Tropical lowland mosses disjunct between Africa and the Americas, including Calyptothecium planifrons (Ren. & Par.) Argent, new to the Western Hemisphere

Calyptothecium planifrons (Ren. & Par.) Argent is reported new to the Western Hemisphere based on two recent collections from Brazilian Amazonia, in Pará and Rondônia; C. planifrons was originally described from Madagascar. Forteen Other species of mosses with apparently disjunct distributions between tropical Africa and tropical America are also discussed. It is likely that mos or all of this species discussed will prove to have wider distributions in the tropics when world-wide revisions are carried out.

A new species of Pithecellobiutn (MIMOSACEAE INGEAE) from Brazilian Amazonia

Phithecellobium prancei, related to T. simabifolium Benth. and P. spruceanum Benth., is described and figured from specimens collected on white sand savannas along rio Aracá in northern Amazonas, Brazil. Its relationships within sect. Samanea ser. Coriaceae Benth., a group due for generic segregation from Pithecellobium sens. lat., are discussed.

A NEW SPECIES OF Rhacodiaptomus Kiefer, 1936, FROM THE BRAZILIAN AMAZON (CRUSTACEA:COPEPODA: CALANOIDA)

A new species of Calanoid copepod, Rhacodiaptomus besti,is described from material collected in the Igarapé São Pedro, Rio Jamari, State of Rondônia, and Lago Amanã, Rio Japurá, State of Amazonas, in Western Amazonia. A detailed morphological analysis of the species was undertaken in order to provide a basis for future studies on inter and intrageneric relationships.

NOMENCLATURAL AND CRITICAL NOTES ON SOME BRAZILIAN SPECIES OF Paspalum (POACEAE: PANICEAE)

A critical analysis of the type collections of 39 species names of Paspalum L. (Poaceae: Paniceae) from Brazil described by Swallen is presented along with comments based on more recent gatherings of the species. Eighteen new synonyms are proposed.

Vanamea GEN. NOV. FOR Livoneca symmetricaVAN NAME,1925, (CRUSTACEA, ISOPODA, CYMOTHOIDAE) AND A REDESCRIPTION OF THE SPECIES BASED ON SPECIMENS FROM BRAZILIAN PIRANHAS

Studies of the cymothoid isopod Livoneca symmetricaVan Name, 1925, showed that this species has characters that preclude its inclusion in LivonecaLeach, 1818, or in any other known genus. The species is redescribed on the basis of male and female specimens from the mouth cavities of Amazonian piranhas (Serrasalmus spilopleura(Kner) and S. elongatusKner) and Vanameagen. nov. is proposed for it. The new genus is defined as having: a cephalon that is not immersed in pereonite 1; mandibles that are "foot-shaped" and without incisors, pereopods that are long and unequal in size and shape; a pleon that is not immersed in the pereon; and a pleotelson that is inflated anteriorly and medially.

Wood specific gravity of trees and forest types in the southern Peruvian Amazon

Estimates of terrestrial biomass depend critically on reliable information about the specific gravity of the wood of forest trees. The study reported on here was carried out in the southern Peruvian Amazon and involved collection of wood samples from trees (70 spp.) in intact forest stands. Results demonstrate the high degree of variability in specific gravity (ovendry weight/green volume) in trees at single locations. Three forest types (swamp, high terrace forest with alluvial soil, and sandy-soil forest) had values close to the average reported for tropical forest woods (.69). Two early successional forest types, which make up as much as 12% of the total vegetated area in this part of the Amazon, had values significantly lower (.40). An increase in specific gravity with increasing age of the tree, which has been reported in some spe cies of tropical-forest woods, is seen in a positive relationship between specific gravity and di ameter for a species prevalent in one plot. Increases in specific gravity with tree and forest age may be significant in estimating changes in carbon stores over time.

On the Brazilian Prosierola (Hymenoptera, Bethylidae), with description of a new species from Amazonas, Brazil

Prosierola rotunda sp. nov. from northern Brazil is described and illustrated. Additional specimens of P. lata (Cameron, 1888) were examined with species variation analyzed and new distribution data are added.

Cross-scale determinants of palm species distribution

We investigate palm species distribution, richness and abundance along the Mokoti, a seasonally-dry river of southeastern Amazon and compare it to the patterns observed at a large scale, comprising the entire Brazilian territory. A total of 694 palms belonging to 10 species were sampled at the Mokoti River basin. Although the species showed diverse distribution patterns, we found that local palm abundance, richness and tree basal area were significantly higher from the hills to the bottomlands of the study region, revealing a positive association of these measures with moisture. The analyses at the larger spatial scale also showed a strong influence of vapor pressure (a measure of moisture content of the air, in turn modulated by temperature) and seasonality in temperature: the richest regions were those where temperature and humidity were simultaneously high, and which also presented a lower degree of seasonality in temperature. These results indicate that the distribution of palms seems to be strongly associated with climatic variables, supporting the idea that, by 'putting all the eggs in one basket' (a consequence of survival depending on the preservation of a single irreplaceable bud), palms have become vulnerable to extreme environmental conditions. Hence, their distribution is concentrated in those tropical and sub-tropical regions with constant conditions of (mild to high) temperature and moisture all year round.

Outcrossing rate of Couratari multiflora (J.Smith) Eyma (Lecythidaceae), a low-density tropical tree species from a central Amazonian rainforest

A multilocus mixed-mating model was used to evaluate the mating system of a population of Couratari multiflora, an emergent tree species found in low densities (1 individual/10 ha) in lowland forests of central Amazonia. We surveyed and observed phenologically 41 trees in an area of 400 ha. From these, only four mother trees were analyzed here because few of them set fruits, which also suffered high predation. No difference was observed between the population multilocus outcrossing rate (t mp = 0.953 ± 0.040) and the average single locus rate (t sp = 0.968 ± 0.132). The four mother trees were highly outcrossed (t m ~ 1). Two out of five loci showed departures from the Hardy-Weinberg Equilibrium (HWE) expectations, and the same results occurred with the mixed-mating model. Besides the low number of trees analyzed, the proportion of loci in HWE suggests random mating in the population. However, the pollen pool was heterogeneous among families, probably due to both the small sample number and the flowering of trees at different times of the flowering season. Reproductive phenology of the population and the results presented here suggest, at least for part of the population, a long-distance pollen movement, around 1,000 m.

Leaf anatomical features of three Theobroma species (Malvaceae s.l.) native to the Brazilian Amazon

Theobroma species have economic importance due to their use in the cosmetic and food industries, mainly in the production of chocolate. However, the anatomy of their vegetative structures remains poorly studied. The goal of this study was to describe the anatomical features of Theobroma grandiflorum, T. speciosum and T. subincanum to contribute to the biological knowledge of these species, as well as provide support to the biotechnological studies of native fruit plants of the Amazon. Leaves at different developmental stages were collected and analyzed under light microscopy and scanning electron microscopy. Sessile and stalked stellate trichomes and digitiform glandular trichomes were observed in the expanded leaves of T. grandiflorum and T. subincanum. These species were also similar in the morphology of the midrib, the organization of the mesophyll and the presence of starch grains in the midrib pith cells. Claviform glandular trichomes and mucilage cells in the epidermis occurred only in the expanded leaves of T. speciosum. The presence of mucilage secretory trichomes in shoot apices (colleters) of all species is a new finding for the genus Theobroma.

Rotary peeling yield of Schizolobium amazonicum (Leguminosae - Caesalpinioideae)

The tropical tree Schizolobium amazonicum is native from the Amazonian forest, naturally occurring in Brazil, Peru and Colombia. This work aimed to study the veneer yield made from this species. For this purpose, 50 logs from S. amazonicum were rotary peeled in a plywood industry installed in Brazilian Amazon region. The results indicated that S. amazonicum had a peeling yield similar or even higher than those usually obtained for species traditionally used for this purpose in Brazil, like those of Pinus and Eucalyptus. It was also observed that the dendrometric parameters of the log can be used to estimate the peeling yield in this species.

Envia garciai, a new genus and species of mygalomorph spiders (Araneae, Microstigmatidae) from Brazilian Amazonia

The genus Envia, comprising only the new species Envia garciai, is proposed. These small mygalomorph spiders were abundantly collected in soil cores and litter samples in primary rain forests near Manaus, Amazonas, Brazil.

Five new Brazilian species of the genus Trybliophorus (Orthoptera, Romaleidae)

The new species Trybliophorus amazonicus, T. nigrus, T. rubricerus, T. olivaceus and T. paraensis from Amazonian region are described. Illustrations of male and female genitalia, as well as a map showing the geographical distribution of the species are included.

Morphology of three Brazilian species of Semiotus (Coleoptera, Elateridae, Semiotinae)

The morphology of Semiotus distinctus (Herbst, 1806), S. intermedius (Herbst, 1806) and S. ligneus (Linnaeus, 1767), including mouthparts and male and female genitalia, is described and illustrated. A comparative analysis of the characters related to the external morphology, mouthparts and male and female genitalia is also included.