The Identity and Biology of Unio Mancus Lamarck, 1819 (= U. Elongatulus) (Bivalvia Unionidae) in the Iberian Peninsula

7 páginas, 2 figuras, 2 tables..Genetic variability, shell morphology, anatomy, reproductive season, glochidium morphology and host fish of several Iberian populations of Unio mancus Lamarck, 1819 ( = U. elongatulus C. Pfeiffer, 1825) were examined. The genetics of three allopatric populations were studied, including two ‘races’ previously described for this species on the Iberian Peninsula. All shared the same haplotype of the COI mitochondrial gene. It is proposed that all known Iberian Mediterranean populations of the genus Unio correspond to Unio mancus. All mature specimens studied were dioecious. Glochidial release occurred between March and August. The barbel Barbus graellsii was the natural host of the U. mancus glochidia in the studied area. In artificial infestations performed in aquaria, seven fish species, all native, carried the glochidia throughout their complete metamorphosis. This process occurred in 141 degree/days. Newly released juveniles were spherical and had a thin marginal rim of new shell.We wish to thank to the Departamento de Medio Ambiente de la Diputación General de Aragón (DGA) for their support with the project Conservación de especies amenazadas de moluscos acuáticos de AragónPeer reviewe