Fossil palm flowers in Dominican and Baltic amber

Five palm flowers in Dominican amber and one in Baltic amber are described or characterized. Palaeoraphe dominicana gen. et sp. nov. in the subtribe Livistoninae, is described from one perfect flower in Dominican amber. Roystonea palaea sp. nov. is described from one staminate and one pistillate flower in Dominican amber. Three other palm flowers, two perfect flowers from Dominican amber and one staminate flower from Baltic amber, are briefly characterized and figured.  © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 139 , 361–367.     

Chromosomal criteria and their phylogenetic implications in the genus Onobrychis Mill. sect. Lophobrychis (Leguminosae), with special reference to Egyptian species

Chromosome numbers and measurements were recorded in 22 individuals from six populations of six species of Onobrychis , including the Egyptian species and most representatives of section Lophobrychis . The basic number of chromosomes was either x = 7 or x = 8 and the chromosomes were medium to medium-small, ranging in length, from c . 1.6 μm to 2.6 μm. Two new ploidy levels were found, 2 n = 4 x = 28 in O. bobrovii Grossh. and 2 n = 4 x = 32 in O. pulchella Schrenk. The origin of the chromosome numbers, geographical distribution and evolution of the species were assessed. Comparison of the data with those in the literature revealed that the observed interspecific variability among section Lophobrychis can be useful in taxonomic delimitation and demonstrates a complexity of evolution between the diploid and polyploid species. Section Lophobrychis has a comparatively highly derived organization and can be considered as a heterogeneous unit in the genus Onobrychis .  © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 139 , 409–414.     

A new species of the Brazilian genus Chresta (Asteraceae, Vernonieae) from Bahia

A new species of the genus Chresta Vell. ex DC. (Vernonieae, Asteraceae) from the Brazilian state of Bahia is described and illustrated. The new species resembles Chresta pinnatifida (Philipson) H.Rob. but differs in having solitary glomerules, leaf bases clasping the stem and 35–40 capitula per glomerule. It can be distinguished from Chresta harleyii and Chresta martii , the other two species of the genus with pinnately lobed leaves, by the type of pubescence, leaf blade bases and florets number. In addition, a key to distinguish all the species of the genus is presented. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 157 , 587–590.     

Fossil palm flowers in Dominican and Mexican amber

Twelve palm flowers in one piece of Dominican amber and a single flower in a second piece are described as Trithrinax dominicana sp. nov. (Thrinacinae: Coryphoideae), representing the first fossil record of this genus. There are no members of Trithrinax in the Greater Antilles today. Two staminate flowers in Mexican amber are described as Socratea brownii sp. nov. (Iriarteinae: Arecoideae) and represent the first fossils of this genus. A third palm flower in Mexican amber, possibly belonging to the subtribe Euterpeinae, is characterized. © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 138 , 57–61.     

A palynological study of the genus Mentha L. (Lamiaceae)

The pollen morphology and exine structure of 10 Mentha L . species were investigated using light microscopy and scanning electron microscopy. The pollen grains of all 11 species were hexazonocolpate with granular membranes and a circular amb, varying in shape from prolate-spheroidal to suboblate. Different colpus shapes were recognized in M . ×  dumetorum . The exine was bireticulate in section Pulegium , and reticulate in section Menthae . A correlation was found between pollen size and chromosome number. The results indicate that the pollen characters of the genus Mentha are valuable for taxonomic applications and may be useful for classification.  © 2008 Uludag University. Journal compilation © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 157 , 141–154.     

New chromosome counts in the genus Cousinia (Asteraceae) from Iran

Chromosome counts are reported of 38 populations representing 24 species of the genus Cousinia from Iran, one of the main centres of speciation of the genus. Sixteen of the counts are new to science. Our results confirm that Cousinia exhibits a complex dysploid series ranging from x  = 13 to x  = 9. One of the basic chromosome numbers, x  = 9, is new for the genus and must be confirmed. Some considerations on the correlation between chromosome numbers and section classification are made.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 411–419.     

A new species of Hedysarum (Fabaceae) in Iran and other new Hedysarum records

Hedysarum al-shehbazii , a new species endemic to Iran, is described and illustrated. This species belongs to Hedysarum section Multicaulia . It is confined to the western part of Iran (Kermanshah Province), and is known from a single population close to the Iraq frontier, although possibly also growing in the adjoining eastern part of Iraq. The conservation status of this species is 'vulnerable' according to World Conservation Union (IUCN) criteria. In addition, H. varium and H. syricum are reported as new records from a single gathering close to the Turkish frontier. Moreover, H. kotschyi and H. pogonocarpum are transferred from Hedysarum section Crinifera to Hedysarum section Multicaulia .  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 155 , 505–512.     

A new species of Hybanthus (Violaceae) from north-eastern Brazil

A new species of Hybanthus (Violaceae) from north-eastern Brazil is described and illustrated. Hybanthus verrucosus Paula-Souza is endemic to 'caatingas' of Bahia and Alagoas states and is very distinct from all other Brazilian species of the genus, for its anterior petal, which is covered with small wart-like outgrowths. Other distinctive characteristics of the new species and its relationship with a closely related species ( H. atropurpureus (A.St.-Hil.) Taub.) are discussed.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 141 , 503–506.     

Relationships, classification and evolution of Scleranthus (Caryophyllaceae) as inferred from analysis of morphological characters

Study of floral anatomy, micromorphology, palynology and onotogeny has revealed new characters for phylogenetic analysis in the genus Scleranthus . Cladistic analysis of these characters, along with those previously available, suggests that the genus consists of Eurasian/Mediterranean and Australasian sister clades. Gynoecial morphology and development are closely similar in all species, suggesting the genus is monophyletic despite its disjunct northern and southern hemisphere distribution. Variation in pollen:ovule ratios and their implications for the evolution of Scleranthus species are also discussed and it is concluded that a range of breeding strategies intermediate between autogamy and xenogamy exists in the genus. Single-stamened species of Scleranthus are likely to be obligate autogams, despite their comparatively high pollen:ovule ratios in relation to autogamic species of other genera.  © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 140 , 15–29.     

Phyllanthus section Choretropsis (Euphorbiaceae) in Brazil

Section Choretropsis genus Phyllanthus (Euphorbiaceae) is formed by plants whose branches are modified into phylloclades. Despite the suitable characteristics of phylloclades within the Phyllanthus genus, the systematics of these species are poorly understood. Morphological data are presented here to allow future revision of this taxonomic group. The section is represented by nine species distributed in South America, eight of them endemic to Brazil. Our taxonomic studies distinguish the species and propose the synonymization of nine varieties of P. klotzschianus and two varieties of P. flagelliformis based on vegetative and reproductive characters. The diversity of branching and the morphology of phylloclades are discussed.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 150 , 131–164.     

A conifer seedling with two herbicolous fungi from the Baltic amber forest

A Baltic amber inclusion of a fossil spruce seedling of which the lower part of the hypocotyl and the primary root are not preserved is provisionally described as Picea baltica ad int. The remnant of the hypocotyl and the basal parts of the cotyledons are infested by a conidial fungus. Its conidiophores correspond to those of the genus Gonatobotryum Corda. However, the fungus is not assignable to any extant species and is therefore described as a new species, Gonatobotryum piceae . A further infestation, most probably by a stroma-forming anamorph, is visible on the cotyledons of the seedling. Its mode of infestation is similar to that of Sirococcus strobilinus Preuss which occurs in extant spruce seedlings.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 155 , 449–456.     

Astragalus sect. Astragalus (Fabaceae) in Iran

Astragalus rahiminejadii , a new species endemic to Iran, is described and illustrated. This species, which belongs to section Astragalus , is confined to the western part of Iran (Prov. Kermanshah) and is known only from a single population. Seed testa morphology as viewed under the scanning electron microscope is discussed and photomicrographs are provided. In addition, the geographical distribution and ecology of the species belonging to this section are discussed.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 147 , 363–368.     

Okeanomyces, a new genus to accommodate Halosphaeria cucullata (Halosphaeriales, Ascomycota)

The taxonomic affinity of Halosphaeria cucullata to Halosphaeria is reassessed based on a recent collection of this fungus. Halosphaeria cucullata is characterized by immersed, darkly coloured ascomata, clavate asci which deliquesce very early in development, and cylindrical ascospores with or without a polar cap-like appendage at one end. In a phylogenetic analysis of the LSU rDNA sequences from members of the Halosphaeriaceae, H. cucullata did not form a monophyletic clade with H. appendiculata , the type species of the genus. These results suggest that H. cucullata should not be included in Halosphaeria . Okeanomyces gen. nov. is proposed to accommodate this fungus.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 223–229.     

Phylogenetic relationships within Plantago (Plantaginaceae): evidence from nuclear ribosomal ITS and plastid trnL-F sequence data

A molecular phylogenetic study of Plantago L. (Plantaginaceae) analysed nucleotide variation in the internal transcribed spacers (ITS) of nuclear ribosomal and plastid trnL-F regions. Included are 57 Plantago species, with two Aragoa species as the ingroup and three Veronica species as the outgroup. Phylogenetic analysis using maximum parsimony identified five major clades, corresponding to the taxonomic groups Plantago subgenera Plantago, Coronopus, Psyllium, Littorella and Bougueria . Aragoa is sister to genus Plantago . Plantago subgenus Littorella is sister to the other subgenera of Plantago . The results are in general correlated with a morphological phylogenetic study and iridoid glucoside patterns, but Plantago subgenus Albicans is paraphyletic and should be included in Plantago subgenus Psyllium sensu lato to obtain a monophyletic clade with six sections. Plantago section Hymenopsyllium is more closely related to section Gnaphaloides than to section Albicans . Plantago subgenus Bougueria is sister to subgenus Psyllium s.l. section Coronopus in Plantago subgenus Coronopus is subdivided in two series. Only some of the sections can be resolved into series. DNA variation within genus Plantago is high, a result that would not have been predicted on the basis of morphology, which is relatively stereotyped. If we calibrate a molecular clock based on the divergence of P. stauntoni , endemic to New Amsterdam in the southern Indian Ocean, we calculate the time of the split between Plantago and Aragoa to be 7.1 million years ago, which is congruent with the fossil record.  © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 139 , 323–338.     

A new diploid species of Hieracium sect. Pannosa (Asteraceae) from Bulgaria

Hieracium petrovae Vladimirov & Szeląg sp. nov. , a new diploid (2 n  = 18) species in H. sect. Pannosa Zahn, is described and illustrated from the Rhodope Mountains, South Bulgaria, and compared with related taxa. It grows in relict habitats in crevices of limestone rock together with many Balkan endemics. H. petrovae is morphologically similar to taxa from the H. pannosum , H. pilosissimum and H. heldreichii groups (collective species sensu Zahn) to some of which it is a presumed ancestral species.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 150 , 261–265.     

Chromosome counts in Asian Artemisia L. (Asteraceae) species: from diploids to the first report of the highest polyploid in the genus

This work comprises 24 reports of chromosome numbers in 24 Artemisia L. species from Asia. Ten are included in the subgenus Dracunculus Besser and the rest belong to other subgenera. Seven counts are new reports, 14 are consistent with scarce previous ones, and three contribute new ploidy levels. That carried out in A. medioxima reports the highest ploidy level ever counted for the genus (16 x ). There is only one species with x  = 8 as the basic chromosome number. In the remaining x  = 9-based species, ploidy levels range from 2 x to 16 x , illustrating the great role played by polyploidy in the evolution of the genus.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 153 , 301–310.     

Cytogenetic studies on Brazilian Xyris species (Xyridaceae)

Cytological features are presented for the first time for 12 species and one natural hybrid from 16 Brazilian populations of the genus Xyris , including members of two sections ( Xyris and Nematopus ). The results are compared with a review of all available chromosome numbers previously reported for the genus. All analysed species show semi-reticulate interphase nuclei and prophase to prometaphase chromosomes with heterogeneous condensing behaviour. Chromosome numbers varied between 2 n = 26 and 2 n ≈ 108. In Brazil especially, the karyological differentiation of Xyris seems to be generally characterized by dysploid and polyploid increase of the chromosome number, possibly after interspecific hybridization. This is the first cytological study including species of the section Nematopus and the first karyological investigation including South American species of the genus Xyris . © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 138 , 245–252.