Venomous urchins

Venom from the globiferous pedicellariae of sea urchins is lethal to mice, rabbits, crabs, lobsters, and worms 70). Seasonal changes in toxicity of such toxins 71) have been observed. The LD q estimate (mice) for toxic fractions from the urchin Tripneustes gratilla ranged from 0.05-0.5 mg/kg 70). 

Species with pedicellaria include those reputed to be the most venomous of all sea urchins, the flower urchins Toxopneustes species). Pedicellaria are small, delicate, tripled-jawed seizing organs that are supported by basal calcareous plate or embedded in the body stiff integument. 

There are two types of venom delivery systems used by Sea Urchin. Venom within the spines is released after the spine penetrates the skin. Penetration of the skin by the spines also results in the release of violet-colored fluid that stains the wound and is a good indicator of penetrating injury. In addition to the spines, there are also seizing organs on the surface of the sea urchin scatted among the spines called Pedicellariea. The Pedicellariea will continue to deliver venom into the skin, even if they are broken off of the body of the sea urchin. 

I toxins. Among the echinodermata, the stalked grasping organ (pedicellaria) of isolated species of sea urchins and st sh may also serve as a poison weapon. The sea urchin Toxopneustes pileolus is much feared in East Asian waters. Other species of sea urchins also possess poisonous spines (e.g., Diadema setosum). The chemical composition of the venoms is mostly unknown. The cuvierian organs extruded from the cloaca of sea cucumbers when disturbed from sticky fibers in water may also secrete a venom, e.g., the holothurins see also echinoderm saponins. 

Burnett JW, Calton GJ, Burnett HW (1986a) Jellyfish envenom-ation syndromes. J Am Dermatol 14 100-106 Burnett JW, Calton GJ, Morgan RJ (1986b) Venomous sea urchins. Cutis 38 151... 

Mansson T, Randle HW, Maudojana RM, Calton CJ, Burnett JW (1985) Recurrent cutaneous jellyfish eruptions without en-venomation. Acta Derm Venereol 65 72-75 Maretec Z, Russel FE (1963) Stings by the sea Anemonia sulcata in the Adriatic sea. J Trop Med Hyg 32 891-894 Meneghini CL (1972) Cases of sea urchin granuloma with positive intradermal test to spine extracts. Contact Dermatitis Newsletter 12 316... 

Nakagawa, H., Tu, A. T, and Kimura, A., 1991, Purification and characterization of Contractin A from the pedicellarial venom of sea urchin, Toxopneustes pileolus. Arch. Biochem. Biophys. 284 279-284. 

Nakagawa, H., Tomihara, Y, Araki, Y, and Hayashi, H., 1994, Preliminary studies on venom proteins in the pedicellariae of the toxopneustid sea urchins, Toxopneustes pileolus and Tripneustes gratilla. J. Natural Toxins. 3 25-34. 

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