Nearly all of us who went through grade school in North America (and paid moderately good attention) understood symbiosis as two animals living together to the mutual benefit of both. This was a happy story and remains so in the instances where both the critters actually get something out of the relationship. For those of you who didn't pay attention, and for everyone who never bothered to dig deeper, this mutually beneficial relationship is one of three types of symbiotic behavior and falls into the category of Mutualism. There are two other kinds; one is called Parasitism, where one creature benefits and one creature is harmed (yup, think parasites like intestinal worms...) The last remaining kind is called Commensalism. This happens when one of the species benefits from the relationship, and the other is unharmed, but not benefited.
This type of relationship is very common and can sometimes be difficult to separate from the other two. For example, the fish we're highlighting today is Diademichthys lineatus. It is a tiny fish (less than two inches long at maturity) that often lives around and in between the spines of Long Spine Sea Urchins. The Urchin seemingly gets nothing from this relationship, and the fish gets protection. Where the line starts to get foggy is that the Diademichthys will also often eat little parts of the urchin called tube feet (organs that help them move, manipulate food, and even breathe). This sounds like Parasitism, but under normal circumstances, the urchin grows these back faster than they are consumed, and so is not meaningfully harmed in the long term.
his naturally leads to a couple questions, like, “what else do they eat?” Their diet actually mostly consists of inverts like little worms and copepods as well as shrimp and fish eggs. When choosing foods for them, you'll need to pick things that are nutritious and have a small bite size. Things like Gamma Rotifers, Copepods, Brine Plus Omega etc. are all good-sized foods. Nutramar Ova is an absolutely perfect food for Diademichthys lineatus as is the Nutramar Liquid Feed – Copepods. Over time you'll likely get them to take high quality, processed food and here the choice is obvious, Nutramar Marine Complete Crumbles. You'll want a tiny bite size which is achievable with the Crumbles, and really excellent nutrition, which is the calling card of all the Nutramar foods. If your specimen is hesitant to eat, you can coax them into feeding with live foods, and among these, Nutramar Live Copepods and Nutramar Live Artemia (and Nauplii) are the correct choices. Click here to learn more
This type of relationship is very common and can sometimes be difficult to separate from the other two. For example, the fish we're highlighting today is Diademichthys lineatus. It is a tiny fish (less than two inches long at maturity) that often lives around and in between the spines of Long Spine Sea Urchins. The Urchin seemingly gets nothing from this relationship, and the fish gets protection. Where the line starts to get foggy is that the Diademichthys will also often eat little parts of the urchin called tube feet (organs that help them move, manipulate food, and even breathe). This sounds like Parasitism, but under normal circumstances, the urchin grows these back faster than they are consumed, and so is not meaningfully harmed in the long term.
his naturally leads to a couple questions, like, “what else do they eat?” Their diet actually mostly consists of inverts like little worms and copepods as well as shrimp and fish eggs. When choosing foods for them, you'll need to pick things that are nutritious and have a small bite size. Things like Gamma Rotifers, Copepods, Brine Plus Omega etc. are all good-sized foods. Nutramar Ova is an absolutely perfect food for Diademichthys lineatus as is the Nutramar Liquid Feed – Copepods. Over time you'll likely get them to take high quality, processed food and here the choice is obvious, Nutramar Marine Complete Crumbles. You'll want a tiny bite size which is achievable with the Crumbles, and really excellent nutrition, which is the calling card of all the Nutramar foods. If your specimen is hesitant to eat, you can coax them into feeding with live foods, and among these, Nutramar Live Copepods and Nutramar Live Artemia (and Nauplii) are the correct choices. Click here to learn more
