The taxonomic status and relationships of bracken ferns (Pteridium: Dennstaedtiaceae) from sub-Saharan Africa

Two morphotypes of bracken fern in the genus Pteridium Gled. ex Scop. occur in sub-Saharan Africa. The more common and widespread of these is assigned in contemporary systematic treatments to the European subspecies, P. aquilinum (L.) Kuhn ssp. aquilinum . We show that this African form is separable morphometrically and genomically from the European subspecies, and reinstate its earlier name P. aquilinum ssp. capense (Thunb.) C.Chr. The second African bracken, with a more localized tropical distribution mainly in the drainage basins of the Congo and Zambezi River systems, is confirmed as P. aquilinum ssp. centrali-africanum Hieron. ex R.E. Fr. We reject suggestions that this taxon be treated as a full species. Phenetic cluster analysis based on use of Arbitrarily Primed Polymerase Chain Reaction (A-P PCR) and Inter Simple Sequence Repeat (ISSR) fingerprinting of the nuclear genome provides evidence that the two African brackens are more closely related to each other than to other taxa, and sister to a grouping of the European sspp. aquilinum and pinetorum . The two African subspecies share solely with ssp. aquilinum a distinctive chloroplast haplotype carrying a 5-base direct repeat in the rps 4 –trn S region, confirming the close phyletic relationship between sspp. aquilinum , capense and centrali-africanum .  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 311–321.     

Morphological and pollen differentiation in Solanum cardiophyllum ssp. cardiophyllum and S. cardiophyllum ssp. ehrenbergii

A multivariate analysis to differentiate morphologically the populations of wild potatoes Solanum cardiophyllum ssp. cardiophyllum and S. cardiophyllum ssp. ehrenbergii was carried out. An analysis of the morphology and the viability of pollen of these potato populations was also made. The results of the morphometric analysis indicate that both subspecies are phenetically different. The pollen grain shape and size in ssp. cardiophyllum are different in northern and southern populations. Pollen diameter is significantly different between subspecies. Based on these results we propose that these taxa should be considered as two separate species.  © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 140 , 415–426.     

A phenetic analysis and revision of Guineo-Congolean rain forest taxa of Chlorophytum (Anthericaceae)

The taxonomy of rain forest species of the genus Chlorophytum in central and west Africa has to date been difficult to resolve. Plants collected in the Guineo-Congolean plant geographical region deposited in several herbaria formed the basis for a morphometric analysis using Principal Component Analyses and including 16 characters. In total, 166 individuals were included from 461 herbarium collections, from which 57 seeds were scanned to investigate the surface structures. Eight species are recognized, including one with three subspecies and another with three varieties. Four new combinations are proposed ( Chlorophytum comosum (Thunb.) Jacques var. bipindense (Engl. & K. Krause) A.D. Poulsen & Nordal, C. comosum (Thunb.) Jacques var. sparsiflorum (Baker) A.D. Poulsen & Nordal, C. lancifolium Baker ssp. cordatum (Engl.) A.D. Poulsen & Nordal, and C. lancifolium Baker ssp. togoense (Engl.) A.D. Poulsen & Nordal), ten new synonyms are introduced and three lectotypes are designated.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 1–20.     

Iris stenophylla Hausskn. & Siehe ex Baker from Turkey and its cytology

A morphological study, both in the field and from herbarium material, showed that there are no convincing characteristics separating the Turkish endemics Iris stenophylla ssp. stenophylla and ssp. allisonii . A cytological survey revealed chromosome numbers of 2 n  = 24, 26 and 26 + 1B. No variation in either chromosome number or karyotype was found in ssp. allisonii , which always had 2 n  = 26, although the chromosome number and karyotypes of ssp. stenophylla were variable. Since neither morphological nor cytological differences were sufficient to separate the two subspecies, I. stenophylla ssp. allisonii is therefore reduced to a synonym of I. stenophylla .  © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 140 , 115−127.     

New distributional and molecular information call into question the systematic position of the West Asian Viola sintenisii (Violaceae)

The west Asian Viola sintenisii W.Becker, described from temperate woodlands of northern Iran and south-western Turkmenistan on the Caspian coast, was long considered a vicariant geographical subspecies of the mainly south European V. alba Besser. The new findings of V. sintenisii in four geographically separated stations in north-eastern Azerbaijan significantly expands its range of distribution. These occurrences are within the range of V. alba ssp. alba . Here the two taxa frequently co-occur but remain distinct and V. sintenisii is therefore justified at species level. It is likely that the two species are also sympatric in the Hyrcanian region, a range previously attributed uniquely to the latter. Viola sintenisii seems to be fairly common in the eastern parts of the Great Caucasus, but there are reasons to suggest that it has there been misinterpreted as V. suavis . The chromosome number of V. sintenisii , 2 n  = 20, is reported here for the first time.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 147 , 91–98.     

Synopsis of Turkish Acantholimon Boiss. (Plumbaginaceae)

A synopsis of Acantholimon in Turkey is given on the basis of a revisional study conducted in Turkey by the authors. An account of 52 species, ten subspecies, and 17 varieties is given, including keys to the species, subspecies, and varieties, and a general indication of their distribution, as well as their conservation status in Turkey. Seven new taxa, namely A .  ekimii sp. nov. , A. capitatum ssp. sivasicum ssp. nov. , A. calvertii var. glabrum var. nov. , A. huetii var. breviscapum var. nov. , A. acerosum ssp. longibracteolorum ssp. nov. , A. lycaonicum ssp. cappadocicum ssp. nov. , and A. halophilum var. coloratum var. nov. , are described, together with a few new combinations. A. wiedemannii , A. iconicum , and A. lycaonicum , described from Turkey in the past, but placed under other species as synonyms in the Flora of Turkey , are recognized once again as good species. A. multiflorum and A. parviflorum are given a species status. In Turkey, the presence of A. latifolium , A. araxanum , A. lepturoides , A. hohenackerii , A. senganense , A. fominii , A. petraeum , and A. tragacanthinum is also confirmed.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 154 , 397–419.     

Revision of the Clinopodium abyssinicum group (Labiatae)

A tropical African group of species commonly included in the genus Satureja is revised and moved to the genus Clinopodium . Satureja abyssinica (Benth.) Briq. ssp. abyssinica and ssp. condensata (Hedberg) Seybold, S. paradoxa (Vatke) Engl. ex Seybold, S. robusta (Hook.f) Brenan and S. vernayana Brenan should be known under the following names: Clinopodium abyssinicum (Hochst. ex Benth.) Kuntze var. abyssinicum and C. abyssinicum var. condensatum (Hedberg) Ryding, C. paradoxum (Vatke) Ryding, C. robustum (Hook.f) Ryding and C. vernayanum (Brenan) Ryding, respectively. Satureja cacondensis (G. Taylor) Brenan, S. masukuensis (Baker) Eyles and S. myriantha (Baker) Brenan, including its varieties, are amalgamated and should be known by the name Clinopodium myrianthum (Baker) Ryding.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 150 , 391–408.     

Clarification of the systematic position of Hippophae goniocarpa (Elaeagnaceae)

New information on (1) Hippophae goniocarpa Y.S. Lian et al . ex Swenson et Bartish and (2) H. goniocarpa ssp. litangensis (Lian et X.L. Chen ex Swenson et Bartish) Lian et K. Sun from China is provided and illustrated. Based on morphological characters and distribution, H. litangensis Y.S. Lian et X.L. Chen ex Swenson et Bartish is re-described as a subspecies. H. goniocarpa (including ssp. litangensis ) is a distinct species and should be placed in Section Gyantsensis of Hippophae , although it has been suggested that sspp. litangensis and goniocarpa are the result of hybridization between H. rhamnoides ssp. sinensis and H. neurocarpa ssp. neurocarpa , and H. rhamnoides ssp. yunnanensis and H. neurocarpa ssp. stellatopilosa , respectively. The type subspecies of H. goniocarpa is distributed in Songpan and Hongyuan Counties of Sichuan Province and Qilian County of Qinghai Province, at 3500–3750 m, whereas ssp. litangensis is found only in Jiawa, Litang County, Sichuan Province at c . 3700 m. A key including the four taxa of sect. Gyantsensis is provided.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 142 , 425−430.     

Taxonomic status and relationships of bracken ferns (Pteridium: Dennstaedtiaceae) of Laurasian affinity in Central and North America

Detailed quantitative comparisons confirm and extend the discrimination of four major morphotypes amongst brackens of Laurasian affinity in Central and North America. These are recognized here at subspecies level as: Pteridium aquilinum sspp. feei , pubescens , latiusculum , and pseudocaudatum . Measurements of spore size indicate that sporophytes of P. aquilinum ssp. feei are diploid (2 n  = 104), as are sspp. pubescens , latiusculum , and pseudocaudatum . Phenetic cluster analysis based on DNA fingerprinting by arbitrarily primed polymerase chain reaction groups these four subspecies as genomically more similar to each other than to any taxa from other geographical regions. The chloroplast haplotype of ssp. feei is the same as that of sspp. latiusculum , pseudocaudatum , and pubescens with respect to the absence of both of the short direct repeats in the rps 4– trn S region (haplotype A), whereas the European ssp. aquilinum (haplotype B) has one of these repeats, and the Southern Hemisphere brackens P. arachnoideum and P. esculentum (haplotype C) have the other.  © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 157 , 1–17.     

A new species of Aethionema (Brassicaceae) from the Bulgarian flora

Aethionema rhodopaeum D. Pavlova is described as a new species from the eastern Rhodope Mountains. The plant was found growing only on serpentines, in two localities, at an altitude of approximately 400 m. The localities are typical open habitats with sparsely colonized debris. The plant communities, composed mainly of xerophytes with a mosaic distribution, contain a large number of rare and endemic species for the Bulgarian flora. The new species belongs to the Aethionema saxatile group and is quite close to the species A. saxatile (L.) R. Br., in particular to ssp. creticum and ssp. graecum . The following diagnostic features are given for the new species: inner filament length always greater than half the petal length, lack of teeth of the filaments, longer [2–3(3.5) mm] style than that of A. saxatile subspecies, and dark purple petals. All leaves are broadly elliptical to suborbicular, obtuse, and fleshy. The chromosome number of the new species is 2 n  = 24. The differences between the new species and related taxa are also discussed.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 155 , 533–540.     

A morphometric study of three closely related taxa in the European Isoetes velata complex

Isoetes velata A. Braun is an amphibious plant with Mediterranean and Ibero-Atlantic distribution, showing marked morphological variability. Within the same geographical area, closely related restricted-range taxa are also present, including I. velata ssp. asturicense (restricted to mountainous areas of the north-west Iberian Peninsula) and I. boryana (restricted to the southern French Atlantic coast). These related taxa have unclear taxonomy and are both threatened. We performed a morphometric study of specimens of the three taxa. Our results suggest that I. velata ssp. asturicense is better considered as a distinct species, I. asturicense Laínz (Laínz), distinguishable from the other two taxa by mean megaspore length ( N  ≥ 30) < 360 µm. In contrast, our results do not support consideration of I. boryana as a separate species, and we here propose that this taxon be considered as a variety, I. velata A. Braun var. boryana M.I. Romero & C. Real stat. nov.   © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 459–464.     

The effects of loss of sex in clonal populations of an endangered perennial Coptis teeta (Ranunculaceae)

The reproductive biology of two subspecies of Coptis teeta was studied. The species is an endangered, herbaceous perennial, endemic to the Mishmi Hills in Eastern Himalaya . We investigated reproductive strategies of the subspecies, their breeding systems and reproductive output. They had contrasting reproductive strategies; ssp. teeta reproduces sexually and produces fewer ramets, while ssp. lohitensis propagates mostly vegetatively through a higher number of ramets . There is a resource adjustment between vegetative and sexual functions with a greater allocation to the former, particularly in ssp. lohitensis. Manual crosses showed that the species is self- and cross-compatible, but is essentially an autogamous selfer. Seed set in the species is generally low, with higher output in ssp. teeta and lower in ssp. lohitensis. The low fecundity is ascribed to a number of pre- and postfertilization events, including unsuitability of floral features for attracting pollinators, high pollen sterility and high rates of fruit and seed abortion. Sexual reproduction does not contribute significantly towards population increase in this species. This could be an important factor contributing to its rarity.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 143 , 47−54.     

Two new taxa and a new combination for Stipa (Gramineae: Stipeae) in Tunisia

Two new taxa in Stipa L. Sect. Leiostipa Dumort., S. alba and S. letournexii ssp. ignea , are described from southern Tunisia (northern Africa). In addition, the S. letournexii complex is reviewed and a new combination, S. letournexii ssp. tunetana (H.Scholz) F.M. Vázquez, is presented.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 153 , 439–444.     

A revision of the Nasa ranunculifolia group (Nasa ser. Grandiflorae pro parte,Loasaceae)

The monophyletic Nasa ranunculifolia group (Nasa ser. Grandiflorae pro parte) is revised on the basis of extensive field studies and a revision of copious herbarium material. All species of this group are from the high Andes of Peru and Ecuador (mostly 3000–4300 m). The overall degree of morphological divergence is much lower than in other groups of Nasa and many of the various local ‘races’ are best recognized as ecogeographically isolated subspecies. Thus, six species and 13 subspecies are recognized on the basis of differences in leaf and floral morphology, growth habit, life history and distribution. Nasa ranunculifolia, N. macrantha, N. cymbopetala and N. macrorrhiza are united as subspecies under N. ranunculifolia. An additional five subspecies of N. ranunculifolia are newly described (ssp. pamparomasii, ssp. guzmangoensis, ssp. bolivarensis, ssp. patazensis and ssp. huanucoensis). Nasa rugosa is subdivided into four subspecies, three of them new (ssp. llaqtacochaensis, ssp. gracilipes and ssp. pygmaea). Nasa tulipadiaboli sp. nov. and N. basilica sp. nov. are described as new species. Eight taxa (seven subspecies and one species) are endemic to the Amotape–Huancabamba Zone, and seven of them (six subspecies and one species) are new to science. Only a single species ranges into the Amotape–Huancabamba Zone from the south, underscoring the high levels of endemism (and taxonomic novelty) in this area. Illustrations, distribution maps, a key and diagnoses are given for all taxa recognized. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, 167 , 47–93.     

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

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.