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The demand and high market price for sea cucumber has led to the collapse of wild stocks for many traditional species in Asia and the Indo-Pacific. New species have therefore been introduced to the...

Aim: Accidental inoculation of humans with veterinary vaccines can lead to early and late complications. The aim of our study is to describe these complications and their risk factors.Methods: Pros...

Penilpidia desbarresi sp. nov. was collected in the Desbarres Canyon at a depth of 525 m, off the southeastern coast of insular Newfoundland, eastern Canada. The new species differs from the type species Penilpidia ludwigi (von Marenzeller, 1983) in having larger middle spines on arched rod-type ossicles on the dorsum and by having the lobe around the posterior body end formed by six pairs of very small tube feet. Penilpidia desbarresi sp. nov was photographed in situ and sampled on a single occasion in July 2007. This gonochoric species (1� 2 cm long) was found on a muddy substrate and individuals were aggregated, reaching a density of 50 ind. m � 2 . Preliminary evidence points to brooding, which would be a first for the family Elpidiidae. Penilpidia ludwigi, not recorded for more than 100 years after its first description, is re-described.

The original and only description of the cucumariid holothurian species Trachythyone nina (Deichmann, 1930) is based on material collected near George's Bank, by the US Fish Commission Steamer Albatross 125 years ago. No additional material of this species has been formally reported ever since. We hereby record T. nina for the first time in Canadian waters, from several sites along the continental slope of Newfoundland and Labrador (43–55° N) at depths of 1088–1308 m and from the Arctic (60° N) at 590 m, as well as from two sites near the type locality at 132–155 m along the coast of New England. A more detailed and accurate description of the species is provided, along with notes on its ecology and distribution. This tiny (≤15 mm long) gonochoric sea cucumber is usually associated with hard substrata, including deep-sea corals.

Summary Holothurians are among the most commercially valuable echinoderms for which successful spawning induction under laboratory conditions is still difficult to obtain on a reliable basis. The present study demonstrates that the transfer of perivisceral coelomic fluid (PCF) can be used as a reliable tool to induce spawning in mature individuals. PCF collected from holothurians that had been in the typical spawning posture, without shedding gametes, for ca. 20 min triggered spawning in 71 to 100% of conspecifics. The individuals responded to the injection of a 2–3 ml aliquot by displaying the spawning posture within 30–62 min and by massive gamete broadcast 57–83 min later. The results varied according to the time of PCF collection with respect to the spawning activity of the donor and the amount of PCF injected. The inductive substance was found not to be sex—specific since positive responses were observed in individuals of the same or opposite sex as the donor. The PCF of a spawning donor was also act...

The tropical holothurians, Holothuria leucospilota, Bohadschia argus and B. marmorata responded to tactile stimulation by expelling Cuvierian tubules in proportion to the intensity of the stimulation. They were able to target the stimulated area with variable success depending on the location of the stimulus. Held surveys showed that 2.3–6.1% of H. leucospilota presented signs of having recently used their Cuvierian tubules and laboratory experiments revealed that they released tubules in response to several natural predators. The tubules did not adhere nor cause any distress to fish, but proved effective in discouraging attacks. Crabs, molluscs and echino‐derms were entangled and also efficiently repelled. H. leucospilota without tubules were wounded and even killed by predators that were usually discouraged by tubule discharge. Conversely, after having induced the release of tubules once, 96% of the predators placed in the presence of H. leucospilota three days later remained at a distance. Released tub...

A new species of pea crab, Pinnotheres halingi sp. nov. (Pinnotheridae), found encysted in the right respiratory tree of the sea cucumber, Holothuria scabra (Holothuridea), from Solomon Islands, is described. The reproduction, infestation and pairing behaviour of the crabs were investigated through field observations and experiments. Infestation frequency in 8 monthly samplings of 25–30 holothurians was 98.6±2.6% in Kogu Halingi bay and 0% in two nearby sites. Of 403 pea crabs, 91.4% were found in pairs of opposite sex, 7.9% were single females and

Summary Cross-fertilization experiments were conducted using two species of asteroids, one echinoid, one holothuroid and two species of mollusks to dertermine whether gametes from members of different classes, and even different phyla, are naturally able to fertilize one another. All but one of the crosses were successful, showing variable success, 58–99% lower than for intraspecific fertilization. Although most were not viable and showed anarchic cleavage, some resulting embryos could be reared to the blastula stage. Furthermore, these experiments led to the first case of intergeneric hybridization among asteroids, resulting in viable post-metamorphic sea stars. The hybrids of Leptasterias polaris (spermatozoa) and Asterias vulgaris (oocytes) showed a developmental kinetic, a survival rate and an external phenotype similar to those observed after normal intraspecific fertilization in A. vulgaris. In natural conditions a temporal barrier appears to be the key in preventing such hybridization, as these two...