The taxonomy of the Viola nuttallii complex

Abstract

1987. The taxonomy of the Viola nuttallii complex. Can. J. Bot. 65: 2562 -2580.Morphological, cytological, and phytochemical data were incorporated into numerical and statistical analyses to produce a revision of Viola subsection Nuttallianae. A basic chromosome number of x = 6 was confirmed for this polyploid~complex, which includes five species: V. vallicola, 2n = 12; V. tomentosa, 2n = 12; V. nuttallii, 2n = 24; V. praemorsa, 2n = 36 and 48; and V. bakeri, 2n = 48. Departures from recent authors include the recognition of two varieties in V. vallicola, vallicola and major (Hook.) Fabijan, based on flavonoid chemist~y and distribution. Violapraemorsa is envisaged as embracing a wide range of morphological and chemical diversity, the extremes of which are recognized as the subspecies praemorsa, flavovirens (Pollard) Fabijan, and linguaefolia. In the absence of significant morphological or distributional differences between the V. liinguaefolia and V. praemorsa subspecies major (sensu Baker and Clausen) and oregona, these three previously recognized taxa are included in subspecies linguaefolia. Based on cytological, morphological, and flavonoid data presented here, possible phylogenetic relationships are discussed. FABIJAN, D. M., PACKER, J. G . , et DENFORD, K. E. 1987. The taxonomy of the Viola nuttallii complex. Can. J. Bot. 65 : 2562-2580.Des donnCes morphologiques, cytologiques et phytochimiques ont Ct C incorporCes i des analyses numCriques et statistiques pour obtenir une revision du genre Viola sous-section Nuttallianae. Un nombre chromosomique de base de x = 6 a Ct C confirm6 pour ce complexe polyploi'de qui comprend cinq espkces : V. vallicola, 2n = 12; V. tomentosa, 2n = 12; V. nuttallii, 2n = 24; V. praemorsa, 2n = 36 et 48; et V. bakeri, 2n = 48. Les Ccarts par rapport i certains auteurs recents comprenaient L a reconnaissance de deux variCtCs du V. vallicola, vallicola et major (Hook.) Fabijan, fondCe sur la chimie et les patrons de distribution des flavonoi'des. Le Viola praemorsa est envisagC comme incluant des diversitCs morphologiques et chimiques importantes dont les extremes sont reconnus comme les sous-espkcespraemorsa, flavovirens (Pollard) Fabijan et linguaefolia. En l'absence de diffkrences morphologiques ou distributionnelles significatives entre le V. linguaefolia et le V. praemorsa sous-espkce major (sensu Baker et Clausen) et oregona, ces trois taxons, reconnus jadis comme Ctant distincts, sont inclus dans la sous-espkce linguaefolia. Les liens phylogCniques basks sur les donnCes cytologiques, morphologiques et flavonoi'des prCsentCes ici sont discutCs. [Traduit par la revue]

Establishing the phylogenetic origin, history, and age of the narrow endemic Viola guadalupensis (Violaceae)

“…Both subsections are native to the more arid parts of western North America; subsection Chrysanthae consists of summer-dormant geophytes with deeply divided leaves and (with one exception) no cleistogamous fl owers, while subsection Nuttallianae are mostly chamaephytes with entire leaves and cleistogamous fl owers ( Table 1 ). A close relationship between these subsections had been proposed previously based on rDNA (ITS) sequences ( Ballard et al, 1998 ) and the occurrence of spontaneous hybrids ( Clausen, 1964 ), and Fabijan et al (1987) suggested, based on the expression of fl avonoid compounds, that these groups might…”

“…In the original description of V. guadalupensis , Powell and Wauer (1990) suggested an affi nity with subsection Nuttallianae (W. Becker) J. Clausen, a diploid-polyploid complex (2 x to 8 x ) endemic to central and western North America ( Stebbins et al, 1963 ;Clausen, 1964 ;Fabijan et al, 1987 ) and comprising 10 Ging. Section Chamaemelanium is expanded compared to Becker ' s (1925) original treatment and includes also subsection Orbiculares (previously section Nomimium Ging.)…”

“…Here we apply a low-copy nuclear gene, GPI (glucose-6-phosphate isomerase), in conjunction with a variable chloroplast locus, the trnL-F intergenic spacer, as the best option to resolve the species networks that result from the extensive allopolyploidy North America ( Table 1 ), comprises six somewhat ambiguously defi ned and questionably monophyletic subsections. In the original description of V. guadalupensis , Powell and Wauer (1990) suggested an affi nity with subsection Nuttallianae (W. Becker) J. Clausen, a diploid-polyploid complex (2 x to 8 x ) endemic to central and western North America ( Stebbins et al, 1963 ;Clausen, 1964 ;Fabijan et al, 1987 ) and comprising 10 Ging. Section Chamaemelanium is expanded compared to Becker ' s (1925) original treatment and includes also subsection Orbiculares (previously section Nomimium Ging.)…”

Beyond Simple Reproductive Assurance: Cleistogamy Allows Adaptive Plastic Responses to Pollen Limitation

“…A second possible explanation is that C. grandiflora, an annual, has only one season to reproduce. The two species used in previous experimental studies of CH versus CL allocation under pollen limitation, V. pubescens and V. praemorsa, are both perennials (Fabijan et al 1987;Culley 2002). Annual plants are particularly likely to evolve strategies that maximize reproduction within one season because they cannot reallocate resources to future reproduction.…”

Pollen limitation and cleistogamy in subalpine Viola praemorsa

“…is a widespread species in western North America, where it can grow at elevations up to 3500 m a.s.l. (Fabijan et al 1987). Populations at high elevations experience shorter growing seasons and are likely to be visited by different pollinators; these factors might be expected to drive differences in reproductive success or breeding system (Kudo 2006).…”