The Deschampsia cespitosa complex (Poaceae: Aveneae) with special reference to Russia

Abstract

The Deschampsia cespitosa complex in Russia is revised. Related taxa common to Russia and adjacent regions (i.e. northern Europe, Arctic America and Japan) are also considered. Deschampsia cespitosa s.l. is characterized by open to less commonly rather contracted panicles, spikelets (1) 2 (3)‐flowered, 4‐toothed lemmas with the lateral teeth larger, and awns straight or bent, inserted from the base to the top of the lemmas. Due to extensive overlapping in diagnostic characters, it is not possible to accept the specific status for D. borealis (Traut.) Roshev., D. brevifolia R.Br., D. macrothyrsa Tatew. et Ohwi and D. obensis Roshev; instead, they are treated as subspecies of D. cespitosa (L.) Beauv. Morphological differences are insufficient for a clear differentiation among subspecies, and geographical distributions also need to be considered. A total of 14 subspecies is accepted. Observations on ecology, problems of specific and subspecific delimitation, a distribution map, and considerations of evolution of the complex are provided. One new combination is made, Deschampsia cespitosa ssp. sukatschewii (Popl.) Chiapella & Prob. © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society, 2003, 142, 213–228.

New taxa of Deschampsia P. Beauv. (Poaceae) from Russia

“…or s.s), be cause the existence of intermediate forms (probably hyb rids) among putative species makes differentiation very dif ficult. In previous publications (Tzvelev 1976, Chiapella & Probatova 2003 we treated many taxa present in Russia as subspecies of one, but very polymorphous D. cespitosa. However this approach of using subspecies proved to be in con venient when confronted with the extreme variability found during the revision of the abundant herbarium mate rial of the genus from the Russian Far East (RFE) and Si be ria preserved in the Herbarium of the Institute of Biolo gy & Soil Science in Vladivostok (VLA).…”

Taxonomic studies on Senecio aquaticus (Asteraceae). A recommendation for the taxonomic status of Aquaticus and Barbareifolius

“…Dobzhansky, 1970; Mayr, 2000; Meier & Willmann, 2000). A subspecific status may be chosen for both groups if they show discrete, but overlapping distributions in morphometric space and can be considered as regional facies of S. aquaticus with restricted geographical distributions (Du Rietz, 1930; Mayr, 1970; Chiapella & Probatova, 2003). In the absence of such differences in the geographical distributions of Aquaticus and Barbareifolius, the taxonomic status of variety will be advised.…”

The Evolutionary History of New Zealand Deschampsia Is Marked by Long-Distance Dispersal, Endemism, and Hybridization

“…Several taxa of Europe and Asia, including D. koelerioides, have sometimes been classified as a subspecies of D. cespitosa [88]. The taxonomical status of several endemic taxa in Europe and Asia is often debated [39,40,89].…”

“…Extant populations of the cosmopolitan D. cespitosa in the Southern Hemisphere are considered ancient migrants [37,38] and thus regarded as native. To our knowledge there is no investigation involving a global sample of D. cespitosa or a phylogeny of the genus involving a worldwide sample, although there are several investigations covering larger regions using morphological [39,40] or molecular approaches [41,42].…”