A synopsis of the genus Mandevilla (Apocynaceae) in Mexico and Central America

The 19 species of the genus Mandevilla in Mexico and Central America are treated synoptically. New synonymy is provided and a new species, Mandevilla rigidifolia, is described.     

A taxonomic study of Salix sections Mexicanae and Viminella subsection Sitchenses (Salicaceae) in North America

The recently recognized western North American sectionsBrewerianae, Mexicanae, andSitchenses in the genusSalix were studied in the field and herbarium. SectionsSitchenses andBrewerianae are here combined and placed under sectionViminella as a subsection. Three species and an additional variety are recognized in subsectionSitchenses and seven species are recognized in sectionMexicanae. Keys for identification and distribution maps are provided.     

Five new species of Heteropterys (Malpighiaceae) from Central and South America

Five-new taxa ofHeteropterys H. B. K. subsect.Aptychia Nied. are described, illustrated, and mapped:H. andina from Peru;H. minutiflora from Costa Rica; andH. bullata, H. capixaba, andH. oberdanii, from the Atlantic coastal forest of Brazil. The affinities and diagnostic characters of each species are discussed.     

Bryocamptus pilosus n. sp. (Copepoda: Harpacticoida) from North America

A new species of Bryocamptus from North America, B. pilosus n. sp., is described and illustrated. Some remarks are made on the occurrence of a specific piliform seta on the ventral side of the caudal ramus in the vejdovskyi species group.     

A synoptic revision of Dacryodes (Burseraceae) in Africa, with a new species from Central Africa

Summary  A synoptic revision is presented for the genus Dacryodes Vahl in Africa. The studies are based on examination of herbarium material. Eighteen species are recognised, including two not well known due to poor material. The new species Dacryodes villiersiana Onana is described and illustrated. The conservation status of the species is discussed following the categories and criteria of IUCN (2001).     

Microsatellite analysis of relationships among North American plums (Prunus sect. Prunocerasus, Rosaceae)

Fifteen microsatellite primer pairs developed in sweet cherry and peach were used to explore genetic relationships among North American plums (Prunus section Prunocerasus). In all, 186 putative alleles were detected with a mean value of 12.4 per locus. The Jaccard coefficient of similarity was calculated between all pairs of accessions and their genetic similarities represented by a UPGMA dendrogram. Despite the apparent closeness among native American plums as evidenced by their ability to hybridize freely and their very similar ITS and trnL-trnF nucleotide sequences, all pairs of accessions among the North American plums shared fewer than half of their alleles. Some of the relationships suggested by the UPGMA dendrogram are congruent with current taxonomic hypotheses, but others are difficult to interpret. Further resolution of relationships among American plums will require molecular markers more variable than ITS yet less variable than microsatellites.     

Magnolia (Magnoliaceae) in Mexico and Central America: a synopsis

As a result of a recent alpha-taxonomic study of the genusMagnolia s. str. in Mexico and Central America, four new species and four new subspecies ofMagnolia sect.Theorhodon are proposed, includingM. iltisiana, M. panamensis, M. tamaulipana, M. sororum subsp.lutea, andM. pacifica, consisting of three subspecies:pacifica, pugana, andtarahumara. Additionally, a new combination,M. guatemalensis subsp.hondurensis, is made, and a new section,M. sect.Splendentes, is erected for the Caribbean species. The results have implications for understandingMagnolia biogeography, andM. tamaulipana has potential for horticulture in temperate zones. Keys to genera, sections, and species, and maps of species distributions are presented.Magnolia grandiflora L. andM. schiedeana Schltdl. are lectotypified. Como resultado de un estudio alfa-taxonómico reciente del géneroMagnolia s.str. en México y Centro América, se proponen cuatro especies nuevas y cuatro subespecies nuevas deMagnolia sect.Theorhodon, incluyendoM. iltisiana, M. panamensis, M. tamaulipana, M. sororum subsp.lutea y.M. pacifica, la última consiste de tres subespecies:pacifica, pugana ytarahumara. Adicionalmente, se hace la combinaciónM. guatemalensis subsp.hondurensis y se erigeM. sect.Splendentes para las especies del Caribe. Los hallazgos tienen implicaciones en el entendimiento de la biogeografia deMagnolia y.M. tamaulipana tiene potencial en la horticultura de zonas templadas. Se presentan claves para géneros, secciones y especies, y mapas de distribución para las especies.Magnolia grandiflora L. yM. schiedeana Schltdl. son lectotipificadas.     

北美洲当归属(伞形科)植物花粉形态特征研究

花粉形态特征可为伞形科当归属的分类鉴定与亲缘关系研究提供重要依据;北美洲当归属植物是该属的重要分支分群,但其花粉学研究却鲜受关注。为进一步充实孢粉学研究资料,使用光学显微镜与扫描电子显微镜对北美洲当归属26种44个居群的花粉形态和外壁纹饰进行观察,并用SketchUp软件对花粉极轴及赤道轴长度、体积指数和纹饰密度等特征进行测量分析和定量定义。研究结果显示:(1)供试花粉包含椭圆形、近长方形、超长方形与超长方形(赤道缢缩)4种形状;(2)花粉极轴长度为21.1~32.0μm,赤道轴长度为10.6~17.1μm,极轴与赤道轴的比值为1.5~2.8,体积指数为15.8~23.3;(3)花粉赤道区外壁纹饰分为3类,包括长条状脑纹、短棒状脑纹以及片状脑纹,排列或密集或稀疏,其中3个物种的纹饰在极区变平滑;(4)根据上述形态特征,可将供试花粉划分为4级3大类15小类。研究结果表明,总体上北美洲当归属植物花粉的形态特征的多态性低于东亚当归属植物;花粉形状与赤道区外壁纹饰具有较高的种内一致性,花粉中部是否凸出以及纹饰类型、密集程度、附属物等特征则存在一定程度的种内差异。该研究进一步充实了当归属的孢粉学研究资料,花粉形态特征能够为该类群的分类鉴定与亲缘关系研究提供重要依据,可作为形态分类学和分子分类学的有力补充。     

The Aristida pansa complex and a key to the Divaricatae group of North America (Gramineae: Aristideae)

Variation in lateral awn length and pulvini development is described for A. pansa and A. gypsophila. The two species are distinguished by lateral awn development. Within each species, forms are based on pulvini development. Three new forms are described (A. pansa f. contracta; A. gypsophila f. gypsophiloides and f. diffusa), A. dissita is reduced to a form of A. pansa, and A. tehuacanensis is considered synonymous with A. pansa f. dissita. Keys, illustrations, and maps are provided.     

Sorex rohweri sp. nov. (Mammalia, Soricidae) from northwestern North America

Sorex rohweri sp. nov. is described on the basis of a series of specimens from the Olympic Peninsula and adjacent western regions of Washington State, USA, and southwestern British Columbia, Canada. It has been misidentified as Sorex cinereus Kerr, 1792, which occurs in the Cascade Range in west-central Washington, in coastal British Columbia, and regions farther to the northeast. The new species is distinguished from S. cinereus by numerous morphological characters: differences in craniodental dimensions; different location and form of the medial tines of the upper incisors; presence of patent postmandibular foramina; different intensity and distribution of dental pigmentation; and different form of the glans penis, along with other details. The combination of characters also separates it from sympatric species of Sorex. Phylogenetic inference of cytochrome b sequences from two specimens of the proposed new species shows them to be distinct from Sorex cinereus and from five sympatric Sorex species, supporting their designation as members of a new species.     

Phylogeny and biogeography of Sassafras (Lauraceae) disjunct between eastern Asia and eastern North America

Sassafras (Lauraceae) consists of three species disjunct between eastern Asia (S. tzumu and S. randaiense) and eastern North America (S. albidum). Phylogenetic analysis based on sequences of nuclear ribosomal ITS and three chloroplast non-coding regions (rpl16, trnL-F, and psbA-trnH) showed that Sassafras is monophyletic and that the eastern North American S. albidum is sister to the clade of its two eastern Asian counterparts. Their intercontinental divergence was estimated to be 13.80 ± 2.29−16.69 ± 2.52 million years ago (mya) using the penalized likelihood method with the ITS and three chloroplast markers. Biogeographic analyses combined with fossil evidence suggest that Sassafras has a relict distribution in the Northern Hemisphere without a Gondwanan link. The divergence time of the two eastern Asian species (the continental Chinese Sassafras tzumu and S. randaiense endemic to Taiwan) is estimated to be 0.61 ± 0.75−2.23 ± 0.76 mya. Sassafras randaiense from Taiwan was most likely derived from an ancestor from continental China.     

中国蔷薇科蕨麻属新组合

在编研《中国生物物种名录》第一卷第五分册(蔷薇科–叶下珠科)的过程中,根据最新的研究结果提出国产蔷薇科蕨麻属植物的12个新组合。     

A cytological study on Kelloggia (Rubiaceae), an intercontinental disjunct genus between eastern Asia and western North America

A cytological study was carried out for the first time on four populations of the only two species of Kelloggia (Rubiaceae), which occur disjunctly in eastern Asia (K. chinensis Franch.) and western North America (K. galioides Torr.). The consistent mitotic prophase chromosome condensation pattern and interphase nuclei type were determined for both species. The chromosome base number of the genus is suggested to be x=11. The karyotype of 2n=22=2x=16m+6sm was examined for both species. The karyotypical asymmetry of 1A and 2A was found in K. chinensis and K. galioides, respectively. According to the predominant evolutionary direction of karyotype asymmetry in angiosperms, K. galioides (2A) seems slightly more evolved than K. chinensis (1A). Our finding is consistent with the hypothesis of the Old World origin of Kelloggia based on molecular study.     

Dalbergia prazeri Prain(豆科)之考证

在发表Dalbergia prazeri Prain时Prain曾认为其与托叶黄檀(D.stipulacea Roxb.)近缘,只是该种小叶背面疏被微柔毛,花萼被硬毛与托叶黄檀不同,同时又指出其荚果也与后者不同,但是并没有解释其不同点。之后Prain又将其归并入奥氏黄檀(D.oliveri Gamble ex Prain),亦未给出相应的理由。经研究D.prazeri Prain与南岭黄檀(D.assamica Benth.)为同种,而被归并入后者。Prain发表该种时引证Prazer s.n.为模式,但并没有指定主模式。涉及该种的Prazer s.n.的标本共有6份,该文将藏于印度国立标本馆加尔各答馆(CAL),条形码为CAL0000012326(CAL标本号131311)的标本指定为后选模式(lectotype),其余分别藏于加尔各答标本馆的4份及英国皇家植物园邱园标本馆(K)的1份为等后选模式(isolectotype)。