Two new species of Guatteria (Annonaceae) from the Atlantic Forest of Brazil

Guatteria emarginata and G. stenocarpa, two new species from the Atlantic Forest in Espirito Santo and Bahia, Brazil, are presented here. Guatteria emarginata is characterized by narrowly obovate, verruculose leaves, densely covered with cinereous hairs on the lower side and an emarginate apex. Guatteria stenocarpa is remarkable among the Atlantic Forest species of the genus for its narrowly ellipsoid to cylindric monocarps of 22-25 mm long.

Stigmatic surface in the Vochysiaceae: reproductive and taxonomic implications

(Stigmatic surface, reproductive biology and taxonomy of the Vochysiaceae). The Vochysiaceae are Neotropical trees and shrubs, common in the savanna areas in Central Brazil (Cerrados). The family has been traditionally divided into two tribes: Erismeae, with three genera, and Vochysieae, with five genera. We investigated the stigmatic surface of six Vochysiaceae species, belonging to four genera of Vochysieae: Vochysia, Salvertia, Callisthene and Qualea. Flowers and buds at different developmental stages were collected. Morphological features were observed on fresh material and stigmatic receptivity was inferred based on esterasic activity. Pistils were fixed and embedded in paraplast and sectioned on a rotary microtome; the sections were stained before histological analysis. Stigmas of open flowers were also observed by scanning electron microscopy. Stigmas of all species were wet and showed esterasic activity at pre-anthesis and anthesis stages. Stigmatic surface was continuous with transmitting tissue of glandular nature. Vochysia and Salvertia stigmatic surfaces were formed by multicelular uniseriate hairs, and species of the remaining genera showed papillate surface. The exudate over mature stigmas in all species flowed without rupture of stigmatic Surface and pollen tubes grew down between hairs or papillae. Differences on the stigmatic surface agreed with a phylogenetic reconstruction that separated two clades and indicated that Vochysieae is not monophyletic. Stigmatic features could not be associated with pollination and breeding systems.

Cladistic analysis of the Stygninae and description of a new species of Protimesius Roewer, 1913 (Opiliones: Stygnidae)

A new species of Stygnidae is described from the state of Bahia, Brazil. Protimesius bahiensis sp. nov. can be distinguished from the remaining species of the genus by the combination of: male femur IV unarmed and cylindrical; male patella IV with a row of large dorsal acute tubercles, increasing in size distally and male tibia IV with one mesodistal tubercle; ventral plate of the penis with three pairs of distal curved setae and one pair of intermediate setae, smaller than the rest. A cladistic analysis of the subfamily is presented. Stygninae is divided in two groups of genera: (Ricstygnus, Stygnus, Sickesia), with a wide distribution and (Pickeliana (Protimesius (Phareus (Stenophareus (Auranus (Verrucastygnus, Stenostygnoides)))))), associated to the Guiana Shield, Amazon basin and Northeastern Brazil. The monophyly of Protimesius is supported by the apex of pedipalpal tibia sockets bifid (homoplastically present in Verrucastygnus and Stenostygnoides) and by the presence of scopulae with non-spatulated hairs.

Two new species of Pamphobeteus Pocock 1901 (Araneae : Mygalomorphae : Theraphosidae) from Brazil, with a new type of stridulatory organ

Two new species of Pamphobeteus Pocock 1901 are described from Brazil: Pamphobeteus crassifemur sp. nov. and Pamphobeteus grandis sp. nov.; Pamphobeteus nigricolor, formerly described from Colombia, Ecuador and Bolivia, is recorded from Brazil and its distribution in Ecuador and Bolivia is questioned. A new type of stridulatory organ is described from legs III and IV of P. crassifemur sp. nov. The structure consists of spiniform setae. Stridulation occurs when the spider moves the legs III and IV, sometimes while shedding urticating hairs.

Eriosorus areniticola (Pteridaceae), a New Species from Brazil

We describe and illustrate a new species, Eriosorus areniticola, and compare it with E. myriophyllus, the species to which it is most similar. This new species is endemic to southeastern and southern Brazil. It resembles a small form of E. myriophyllus, but differs by the absence of glandular hairs on rachises and laminar tissue, smaller leaf Size, and distinct habitat.

Mechanical analysis of infant carrying in hominoids

In all higher nonhuman primates, species survival depends upon safe carrying of infants clinging to body hair of adults. In this work, measurements of mechanical properties of ape hair (gibbon, orangutan, and gorilla) are presented, focusing on constraints for safe infant carrying. Results of hair tensile properties are shown to be species-dependent. Analysis of the mechanics of the mounting position, typical of heavier infant carrying among African apes, shows that both clinging and friction are necessary to carry heavy infants. As a consequence, a required relationship between infant weight, hair-hair friction coefficient, and body angle exists. The hair-hair friction coefficient is measured using natural ape skin samples, and dependence on load and humidity is analyzed. Numerical evaluation of the equilibrium constraint is in agreement with the knuckle-walking quadruped position of African apes. Bipedality is clearly incompatible with the usual clinging and mounting pattern of infant carrying, requiring a revision of models of hominization in relation to the divergence between apes and hominins. These results suggest that safe carrying of heavy infants justify the emergence of biped form of locomotion. Ways to test this possibility are foreseen here.