白棘三列海胆

Collector urchins are dark in color, usually bluish-purple with white spines. The pedicles are also white, with a dark or black base. Individuals found at Green Island had orange-tipped spines. The spines of some specimens are wholly orange, while those of others are only orange-tipped or completely white. This color disappears when the individual dies or is taken out of the ocean, and is difficult to preserve. Collector urchins reach 10 to 15 centimetres (4 to 6 in) in size. Debris tends to “collect” on these urchins, hence their name.

喇叭毒棘海胆、花海胆

Flower urchins are relatively large sea urchins. They can reach a maximum diameter of around 15 to 20 cm (6 to 8 in). Like most echinoderms, the body of adult flower urchins is equally divided into identical segments around a central axis in multiples of five (pentaradial symmetry). The rigid “shell” (test) has five interambulacral segments separated from each other by five ambulacral segments, each of them are composed of smaller regularly interlocking plates. It is overlaid by a thin layer of skin in living individuals. The test is variegated in coloration, usually deep red and grey, though there are rare instances of green and pale purple.Each ambulacral segment is ornamented by a large purple zigzag pattern running along its length.

短刺礼服海胆、高腰海胆、蓝礼服海胆

It is a small regular sea urchin of almost spherical shape, whose diameter of the shell (called “test”) can go up to 5 cm1. The quills (“radioles”) are fine and fairly short, not exceeding 2 cm, densely arranged and ringed in black or brown with the white tip. These radioles are arranged in five times two well delimited bands (called “ambulacraires”), all the quills of each band being as “brushed” in the same direction. These bands alternate with ten other bands without spines (perradial and interradial bands), most often brightly colored deep blue (most often Duck blue, Klein blue, royal blue or verdigris, but sometimes also almost greenish black), and whose appearance is reminiscent of velvet. It is in fact a carpet of small denticulate globiferous pedicellars.

扁仙壶海胆

Maretia planulata is a sea urchin from the Maretiidae family.

The scientific name of the species was published in 1816 by Jean-Baptiste de Lamarck.

板岩铅笔海胆

Eucidaris thouarsii, the slate pencil urchin, is a species of cidaroid sea urchins that inhabits littoral regions of the East Pacific Ocean.

环刺棘海胆

The Banded sea urchin has a slightly oval test (shell), reaching a diameter of about 5 cm. Like almost all the Diadematidae (but it is in Echinothrix calamaris that it is most obvious) it has two different sets of spines, shorter and slender closed spines which are going from yellow to dark (through brown) in colour and can deliver a nasty sting, and longer and thicker spines that are often banded with light and dark colour (but sometimes all dark or all white), and reaching 10 to 15 cm in length. These radiolas can be blunt, and are hollow. The spines are grouped so as to let appear five naked zones on the central part of the test, in a star pattern (called “iridophores”): this pattern can be colored, often in blue. The anal papilla is big, more or less translucent and very obvious on the aborale face; it is generally whitish and speckled with black and white dots, circled by a ring of visual receptors that grant it a rudimentary vision.

刺冠海胆、魔鬼海胆、海须、海针、岩隐子

As a member of the class Echinoidea, the anatomy of Diadema setosum is that of a typical sea urchin. All of the animal’s internal organs are enclosed within the spherical, black test that is essentially the body of the organism. However, the body is not perfectly spherical – Diadema tests are slightly dorso-ventrally compressed. Protruding outwards from the central body are the long spines iconic of a sea urchin’s appearance. Like the other members of the family Diadematidae, the spines of D. setosum are extremely long and narrow in proportion to its body. The spines, often black but sometimes brown-banded, are hollow and contain a mild venom. D. setosum can be distinguished from other species in the genus Diadema by the presence of five white spots on the animal’s test, strategically located between the urchin’s ambulacral grooves.

长刺海胆

Diadema paucispinum is a small sea urchin with very long, moveable spines which are slender and sharply pointed. They can be up to 25 cm (10 in) long and about four times the diameter of the test. The primary spines are bluish-black in colour, often with pale bands in younger individuals. The shorter secondary ones are brittle and venomous and easily break off in the skin. There are photosensitive spots in the urchin’s epidermis and if a shadow falls on the animal, it angles its secondary spines towards the intruder. These can cause a painful sting if they come into contact with bare skin. Near the apex of the test is a clearly visible anus surrounded by an orange ring and raised on a small projection. Radiating from this are five narrow, bright blue lines.

火焰海胆

Asthenosoma varium is a sea urchin (an echinoderm, a member of the phylum that also includes star fish). Growing up to 22 cm (8.7 in) in diameter, it lives on sand and rubble sea bottoms in the Indo-Pacific, from the Red Sea to Australia and Southern Japan. Its venom tipped spines, with distinctive globular swellings below the tip, can inflict a painful sting if handled; the pain lasts as long as several hours. This capacity, perhaps coupled with its reddish-brown color, has given it the common name Fire Urchin.