The Breeder’s Registry© Information contained in this report is taken from submitted observations from aquarist unless noted otherwise (see comments). Information may be reproduced providing the Breeder’s Registry is cited.

Breeder ID: DIAANT-072397-BUCJEN-001

Date received: 7/23/97

Identification: Diadema antillarum (Philippi, 1845)

Geographic origin: Caribbean, Atlantic  

Taxonomy: (after I.C.Z.N.)

Kingdom Animalia

Phylum Echinodermata Subphylum Echinozoa

Class Echinoidea Subclass Euechinoidea

Superorder Diadematacea Order Diadematoida

Family Diadematidae

Genus Diadema

Species antillarum (Philippi, 1845)

Description: Long black spines (brown and black, or white and brown in young urchins), typically 3 times longer than the diameter of test. Maximum size reported varies from 15 cm (Kaplan 1982) to 30 cm (George and George 1979). Spines are hollow covered with a glandular “skin” (appears a dark maroon color) and contains a toxin. The effects of the toxin have been described as “…a slight tingling feeling and numbing of the skin…”(Buck, 1997 pers. com.), “…frequently causes severe irritation” (George and George, 1979) or “…causes beelike sting.”
(Kaplan 1982).

Nocturnal grazers which hide in crevices on reef or in aggregations in Turtle Grass beds. Feed on algae and Turtle Grass. Associations with small fish, shrimp and plankton often found among spines. Preyed upon by Balistes sp., (trigger fish).  

Duration male(yr): 0.75

Size male (mm): 50 mm (test); 190 mm (spines)

Duration female (yr): 0.75

Size female (mm): 65 mm (test); 190 mm (spines)

Broodstock notes: Both were purchased at same time.

Physical differences: Female has more small blue spots. Small iridescent blue spots developed 3 months after acquisition (~60 mm overall diameter). 5 blue evenly spaced blues lines radiating from center in between spines also developed. Very visible under actinic lighting.

Adult diet: Hair and coraline algae (grazers) continuously

Pre-spawning activity: Both moved halfway up the back wall of tank so that spines were touching, temporarily hiding the anal cone/fecal sac (commonly and incorrectly referred to as an “eye”) .

Time spawning began: evening (~1800 hours)

Area spawning occurred: not specified

Frequency of spawning: monthly

Egg description: a milky white dot with a dark center. Eggs and sperm were release at same time forming a milky cloud which later cleared. Released from released from blue ring and spots around anus. Lasted ~ 20 minutes.

Approximate quantity: unknown

Size: a “speck of sand”

Egg changes / development: Eggs rose immediately towards surface remaining within 5 cm of surface. 8 days later round black “dots” appeared on the sand.

Transfer / removal method: not removed, but filter turned off.

Spawning tank size (liter): 280, 23.6 cm long x 56 cm deep x 46 cm tall

Sides of tank covered? Yes, back is mirrored

Lighting & photo period: 1 40 watt Tri-Lux® fluorescent and 1 40 watt actinic fluorescent. 14 hours ~ 6 cm from surface. Changed every 18 months.

Filtration: Protein skimmer (Creative Plastics ®) and 2 power heads

Additives and dosages: Synthetic seawater, monthly changes, Kalkwasser, Combisan® monthly, occasionally RO

Water temperature (F): 75

Specific gravity: 1.022

pH: 8.0 (Aquarium Systems test kit)

Nitrate: 5 ppm (Aquarium Systems test kit)

Fry development / changes: none reported

Original description: Philippi, 1845. No other information available

Word origin: The genus Diadema is Greek for a crown or turban. (The synonym genus Cidarisis also Greek for a turban; Centrechinus is from the Greek root centr meaning center a point; and echinus which is the Greek word for a sea urchin (also a hedgehog). The species antillarium is from the New Latin word antillar meaning “of the Antilles” in reference to the Greater and Lesser Antilles in the West Indies which divides the Caribbean Sea and Atlantic Ocean. The name can be translated literally to “Crown of the Antilles”.

Synonomy: Centrechinus antillarum, Cidaris antillarum

Vernacular name: Long spined sea-urchin

Suggested reading:

George, John D., & George, Jennifer J., Marine life, 1979, Lionel Levethal Limited, 2-6
Hampstead High Street, London NW3 1QO, UK., A Wiley-Interscience Publication, ISBN
0-471-05675-8

Kaplan, Eugene H., A Field Guide to Coral Reefs of the Caribbean an Florida, 1982, Houghton
Mifflin Company, 2 Park Street, Boston, MA 02108, ISBN 0-395-31661-8

Stearns, Louis W., Sea Urchin Development: Cellular and Molecular Aspects, 1978, Dowden,
Hutchinson & Ross, Inc., 523 Sarah Street, Stroudsburg, PA 18360 USA. ISBN 0-87933-026-0

About this report: Information contained in this report is taken from submitted observations. Taxonomy, Synonomy, Original description , Word origin and Suggested reading are provided by member(s) of The Breeder’s Registry staff. Information is presented under the belief that it is accurate. If you have information in addition to, or contrary to that presented you are encouraged to contact the Breeder’s Registry. Permission is granted for “one-time” personal use. Reproduction as distributed or accessible media is prohibited without prior written permission. All rights reserved. 1997