AEFW or Acro-Eating Starfish?

[killergoby]

About 1 month ago, I noticed that a colony of Ponape Rainbow that I had been nursing back to health due to a shipping issue and a JF Fox Flame, both next to each other on the frag rack, looked to be in poor condition. The Ponape Rainbow had lost a lot of tissue around the base following 3.5 days in a shipping bag but the color had returned and the polyps were out. New growth was seen filling in the tips which had come in burnt and were previously bitten by a Flame Angel that I rehomed. However, there was still exposed white skeleton at the base of the coral which looked to have progressed a bit on one branch of the frag. The Fox Flame had clear bite marks (seen in images below). For the previous 7-10 days there had been a black/white mottled asterina-sized starfish which I believe came in on some Caribbean live rock and eventually hitched its way from my refugium when I moved some rocks between the tanks. I turkey basted both corals but observed no flatworms. I removed both frags, the starfish went into the trash, and I placed the frags into the refugium away from any other SPS for observation. I placed them in the refugium December 15th. Both corals have grown in the refugium and look to be healthy again with no signs of any bite marks. Any basting I have done on them or my other colonies has never returned any flatworms, and even dips and other rinses in a specimen container of the frags did not return any culprits. I have no proof of AEFW, only the bite marks on the Fox Flame and the recession around the base of the Ponape Rainbow as reason for suspicion. Could this be a starfish eating on my acropora or is it AEFW and I haven't been able to find one yet by sheer bad luck?

For reference, my GC Acroberry, BC no namer, Green Slimer, Sunset Milli, other frags of the Ponape Rainbow, and Cali Tort in the same aquarium have all grown and shown no issues. All my other SPS have had no issues either.
(Image of similarly appearing starfish from the internet attached)

 

[ScottB]

About 1 month ago, I noticed that a colony of Ponape Rainbow that I had been nursing back to health due to a shipping issue and a JF Fox Flame, both next to each other on the frag rack, looked to be in poor condition. The Ponape Rainbow had lost a lot of tissue around the base following 3.5 days in a shipping bag but the color had returned and the polyps were out. New growth was seen filling in the tips which had come in burnt and were previously bitten by a Flame Angel that I rehomed. However, there was still exposed white skeleton at the base of the coral which looked to have progressed a bit on one branch of the frag. The Fox Flame had clear bite marks (seen in images below). For the previous 7-10 days there had been a black/white mottled asterina-sized starfish which I believe came in on some Caribbean live rock and eventually hitched its way from my refugium when I moved some rocks between the tanks. I turkey basted both corals but observed no flatworms. I removed both frags, the starfish went into the trash, and I placed the frags into the refugium away from any other SPS for observation. I placed them in the refugium December 15th. Both corals have grown in the refugium and look to be healthy again with no signs of any bite marks. Any basting I have done on them or my other colonies has never returned any flatworms, and even dips and other rinses in a specimen container of the frags did not return any culprits. I have no proof of AEFW, only the bite marks on the Fox Flame and the recession around the base of the Ponape Rainbow as reason for suspicion. Could this be a starfish eating on my acropora or is it AEFW and I haven't been able to find one yet by sheer bad luck?

For reference, my GC Acroberry, BC no namer, Green Slimer, Sunset Milli, other frags of the Ponape Rainbow, and Cali Tort in the same aquarium have all grown and shown no issues. All my other SPS have had no issues either.
(Image of similarly appearing starfish from the internet attached)

I've had a flavor of asterina that went rogue on zoanthids, but on acropora would be new info.

What did you dip in? KCl works instantly on worms. But most dips will get them moving/releasing eventually.

If only the "new to you" pieces are showing signs of stress, it could simply be stress and not parasites.

 

[ISpeakForTheSeas]

I've heard some species eat corals and others don't - I've seen convincing evidence for one species (a very darkly colored one), and one piece of somewhat convincing evidence for one different species, but the vast majority of these guys seem to be at least mostly safe.

With regards to whether or not the average "Asterina" (technically Aquilonastra - Asterina is a separate genus within the Asterinidae family) eat corals, it might be a species specific thing, it might be a you have way too many starfish so they're out of other food options thing, it might be they're eating the slime coat/mucus on the coral rather than the coral itself (see below), or they might just opportunistically eat unhealthy corals. Based on how starfish eat, it seems plausible to me that it may also be coincidental (i.e. the star goes to eat something off the coral and the coral just happens to be one that is able to be negatively effected by the star's everted stomach). Regardless, Zoas are just about the only coral I've heard about regular "Asterina" stars potentially going after (on rare occasion, I've heard about them going for other corals - such as a birdsnest coral - but it is about as common as tangs going for corals).

A quote I like to refer to for this:

Timfish said:
It's an Aquilonastra spp. starfish and is a great scavenger. I see them with anywhere from 4 to 12 legs. The whole discusion around them seems to me excellent examples of misidentification, mistaken behaviour and assumed causality based just on heresay without looking at the research. Asterina spp starfish are preditary but only reproduce sexually and are shortlived so while it's possible some might get into a tank even if it did happen it's not going to be around long. Aquilonastra are one of the uncommon species that reproduce fissiparous or by splitting so are easy to identify by the different sized legs regrown after splitting. They perform an important function not only feeding off algae films but also feeding off microbial films including those on corals (at least ones that don't sting). FYI the mucus coating on corals ages and corals have to periodicely shed it to renew it and maintian healthy microbial processes (Ref 1, Ref 2). If Aquilonastra are feeding on zoas or softies I'll argue they are either benign or even beneficial as they may be reducing the unhealthy older mucus which can be full of unhealthy microbes which the animal is trying to get rid of and are far more likely to be the actual problem.

Here's an example, this Toadstool is doing one of it's periodic sheddings. The Aquilonastra have been in this system for years but only climb onto the Toadstool when it's shedding. In the first picture you can see the old mucus film, Aquilonastra starfish and areas they have cleaned off. The second picture shows the Toadstool a week later.

 

[killergoby]

The Fox Flame had been in the tank since November 10th and then took a sudden nose dive before I relegated it to the refugium, and the Ponape Rainbow frag was shipped at the beginning of October and all the frags in that shipment have had a very slow return to life after the shipping mishap. I only add this information because the "new to me" frags theory seems quite delayed to only be stress and my worry is always parasites. Perhaps it is just a delayed reaction to a tank change that the other acros weathered just fine, or really really long term reaction to adjusting in the tank.

With regards to these frags, if they have grown in size and healed up nicely in the refugium, and I have not been able to baste any flatworms off of them and there is no exposed dead tissue, would it be safe to try to reintroduce them to the frag rack in my main tank at least? Maybe with a dip in between? I don't want to run the risk of AEFW although I feel i've been pretty careful, but the apparent bite marks a month ago made me very worried.

 

[Lavey29]

Put a 6 line wrasse in the tank and sleep comfortably knowing death is being unleashed on any tank pests

 

[AlexandraDreadlocksPanda]

I think it’s probably just eating the necrotic tissue, or bio film that’s formed because of the dead tissue… I’ve had them eat Zoa’s but never Acro’s…