Fascinating Reproduction in Open Brain Coral:
An Aquarium Report on Trachyphyllia Geoffroyi.
BY: Steven Pro and Anthony Calfo.
Recently thought to include two genera, the family Trachyphyllidae is represented by two forms in the genus Trachyphyllia that aquarists will recognize. Formerly described as separate genera, known as "Open Brain" corals. Some popular literature does distinguish between the two forms as representing separate species within the genus Trachypllia. The authors make little distinction between the animals for the purpose of this report. T. geoffroyi predominantly represents this genus in captivity. T. radiata forms appear less commonly in imports. While similar in gross appearance these two forms may have differences in their origins on the reef and subsequent captive requirements that lend to the morphological distinctions, even if not to speciation. The exact taxonomic classification of the animal is of little matter to most aquarists and is admittedly beyond the scope of the authors. This report describes the husbandry and fascinating asexual reproductive strategy of Trachyphyllia through decalcification to produce daughter colonies.
BASIC HUSBANDRY FOR TRACHYPHYLLIA
We begin first with a bit of history and general information on Trachyphyllia for improved care in reef aquariology. T. geoffroyi is a free-living animal at maturity and can be found in lagoons and protected margins of the reef buried in sand or muddy substrates. They should always be maintained as such in display. The conical skeleton of this species has evolved to serve this very orientation specifically. Placement of these animals upon rocky substrates can sometimes lead to abraded tissue from daily polyp cycles (expansion and contraction) or displacement when a inflated animal becomes imbalanced. Damage tot he tissue of Trachyphyllids is not especially quick to heal and is often hampered by infection or predation. Fish, shrimp, crabs, and worms are often attracted to injured Trachyphyllia to graze upon infected tissue or prey on the vulnerable animal altogether.
Trachyphyllia commonly occur in moderately deep and clear waters and do not seem to be as well adapted at removing sediment as other free-living corals on soft substrates like the fungiids, for example. This can be a problem in aquaria with inadequate water flow or active tank mates such as sand-shifting gobies that deposit sediment upon Trachyphyllia. Moderate water flow is recommended to remove lingering sediments, although caution should be exercised to avoid too much that will compromise their mucous net feeding strategy. Ultimately, Trachphyllia are exceptionally adaptable to a wide range of water flow if sedimentation is not a concern.
With the exception of intense metal halide lighting over shallow aquaria. Trachyphyllia species have proven to be quite adaptive to a wide range of aquarium lighting. Artificial illumination favoring the blue end of the spectrum is recommended for deeper water specimens. T. geoffroyi occurs in a range of color from red through brown to green. Red and brown specimens come from deeper waters and seem to require less light, while brightly reflective green individuals are the most tolerant of bright light, hailing from UV light, clear, less deep waters. Pale-colored specimens, such as pink or yellow, are not healthy animals but merely stressed corals that have "bleached" (specifically, they have aborted a significant amount of zooxanthellae). In time, if the animal survives the event of stress proper pigmentation may return. Without supplemental feeding, however, most bleached animals die from attrition.
Trachytphyllia are active feeders and are able to accept larger zooplankton than most corals. Their large feeding tentacles come out at night as most corals do that favor zooplankton. Feeding at other times of the day may be possible by the introduction of a stimulant such as the thawed "juice" from frozen ocean meats (shrimp and krill work well, fifteen minutes prior to feeding). Finely shredded meats or whole prey of marine origin like pacifica plankton and mysid shrimp are very good fare. Avoid feeding zooplankton substitutes larger than 1/2" in size. Inappropriately large food items may be accepted by the animal but are usually regurgitated later in the form of floating mucosal rafts. In time, the animal may starve under the care of an aquarist that thought such large chunks of food were being digested. Trachyphyllias have been observed, like other free living corals such as fungiids, to feed with a mucosal "net" and they are known to swell to an impressive size as part of the feeding strategy. Some aquarists have noticed Trachyphyllia specimens also shrinking over time and taking on a "skin and bones" appearance. Inadequate feeding has been implicated4ed in this phenomenon. Trachyphyllia species are not autotrophic animals to say the least. They cannot survive on the products of symbiosis alone. At minimum, open brain corals should be fed several time per week. More food may be neccessary for growth.
With significantly less representation in captivity than T. geoffroyi, husbandry for the "T. radiata" form is not as clearly defined although it is sure to be similar if not the same (with consideration for their synonymy). Unlike T. geoffroyi, "T. radiata" forms are not considered to be only free living animals. It is said to be common in deeper water than T. geoffroyi and attached to hard substrates. One interesting theory about the heavily iridescent bright green coloration of "T. radiata" (AKA "metal dome" open brain coral) is that such pigmentation may be used to refract and simplify the weakly available light in said deep water. Contrary to the common belief that many corals proteins serve predominantly to reflect UV intense light away, some proteins are instead found below the zooxanthellae and serve to reflect light back to the symbiotic algae (Borneman, pers. comm.) This is consistent with anecdotal observations by many aquarists that the "metal dome" or "metallic" open brain coral favors weaker illumination (especially on import). Yet other aquarists have also reported the form to be quite hardy and tolerant of bright light with proper acclimation. Beyond the obvious explanation that such contrasts can be described by the collection of specimens over a wide range on the reef, Trachyhyllia species have long since demonstrated great hardiness and adaptability in captivity, including remarkable photoadaptation. Placement of the hemispherical "T. radiata" type animal upon a hard substrate or reef proper may be equally acceptable with due consideration for acclimation to new, captive lighting. "T. radiata" forms are easily distinguished from T. geoffroyi in most cases. The corallum of T. geoffroyi is generally cone shaped (flabello-meandroid) while that of T. radiata is flat bottomed (hemispherical. "T. radiata"{ is also likely to be more convoluted in form while T. geoffroyi might be described as simple, fused lobes.
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An Aquarium Report on Trachyphyllia Geoffroyi.
BY: Steven Pro and Anthony Calfo.
Recently thought to include two genera, the family Trachyphyllidae is represented by two forms in the genus Trachyphyllia that aquarists will recognize. Formerly described as separate genera, known as "Open Brain" corals. Some popular literature does distinguish between the two forms as representing separate species within the genus Trachypllia. The authors make little distinction between the animals for the purpose of this report. T. geoffroyi predominantly represents this genus in captivity. T. radiata forms appear less commonly in imports. While similar in gross appearance these two forms may have differences in their origins on the reef and subsequent captive requirements that lend to the morphological distinctions, even if not to speciation. The exact taxonomic classification of the animal is of little matter to most aquarists and is admittedly beyond the scope of the authors. This report describes the husbandry and fascinating asexual reproductive strategy of Trachyphyllia through decalcification to produce daughter colonies.
BASIC HUSBANDRY FOR TRACHYPHYLLIA
We begin first with a bit of history and general information on Trachyphyllia for improved care in reef aquariology. T. geoffroyi is a free-living animal at maturity and can be found in lagoons and protected margins of the reef buried in sand or muddy substrates. They should always be maintained as such in display. The conical skeleton of this species has evolved to serve this very orientation specifically. Placement of these animals upon rocky substrates can sometimes lead to abraded tissue from daily polyp cycles (expansion and contraction) or displacement when a inflated animal becomes imbalanced. Damage tot he tissue of Trachyphyllids is not especially quick to heal and is often hampered by infection or predation. Fish, shrimp, crabs, and worms are often attracted to injured Trachyphyllia to graze upon infected tissue or prey on the vulnerable animal altogether.
Trachyphyllia commonly occur in moderately deep and clear waters and do not seem to be as well adapted at removing sediment as other free-living corals on soft substrates like the fungiids, for example. This can be a problem in aquaria with inadequate water flow or active tank mates such as sand-shifting gobies that deposit sediment upon Trachyphyllia. Moderate water flow is recommended to remove lingering sediments, although caution should be exercised to avoid too much that will compromise their mucous net feeding strategy. Ultimately, Trachphyllia are exceptionally adaptable to a wide range of water flow if sedimentation is not a concern.
With the exception of intense metal halide lighting over shallow aquaria. Trachyphyllia species have proven to be quite adaptive to a wide range of aquarium lighting. Artificial illumination favoring the blue end of the spectrum is recommended for deeper water specimens. T. geoffroyi occurs in a range of color from red through brown to green. Red and brown specimens come from deeper waters and seem to require less light, while brightly reflective green individuals are the most tolerant of bright light, hailing from UV light, clear, less deep waters. Pale-colored specimens, such as pink or yellow, are not healthy animals but merely stressed corals that have "bleached" (specifically, they have aborted a significant amount of zooxanthellae). In time, if the animal survives the event of stress proper pigmentation may return. Without supplemental feeding, however, most bleached animals die from attrition.
Trachytphyllia are active feeders and are able to accept larger zooplankton than most corals. Their large feeding tentacles come out at night as most corals do that favor zooplankton. Feeding at other times of the day may be possible by the introduction of a stimulant such as the thawed "juice" from frozen ocean meats (shrimp and krill work well, fifteen minutes prior to feeding). Finely shredded meats or whole prey of marine origin like pacifica plankton and mysid shrimp are very good fare. Avoid feeding zooplankton substitutes larger than 1/2" in size. Inappropriately large food items may be accepted by the animal but are usually regurgitated later in the form of floating mucosal rafts. In time, the animal may starve under the care of an aquarist that thought such large chunks of food were being digested. Trachyphyllias have been observed, like other free living corals such as fungiids, to feed with a mucosal "net" and they are known to swell to an impressive size as part of the feeding strategy. Some aquarists have noticed Trachyphyllia specimens also shrinking over time and taking on a "skin and bones" appearance. Inadequate feeding has been implicated4ed in this phenomenon. Trachyphyllia species are not autotrophic animals to say the least. They cannot survive on the products of symbiosis alone. At minimum, open brain corals should be fed several time per week. More food may be neccessary for growth.
With significantly less representation in captivity than T. geoffroyi, husbandry for the "T. radiata" form is not as clearly defined although it is sure to be similar if not the same (with consideration for their synonymy). Unlike T. geoffroyi, "T. radiata" forms are not considered to be only free living animals. It is said to be common in deeper water than T. geoffroyi and attached to hard substrates. One interesting theory about the heavily iridescent bright green coloration of "T. radiata" (AKA "metal dome" open brain coral) is that such pigmentation may be used to refract and simplify the weakly available light in said deep water. Contrary to the common belief that many corals proteins serve predominantly to reflect UV intense light away, some proteins are instead found below the zooxanthellae and serve to reflect light back to the symbiotic algae (Borneman, pers. comm.) This is consistent with anecdotal observations by many aquarists that the "metal dome" or "metallic" open brain coral favors weaker illumination (especially on import). Yet other aquarists have also reported the form to be quite hardy and tolerant of bright light with proper acclimation. Beyond the obvious explanation that such contrasts can be described by the collection of specimens over a wide range on the reef, Trachyhyllia species have long since demonstrated great hardiness and adaptability in captivity, including remarkable photoadaptation. Placement of the hemispherical "T. radiata" type animal upon a hard substrate or reef proper may be equally acceptable with due consideration for acclimation to new, captive lighting. "T. radiata" forms are easily distinguished from T. geoffroyi in most cases. The corallum of T. geoffroyi is generally cone shaped (flabello-meandroid) while that of T. radiata is flat bottomed (hemispherical. "T. radiata"{ is also likely to be more convoluted in form while T. geoffroyi might be described as simple, fused lobes.
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