Notes on Carex pallidula
(C. pallens (Fristedt) Harmaja)

C. pallidula Harmaja (C. pallens (Fristedt) Harmaja; Cyperaceae) was reported by me as a valid but neglected species from northern Europe: Finland, Sweden and Russian Karelia (Harmaja, H. 1986: Carex pallens, an overlooked Fennoscandian species. – Ann. Bot. Fennici 23: 147-151.). Previously, this sedge was considered as a variety of the closely related C. digitata L. In addition, the new hybrid C. digitata × pallidula was reported from Finland. Later (Harmaja, H. 1990: On the taxonomy and chorology of Carex pallens. – Ann. Bot. Fennici 27: 79-83.), additional information was given and the species was reported also from Central and SE Europe (Bohemia, Slovakia, Slovenia, Montenegro). News concerning C. pallidula are presented on the present webpage.

The late Professor Josef Holub screened specimens filed as C. digitata L. in the herbaria of Czechoslovakia. He detected a considerable amount of C. pallidula among that material (Holub, J. 1991: A significant extension of the knowledge of the distribution area of Carex pallens (Fristedt) Harmaja in Central Europe. – Cyperaceae Newsletter 8: 9-10.). The species was not uncommon in the hill country of western Bohemia, possessing a conspicuously sharp eastern limit of distribution, while Moravia almost lacked occurrences. In Slovakia, C. pallidula is known in some localities; these are rich in rare and interesting species.

In 1991, C. pallidula was found as new to Republic of Karelia by a Finnish-Russian lichenological expedition. The locality lies in the famous Vodlozero (Vodlajärvi) National Park, in a mixed forest with Larix sibirica at the NW edge of the spontaneous distribution of this larch species. The specimen of C. pallidula is deposited in the Botanical museum (H) of the Finnish Museum of Natural History. This concerns a considerable eastward extension of the known area of the species, representing the easternmost post.

The species was reported as new to Poland by Zbigniew Szeląg (Szeląg, Z. 2001: Carex pallens (Cyperaceae), a species new to Poland. – Polish Botanical Journal 46: 75-77.). The species was found in four localities growing among herb-rich thermophilous flora in calcareous hill country.

Torbjörn Tyler from Sweden performed a most interesting study on the allozymes of Carex sect. Digitatae (Fr.) Christ. (Tyler, T. 2003: Allozyme variation in Carex sect. Digitatae – Evidence of introgression, genetic distinctiveness and evolution of taxa. – Plant. Syst. Evol.237: 219-231.). He could confirm with molecular methods three facts which I had previously detected and published using traditional methods combined with extensive field experience: (i) C. pallidula is distinct at the specific level, (ii) C. digitata and C. pallidula are capable of hybridizing with each other, and (iii) C. pediformis C.A.Meyer ssp. rhizodes (Blytt) H.Lindb. is not so closely related to C. digitata and C. pallidula as generally believed.

Because of an older homonym, C. pallens (Fristedt) Harmaja needed a new name: Harmaja, H. 2005: Carex pallidula, nom. nov. – Ann. Bot. Fennici 42: 221-222.