Common coral predators include gastropods, polychaetes, echinoids, asteroids, pycnogonids, and fishes, such as parrotfish.
Known Predators:
Diploria labyrinthiformis has very distinct valleys that contain polyps, and deeper grooves beneath the ridges. The valleys are 5-10 mm wide, up to 6 mm deep and u-shaped in a cross section. The ridges are wider than valleys, up to 15 mm, and have a concave profile with edges 2-4 mm higher than the rest of the ridge. Right angles of the plates, or septa, make it look like there are double combs in the valleys. Crests, or costae, of the septa form across the valley walls. Grooved brain coral tends to grow to longer lengths when inhabiting shallow waters. Colonies of D. labyrinthiformis can be one to two meters in diameter. Grooved brain coral can be a variety of colors including tans, yellows, and grays.
Range length: 2 (high) m.
Other Physical Features: ectothermic ; heterothermic ; radial symmetry
The lifespan of D. labyrinthiformis is unknown. However, members of the genus Diploria are found in high abundance on Bermuda's reefs when compared to other corals. This high abundance is due to the fact that genus Diploria has lower juvenile mortality rates than other coral groups.
Grooved brain coral is in the order Scleractinia, stony corals. The optimum temperature for adult Scleractinia coral is between 25 and 29 degrees Celcius; the absolute minimal temperature is 18 degrees Celcius. Because it has a single-celled symbiotic algae within its cells, grooved brain coral needs to be at depths where light can penetrate the water. As a result, this species has a depth limit of approximately 50 meters. Diploria labyrinthiformis grows throughout the year around Bermuda and in other areas off the Carribean. This coral can live in high areas of sediments. Members of the genus Diploria are found in high abundance on Bermuda's reefs when compared to other corals. This high abundance is due to the fact that genus Diploria has lower juvenile mortality rates than other coral groups.
Range depth: 50 (high) m.
Habitat Regions: tropical ; saltwater or marine
Aquatic Biomes: reef
Grooved brain coral, Diploria labyrinthiformis, grows in the Caribbean, Bahamas, southern Florida, and Bermuda. This species tends to grow on less solid and loose substrates of the ocean floor.
Biogeographic Regions: atlantic ocean (Native )
Diploria labyrinthiformis depends primarily on suspension feeding of small marine invertebrates. This coral also has zooxanthellate algae. The symbiotic algae photosynthesize and supply the coral with nutrients and energy for calcification and growth.
Animal Foods: aquatic or marine worms; aquatic crustaceans; other marine invertebrates; zooplankton
Other Foods: microbes
Primary Diet: carnivore (Eats other marine invertebrates)
Giant brain coral serves as homes for other organisms. Grazing by Diadema antillarum, the long-spined urchin, may benefit D. labyrinthiformis by reducing macroalgal growths. Zooxanthellate algae live within the cells of D. labyrinthiformis. The single-celled algae receives protection and feeds on coral waste, while the coral receives nutrients and energy from the algae.
Ecosystem Impact: creates habitat
Mutualist Species:
There has been no research conducted on the communication and perception in D. labyrinthiformis. Many corals capture food with expanded tentacles suggesting a tactile response to the environment.
Perception Channels: tactile ; chemical
Diploria labyrinthiformis is listed as least concern on the IUCN Red List.
US Federal List: no special status
CITES: no special status
State of Michigan List: no special status
IUCN Red List of Threatened Species: least concern
Grooved brain coral has a broadcaster mode of development. Diploria labyrinthiformis is fertilized internally and then releases eggs into the ocean. The eggs hatch into swimming planktonic planulae larvae, which settle on an appropriate substrate, where asexual reproduction begins. Secondary polyps are formed, which develop to adult polyps. This species can grow at a rate of 3.5 millimeters per year.
Development - Life Cycle: metamorphosis
There are no known negative impacts of this species.
Grooved brain coral helps to make up the coral reefs that serve as diving attractions.
Positive Impacts: ecotourism
Grooved brain coral is hermaphroditic, with an annual gametogenic cycle with a 10-11 month period for gonad (sex organ) development. The typical spawning season of grooved brain coral is from late May to late June. Spawning likely begins for this species as a result of environmental cues such as high air temperature, low number of solar hours per month, low wind velocity, and initiation of the rainy season.
Grooved brain coral has an average of four mature eggs and six spermatic cysts per fertile mesentery. Eggs and spermatic cysts are located towards the aboral (opposite the mouth) part of the mesentery.
Breeding season: The breeding season is from late May to late June.
Key Reproductive Features: seasonal breeding ; sexual ; asexual ; fertilization (Internal ); oviparous
There has been no known parental care for D. labyrinthiformis. Eggs are released after they are fertilized.
Parental Investment: no parental involvement; pre-fertilization (Protecting: Female)
"It is found in the Caribbean, the Bahamas, southern Florida, and Bermuda" (Rossi -Snook, Wood, and Zeeh).
D. labyrinthiformis is in a sedimentary environment so because it can’t move around for food it has to depend on suspension to get nourishment. They prey on zooplankton and bacteria, by using their tentacles and extruded mesenterial filaments. They have nematocysts on their polyps, these nematocysts are triggered to capture and immobilize their prey. Also, mucus and cilia help in capturing and bringing food particles to the mouth (Rossi-Snook, Wood, and Zeeh). Furthermore, it also gets nourishment from symbiotic dinoflagellate algae and zooxanthellae, which is located in its polyps’ endodermal tissue layer (Rossi-Snook, Wood, and Zeeh).
The origin of the common name for the reef-forming coral, Diploria labyrinthiformis, "brain coral", is readily apparent: this species forms large clumps, 6 to 8 feet (2 to 2.5 meters) in diameter, with a deeply convoluted surface reminiscent of a human brain. It is brownish yellow in life (Voss 1980). This "brain" is actually a colony of tiny cnidarian polyps (sea anemone-like animals) that secrete a hard calcareous skeleton. The polyps feed by catching food with their tentacles, as well as obtaining nutrients from symbiotic photosynthesizing dinoflagellate "algae".
Logan and Tomascik (1991) studied the growth rate of Diploria labyrinthiformis on several high latitude coral reefs around Bermuda. Growth rates showed an inverse curvilinear relationship with depth, with highest growth rates in shallow inshore waters and lowest at the edge of the Bermuda platform and on the adjacent fore-reef slope. Annual density bands formed seasonal couplets, with narrow, high density bands appearing to form in the spring-summer months and wider, low density bands over the rest of the year . Comparison of the extension rates of D. labyrinthiformis from Bermuda with published rates from lower latitudes indicates that reefs at lower latitudes (i.e., closer to the Equator) have higher extension rates than reefs at higher latitudes (Logan et al. 1994).
The genus Diploria is a conspicuous, common, and abundant reef-building group throughout the wider Caribbean. It is endemic to (i.e., found only in) the Atlantic-Caribbean (Weil and Vargas 2010).
D. labyrinthiformis (Linnaeus 1758) form crusts, plates, and sub-massive and massive boulders along a wide depth distribution (0–35 m) and is often abundant (Weil and Vargas 2010).
Alvarado et al. (2004) studied the sexual reproduction of Diploria labyrinthiformis in Colombia and found that it is hermaphroditic (i.e., a single individual produces both eggs and sperm) and releases its gametes (eggs and sperm) in the spring, in contrast to the summer spawning of the other two Diploria species, D. strigosa and D. clivosa. Weil and Vargas (2010) studied the reproductive biology of all three species in Puerto Rico. primatily at the San Cristobal reef complex, where all three species had abundant large colonies. All three species were found to be simultaneous hermaphrodites (i.e., an individual produces both male and female gametes at the same time). Diploria strigosa and D. clivosa released gametes during August and/or September, but D. labyrinthiformis released its gametes in April and/or May (consistent with the findings of Alvarado et al. from Colombia). Of the three species, D. labyrinthiformis had the highest fecundity (an average of 36.5 eggs/polyp versus 27.2 for D. strigosa and 20.2 for D. clivosa). All three of these species are broadcast spawners, releasing their gametes into the water and providing no parental care (in some other coral species, known as brooders, fertilization and early development of larvae are internal, with larvae eventually released rather than gametes). Synchronized release of gametes (sperm and eggs) appears to be linked to lunar cycles, as well as other environmental cues.
There are three described species currently placed in the genus Diploria. In addition to D. labyrinthiformis, these are D. strigosa, which is the most common and abundant of the three and has a growth habit similar to that of D. labyrinthiformis, and D. clivosa, which is mostly sub-massive and crustose with a distribution restricted to shallow, high energy, exposed reef platforms, back reef, and rocky habitats (Weil and Vargas 2010).
Cohen et al. (2004) investigated the potential for using chemical and microstructural analysis of the skeletons of brain corals (Diploria labyrinthiformis) to provide proxy records of wintertime sea surface temperature (SST) variability in the subtropical North Atlantic. Although this species has a slow growth rate (less than one half of Pacific Porites species) and complex skeletal architecture, D. labyrinthiformis is an appealing potential archive of paleo-SST because of its abundance throughout the Caribbean; its tendency to build massive, long-lived colonies; and the presence of strong annual growth bands in the skeleton (Cohen et al. 2004).
Diploria is a monotypic genus of massive reef building stony corals in the family Mussidae.[3][4][5][6] It is represented by a single species, Diploria labyrinthiformis, commonly known as grooved brain coral and is found in the western Atlantic Ocean and Caribbean Sea.[7][2][8][9] It has a familiar, maze-like appearance.
This species of reef-building coral has a hemispherical, brain-like shape with a brown, yellow, or grey colour.[8] It has characteristic deep, interconnected double-valleys. These polyp-bearing valleys are each separated by grooved ambulacral ridges. There may be a difference in colour between the valleys and the grooves.[10]
Diploria labyrinthiformis can grow upward at a rate of approximately 3.5 millimeters per year, achieving about 2 metres (6.6 feet) in diameter. During its planktonic larval stage, the coral has locomotion. After that time, it becomes permanently sessile.[11]
This species is a suspension feeder, and survives mainly on zooplankton and bacteria. These are captured by the polyps, by extruding mesenterial filaments and tentacles. The polyps have nematocysts which are triggered to hold their prey immobile. The prey is then transported to the mouth with the assistance of mucus and cilia.[11]
Diploria labyrinthiformis is hermaphroditic, and reproduces through broadcast spawning. This entails eggs and sperm being released by adult colonies, followed by fertilization and the development of larvae at the water surface. Unlike most other Caribbean broadcast spawners, Diploria labyrinthiformis spawns over multiple months from the late spring until even mid-autumn.[12]
Diploria labyrinthiformis is found in tropical parts of the west Atlantic Ocean, the Gulf of Mexico, the Caribbean Sea, the southern tip of Florida, the Bahamas, Bermuda and the coasts of Central America.[1][2][13]
This coral occurs offshore at depths ranging from 1 to 30 metres (3.3 to 98.4 feet).[11]
Diploria labyrinthiformis hosts Zooxanthella, a symbiotic dinoflagellate alga. The alga benefits from being in a protective environment in an elevated position. The coral benefits from the nutrients produced photosynthetically by the alga which provides part of its needs for growth and calcification.[11]
The coral also has a relationship with Diadema antillarum, the long-spined urchin, whose grazing helps to reduce the effects of shading, as well as the overgrowth of macroalgae.[11]
Despite the polyps being equipped with nematocysts, various species prey upon Diploria labyrinthiformis. These include:[11]
This species is host to a parasite in the Corallovexiidae family:[2]
In the past, other species were classified as pertaining to the Diploria genus. Some of those species are now classified as Pseudodiploria, a genus erected in 2012, such as P. strigosa and P. clivosa.[14]
Images of Diploria labyrinthiformis appear on three postage stamps: a 75 cent Belizean stamp created by Georges Declercq,[15] a 15 cent stamp from United States issued 1980-08-26 and a 54 Euro cent stamp from Mayotte.[16]
Diploria is a monotypic genus of massive reef building stony corals in the family Mussidae. It is represented by a single species, Diploria labyrinthiformis, commonly known as grooved brain coral and is found in the western Atlantic Ocean and Caribbean Sea. It has a familiar, maze-like appearance.
