Alchemilla boluensis (Rosaceae), a new species from the west Black Sea region (Bolu, Turkey)

Alchemilla boluensis from the west Black Sea region of Turkey is described as a species new to science and illustrated. It belongs to the section Alchemilla , subsection Calycanthum and series Elatae , and is closely related to A. amoena , from which it mainly differs in its stem and leaf features.     

Two new species of Potentilla (Rosaceae) from the Intermountain Region of western U.S.A.

Two new species ofPotentilla from the Intermountain West (U.S.A.) are described and illustrated here for the first time.Potentilla cottamii is known only from the higher quartzite slopes of the Pilot Range and the Raft River Mountains of western Box Elder Co., Utah and adjacent Elko Co., Nevada in the Great Basin. It most closely resemblesP. hyparctica, P. robbinsiana, andP. frigida, which may be its closest living relatives.Potentilla angelliae is known only from one collection from a subalpine meadow on Boulder Mountain of the Aquarius Plateau in southern Utah. It most closely resemblesP. crinita, P. subjuga, andP. bicrenata, the first of which is considered to be its closest relative.     

A new species of Caulanthus (Cruciferae) from Nevada

Caulanthus barnebyi from northern Nevada is described, illustrated, and compared with its nearest relative,C. glaucus S. Wats.     

Ivesia aperta var. canina (Rosaceae), new from California

A new variety,Ivesia aperta var.canina, is described from Dog Valley, Sierra County, Nevada. It differs from the typical variety and approachesI. sericoleuca in its larger, paler yellow petals; longer filaments and styles; and decumbent-ascending vs ascending-erect stems. *** DIRECT SUPPORT *** A01CT146 00004     

The holarctic complex Potentilla fruticosa (Rosaceae)

Potentilla fruticosa L. (Rosaceae) is a complex of large morphological, karyological, geographical and ecological amplitudes. A survey of the distribution of the morphological variation is given and the underlying reasons discussed. Migration paths are also discussed. In southeast central Asia there is a complex in need of further investigation. Outside this area two species should be recognized, a diploid and hermaphrodite species, P. floribunda Pursh, in N America, S Europe and Siberia and a tetraploid and dioecious species, P. fruticosa L., in N Europe and Siberia.     

Hydathode anatomy in Potentilla palustris (Rosaceae)

Guttating leaf teeth of Potentilla palustris plants from Wisconsin, USA, were cleared or processed for plastic sectioning or scanning electron microscopy. Anatomical features include: 1) long slender hydathode area occupying most of the tooth, 2) adaxial pad of small, flat epidermal cells with 50 or more sunken water pores about the size of ordinary abaxial stomates, 3) three converged bundles that extend distally, where their tracheary files are separated by intervening files of xylem parenchyma cells with sinuous walls, 4) adaxial mass of small, loosely arranged epithem cells above the xylem, 5) one slender phloem strand that extends only about a third of the way into the hydathode, and 6) bundle sheath extending distally only abaxially and along the flanks of the hydathode. Potentilla hydathodes differ significantly from non-guttating ones described earlier in Physocarpus (Rosaceae).     

Chrysothamnus eremobius (Asteraceae): A new species from Nevada

Chrysothamnus eremobius, endemic to mountains of southern Nevada, is formally described and illustrated. Morphological and anatomical comparisons are made to related taxa. The new species has many features likePetradoria discoidea (=C. gramineus). Although it bears some similarity toC. depressus andC. vaseyi of sectionPulchelli, C. eremobius is better placed in sectionChrysothamnus nearC. viscidiflorus.     

Rubus ambrosius (Rubus subsect.Rubus, Rosaceae), a new bramble species from the eastern part of Central Europe

Rubus ambrosius Trávní?ek etOklejewicz, a widely distributed species from the eastern part of Central Europe (Czech Republic, Slovakia and Poland), is described.R. ambrosius differs from similar speciesR. sulcatus Vest by more deeply furrowed stems, longer prickles on first-year tems, longer petioles, more prickly petioles, densely hairy leaves beneath and by blunter leaf margin serration with incisions only (2-)1.5–2.5 mm deep. The newly described species is illustrated both by photographs (including the holotype) and a line drawing. A list of localities and a distribution map are presented.     

Leptocereus santamarinae (Cactaceae), a new species from Cuba

Leptocereus santamarinae is newly described as endemic to the dry evergreen forests of the keys and mainland coast of northeastern Cuba. Its closest relationship appears to be withL. sylvestris, of the southeastern coastal woods of Cuba. A key to the twelve known species ofLeptocereus is provided.     

Ayenia saligna (Sterculiaceae), a new species from Colombia

Ayenia saligna from Colombia is described and illustrated. It is remarkable for having foliar nectaries, which now are known to occur in seven of the 75–80 species in the genus. The petals ofAyenia are structurally complex and the inconsistent use of terminology to describe their parts is noted. In addition, the relationship ofA. saligna to other species ofAyenia is discussed.     

Genista valsecchiae (Leguminosae), a new species from Sardinia

Genista valsecchiae from SW Sardinia is described and illustrated as a species new to science. It is very similar toG. ephedroides and can be distinguished by morphological differences of habit and inflorescence. It typically occurs in the garigue or maquis and is widespread in SW Sardinia.     

Allium aetnense (Amaryllidaceae), a new species from Sicily

A new species from Mt Etna (Sicily), Allium aetenense of A. sect. Codonoprasum, is described and illustrated. It is a diploid species (2n = 16) that grows on basaltic rocks in the mountain belt and shows close relationships with A. tenuiflorum of the Italian peninsula. Its morphology, karyology, leaf anatomy, seed coat microsculpturing, ecology and taxonomic position are examined.     

Draba streptobrachia (Brassicaceae), a new species from Colorado

Draba streptobrachia Price is an alpine species endemic to Colorado, U.S.A. It was treated byHitchcock (1941) asDraba spectabilis var.dasycarpa (Schulz) C. L. Hitchc., but is distinct fromD. spectabilis Greene in morphology, habitat, and chromosome number (g = ca 32 inD. streptobrachia, versusg = 10 and 16 inD. spectabilis) and therefore has been raised to the rank of species. Pollen fertility inD. streptobrachia is at or near zero and anthers consistently fail to dehisce, but fertile seeds are still produced, suggesting that the taxon reproduces by agamospermy.     

Marila spiciformis (Bonnetiaceae), a new species from Peru

The new species,Marila spiciformis from Amazonian Peru, is described and illustrated. Relationships with other species are discussed.     

Dioon merolae (Zamiaceae), a new species from Mexico

A new species ofDioon found in northwestern Chiapas is characterized by linear-lanceolate leaflets arising at an acute angle from the rachis, obliquely inserted on it and imbricate.     

Kniphofia monticola (Liliaceae), a new species from Malawi

Kniphofia monticola Blackmore sp. nov., from Mulanje Mountain in Malawi is described. This new species is most closely related to K. splendida E. A. Bruce, a widely distributed species in tropical and southern Africa.     

Dioon holmgrenii (Zamiaceae), a new species from Mexico

A new species ofDioon (Dioon holmgrenii), found on the Pacific slope of southern Oa xaca, is characterized by leaflets which are spinulose especially on the upper margin, elongate and narrow. Distribution and ecology of OaxacanDioon species are reported.     

Penstemon pinorum (Scrophulariaceae), a new species from Utah

Penstemon pinorum, from the Pine Valley Mountains of southwestern Utah, is described and illustrated. It is compared morphologically and ecologically to other members of sectionCristati.