Anthopleura Elegantissima

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Phylum: Cnidaria Anthopleura elegantissima Class: Anthozoa, Hexacorallia Order: Actiniaria, Nynantheae, Thenaria (Bundodactis) Aggregating or clonal anemone Family: Endomyaria, Actiniidae

Taxonomy: Anthopleura elegantissima was skeleton and will emit water when stepped on originally described by Brandt in 1835 as (Kozloff 1983; Ricketts et al. 1985). Actinia elegantissima. The subclass Column: The column can be Zoantharia has been synonymized with twice as high as the diameter when extended, Hexacorallia (Hoeksema 2015). and is hemispherical when contracted. The entire column is covered with round verrucae Description (tubercules) in longitudinal rows (Hand 1975). Medusa: No medusa stage in Anthozoans Collar: The parapet is strong, Polyp: with a well-developed fosse (groove) (fig. 2). Size: The average diameter is about Oral Disc: The oral disc is a 2.5-4 cm, though the maximum is 5 cm large central area without tentacles on the top (Fautin and Hand 2007). Specimens are often of the column. It is broad and flat, with larger in bays than on the open coast (Hand radiating lines (mesenterial insertions). It is 1955). The illustrated specimen was 3.5 cm slightly wider than the column, or of a similar high, with a 4.5 cm disc diameter. width. The mouth is in the center of the oral Color: The tentacles are tipped with disc, and the lips may be swollen or flush with pink, purple or other colors; the illustrated the surface of disc and are not ribbed. specimen had white, green, and maroon Tentacles: There are more tentacles, and a green disc with maroon radial than 24 tentacles (Fautin and Hand 2007). lines. The column is usually green, and They are pointed, and about 1/4 as long as sometimes shades to white at the base the diameter of the disc (fig. 3). There is no (Fautin et al. 1987). The collar is green and oral inner ring of tentacles, and usually more acrorhagi are white to yellow (Fautin and than 5 orders (rows) are present. There are Hand 2007) (figs. 2, 3). Puget Sound forms no acontia (thread-like defensive structures are often pink and green (Ricketts et al. expelled through column wall). 1985). Some of the green, especially in the Mesenteries: These are tentacles, is caused by symbiotic algae cells vertical body partitions. There are from 6 in (Kozloff 1983); however, the majority of the young specimens to more than 24 pairs in coloring is from pigment cells produced by the mature adults. They are visible at high anemone to protect against UV rays. Thus, in magnification as vertical lines on column, darker habitats the greens fade until the particularly near the base, and can be anemone is white (Fautin and Hand 2007). irregular, due to asexual fission (not shown). Body: The anemone has a strong Pedal Disc: This species has collar, broad flat disc, and slender pointed a well-developed pedal disc that attaches to tentacles. The column has longitudinal rows the substrate. Its shape varies from circular to of tubercules, which are adhesive and create very irregular (Hand 1955). The base is a layer of attached shells and debris. Body usually the same diameter as column. There walls are soft and thin (Haderlie et al. 1980). are no physa (bulbs) at the base. The column has a groove below the tentacles Cnidae: There are several kinds of (fosse) covered by a distinct fold (parapet or cnidae in the tentacles, column, acrorhagi, collar). The anemone becomes a hemispheric actinopharynx and filaments (not shown); see glob when contracted (fig. 3), and blends into Metridium (Hand 1955). its rocky intertidal habitat. It has a hydrostatic

A publication of the University of Oregon Libraries and the Oregon Institute of Marine Biology Individual species: http://hdl.handle.net/1794/12639 and full 3rd edition: http://hdl.handle.net/1794/18839 Email corrections to: [email protected] Acrorhagi: Also known as spherules, that A. elegantissima is clonal while A. sola is these fighting tentacles are round, hollow solitary. Though A. sola is not found locally, bodies covered with nematocysts. They are there are many examples in the literature of inconspicuous at the top of the column just A. sola being misclassified as A. outside the tentacles (fig. 2) (Hand 1955). elegantissima (Pearse and Francis 2000). Verrucae: These are simple, circular Other sand-dwelling anemones might include tubercules (Fautin and Hand 2007). They are Flosmaris grandis, a southern form, which is adherent, and collect gravel, shell, and debris. vermiform and has a translucent or white This layer helps prevent desiccation and column (Fautin and Hand 2007). Most other protects the anemone from UV rays elongated or tube-dwelling forms, i.e., Order (MacGinitie and MacGinitie 1968; Ricketts et Cerinatharia, are rarely intertidal in our area. al. 1985). Verrucae on the collar are forked and compound (see A. artemisia, fig. 3 in this Ecological Information guide). Those on the column are arranged in Range: The type locality is Sitka (Sitchae distinct longitudinal rows, are not densely Islands), Alaska (Brandt 1835). The range is packed, and become fewer toward the base Alaska to southern California. ("limbus") (Hand 1955; Fautin and Hand Local Distribution: In Coos Bay, they can be 2007). There are many cinclides (temporary found in high abundance at Pigeon Point. or permanent pores at tips of verrucae) on the Habitat: Specimens are found on rocky column (fig. 4). substrates in the mid to high intertidal, often in full sun, where it aggregates in beds of up to Possible Misidentifications 20 m and 100,000 animals (Childress 1969; The genus Anthopleura can be distinguished Fautin and Hand 2007). They are especially from other estuarine anemones (Metridium, prevalent in exposed-rocky habitats where Diadumene) by their acrorhagi inside the sand collects, and are more occasional on fosse under the tentacles, and by the open coasts and exposed pilings (Ricketts et verrucae on their columns. Anthopleura al. 1985). When found in sand, A. always have a well-developed pedal disc and elegantissima is attached to underlying rock, a flat, oral disc with a clear central area. and can be fully buried at times (Fautin and Two other species of Anthopleura occur in Hand 2007). Algae mats in the intertidal this area: Anthopleura xanthogrammica is a create hospitable, moist habitats for the large open coast species occasionally found aggregations (Niesen 2007). Specimens can in the most marine parts of our estuaries. It is survive in polluted waters (Ricketts et al. very large, solitary (not aggregating), with 1985), and can hang from the roof of uniformly colored disc and tentacles (not pink- overhangs (Niesen 2007). tipped or with radial lines on the disc). The Salinity: Collected at 30. tentacles are in 5 or more rows (Haderlie et Temperature: Specimens are kept in lab at al. 1980). Its verrucae completely cover the 12°C. 20°C is considered high temperature column (they are not in rows). Anthopleura and causes cnidarian bleaching (loss of artemisia has tubercules on the upper 2/3 of symbiotic algae) (Richier et al. 2008). its column only; the column is white or pink Tidal Level: Found from 0 to +4.5 feet above below and usually gray or black above; mean lower low water level (Hand 1955). tentacles are brightly colored and patterned Associates: Green algae (zoochlorellae) and (red in Coos Bay). Anthopleura artemisia is dinoflagellates (zooxanthellae) live in the more likely to be found burrowing in a sandy anemone’s gut tissue and create some of the or muddy substrate than A. elegantissima, green coloring; the algae provide some which can live close by. It also lacks the algae nutritional value to their host, though the symbionts that are found in A. elegantissima. anemone still requires carnivorous meals A third species of Anthopleura, A. sola, is very (Ricketts et al. 1985; Kozloff 1983). The similar in appearance to A. elegantissima. amphipod Orchomenella recondita sometimes The primary difference between the two is lives in the digestive cavity. Many organisms,

Piazzola, C.D. and T.C. Hiebert. 2015. Anthopleura elegantissima. In: Oregon Estuarine Invertebrates: Rudys' Illustrated Guide to Common Species, 3rd ed. T.C. Hiebert, B.A. Butler and A.L. Shanks (eds.). University of Oregon Libraries and Oregon Institute of Marine Biology, Charleston, OR. including the amphipods Gibberosus myersi lower to the tidepools as they grow (Sebens and Macronassa macromera, the snail 1982b). Epitonium tinctum, and the chiton Longevity: These anemones are reputed to Lepidochitona fernaldi, live in the be very long lived, and are especially aggregations (Chapman 2007; McLean 2007; successful as an aquarium animal (one Strathmann and Eernisse 1987). particular specimen died after about 80 years Abundance: Anthopleura elegantissima is due to lab failure rather than old age) the most abundant anemone on the coast (Ricketts et al. 1985). (Ricketts et al. 1985), and is the most Growth Rate: Specimens reach adult size abundant Anthopleura in Coos Bay. The peak two years after settlement (Sebens 1982b; of the breeding season is Sept-Oct, and Fautin and Sebens 1987). The highest growth recruitment is late fall-winter (Fautin and rate is concurrent with the lowest clonal Sebens 1987). division rate in the spring and summer, while the highest division rate and lowest growth rate both occur in the fall and winter (Sebens Life-History Information 1982a). Reproduction: There are both sexual and Food: Anthopleura elegantissima is a asexual reproductive cycles. Individual polyps carnivorous stationary hunter in the tidepools and clonal aggregations are dioecious (Fautin (Niesen 2007) that uses tentacles to capture and Sebens 1987). Sexual spawning is in prey (Ricketts et al. 1985). It primarily eats September (San Francisco) (Haderlie et al. crustaceans, such as copepods, amphipods, 1980). Eggs are freely-spawned and brown, and isopods (Haderlie et al. 1980). Food no larger than 250 µm (Sadro 2001), and preference seems to be genetically covered with clusters of spines (Fautin and determined (Waters 1975). Sebens 1987). Asexually, anemones divide Predators: Specimens are eaten by varied via longitudinal binary fission, producing intertidal predators, including seastars. The aggregations of "clones" common to this nudibranchs Aeolidia papillosa and species (all are similar in coloration and sex) Hermissenda crassicornis attack the column (Hand 1955; Fautin and Hand 2007). Each (McDonald 2007; Ricketts et al. 1985). The division takes about two days to complete, snail Epitonium tinctum eats the tips of and only the outer edge of the clonal colony tentacles (McLean 2007). divides by fission (MacGinitie and MacGinitie Behavior: Anemones at the edges of clonal 1968). groups will "attack" neighboring clonal Larva: Sexual reproduction produces feeding aggregations with their acrorhagi, causing planula larvae. At three weeks larvae are wounds; a corridor between clonal groups is ovaloid to cylindrical, covered in cilia, and no thus maintained (Francis 1973; Ricketts et al. longer than 250 µm with a 70 µm apical tuft. 1985). Symbiotic green algae may aid the They actively swim using the cilia on their anemone in modifying phototaxis apical tuft (Sadro 2001; Siebert 1974). They (Buchsbaum 1968) and in averting starvation feed by releasing a mucus strand as they (Kozloff 1983). Anemones contract, inflate, swim. The strand collects food particles, and and expel nematocysts or detach their pedal the cilia then pull the strand up to the mouth disc and move when their column is attacked and ingest it (Siebert 1974). There are no by the nudibranch Aeolidia papillosa (Waters symbiotic algae in the larvae; this relationship 1975). between algae and A. elegantissima must be established at a later life stage (Siebert 1974). Bibliography Juvenile: Anemones are considered juveniles if they are less than 6.5 cm in 1. BRANDT, J. F. 1835. Prodromus diameter (Sebens 1982b). They are common descriptionis animalium ab H. in intertidal mussel beds and less common Mertensio in orbis terrarum but present in rock crevices. It is possible that circumnavigatione observatorum. they settle higher in the intertidal and migrate Google eBooks, Petropoli.

A publication of the University of Oregon Libraries and the Oregon Institute of Marine Biology Individual species: http://hdl.handle.net/1794/12639 and full 3rd edition: http://hdl.handle.net/1794/18839 Email corrections to: [email protected] 2. BUCHSBAUM, V. M. 1968. Behavioral Haderlie (eds.). Stanford University and physiological responses to light by Press, Stanford. the sea anemone Anthopleura 10. HAND, C. H. 1955. The sea elegantissima as related to its algal anemones of central California. Part II. symbiotes. PhD. Stanford University. The endomyarian and mesomyaroan 3. CHAPMAN, J. W., E. L. BOUSFIELD, anemones. Wasmann Journal of and D. E. BOWERS. 2007. Biology. 13:37-99. Amphipoda: Gammaridea, p. 545-618. 11. —. 1975. Class Anthozoa, p. 85-93. In: The Light and Smith manual: In: Light's manual: intertidal intertidal invertebrates from central invertebrates of the central California California to Oregon. J. T. Carlton coast. S. F. Light, R. I. Smith, and J. T. (ed.). University of California Press, Carlton (eds.). University of California Berkeley, CA. Press, Berkeley. 4. CHILDRESS, L. F. 1969. Intra-specific 12. HOEKSEMA, B. 2015. Hexacorallia. aggression and its relation to the Vol. 2015, World Register of Marine distribution pattern of the clonal sea Species: anemone, Anthopleura elegantissima. http://www.marinespecies.org/aphia.p Ph.D. Stanford University. hp?p=taxdetails&id=1340. [Accessed 5. FAUTIN, D. G., and C. HAND. 2007. 9/23/2015]. Anthozoa, p. 173-184. In: The Light 13. KOZLOFF, E. N. 1983. Seashore life and Smith Manual: intertidal of the northern Pacific coast. invertebrates from central California to University of Washington Press, Oregon. J. T. Carlton (ed.). University Seattle. of California Press, Berkeley. 14. MACGINITIE, G. E., and N. 6. FAUTIN, D. G., and K. P. SEBENS. MACGINITIE. 1968. Natural history of 1987. Phylum Cnidaria, Class marine animals. McGraw-Hill Book Anthozoa, p. 83-104. In: Reproduction Co., New York. and development of marine 15. MCDONALD, G. R. 2007. Sacoglossa invertebrates of the northern Pacific and Nudibranchia, p. 788-807. In: The coast. M. F. Strathmann (ed.). Light and Smith manual: intertidal University of Washington Press, invertebrates from central California to Seattle. Oregon. J. T. Carlton (ed.). University 7. FAUTIN, D. G., A. E. SIEBERT, and of California Press, Berkeley, CA. E. N. KOZLOFF. 1987. Class 16. MCLEAN, J. H. 2007. Gastropoda, p. Anthozoa, p. 68-78. In: Marine 713-739. In: The Light and Smith invertebrates of the Pacific Northwest. manual: intertidal invertebrates from E. N. Kozloff (ed.). University of central California to Oregon. J. T. Washington Press, Seattle. Carlton (ed.). University of California 8. FRANCIS, L. 1973. Intraspecific Press, Berkeley, CA. aggression and its effect on the 17. NIESEN, T. M. 2007. Intertidal distribution of Anthopleura habitats and marine biogeography of elegantissima and some related sea the Oregonian Province, p. 3-17. In: anemones. Biological Bulletin. 144:73- The Light and Smith manual: intertidal 92. invertebrates from central California to 9. HADERLIE, E. C., C. HAND, and W. Oregon. J. T. Carlton (ed.). University B. GLADFELTER. 1980. Cnidaria of California Press, Berkeley, CA. (Coelenterata): the sea anemones and 18. PEARSE, V., and L. FRANCIS. 2000. allies, p. 40-75. In: Intertidal Anthopleura sola, a new species, invertebrates of California. R. H. solitary sibling species to the Morris, D. P. Abbott, and E. C. aggregating sea anemone, A. elegantissima (Cnidaria: Anthozoa: