Репродуктивная совместимость европейских популяций у двух видов Ulnaria (Bacillariophyta)

Clones of two morphotypes corresponding to two species of pennate araphids diatoms, Ulnaria ulna and U. acus , were isolated from samples taken in Europe. Clonal cultures entered heterothallic sexual reproduction in combinations appropriate to their mating types. Following the concept of biological species, we tested reproductive compatibility between all representatives of geographically distant populations. Isolated clones turned out to be reproductively compatible within the limits of each of the species, the progeny (generation F1) were viable and fertile, freely entering into backcrossing. No cases of interspecies hybridization were found. The absence of intraspecific reproductive isolation between distant populations in these two species suggests that the populations of both U. ulna and U. acus are conspecific.