The taxonomy of theCarex roseagroup (sectionPhaestoglochin) in Canada

摘要

TheCarex roseagroup, part of sectionPhaestoglochin, consists of four species, three of which,C.appalachicaWebber amp; Ball,C.roseaSchkuhrexWilld., andC.radiata(Wahlenberg) Small, occur in Canada. It is shown that some characters used to separate the species, i.e., perigynium length, colouration of the orifice of the beak, number of perigynia per spike, and length of the lowest infructescence bract, are unreliable. Other characters, such as the widths of the broadest leaves and fertile culms, width and degree of coiling of the stigmas, shape of the perigynium base, and position of the achene within the perigynium, were found to afford a reliable separation of the species. Analysis of mixed populations ofC.rosea,C.radiata, andC.appalachicasuggests that hybridization does not occur. The chromosome numbers of the three Canadian species were found to be as follows:C.rosea,nensp;=ensp;26;C.radiata,nensp;=ensp;29; andC.appalachica,nensp;=ensp;26. Distribution maps of the three species in North America are also given.