Echinometra lucunterrock boring urchin

Geographic Range

Rock-boring urchins are distributed throughout the Caribbean and coastal South Atlantic subtropical region, from Bermuda through southern Florida and the islands of the Caribbean (particularly Barbados) to Desterra, Brazil. (Lewis and Storey, 1984; McPherson, 1969)


This urchin is typically found in shallow waters of 0-2 meters and has been reported at depths up to 45 meters. It is most abundant on tidal terraces and rocky shores in areas of high energy waves and on shallow coral reefs within rock crevices, and may be present (though less commonly found) on sandy bottoms. (Abbott, et al., 1974; Weintraub, 2012)

  • Range depth
    0 to 45 m
    0.00 to 147.64 ft

Physical Description

This species has an elliptical shape with 100 to 150 colored spines on the arboral surface. Size at maturity is typically 40 mm in diameter or smaller, although some individuals recorded larger than 150 mm have been recorded. Test color is variable between individuals, ranging between a black, brown, green or dark blue color with lighter colors on the arboral surface. In some cases the apical system of the test is bright red, with black spines. This species is differentiated from other closely related species by having fewer pore-pairs per arc, fewer ambulacral and interambulacral plates, a different apical system, and slender, tridentate pedicellariae. Like all other echinoids, it has 5 teeth located within a specialized feeding apparatus known as Aristotle's lantern. As with many urchins, this species' spines are venomous. (Abbott, et al., 1974; Blevins and Johnsen, 2004; Jackson, 1912; Lewis and Storey, 1984; McPherson, 1969; Weintraub, 2012)

  • Sexual Dimorphism
  • sexes alike
  • Range length
    40 to 150 mm
    1.57 to 5.91 in


Post-fertilization, zygotes undergo first cleavage after approximately 90 minutes. Planktonic larvae develop in several stages, including the blastula (reached at the 128 cell stage), gastrula (1000 cell stage), and prism stages. The following stage, four-armed pluteus, is reached after the second day of fertilization. Following the fourth day, posterodorsal arms appear and full metamorphosis occurs approximately 19 days after fertilization. This urchin is a slow-growing and relatively long-lived echinoid species with a life expectancy over 10 years. (Abbott, et al., 1974; Bolton and Florence I.M., 2002; Conway, et al., 1984; Ebert, et al., 2008; Lewis and Storey, 1984; McPherson, 1969)


This species is usually found in dense aggregations. Spawning occurs once or twice (depending on individual conditions) in the summer. Individuals release their gametes into the water column, with males usually spawning before females. This may act as a cue, stimulating females to release eggs. (Abbott, et al., 1974; Grünbaum, et al., 1978; Lewis and Storey, 1984)

Sexual maturity occurs when individuals reach a test diameter of at least 20 mm and when ripe sex cells are present in the gonads. Gonad development occurs most often during spring, with spawning occuring in the summer, usually once but in some cases twice per year. The gonadal index (number of sex cells/unit of gonad tissue) is highest during summer. The gametogenic cycle comprises 5 different stages: proliferative, premature, mature, depleted, and resting. Release of the male’s spermatozoa elicits release of oocytes by females. Spawning may also occur during other times of the year outside of summer, depending primarily on hydrodynamics and nutrient availability. There is currently no published information noting the average number of offspring, gestation period, and birth mass for this species. (Abbott, et al., 1974; Lima, et al., 2009; McPherson, 1969)

  • Breeding interval
    Typically once per year; occasionally twice per year
  • Breeding season

This species exhibits no parental investment after gamete release. Zygotes become planktonic larvae and drift unattended until they develop into the benthic adult form. (Abbott, et al., 1974; Lewis and Storey, 1984; McPherson, 1969)

  • Parental Investment
  • no parental involvement


Rock-boring urchins exhibit a slow growth rate. After completing their first year of life, average life expectancy is over 10 years. However, there have been no detailed studies documenting the average lifespan in the wild, and estimated lifespans in captive individuals are unknown. (Abbott, et al., 1974; Ebert, et al., 2008)

  • Average lifespan
    Status: wild
    10 years


This species uses its tube feet to attach itself to rocky surfaces and it has the ability to create its own burrows. Most movements occur during dark hours, when urchins move out of crevices and rock burrows to feed, primarily on algae, and then return to them for shelter. This species also exhibits territorial and agonistic behaviors to defend its shelter and access to food from conspecifics. However, it can coexist with congeners such as Echinometra viridis without competing for food or resources. (Abbott, et al., 1974; Grünbaum, et al., 1978; Weintraub, 2012)

  • Range territory size
    0 to 3 cm^2

Home Range

This species may occur in population densities of up to 240 individuals per 2.6 km^2. Individuals have been documented to travel between 0 and 3 cm^2 over a period of four days. (Abbott, et al., 1974; Grünbaum, et al., 1978)

Communication and Perception

These urchins communicate with conspecifics through tactile means, using their tube feet and spines and, when spawning, through chemical signals. It is also able to detect shadows and chemicals released by its predators. Although they have no discrete visual organs, urchins have been found to express vision related genes in their tube feet. It has also been found that their spines filter light from wide angles, allowing them to detect relatively fine visual detail (species with densely packed spines have greater acuity than those with widely spaced spines). (Blevins and Johnsen, 2004; Morishita and Barreto, 2011; Yerranilli and Johnsen, 2010)

Food Habits

This urchin is an omnivorous species, using its arboral spines to trap food and carry it to the oral surface where it uses a specialized feeding apparatus (Aristotle's lantern) to graze and consume its food. Approximately 45% of the diet consists of algae attached to the urchin's burrows and the remainder is algal drift. Some of the macrophytic algae known to be consumed by this species include Dictyota sp., Chaetomorpha sp., Sargassum sp. and Laurencia papilosa, and it is also known to consume seagrasses in the genera Thalassia and Syringodium. Gut contents of some urchins have been observed to include spines from other echinoids (resulting from territorial fights), and sessile invertebrates. (Abbott, et al., 1974; Calderon, et al., 2007; Ebert, et al., 2008; McPherson, 1969)

  • Animal Foods
  • other marine invertebrates


Predators include fishes, birds, molluscs, and humans. Triggerfish are able to break urchin tests with their strong jaws and consume the viscera, while gobies consume the urchin's tube feet and pedicellarie. Shorebirds, such as ruddy turnstones, flock over exposed reefs during low tide, pecking through urchin peristomes and eating the viscera. Conch use their radulae to drill through the urchin tests. Humans consume the gonads of this urchin. (Abbott, et al., 1974; Blevins and Johnsen, 2004; Morishita and Barreto, 2011)

This species is able to detect some invertebrate predators' odors and chemical signals, helping it to avoid predation. When attacked, an urchin waves its spines and tube feet as a defense and escape mechanism. (Morishita and Barreto, 2011)

Ecosystem Roles

This species affects the development of coral reefs through shading, physical abrasion, and incidental ingestion of sessile epifauna, thus altering the community's physical and biological structure. Because it is mainly herbivorous, it has a strong impact on algal biomass, affecting the biodiversity and functionality of its ecosystem by increasing the access to substrate for the settlement, attachment and growth of other benthic organisms. In Brazil, reduction of algal cover helped recruitment of sponges (Darwinela sp.). Most of this species' relationships are commensal. Some goby and clingfish species, as well as crustaceans, reside within its spines for protection. It is, however, also host to at least two species of ectoparasitic copepods. (Abbott, et al., 1974; Almeida, et al., 2010; Furman and Heck, Jr., 2009; Kroh, 2012; Lima, et al., 2009; McPherson, 1969; Schoppe, 1991)

Commensal/Parasitic Species
  • Red clingfish (Acyrtus rubiginosus)
  • Barber goby (Elacatinus figaro)
  • Bluebanded goby (Lythrypnus dalli)
  • Chelacheres longipalpus (Subclass Copepoda, Subphylum Crustacea)
  • Chelacheres optans (Subclass Copepoda, Subphylum Crustacea)
  • Clastotoechus vandehorsti (Family Porcellanidae, Subphylum Crustacea)

Economic Importance for Humans: Positive

Humans consume the gonads of this species. This urchin can also serve as an indicator of marine pollution by the mercury levels found in its gonads. Humans benefit from this species' role in reducing algal overgrowth and in providing protection for small cleaning fishes, which helps to maintain the health of edible reef fish. (Abbott, et al., 1974; Almeida, et al., 2010; Calderon, et al., 2007; Torres, et al., 1990; Weintraub, 2012)

  • Positive Impacts
  • food
  • research and education

Economic Importance for Humans: Negative

This species is venomous, introducing its toxin via its spines. In Brazil it is responsible for approximately half of all accidents caused by marine animals. Effects of the venom range from mild, temporary discomfort to pain and secondary infections lasting for weeks. (Sciana, et al., 2010)

  • Negative Impacts
  • injures humans

Conservation Status

As of March 2012, there is no active conservation plan for this species. This species is not endangered. (IUCN, 2012)

Other Comments

This species is called by the common names red rock urchin or rock-boring urchin, but these names have also been applied to species such as Echinometra mathaei and Echinometra oblonga. (Charpin, 2012; "Marine Life Profile: Rock-boring sea urchins", 2009)

This species can survive exposure to direct sunlight for up to three hours although water temperatures of over 38°C are lethal. (Abbott, et al., 1974)


Julio Plazas (author), San Diego Mesa College, Paul Detwiler (editor), San Diego Mesa College, Jeremy Wright (editor), University of Michigan-Ann Arbor.


Atlantic Ocean

the body of water between Africa, Europe, the southern ocean (above 60 degrees south latitude), and the western hemisphere. It is the second largest ocean in the world after the Pacific Ocean.

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living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.

World Map


living in the southern part of the New World. In other words, Central and South America.

World Map


Referring to an animal that lives on or near the bottom of a body of water. Also an aquatic biome consisting of the ocean bottom below the pelagic and coastal zones. Bottom habitats in the very deepest oceans (below 9000 m) are sometimes referred to as the abyssal zone. see also oceanic vent.


helps break down and decompose dead plants and/or animals


uses smells or other chemicals to communicate


the nearshore aquatic habitats near a coast, or shoreline.


an animal that mainly eats decomposed plants and/or animals


particles of organic material from dead and decomposing organisms. Detritus is the result of the activity of decomposers (organisms that decompose organic material).


animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature

external fertilization

fertilization takes place outside the female's body


union of egg and spermatozoan


A substance that provides both nutrients and energy to a living thing.


An animal that eats mainly plants or parts of plants.


having a body temperature that fluctuates with that of the immediate environment; having no mechanism or a poorly developed mechanism for regulating internal body temperature.

intertidal or littoral

the area of shoreline influenced mainly by the tides, between the highest and lowest reaches of the tide. An aquatic habitat.


offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

keystone species

a species whose presence or absence strongly affects populations of other species in that area such that the extirpation of the keystone species in an area will result in the ultimate extirpation of many more species in that area (Example: sea otter).


seaweed. Algae that are large and photosynthetic.


A large change in the shape or structure of an animal that happens as the animal grows. In insects, "incomplete metamorphosis" is when young animals are similar to adults and change gradually into the adult form, and "complete metamorphosis" is when there is a profound change between larval and adult forms. Butterflies have complete metamorphosis, grasshoppers have incomplete metamorphosis.


having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.


active during the night


an animal that mainly eats all kinds of things, including plants and animals


chemicals released into air or water that are detected by and responded to by other animals of the same species


the kind of polygamy in which a female pairs with several males, each of which also pairs with several different females.

radial symmetry

a form of body symmetry in which the parts of an animal are arranged concentrically around a central oral/aboral axis and more than one imaginary plane through this axis results in halves that are mirror-images of each other. Examples are cnidarians (Phylum Cnidaria, jellyfish, anemones, and corals).


structure produced by the calcium carbonate skeletons of coral polyps (Class Anthozoa). Coral reefs are found in warm, shallow oceans with low nutrient availability. They form the basis for rich communities of other invertebrates, plants, fish, and protists. The polyps live only on the reef surface. Because they depend on symbiotic photosynthetic algae, zooxanthellae, they cannot live where light does not penetrate.

saltwater or marine

mainly lives in oceans, seas, or other bodies of salt water.

seasonal breeding

breeding is confined to a particular season


remains in the same area


reproduction that includes combining the genetic contribution of two individuals, a male and a female


associates with others of its species; forms social groups.


lives alone


uses touch to communicate


defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement


the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.


an animal which has an organ capable of injecting a poisonous substance into a wound (for example, scorpions, jellyfish, and rattlesnakes).


uses sight to communicate


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Almeida, D., A. Sole-Cava, I. Calderon. 2010. The sea urchin Echinometra lucunter as a refuge for the barber goby Elacatinus figaro. Arquivos do Museu Nacional, 68/1-2: 17-23.

Blevins, E., S. Johnsen. 2004. Spatial vision in the echinoid genus Echinometra. The Journal of Experimental Biology, 207: 4249-4253.

Bolton, T., T. Florence I.M.. 2002. Physical forces experienced by echinoid eggs in the oviduct during spawning: Comparison of the geminate pair Echinometra vanbrunti and Echinometra lucunter. Journal of Experimental Marine Biology and Ecology, Volume 267, Issue 2: 123–137.

Calderon, E., C. Zilberberg, P. De Paiva. 2007. Porifera Research: Biodiversity, Innovation and Sustainability. Rio de Janeiro: Série Livros 28, Museu Nacional.

Charpin, F. 2012. "Florent's Guide to the Tropical Reefs" (On-line). Accessed August 18, 2012 at

Collin, R., M. Diaz, J. Norenburg, R. Rocha, J. Sanchez, A. Schulz, M. Schwartz, A. Valdes. 2005. Photographic identification guide to some common marine invertebrates of Bocas Del Toro, Panama. Caribbean Journal of Science, Volume 41: 638-707.

Conway, C., A. Conway, D. Igelsrud. 1984. Sea Urchin Development. Pp. 53-89 in C Harris, ed. Tested studies for laboratory teaching. Proceedings of the third workshop/conference of the Association for Biology Laboratory Education (ABLE).. Dubuque, Iowa: Kendall/Hunt Publishing Company. Accessed May 25, 2012 at

Ebert, T., M. Russell, G. Gamba, A. Bodnar. 2008. Growth, survival, and longevity estimates for the rock-boring sea urchin Echinometra lucunter (Echinodermata, Echinoidea) in Bermuda. Bulletin of Marine Science, Volume 82, Number 3: 381–403.

Furman, B., K. Heck, Jr.. 2009. Differential impacts of echinoid grazers on coral recruitment. Bulletin of Marine Science, 121–132, 2009, 85/2: 121-132.

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Echinometra lucunter (Linnaeus, 1758)
" (On-line). World Echinoidea Database. Accessed August 18, 2012 at

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Lima, E., P. Gomes, J. Sousa. 2009. Reproductive biology of Echinometra lucunter (Echinodermata: Echinoidea) in a northeast Brazilian sandstone reef. Anais da Academia Brasileira de Ciências, Volume 81(1): 51-59.

McPherson, B. 1969. Studies on the biology of the tropical sea urchins, Echinometra lucunter and Echinometra viridis. Bulletin of Marine Science, Volume 19(1): 194-213.

Morishita, V., R. Barreto. 2011. Black sea urchins evaluate predation risk using chemical signals from a predator and injured con- and heterospecific prey. Marine Ecology Progress Series, 435: 173-181.

Schoppe, S. 1991. Echinometra lucunter (Linnaeus) (Echinoidea, Echinometridae) als Wirt einer komplexen Lebensgemeinschaft im Karibischen Meer. Helgoland Marine Research, 45/3: 373-379.

Sciana, J., B. Zychar, L. Gonçalves, T. Nogueira, R. Giorgi, D. Pimenta. 2010. Pro-inflammatory effects of the aqueous extract of Echinometra lucunter sea urchin spines. Experimental Biology and Medicine, 236/3: 277-280. Accessed August 18, 2012 atçalves&sortspec=date&submit=Submit.

Torres, I., N. Ablanedo, H. Gonzalez, M. Ramirez. 1990. Evaluacion del erizo de mar Echinometra lucunter como indicador de contaminacion por metales pesados, Cuba. Aquatic Living Resources, 3: 113-120.

Weintraub, L. 2012. "Boca del Toro: Species Database" (On-line). Smithsonian Tropical Research Institute. Accessed August 18, 2012 at

Yerranilli, D., S. Johnsen. 2010. Spacial vision in the purple sea urchin Strongylocentrotus purpuratus (Echinoidea). Journal of Experimental Biology, 213: 249-255.