A new species of Exostyles (Leguminosae, Papilionoideae, Swartzieae s.l.), from Paraná State, Brazil

A new species Exostyles godoyensis Soares-Silva & Mansano (Leguminosae, Papilionoideae, Swartzieae), endemic to Paraná state in southern Brazil, is described and illustrated. The new species is distinct from all the other species of Exostyles in having a leaf with up to five leaflets, while the other species have at least seven leaflets per leaf. The new species is distinct from Exostyles amazonica Yakovlev in its longer stamen filaments and ovary stipe and from E. glabra Vogel and E. venusta Schott by its shorter anthers. In addition to these morphological characters E. godoyensis has a disjunct geographical distribution.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 103–106.     

Isoetes fluitans sp. nov.: the identity of Spanish plants of 'I. longissimum'

Recent revision of North African specimens of Isoetes velata A. Braun and the closely related taxon I. longissimum Bory, together with Spanish material conventionally designated I. longissimum , suggests that the Spanish specimens constitute a new species, I. fluitans . This is described and illustrated. The North African taxon I. longissimum is probably not specifically distinct from I. velata .  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 231–236.     

A new species of Arabis (Brassicaceae) from inner Anatolia

A new species of Arabis L., A. erikii Mutlu sp. nov. , is described and illustrated. The species is restricted to inner Anatolia, south-west of Sivas. It grows on steppes. Diagnostic morphological characters are given for discrimination from the most similar taxa.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 145 , 251–256.     

Two new species of Sicyos (Cucurbitaceae) from Guerrero and Oaxaca, Mexico

Two new species of Sicyos from Mexico are described and illustrated: Sicyos cordifolius from the state of Guerrero, which belongs to the group with dry, armed fruits, and Sicyos bulbosus from the state of Oaxaca, which belongs to the group with fleshy, unarmed fruits. Sicyos cordifolius is quite different from the rest of the species previously described. Although S. bulbosus is very similar to S. galeottii Cogn., it is clearly different in receptacle shape and size.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 145 , 373–378.     

A new endemic species of Epipactis (Orchidaceae) from north-east Portugal

A new species, Epipactis duriensis Bernardos, D. Tyteca, Revuelta & Amich is described and illustrated from north-east Portugal. Notes on its distribution, ecology, karyology, micromorphology and taxonomic relationships are presented as well as molecular data based on ITS analysis. A list of diagnostic differences between E. duriensis and the closely related species E. lusitanica and E. tremolsii is provided.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 145 , 239–249.     

The lichenicolous Opegrapha species (Roccellaceae, Ascomycota) with 3-septate ascospores on Pertusaria and Ochrolechia

The Opegrapha species with 3-septate ascospores growing on Pertusaria and Ochrolechia are revised. Two species are recognized: Opegrapha anomea (of which O. pertusariae , O. quaternella , O. wetmorei and possibly Leciographa weissii are considered to be synonyms), and O. blakii Ertz & Diederich sp. nov. described from a sterile lichen with an Ochrolechia -like thallus, known from Ecuador and Venezuela. Opegrapha anomea and several related lichenicolous species with roundish or irregular, often multilocular ascomata are morphologically intermediate between Opegrapha and Plectocarpon , and might represent a distinct genus.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 144, 235−241.     

A new species of Nigella (Ranunculaceae) from Turkey

Nigella turcica a new species endemic to north-eastern Turkey is described and illustrated. Morphological differences between the species and the closely related species, N. sativa , are discussed and the IUCN threatened category is proposed. A distribution map of the new species and its related taxon is given.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 251–255.     

A new species of Ocimum (Lamiaceae) from Swaziland

A new species of Ocimum , O. motjaneanum McCallum & K. Balkwill, endemic to serpentine soils in the north-west of Swaziland, is described and compared with O. obovatum, the species it most closely resembles. It has a very localized distribution with an area of occupancy under threat of encroachment by exotic trees and development, which makes it critically endangered (CR B1a + b(iii)) using the IUCN guidelines. We recommend habitat protection and incorporation of one site into an existing nature reserve to assure the continuation of this species.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 145 , 379–383.     

The cytological origin of the polyads and their significance in the reproductive biology of Mimosa bimucronata

The mechanism of polyad formation in Mimosa bimucronata (DC.) Kuntze is described and its significance in the reproductive biology is discussed. In this species c . 500 complexes of two coupled pollen mother cells (PMCs) per pollen sac are formed after the last mitotic division of the sporogenous tissue. All the pollen grains of each complex remain attached and form a bitetrad. This mechanism leads to the formation of many polyads per pollen sac. On this basis, we propose that in Mimosa the number of pollen grains per polyad (eight or 16) is determined by the number of cells that remain attached after the last mitotic divisions of the sporogenous tissue. Concerning the biological significance of the polyads in M. bimucronata , we find that the number of pollen grains per polyad is correlated with the number of ovules per ovary, and that the internal dimensions of the pit-shaped stigma are sufficient just for one polyad to be localized in it. Based on the number of polyads per flower this species has a high pollen/ovule ratio characteristic of xenogamous plants, in opposition to that expected for plants with composite pollen dispersal units. In contrast, it has low pollination efficiency, low fruit set, a 1/1 relationship between the pollen grains of a polyad and the number of ovules per ovary, and high seed set per fruit. These facts support the hypothesis that the occurrence of polyads in M. bimucronata would be an adaptation helping to ensure high seed set following a single cross pollination event.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 144 , 343–349.     

The genus Maesa (Maesaceae) in the Philippines

A comprehensive taxonomic revision of the genus Maesa Forssk. (Maesaceae) occurring in the Philippines is presented for the first time. Thirteen species are recognized, including a newly described species, M. stonei , which is most similar to M. reflexa . Several previously used names are reduced to synonymy, including M. pachyphylla and M. undulata (both reduced to synonymy with M. cumingii ), and M. elmeri , M. laxa and M. ramosii (all reduced to synonymy with M. indica ). Extensive lectotypification has been necessary due to the destruction of many type specimens, particularly those of C. Mez (in B) and E. D. Merrill (in PNH). The conservation status of each species is determined using the IUCN red list categories and criteria.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 145 , 17–43.     

Clarification of the name Nothofagus alpina and a new epithet for a Nothofagus hybrid

Arguments in favour of using Nothofagus alpina (Poepp. & Endl.) Oerst. (Fagaceae) rather than N. procera Oerst. or N. nervosa (Phil.) Krasser as the correct name for rauli are presented. We also refute suggestions that N. alpina is based on hybrid material. The hybrid of N. alpina with N. obliqua (Mirb.) Blume is formally described as N . ×  dodecaphleps Mike L. Grant & E. J. Clement and a key to the deciduous taxa of Nothofagus is provided.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 447–451.     

Two new species of Multiclavula (lichenized basidiomycetes) from savanna soils in Rwanda (East Africa)

Two new species of Multiclavula are described from Rwanda: M. akagerae , with a thallus consisting of turgescent glomerules, and M. rugaramae , with a thallus composed of flattened, rounded, marginate, and dispersed squamules. They grow on soil in frequently burned savannas or on lateritic soils in eastern Rwanda. The genus Lepidostroma should probably be reduced into synonymy with Multiclavula .  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 155 , 457–465.     

Speciation in Darwin's darklings: taxonomy and evolution of Stomion beetles in the Galápagos Islands, Ecuador (Insecta: Coleoptera: Tenebrionidae)

Stomion is one of three speciose and taxonomically difficult genera of flightless Darwin's darkling beetles of the Galápagos Islands. The previously named species and subspecies of Stomion are analysed by morphometric and cladistic methods. Eleven species are here recognized, which probably descended from colonization by a single ancestral species. Cladistic analysis yielded two weakly supported clades that are different from previously published morphological and allozyme genotype groups. Phenotypic and genotypic characters may be evolving independently. There is much within-species variation, but there is no compelling evidence of adaptive radiation in Stomion , in contrast to that in the famous Darwin's finches. The analyses show the need for changes in morpho-species taxonomy: S. punctipennis Van Dyke ( syn. nov. ) is elevated to full species from a subspecies of S. galapagoensis Waterhouse. There is no evidence to support the validity of: S. laevigatum santacruzensi Franz ( syn. nov. ), synonomized here under S. l. laevigatum Waterhouse; S. galapagoensis leleupi Kaszab ( syn. nov. ), synonomized here under S. linelli Blair; S. galapagoensis pinzoni Franz ( syn. nov. ), synonomized here under S. obesum Van Dyke. S. genovesa sp. nov. is described from Genovesa Island. Lectotypes are designated for S. galapagoensis Waterhouse, S. laevigatum Waterhouse and S. helopoides Waterhouse .   © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society , 2004, 141 , 135–152.     

A new species of Ceratozamia (Zamiaceae) from Tabasco and Chiapas, Mexico

Ceratozamia becerrae sp. nov. is described and illustrated. This species from Tabasco and Chiapas has affinity with C. miqueliana H. Wendl. from Veracruz and Chiapas, but differs in morphology and habit of leaves, leaflets, male and female strobili and trunk. Ceratozamia becerrae is considered part of the C. miqueliana species complex that includes C. miqueliana, C. euryphyllidia Vázq.Torres, Sabato & Stevenson and C. zoquorum Pérez-Farrera, Vovides & Iglesias. The geographical range of this species complex is southern Veracruz, Tabasco and northern Chiapas in tropical rain forests.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 123–128.     

Comparative floral structure and systematics of Pelagodoxa and Sommieria (Arecaceae)

Floral structure is compared in Pelagodoxa and Sommieria (Arecaceae, Arecoideae). Male flowers have three free, imbricate sepals, three basally congenitally united and apically valvate petals, and six stamens. Anthers are dorsifixed and dehiscence introrse. The sterile gynoecium is tricarpellate. Female flowers have three free, imbricate sepals and three free, imbricate petals, which are slightly fused with the sepals at the base. Four to six staminodes are congenitally united at the base and fused with the ovary for a short distance. The gynoecium is syncarpous. Carpels are almost equal in early development; later the gynoecium becomes pseudomonomerous. The three stigmatic branches are equally developed, apical and sessile. The carpels are (syn-)ascidiate up to the level of the placenta and (sym-)plicate above. Each carpel has one ovule, in the sterile carpels it is aborted at anthesis. The fertile ovule is erect up to anthesis and pendant afterwards because of the bulging out of the ovary. Pollen tube transmitting tracts (PTTT) encompass the secretory epidermis of the ventral slits of each carpel. Floral structure in Pelagodoxa and Sommieria supports the sister group relationship between the two genera suggested in recent molecular phylogenies and reflects their close relationships to a major clade of pseudomonomerous arecoid palms from the Indo-Pacific region.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 27–39.