Elizabeth Höfling

Systematic revision of the Phorusrhacidae (Aves: Ralliformes)

Foram estudados os fosseis de aves atribuidos a familia Phorusrhacidae depositados em diversos museus da America do Sul, da America do Norte e da Europa, com o objetivo principal de caracterizar esta familia e reorganizar o estado caotico que ate entao envolvia a nomenclatura e classificacao destas aves. A reconstituicao de algumas especies e feita, com o proposito de formar uma ideia sobre o tamanho, massa corporea, postura e habitos com base no esqueleto das mesmas. As formas europeias, Ameghinornis minor e Aenigmavis sapea sao refutadas como pertencentes a esta familia. Sao refutadas ainda varias formas do Terciario da Argentina, descritas com base em segmentos de esqueleto, insuficientes para uma plena identificacao como e o caso dos generos Cunampaia, Smiliornis, Pseudolarus, Lophiornis e Riacama, frequentemente referidos como pertencentes aos Phorusrhacidae. A familia Phorusrhacidae certamente originou-se na America do Sul pelo final do Cretaceo, como resultado de um endemismo formado pelo isolamento dessa porcao de terra. Pelo final do Plioceno, com a emersao do istmo do Panama, a familia estendeu-se ate a America do Norte onde pelo menos uma especie, Titanis walleri que talvez represente a ultima conhecida desta familia, que extinguiu-se no inicio do Pleistoceno. A revisao sistematica foi conduzida com inumeros problemas de nomenclatura e a familia Phorusrhacidae passa entao a ser constituida de cinco subfamilias, ou seja: Brontornithinae, Phorusrhacinae, Patagornithinae, Psilopterinae e Mesembriornithinae, nas quais se distribuem 13 generos e 17 especies. Os caracteres de todos os taxons sao descritos e finalmente e apresentada uma distribuicao geocronologica de todas as especies.

Osteology of the Shoulder Girdle in the Piciformes, Passeriformes and Related Groups of Birds

Abstract A comparative study of the bones of the shoulder girdle in the Piciformes, Passeriformes and Coraciiformes, and also in related orders of birds such as the Trogoniformes, Coliiformes, Apodiformes, Strigiformes and Caprimulgiformes, is presented and discussed. A number of observed characters justify inclusion only the families Indicatoridae, Picidae, Capitonidae and Ramphastidae in the order Piciformes, while also demonstrating a close resemblance with the Passeriformes that suggests a monophyletic origin for these two orders. On the other hand, although the closely related Bucconidae and Galbulidae are not included in the Piciformes they more closely resemble the Coraciiformes, particularly the Meropidae, Coraciidae and Brachypteraciidae. Among the Coraciiformes, it was observed that the Upupidae closely resemble the Phoeniculidae and, to a lesser extent, the Bucerotidae (particularly Tockus ). For other coraciiforms, observation of shoulder girdle osteology alone did not provide sufficient evidence to justify a family grouping or a clearer definition of the boundaries of this order.

The legs: a key to bird evolutionary success

Birds are the most diverse and largest group of extant tetrapods. They show marked variability, yet much of this variation is superficial and due to feather and bill color and shape. Under the feathers, the skeleto-muscular system is rather constant throughout the bird group. The adaptation to flight is the explanation for this uniformity. The more obvious morphological adaptations for flight are the wings, but the trunk is always rigid, the tail is short and the neck is flexible, since all these features are correlated with flying behaviour. Unrelated to the exigencies of flight, the legs always have three long bones, and all the birds walk on their toes. This leg structure is a striking plesiomorphic feature that was already present in related dinosaurs. The multi-purpose potential of the legs is the result of the skeletal architecture of a body with three segmented flexed legs. This configuration provides mechanical properties that allow the use of the legs as propulsive, paddling, foraging or grooming tools. It is the association of diverse modes of locomotion—walking, running, hopping, flying and swimming—that have enabled the birds to colonize almost all the environments on Earth.

Description of a New Species of Pionopsitta (Aves: Psittacidae) Endemic to Brazil

Abstract A new species from Brazil—Pionopsitta aurantiocephala—is described, which is easily distinguished from the other species of that genus by its completely bare, intensely orange colored head. Specimens of this species have been historically identified as immatures of P. vulturina, which occur in simpatry with P. aurantiocephala on the Middle Tapajós River and possibly on the Lower Madeira River. The description of a new species of Psittacidae stresses the importance of new studies in the regions of the Madeira and Tapajós rivers.

A NEW SPECIES OF ARATINGA PARAKEET (PSITTACIFORMES: PSITTACIDAE) FROM BRAZIL, WITH TAXONOMIC REMARKS ON THE ARATINGA SOLSTITIALIS COMPLEX

Abstract We describe a new species of Aratinga—A. pintoi (Sulfur-breasted Parakeet)—from open areas on the northern bank of the lower Amazon River in the state of Pará, Brazil. It was for a long time misidentified as a juvenile of A. solstitialis or a hybrid between that species and A. jandaya. It can be distinguished from other Aratinga species by the combination of the following characters: mantle and wing coverts green, suffused with pale yellow; underparts pale yellow, with pale orange restricted to belly and flanks; and feathers on the underparts with a dark rachis. On the basis of color characters and general morphology, we suggest that this new species should be a member of a group composed of A. solstitialis, A. jandaya, A. auricapillus, and, possibly, Nandayus nenday. A review of taxonomy and distribution of the group is also presented. Uma nova espécie de Aratinga (Psittaciformes: Psittacidae) do Brasil, com comentários sobre a taxonomia do complexo de espécies Aratinga solstitialis

Osteologia craniana de Coraciiformes (Aves)

The families Alcedinidae (kingfishers), Momotidae (motmots), Todidae (todies), Meropidae (bee-eaters), Coraciidae (rollers), Brachypteraciidae (ground-rollers), Leptosomidae (cuckoo-rollers), Phoeniculidae (woodhoopoes), Upupidae (hoopoes) and Bucerotidae (hornbills) are traditionally grouped in the Order Coraciiformes, but no external morphological character is commom to the whole order. A comparative study of the cranial osteology of the Coraciiformes seeks to find characters capable to diagnose the order or groups of taxa, serving yet as a source to provide characters for future phylogenetic analysis. As established by the external morphological data, the cranial osteology has ratified the broad morphological divergence among the Coraciiformes taxa. Only two characters are common to the Order as a whole, as the presence of the laterosphenoid fossa and the absence of the suprameatic process, but these characters are not exclusive of the order. Primary homologies were found, showing similarities among several families, such as: the craniofacial flexion zone is an indefinite region in adults of the Coraciidae, Leptosomidae, Phoeniculidae, Upupidae and Bucerotidae; the temporal fossa has intermediate development and deepy in the Momotidae, Meropidae, Coraciidae, Brachypteraciidae and Bucerotidae; the lacrimal bone is absent in the Momotidae, fused with the ectethmoid in adults of the Upupidae, Phoeniculidae and Bucerotidae, and present and free in the Alcedinidae, Todidae, Meropidae, Coraciidae, Brachypteraciidae and Leptosomidae; and the o retroarticular process of the mandible is developed in the Upupidae, Phoeniculidae and Bucerotidae.

Locomotion patterns in two South American gymnophthalmid lizards: Vanzosaura rubricauda and Procellosaurinus tetradactylus

We quantified gait and stride characteristics (velocity, frequency, stride length, stance and swing duration, and duty factor) in the bursts of locomotion of two small, intermittently moving, closely related South American gymnophthalmid lizards: Vanzosaura rubricauda and Procellosaurinus tetradactylus. They occur in different environments: V. rubricauda is widely distributed in open areas with various habitats and substrates, while P. tetradactylus is endemic to dunes in the semi-arid Brazilian Caatinga. Both use trot or walking trot characterised by a lateral sequence. For various substrates in a gradient of roughness (perspex, cardboard, sand, gravel), both species have low relative velocities in comparison with those reported for larger continuously moving lizards. To generate velocity, these animals increase stride frequency but decrease relative stride length. For these parameters, P. tetradactylus showed lower values than V. rubricauda. In their relative range of velocities, no significant differences in stride length and frequency were recorded for gravel. However, the slopes of a correlation between velocity and its components were lower in P. tetradactylus on cardboard, whereas on sand this was only observed for velocity and stride length. The data showed that the difference in rhythmic parameters between both species increased with the smoothness of the substrates. Moreover, P. tetradactylus shows a highly specialised locomotor strategy involving lower stride length and frequency for generating lower velocities than in V. rubricauda. This suggests the evolution of a central motor pattern generator to control slower limb movements and to produce fewer and longer pauses in intermittent locomotion.

Foot shape in arboreal birds: two morphological patterns for the same pincer-like tool

The feet are the only contact between the body and the substrate in limbed animals and as such they provide a crucial interface between the animal and its environment. This is especially true for bipedal and arboreal species living in a complex three‐dimensional environment that likely induces strong selection on foot morphology. In birds, foot morphology is highly variable, with different orientations of the toes, making it a good model for the study of the role of functional, developmental, and phylogenetic constraints in the evolution of phenotypic diversity. Our data on the proportions of the phalanges analyzed in a phylogenetic context show that two different morphological patterns exist that depend mainly on habitat and toe orientation. In the anisodactyl foot, the hallux is the only backward‐oriented toe and is enlarged in climbing species and reduced in terrestrial ones. Moreover, a proximo‐distal gradient in phalanx size is observed depending on the degree of terrestriality. In the two other cases (heterodactyl and zygodactyl) that have two toes that point backward, the hallux is rather small in contrast to the other backward‐pointing toe, which is enlarged. The first pattern is convergent and common among tetrapods and follows rules of skeletal development. The second pattern is unique for the clade and under muscle–morphogenetic control. In all cases, the functional result is the same tool, a pincer‐like foot.

Relationship Between Jaw Apparatus, Feeding Habit, and Food Source in Oriental Woodpeckers

Associations among feeding habit, beak type, and food source in birds have been widely studied and are well known to exist. The relationship between feeding habit and jaw apparatus in birds has not attracted attention from ornithologists, perhaps because of the complexity of the skeletal morphology of the feeding system of birds. The goal of this study was to compare the jaw apparatus and foraging strategies of various Oriental species of the Picidae (Meiglyptini and Picini tribes) using a morphofunctional analysis of the skeletal structure of the jaw apparatus. This study showed that there are at least three types of jaw apparatus in these woodpeckers, as follows: 1) robust, developed, and complex; 2) complexity and development intermediate, as observed in Meiglyptes tristis and Dinopium spp., whose main foraging method involves gleaning, probing, and tapping; and 3) poorly developed, as observed in Picus miniaceus and Hemicircus concretus. The success of woodpeckers as a natural group is due not only to their feeding diversity, but also their ability to explore a wide range of different resources, as appropriate to their jaw apparatus.

Effects of Surface Roughness on the Locomotion of a Long-Tailed Lizard, Colobodactylus taunayi Amaral, 1933 (Gymnophthalmidae: Heterodactylini)

We analyzed the locomotor behavior of a long-tailed, forest floor, and leaf litter lizard, Colobodactylus taunayi, a species that retains the generalized Gymnophthalmidae Bauplan whilst presenting the discrete toe reduction associated with the Bachia-like pattern of limb reduction. We videotaped individuals moving on four substrates with increasing degrees of roughness: plastic, wooden board, glued sand, and glued gravel. Significantly higher speeds occurred on the last two substrates. As with most other limbed animals, increased speed was significantly correlated with simultaneous increases in both stride length and stride frequency. Independently of the kind of substrate, C. taunayi used rather slow lateral sequence walking trots. In contrast to other ectothermic tetrapods, and especially other Gymnophthalmidae, this species lacked perceptible lateral flexion of either the trunk or the tail to effectuate these slow gaits.