New and little known nematodes from the North Sea

Two new species of free-living marine nematodes from a sublittoral region in the North Sea off the Belgian coast are described: Richtersia deconincki sp.n. and Pomponema coomansi sp.n. Gonionchus villosus Cobb, 1920 is rediscovered and redescribed. Calomicrolaimus monstrosus (Gerlach, 1953) comb.n. is discussed and Microlaimus conspicuous Lorenzen, 1973 is synonymized with it. Females and juveniles of M. annelisae Jensen, 1976 were also found and are discussed; since the holotype of this species is lost, a neotype has been designated

Deux espèces nouvelles d'Ironidae marins; observations sur les spermatozoïdes flagellés des Nématodes

Description of a new species of Syringolaimus, S. renaudae n. sp., from the Cape Basin, south western Atlantic deep-sea ooze from 3 694 to 4 180 m depth. S. renaudae n. sp. is characterized by its rather large size, its cephalic collar, three bifid and asymétrie teeth, extension of pharyngeal bulb and spicule morphology. Noteworthy are the very peculiar spindleshaped and flagelliform spermatozoa, that are similar to those found in S. loofi n. sp. described from the coast of the Netherlands

Nématodes marins de Guadeloupe: V. <i>Lauratonema spiculifer</i> Gerlach,1959; description du système reproducteur des Lauratonematidae

Lauratonema spiculifer Gerlach, 1959, is redescribed. Females are devoid of vulva and possess a characteristic intra-uterine sphincter. The two genera of the Lauratonematidae are discussedwith peculiar references to the female genital system structures of L. spiculifer and Lauratonemoides originalis (Gerlach, 1956)

Nématodes abyssaux (campagne Walda du N/O <i>Jean Charcot</i>): VI. Le genre <i>Acantholaimus</i>: espèces nouvelles et étude de l'appareil reproducteur à spermatozoïdes géants

Three new species of the genus Acantholaimus are described from deep-sea South- East Atlantic oozes (Walvis ridge, depth from 2 063 to 4 308 m) : A. microdontus n. sp., A. macramphis n. sp., and A. longistriatus n. sp. Within the genus, the reproductive apparatus displays a noticeable uniformity coupled with a very unusual male reproductive system producing a small number of giant spermatozoa, of which only two were found in each inseminated female. Four additional species studied from the same sites display the same reproductive pattern : A. quintus, A. septimus, A. maks and A. iubilus ( G E R L A C H et al., 1979). The same phenomenon has also been found in a littoral species (at most four spermatozoa in the inseminated female)

Larval development and biology of <i>Canuella perplexa</i> T. and A. Scott, 1893 (Copepoda, Harpacticoida)

Canuella perplexa is often a dominant species in meiobenthic communities of the northern hemisphere. The biology (propulsion, feeding behaviour, precopulatory behaviour, and hatching) and larval development of this species were examined on animals reared in the laboratory. Characters of the nauplius which were considered by Lang (1948) to be diagnostic of the Polyarthra will have to be reexamined in the light of the results on C. perplexa. The post-embryonic stages of the Canuellidae are morphologically different from the larval stages of the also primitive Longipediidae