ACTIVE MOVEMENTS AND OTHER ASPECTS OF THE BIOLOGY OF ASTICHOPUS AND LEPTOSYNAPTA (HOLOTHUROIDEA)

Open Access
Publisher Website
Google Scholar
Abstract
Aspects of the biology of the aspidochirotid, Astichopus multifidus and the apodid, Leptosynapta albicans, studied in Puerto Rico and California, respectively, were investigated in relation to the active movements performed by these species. Astichopus is present in greatest abundance between 10 and 40 m of depth on the northwestern coast of Puerto Rico. A smaller number of Astichopus has been collected from shallow water (1-3 m) at La Parguera on the south coast. The physical and biological characteristics of the 2 regions are contrasted with respect to the distribution of the species. Crawling, walking, bounding, rolling and an exploratory activity are some of the movements observed in Astichopus. Bounding may approach a rate of 2 m/min. Walking, bounding and rolling movements are elicited by sudden changes in the temperature of the water, of the order of 3-4[degree] C. A positive phototactic response occurs at low light intensities ([less than or equal 5 foot-candles); phototaxis increases at higher light intensities, but no definite negative response is apparent. A strong positive attraction to red, green, blue and violet light is evident at a low intensity of 10-foot-candles. Bounding movements sometimes occurred when cucumbers were suddenly subjected to diluted sea water and oxygen-deficient water. Active movements were not evoked through the association of Astichopus with members of its own species or in the presence of other animals. Coelomic fluids and alcohol extracts of the body wall of Astichopus are toxic to a variety of marine animals at concentrations of 1000-5000 ppm. Sinusoidal swimming movements were observed in adult Leptosynapta on 3 different occasions near the surface at night.

This publication has 1 reference indexed in Scilit: