A new section of Protium from the neotropics. Studies in neotropical Burseraceae XIII

Protium sectionPepeanthos, a neotropical group of nine species ranging from Costa Rica to the southern perimeter of Amazonia, is described, as are the group's five new species:P. calendulinum, P. gallosum, P. pecuniosum, P. retusum, andP. urophyllidium. Keys are provided to flowering and to fruiting material. The new section is characterized by a milky resin; lateral leaflet pulvinuli inconspicuous or absent; style short-branched and the stigmas caudiculate and spiculate; and the cotyledons plano-convex.     

Notes on the Burseraceae in central Amazonia,including four new taxa. Studies in neotropical Burseraceae XXVI

The Burseraceae are known to comprise one of the most important tree families in Amazonia, but examination of Burseraceae diversity indicates that this importance is achieved differently in different parts of the Amazon, generally showing greater relative density compared to relative diversity in the east and greater relative diversity compared to relative density in the west, but both high relative density and diversity in central Amazonia. The patterns of relative density may be explained by current climates and by soils, but those of diversity are more likely a function of historical events. Revision of the Burseraceae for two projects near Manaus, Brazil revealed four new taxa. Protium hebetatum is widespread in western Amazonia, but it is one of the most common trees in central and west-central Amazonia; it resembles P. grandifolium. Protium tonyanum is a distinctive new species in poorly resolved sect. Sarcoprotium. Protium paniculatum var. modestum is known thus far only from the vicinity of Manaus plus several localities in the state of Amazonas, Venezuela; a key to the varieties is provided. Dacryodes hopkinsii is one of a group of four species in that genus from Amazonia and the Venezuelan Guayana with relatively large and fleshy flowers that are functionally bisexual. The discovery of these new taxa underscores the biological importance of Manaus and vicinity as a center of diversity for many taxa and exemplifies the synergy between well-designed floristic projects and systematics.     

New taxa and combinations in Protium Burm. f. Studies in neotropical Burseraceae VI

Revision ofProtium in eastern Amazonia and the Guianas yielded one new section, three new species, three new subspecies, and five new combinations in the genus. SectionSarcoprotium Daly is distinguished principally by the cucullate petals with clawed bases and usually with a dorsal thickening produced vertically as an appendage; staminate inflorescences with a few 3-merous flowers; thecae of the anthers completely separated by the connective and the dehiscence latero-introrse; and fruit ellipsoid when only one pyrene develops.     

Two new species of Protium from French Guiana. Studies in neotropical Burseraceae VIII

Revision of Protium in French Guiana has revealed two new species. Protium gallicum is related to P. aracouchini (Aubl.) Marchand and P. elegans Engl., although its fruits resemble those of P. plagiocarpium Bénoist. Protium inodorum, which also occurs in northern Pará, Brazil, is related to P. pallidum Cuatrec. and P. cuneatum Swart; it is known only from flowers and very young fruits. Even in relatively well-known regions of tropical forest, botanical exploration continues to yield new taxa.     

Dacryodes edilsonii, a new species from southwestern Amazonia. Studies in neotropical Burseraceae XII

Dacryodes edilsonii Daly (Burseraceae) is one of at least 14 still undescribed neotropical species in the genus; it is also one of a large number of new species emerging from intensified botanical exploration of the Brazilian state of Acre in southwestern Amazonia. The new species is easily distinguished from most other Neotropical species of the genus by its usually densely long-pubescent petiole, rachis, petiolules, and abaxial midvein.     

A synopsis of the neotropical genus Pentaplaris, with remarks on its systematic position within core Malvales

Pentaplaris davidsmithii from Peru and Bolivia andP. huaoranica from Ecuador are described and compared to the only other species previously known in the genus,P. doroteae from Costa Rica. Morphological and palynological characters support the inclusion ofPentaplaris in core Malvales while suggesting that the original assumption that the genus belonged in Tiliaceae-Brownlowieae cannot be maintained.Pentaplaris, which comprises three isolated and evidently rare species, probably belongs to the malvoid-bombacoid alliance, but its position within this clade ramains unresolved.     

A synopsis of the neotropical species of Dalechampia (Euphorbiaceae)

WEBSTER, G. L. & ARMBRUSTER, W. S., 1991. A synopsis of the neotropical species of Dalechampia ( Euphorbiaceae ). The characters used in inferring phylogenetic relationship in Dalechampia are discussed, and a consistent terminology is devised for the parts of the distinctive pseudanthial inflorescences. The infrageneric classification is radically modified, with the 92 provisionally accepted binomials for the neotropical taxa referred to six sections: Rhopalostylis, Dioscoreifoliae, Cremophyllum, Coriaceae, Tiliifoliae and Dalechampia. As here interpreted, section Dalechampia includes 53 species in five subsections; one new subsection, Convolvuloides , is described.     

A taxonomic synopsis of the genus Campeiostachys Drobov

We have classified 11 species recently recognized as belonging to the genus Elymus into a resurrected and legitimate genus Campeiostachys Drobov according to the International Code of Botanical Nomenclature. Our action is based on the rationale of monophyly, discrimination, and practicality discussed in detail. Currently Elymus contains a vast number of species with different genomes which often, but not always, can be differentiated by cytological and molecular features, but are difficult to separate by tr...     

Bursera pereirae,a new species and generic record for the Cerrado complex of Brazil. Studies in neotropical Burseraceae XVIII

Bursera pereirae is described and illustrated, and an updated key to Bursera in South America is provided. This new species, which should be considered threatened, is the first record of Bursera for the Cerrado region and the only species of tribe Bursereae endemic to Brazil.     

Notes on Dacryodes Vahl, including a new species from the Rio Negro basin in Amazonia. Studies in neotropical Burseraceae. XI

Dacryodes is a poorly known pantropical genus of some 67 species; a new revision now under way reveals that the Neotropical region is home to at least 36 species, 14 of them undescribed. The genus is introduced with a brief taxonomic history, a presentation of the putative differences fromPseudodacryodes, a discussion of the infrageneric classification, and a preliminary comparison of Neo- and Paleotropical taxa. Characteristics that make the genus difficult to study are pointed out.Dacryodes negrensis, the first in a series of new taxa, is described and illustrated.     

A synopsis of the genus allomarkgrafia (Apocynaceae)

The nine species of the genusAllomarkgrafia are treated synoptically, with a review of their systematics and nomenclature. Two new species,Allomarkgrafia ecuatoriana andA. insignis, and a new combination,Allomarkgrafia campanulata, are proposed here.     

A new peri-Amazonian species of <Emphasis Type="Italic">Protium</Emphasis>. Studies in neotropical Burseraceae XXI

Protium decorum is described and illustrated. The distribution of this new taxon exemplifies a rather common pattern around the southern periphery of the Amazon.     

A synopsis of the genus Atypus (Araneae, Atypidae)

Twelve of sixteen Atypus species previously described, and one undescribed, are examined. Atypus javanus Thorell is re-diagnosed and the male is described. The vulva of this species, and of A. coreanus Kim and A. karschi Dönitz, arc illustrated for the first time. The taxonomic characters given by Kraus & Baur [ Verh, naturw. Ver. Hamb. 17 : 85–116(1974)] and additional details of male-and female genital organs are discussed. A granular texture on male chelicerae and front legs, presumably a stridulatory apparatus, is noted and used for distinguishing species. A deep cymbial pit of unknown function is illustrated and discussed. Specific character combinations for the species examined are presented in a table. Notes on relationships, habitat, zoogeography, web, phenology and development are given.     

Revision of Plerandra (Araliaceae). I. A synopsis of the genus with an expanded circumscription and a new infrageneric classification

Phylogenetic studies have demonstrated that Schefflera, the largest genus of Araliaceae, is grossly polyphyletic, comprising five distinct clades within the family. In an effort to establish monophyletic genera among the elements that currently comprise Schefflera, the genus Plerandra is expanded to encompass all of the members of one of these clades. In this synoptical revision, a new infrageneric classification is presented (along with a key) in which six subgenera are recognized. Four of these subgenera are newly described (Plerandra subgenera Canacoschefflera, Costatae, Gabriellarum, and Veilloniorum) and a fifth represents a new combination (Plerandra subg. Dizygotheca). A total of 33 species (one with two subspecies) are accepted, one of which is newly described (P. veilloniorum), and 22 new combinations are made (P. actinostigma, P. baillonii, P. cabalionii, P. costata, P. crassipes, P. elegantissima, P. elongata, P. emiliana, P. gabriellae, P. leptophylla, P. nono, P. osyana, P. osyana subsp. toto, P. pachyphylla, P. pancheri, P. plerandroides, P. polydactylis, P. reginae, P. seemanniana, P. tannae, P. vanuatua, P. veitchii). Neotypes are provided for six accepted names and one heterotypic synonym, and lectotypes are designated for 13 accepted names and 16 heterotypic synonyms. For each accepted species, full synonymy is provided along with geographic range and notes.