Rock Flower Anemone Information and Appreciation Thread

[Mirya]

 

Common Names:

Rock flower anemone

Red beaded anemone

 

Scientific Name:

Phymanthus crucifer

 

Synonyms:

Actinia crucifera (original name granted by Le Sueur, 1817)

Epicystis crucifer (this outdated name is the one most commonly used in the hobby)

 

Natural History:

Phymanthus crucifer is a species of sea anemone native to shallow waters in the Caribbean Sea.

Distribution of locations of P. crucifer described in 21 different scientific reports. Map from Hexacorallians of the World website.

 

It is found in crevices of reef rocks and on sand flats. It either imbeds its foot deep within fissures in the rock or attaches its foot to rock several inches below the sands. In both instances, the entire column will be hidden and only the oral disk will be visible. It also camouflages itself by attaching bits of broken shells, sand and rock to the suckers on the upper part of the column. When disturbed, the anemone can retract into the crevice or sand.

 

P. crucifer contain symbiotic zooxanthellae, providing the anemone with oxygen and energy. It is hosted by Asteropotius ungellatus, a small copepod measuring approximated 1 mm in length. It is predated on by several types of sea snails belonging to the family Epitoniidae, commonly known as wentletraps.

 

Physical Characteristics:

Zoologist Addison Emery Verrill wrote an elegant description of the species in his 1907 publication The Bermuda Islands:

“When fully extended the body of the larger specimens may be 6 to 8 inches or more long and 2 to 3 inches in diameters, while the disk and tentacles may expand to the breadth of 6 to 8 inches, but specimens of about half these dimension are much more common. In full expansion the edge of the disk is usually curved into six to twelve wavy undulations, or they may become deep sinuous frills; sometimes they disappear and the broad disk is then usually concave, but changeable. Occasionally these are only four great undulations of the disk. The tentacles, which are very numerous, and form three of four crowded rows, are of moderate length, stout and tapered, but not very different in form or length. They are generally crossed by several raised, flake-white, transverse ridges or bars, usually bilobed or dilated at the ends, and containing large batteries of nematocysts.

“The disk is covered with numerous unequal radial rows of small, simple papillae or tubercles of various sizes, the rows corresponding to the tentacles of all but the out cycles. The smaller are rounded and wart-like; the larger, conical or paplliform. The column is smooth below, but has short rows of suckers, usually bright red in color, to which foreign objects adhere, on the upper part. Each row usually has 6 to 10 suckers in large specimens, decreasing in size below. The margin bears a circle of rounded acrorhagi, each one in line with a row of suckers.

“The ground color of the column is usually pale flesh-color, cream-color, or whitish, irregularly striped, streaked on flammulated with carmine, rose-red, light red, or crimson, not unlike some varieties of striped apples; near the upper margin it usually changes to gray; verrucæ bright red. The disk is elegantly variegated with several colors; the central part is often bright iridescent green, beyond which it may be variegated with lavender, russet-brown, green, yellow, and flake-white, in various patterns. Frequently the ground-color of the disk is whitish, grayish or yellowish green; while the tubercles may be darker yellow, green, olive, or brown. The basal disk is usually light red. The lips may be lavender, with white gonidial grooves; inside of mouth often pink. The tentacles also vary in colors, but usually correspond in color more or less with the disk; most commonly they are greenish or olive-brown, with the cross bars flake-white; the white cross-bars are often most numerous and most distinct on the outer tentacles.”

 

Captive Care:

P. crucifer is a hardy specimen to keep in the aquarium and is appropriate for beginner aquarists. Due to its small adult size, it is suitable for the nano aquarium. It will obtain the energy it needs from its photosynthetic zooxanthellae, but will also appreciate supplemental meaty feedings (eg Mysis shrimp). Moderate-to-bright lighting, similar in appropriateness for soft corals, will support photosynthesis. Supplemental feeding will hasten growth and is particularly recommended if aiming for reproduction.

 

Compared to other sea anemones, P. crucifer has an extremely weak sting. It is not detectable by humans. P. crucifer tends to also be much more stationary than other sea anemones. Once they settle in a place they like in the aquarium (they might travel from where they are initially placed to find this spot), they tend to remain put. P. crucifer will not host anemonefish, but they will host a variety of invertebrates, such as sexy shrimp (Thor amboinensis), anemone shrimp (Periclimenes spp.), and porcelian crabs (Neopetrolisthes spp.)

 

NOTE: Take care when treating a tank for flatworms that contains P. crucifer. Flatworms release a toxin as they die. VIP Reef reported massive losses of P. crucifer when they treated their systems for flatworms.

 

Blue spectrum lighting, particularly from LEDs, will enhance P. crucifer’s fluorescing properties, making specimens pop. Photos from Coral.

 

Reproduction:

P. crucifer at Coral Morphologic releasing sperm. For the full video go to http://coralmorphologic.com/b/2012/05/31/anemone-spawn

 

P. crucifer reproduces sexually. No confirmed reports of asexual reproduction of P. crucifer by fragging have been identified, but if anyone has a documented example, please post it. Most temperate sea anemones that reproduce sexually have an annual cycle influenced by various factors such as water temperature, sunlight intensity, lunar cycle or food availability. In Brian Jennison’s study of P. crucifer, he found a low level of gametogenesis throughout the year, with a significant increase in the spring. Dick Perrin comments in his article on captive breeding of P. crucifer that collectors of wild specimens off the Florida coast see an increase in juvenile anemones in the spring and fall, suggesting a biannual pattern.

 

Captive bred P. crucifer offspring surrounding an adult at Tropicorium.

 

P. crucifer is dioecious and exhibits a sex ratio of 1:1. Males release sperm into the water column. Coral Morphologic reports they have always witnessed spawning in the evening, between 5-6 PM. Fertilization occurs internally in the female. The female broods the young internally, up to the 6, 12, or 24 tentacle stages of development. When the young are released, they tend to settle around the disk of the female. The young will accept feeding with items such as, brine shrimp naupulii, rotifers, Cyclop-Eeze, and phytoplankton. Newly released young are colorless; color development occurs within a few weeks.

 

Left: Two newborn P. crucifer anemones attached to Valonia sp. bubble algae at the base of their mother anemone at Coral Morphologic. Right: Colorful juvenile P. crucifer captive bred at Tropicorium.

 

Nano-Reef.com Tanks Showcasing P. crucifer:

Please post below with a link to your tank thread if you would like to be added to the list.

• 1stimereefer's A Maiden's Voyage & My Rockin' Flower Garden
• DaveFason's Nano Box Flower Garden
• Frank's Nuvo 8
• Gena's You Grow Girl
• Keydiver's Psychedelic Pico 2s
• Mirya's Mini Flower Garden

 

Retail Sources:

Non-fluorescing specimens can be purchased for as inexpensively as $10. Ultra-colored, fluorescing specimens can cost in excess of $100. The following vendors have been used by Nano-Reef members in the past to purchase ultra P. crucifer specimens. If you have any other recommendations, please post them.

• KP Aquatics
• Pacific East Aquaculture
• Reef Gardener
• Aquascapers
• VIP Reef

 

References:

• Chen C, Soong K, Chen CA. The smallest oocytes among broadcast-spawning actiniarns and a unique lunar reproductive cycle in a unisexual population of the sea anemone, Aiptasia pulchella (Anthozoa: Actiniaria). Zool Stud. 2008;47: 37-45.
• Fautin, DG. Hexacorallians of the World [internet]. Lawrence (KS): University of Kansas (US); [updated 2013 Jan 2; cited 2014 Mar 8]. Available from: http://geoportal.kgs.ku.edu/hexacoral/anemone2/index.cfm
• Foord C. Anemone spawn. 2012 May 31 [cited 2014 Mar 8]. In: Morphologic Blog [internet]. Miami: Coral Morphologic. C2008- . Available from: http://coralmorphologic.com/b/2012/05/31/anemone-spawn
• Foord C. Summer solstice birthing. 2009 Jul 6 [cited 2014 Mar 8]. In: Morphologic Blog [internet]. Miami: Coral Morphologic. C2008- . Available from: http://coralmorphologic.com/b/2009/07/06/summer-solstice-birthing
• Humes AG. A review of copepoda associated with sea anemones and anemone-like forms (Cnidaria, Anthozoa). Philadelphia: American Philosophical Society; 1982.
• Jennison BL. Reproduction in three species of sea anemones from Key West, Florida. Can J Zool. 1981;59:1708-19.
• Perrin D. Captive culture of the rock anemone, Epicystis crucifer. Coral. 2012 Sep/Oct;9(5):60-8.
• Verrill AE. The Bermuda Islands Part V. New Haven: Yale; 1907.

 

Additional Reading:

Reef Hobbyist Magazine article "Rock Flower Anemonies: Breeding What Can't Be Fragged" by Miguel Tolosa in the second quarter 2015 issue.

 

 

Videos:

VIP Reef goes on a dive trip for P. crucifer. You can check out the habit these come from in the wild:

http://www.youtube.com/watch?v=TQCjSMFMgyQ

 

These videos don't apply to just P. crucifer, but are useful for any anemone owner (or potential owner).

 

First off, how to buy a good quality anemone:

http://www.youtube.com/watch?v=P3ZxGiaqWsg

 

Secondly, how to (try to) move an anemone:

http://www.youtube.com/watch?v=PXmyuw6ffMs

[MyLiquidBlue29BC]

This is great! Thank you so much. I love the videos.

[DannaM]

Great article. My favorite part is looking at the pics...maybe RF owners can post some of their favs

[Mirya]

I just added another video to the OP. It is a dive video from VIP Reef showing the native habitat of P. crucifer.

 

Now I'm contemplating if I want to add Halimeda to my own tank.

[hypostatic]

Oh wow I actually really liked those blue zoas in the beginning of the video lol

[FlowerMama]

I love that half n' half RFA starting off the thread. Pretty!

[frankdontsurf]

How long does it take a newborn RFA to become an adult? Is there a correlation to size and age?

[FlowerMama]

I don't know but I do know that 2 inch or 3 inch mamas or papas apparently can take care of the business aspect part of it. I don't know if there's a certain size the males need to be to be able to spawn but I know at least that my female is 3". You can't go by age really because some people feed more than others so you'll have different rates of growth certainly. Some barely feed at all which is a shame because they have mouths, they need meat. Originally when I had just one I was feeding once a week in the Evolve.

[frankdontsurf]

I don't know but I do know that 2 inch or 3 inch mamas or papas apparently can take care of the business aspect part of it. I don't know if there's a certain size the males need to be to be able to spawn but I know at least that my female is 3". You can't go by age really because some people feed more than others so you'll have different rates of growth certainly. Some barely feed at all which is a shame because they have mouths, they need meat. Originally when I had just one I was feeding once a week in the Evolve.

I target feed coral frenzy and fuel twice a week and mysis once. I'll add another mysis feeding a week. Muahaha fat babies!

[FlowerMama]

I have those also. I mainly put some coral frenzy fand/or reef bugs for my gorgs and anything else. And the fuel I put a teensy bit or I get spots on my glass.

[Alexraptor]

How safe are RFA's?

Will they leave cleaner shrimps, crabs and other fish alone? or is there a risk that any of them could end up as a anemonomnoms?

[Mirya]

They are very safe. They are not a hosting type of anemone, but will tolerate Sexy Shrimp walking all over them. I have not ever heard of a RFA eating a fish... maybe if you had a sick/slow moving fish like a neon goby or clown goby it could happen, but I know a few people on this forum with both of those fish in tanks with RFA with no problem.

[keydiver]

Great looking write up! Feel free to add my pico to the mix, I've got 7 ultra in there at the moment. I'll be updated ehre once I get the breeding tank setup in fall! Glad these guys are gaining their much deserved popularity

[Mirya]

Great looking write up! Feel free to add my pico to the mix, I've got 7 ultra in there at the moment. I'll be updated ehre once I get the breeding tank setup in fall! Glad these guys are gaining their much deserved popularity

 

Added your sexy nem/shroom tank!

[FlowerMama]

 

Great looking write up! Feel free to add my pico to the mix, I've got 7 ultra in there at the moment. I'll be updated ehre once I get the breeding tank setup in fall! Glad these guys are gaining their much deserved popularity

 

Yeah, title of thread. Appreciation. I appreciate nems. I'll appreciate these 3 that I have coming in on Tues!!!! I pick up my tank and stand tomorrow!!!!

 

Keydiver, aren't you excited about your tank! I'm looking forward to seeing what happens for us all. It'd be perfect if the tanks had babies in the spring. But now I question if I should have done the 60 but then again, nems are happy cuddling. It'll be one big happy family. And who knows, maybe they'll produce faster if they're touching. I'm hoping that's the case.

 

I thought this one was such a beautiful red.

 

 

 

And then further down this one's red brightness blew me away I had to have it. I see what sometimes looks like reds and they end up being orange/red. Just trying to get some stunning colors and patterns and hope that like with play-DOH red and green don't give me brown!

 

[Mirya]

 

/moan

 

I know what you mean about how some of the reds turn out to be orange. I really hope that one is RED once in your tank!

[frankdontsurf]

Pretty sure its red. The one behind it looks red but its going to be orangish in person. Nice picks 1stimereefer!

[FlowerMama]

Pretty sure its red. The one behind it looks red but its going to be orangish in person. Nice picks 1stimereefer!

 

Thanks Frankdontsurf. Like your web name. You mean the 2nd one? I know that will be orange w/ purple and I liked the contrast with the evergreen color. I have a rainbow in my 34. IF I can remove it gently I'll put it in the breeder tank as well. The last one looks like it's showing a little pink w/ the red. I just hope I'm lucky w/ some females. I've not heard of a way to sex them so I'll just hope for the best. I can only guess because this mama in my 34 opens and closes a great deal, I haven't seen the others move as much.

[gena]

Great thread, Mirya!!!!! That two-face anemone is incredible

 

Annette!!!!! those newest anemones...wow!!!!!

[FlowerMama]

Great thread, Mirya!!!!! That two-face anemone is incredible

 

Annette!!!!! those newest anemones...wow!!!!!

 

I was only going to get one red one and I really liked that one, and then I saw the other and I didn't want to decide between the two.

 

Gena, since you have mushrooms and acans which like lower light, how many inches from the sand do you have your Maxspect over your tank?

[Mirya]

When I was doing research for this thread I did find a scientific paper that was looking at a different Phymanthus species from the Pacific (it was near the Philippines IIRC). Apparently that species has a nearly translucent column so you can tell one gender from another. You can see that one gender has darker gonads than the other. Alas, the column on the RFA is too opaque to see the gonads. I wonder if you could transilluminate the column of an RFA to try to make out the gonads. (Kinda like candling an egg to see if it is fertilized.) Unfortunately, RFA have a pretty short column and would tend to collapse it if you took them out of water to examine them or lifted up their tentacles to look underneath.

[gena]

 

I was only going to get one red one and I really liked that one, and then I saw the other and I didn't want to decide between the two.

 

Gena, since you have mushrooms and acans which like lower light, how many inches from the sand do you have your Maxspect over your tank?

I never measured it. But my tank is 18" tall and I'm using the legs that came with the light.

[Mirya]

Gena, since you have mushrooms and acans which like lower light, how many inches from the sand do you have your Maxspect over your tank?

 

I just posted in the Maxspect Razor Owner's thread the results of PAR testing my Razor Nano light. I have a FTS with a measuring stick for reference int he picture too. My Razor is 7 inches off my water level and 17 inches away from my sandbed.

[hypostatic]

apreciation thread?!

 

WELL APPRECIATE THIS!

 

 

(not mine lol)

[FlowerMama]

When I was doing research for this thread I did find a scientific paper that was looking at a different Phymanthus species from the Pacific (it was near the Philippines IIRC). Apparently that species has a nearly translucent column so you can tell one gender from another. You can see that one gender has darker gonads than the other. Alas, the column on the RFA is too opaque to see the gonads. I wonder if you could transilluminate the column of an RFA to try to make out the gonads. (Kinda like candling an egg to see if it is fertilized.) Unfortunately, RFA have a pretty short column and would tend to collapse it if you took them out of water to examine them or lifted up their tentacles to look underneath.

 

Kinda funny, looking under tentacles for the gonads. I'm tired and that's just funny!!! Unfortunately, I'd still be in the same boat, buying online and then checking under the skirts. I'll just have to be surprised.

 

apreciation thread?!

 

WELL APPRECIATE THIS!

 

 

(not mine lol)

 

Yeah, I know, it's incredible. I'm so glad Mirya used that pic to start off this thread.

 

Ok, so both you Gena and Mirya have them roughly 24-25 inches from the light. My tank is 12 high. So an inch of gravel, really 11 then.