Génétique Systematique et des \u3ci\u3eTrichinella\u3c/i\u3e [Table ronde] = Genetics and Systematics of \u3ci\u3eTrichinella\u3c/i\u3e [Round table]

Up to the present time, the existence of two species in the genus Trichinella has been accepted by most workers. The proliferation of isolates and the definition of numerous genetic populations have caused considerable confusion in recent years for taxonomists and others concerned with these nematodes. The application of the biological species-concept to nematodes of the genus Trichinella has been difficult, but the recent investigations of Dr. E. Pozio and coworkers at the Trichinella Reference Center (Laboratory of Parasitology, Istituto Superiore di Sanita, viale Regina Elena, 299-00161 Rome, Italy) have provided new information on numerous isolates from localities worldwide. By now, discrimination of taxa of the genus Trichinella can be based on biological, genetic, and environmental characteristics, permitting the separation of four major taxa for which we recommend specific designations of: Trichinella spiralis (Owen, 1835); T. pseudospiralis Garkavi, 1972; T. nativa Britov and Boev, 1972; and T. nelsoni Britov and Boev, 1972. We recommend further that populations at the infraspecific level be named with the T-designations as published by the Rome laboratory. Because of our inadequate knowledge of isolating mechanisms, potential gene-flow among these species cannot be completely dimissed, and our recommendations are not universally supported. We believe, however, that the recommended taxonomy best reflects current knowledge. For the future, we anticipate further clarification of the genetics and systematics of Trichinella, especially if workers will continue to contribute isolates to the Trichinella Reference Center. In addition, advances in molecular genetics will permit the study of single first-stage larvae (from muscle), resulting for the first time in genetic studies of individual worms. Such advances will continue to clarify the genetics and systematics of a genus of nematodes of unusual biological interest and public health significance