: X basitrich Y spirocyst. Abbreviations.– b: brooded juvenile, bm: basilar muscle, c: column, d: directives, e: epidermis, fo: fosse, lm: longitudinal muscle, m: mesoglea, mp: marginal projection, o: oocyst, od: oral disc, pd: pedal disc, pm: parietobasilar muscle, rm: retractor muscle, s: siphonoglyph, sp: sphincter, t: tentacle, vr: verrucae, z: zooxanthellae. Scale bars: A–C: 10 mm; D–I: 200 μm; J–Y: 25 μm.

Figure 4.Mesenterial musculature and fertility of Stylobates birtlesi sp. n. holotype MTQ G57579 a mesenterial arrangement, orders indicated with Roman numerals; column wall at base of image b diffuse retractor muscle; column wall at base of image. Scale bar 1 mm.

Figure 7.Lebrunia coralligens. A Live specimen in natural habitat B Oral view C Pedal disc view D Cross section through distal column showing a siphonoglyph E Detail of retractor muscles F Detail of parietobasilar muscles G Detail of a mesentery showing oocytes and spermatic cysts H Longitudinal section through base showing basilar muscles I Cross section through tentacle J–V Cnidae.– actinopharynx: J small microbasic p-amastigopore K microbasic p-amastigophore; column: L small basitrich M small microbasic p-amastigophore; filament: N small microbasic p-amastigophore O microbasic p-amastigophore; tentacle: P basitrich Q microbasic p-amastigophore R small microbasic p-amastigophore S spirocyst; pseudotentacle: T basitrich U microbasic p-amastigophore V macrobasic p-amastigophore. Abbreviations.– bm: basilar muscle, d: directives, e: epidermis, lm: longitudinal muscle, o: oocyst, od: oral disc, pd: pedal disc, pm: parietobasilar muscle, ps: pseudotentacle, rm: retractor muscle, s: siphonoglyph, sc: spermatic cyst; t: tentacle, z: zooxanthellae. Scale bars: A–C: 10 mm; D–H: 200 μm; I: 100 μm; J–U: 25 μm; V: 20 μm.

Figure 5.Cnidae of Stylobates birtlesi sp. n. Refer to Table 1 for list of cnida types and distribution.

Figure 8.Actinoporus elegans. A Fully expanded specimen in natural habitat B Partially contracted specimen in natural habitat C Oral view D Detail of double rows of tentacles E Lateral view F Cross section through proximal column, showing retractor and parietobasilar muscles G Longitudinal section through column margin showing marginal sphincter muscle H Longitudinal section through base showing basilar muscles I Longitudinal section through tentacles J–P Cnidae.– actinopharynx: J basitrich K microbasic p-mastigophore; column: L basitrich; filament: M basitrich N microbasic p-mastigophore; tentacle: O basitrich P spirocyst. Abbreviations.– bm: basilar muscle, e: epidermis, f: filament, fo: fosse, g: gastrodermis, lm: longitudinal muscle, m: mesoglea, od: oral disc, pd: pedal disc, pm: parietobasilar muscle, rm: retractor muscle, sp: sphincter, t: tentacle, vs: vesicles. Scale bars: A–C, E: 10 mm; D: 2 mm; F–I: 200 μm; J–P: 25 μm.