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Articles 121 - 150 of 159
Full-Text Articles in Terrestrial and Aquatic Ecology
The Tadpole Of Phrynobatrachus Mababiensis Fitzsimons, 1932 (Anura, Ranidae, Petropedetinae), Rafael O. De Sá, Alan Channing
The Tadpole Of Phrynobatrachus Mababiensis Fitzsimons, 1932 (Anura, Ranidae, Petropedetinae), Rafael O. De Sá, Alan Channing
Biology Faculty Publications
The puddle frog genus Phrynobatrachus Günther, 1862 comprises about 64 currently recognized species (Frost, 1985). Of these, only the tadpoles of P. natalensis (Smith, 1849) (Power, 1927; Channing, 2001), P. guineensis Guibé & Lamotte, 1961(Rödel,1998) and P. alticola Guibé & Lamotte, 1961 (Rödel & Ernst, 2002) have been described. Phrynobatrachus mababiensis FitzSimons, 1932 (Dwarf Puddle frog, Wager, 1986; Mababe River frog, Frank & Ramus, 1996) is a small frog that usually calls from low in thick vegetation on flooded terrains close to the water. Very little has been published about the biology of this species. Passmore & Carruthers (1979) reported …
Leptodactylus Mystacinus, M. M. Heyer, W. R. Heyer, Rafael O. De Sá
Leptodactylus Mystacinus, M. M. Heyer, W. R. Heyer, Rafael O. De Sá
Biology Faculty Publications
Adult Leptodactylus mystacinus are of moderate size, the head is as wide as long, and the hind limbs are moderately short (see Table; Heyer and Thompson 2000 provided definitions of adult size and leg length categories for Leptodactylus). Male vocal sacs are not visible externally or at best are weakly expanded laterally and slightly darker than female throats. Male snouts are more spatulate than those of females. Male forearms are not hypertrophied. Males lack asperities on the thumbs and chest. One or two pairs of dorsolateral folds (indicated by dark/light outlining in indifferently preserved specimens) are present: one …
Relationship Between Habitat Area And The Distribution Of Tidal Marsh Birds, Lori K. Benoit, Robert A. Askins
Relationship Between Habitat Area And The Distribution Of Tidal Marsh Birds, Lori K. Benoit, Robert A. Askins
Biology Faculty Publications
To assess the relationship between marsh area and relative abundance of tidal marsh bird species, we surveyed birds on 86 circular plots in 40 salt and brackish tidal marshes in Connecticut. We measured marsh area in two ways: the amount of contiguous marsh vegetation not interrupted by broad barriers (>500 m of open water or >50 m of upland habitat) and by narrow barriers (>30 m of open water or >10 m upland). We determined the relationship between marsh area and the relative abundance of particular species (mean number of individuals per survey plot) with linear or logistic …
The Tadpole Of Proceratophrys Avelinoi (Anura: Leptodactylidae), Rafael O. De Sá, José A. Langone
The Tadpole Of Proceratophrys Avelinoi (Anura: Leptodactylidae), Rafael O. De Sá, José A. Langone
Biology Faculty Publications
The genus Proceratoprhys is poorly known. It consists of 14 currently recognized species (Frost, 2000) of medium-sized frogs distributed from northeastern Argentina and Paraguay to southeast Amazonia (Rondonia State), eastern and southern Brazil Proceratophrys avelinoi was described from Misiones, Argentina (Mercadal de Barrio and Barrio, 1993). The larval stage of this species is unknown. Herein, we describe the tadpole and the characteristics of the internal oral anatomy of P. avelinoi using scanning electron microscopy (SEM).
The Tadpole Of Proceratophrys Avelinoi (Anura: Leptodactylidae), Rafael O. De Sá, José A. Langone
The Tadpole Of Proceratophrys Avelinoi (Anura: Leptodactylidae), Rafael O. De Sá, José A. Langone
Biology Faculty Publications
The genus Proceratoprhrys is poorly known. It consists of 14 currently recognized species (Frost, 2000) of medium-sized frogs distributed from northeastern Argentina and Paraguay to southeast Amazonia (Rondonia State), eastern and southern Brazil. Proceratophrys avelinoi was described from Misiones, Argentina (Mercadal de Barrio and Barrio, 1993). The larval stage of this species is unknown. Herein, we describe the tadpole and the characteristics of the internal oral anatomy of P avelinoi using scanning electron micros- copy (SEM).
Helping Shrubland Birds, Robert A. Askins
Helping Shrubland Birds, Robert A. Askins
Biology Faculty Publications
Dr. Askins argues that shrublands were part of the pre-Colonial landscape in Connecticut, so it's logical to create forest openings to help shrubland birds.
Leptodactylus Silvanimbus, W. R. Heyer, Rafael O. De Sá, Sarah Muller
Leptodactylus Silvanimbus, W. R. Heyer, Rafael O. De Sá, Sarah Muller
Biology Faculty Publications
Adult Leptodactylus silvanimhus are of moderate sized, the head is about as wide as long, and the hind limbs are moderate in length (see Table; also see Heyer and Thompson 2000 for definitions of adult size and leg length categories for Leptodacrylus). The male vocal sac is single and internal. Male forearms are hypertrophied in larger individuals. Adult males have two black thumb spines on each hand and lack chest spines. Individuals lack dorsolateral folds. The toe tips are narrow, not expanded. Females have weakly developed lateral toe fringes and males either have lateral toe ridges or weakly developed fringes. …
Sustaining Biological Diversity In Early Successional Communities: The Challenge Of Managing Unpopular Habitats, Robert A. Askins
Sustaining Biological Diversity In Early Successional Communities: The Challenge Of Managing Unpopular Habitats, Robert A. Askins
Biology Faculty Publications
No abstract provided.
A Common Pattern Of Somite Cell Rotation In Three Species Of Pipidae, Shou-Yuan Fan, Rafael O. De Sá, Gary P. Radice
A Common Pattern Of Somite Cell Rotation In Three Species Of Pipidae, Shou-Yuan Fan, Rafael O. De Sá, Gary P. Radice
Biology Faculty Publications
During amphibian somitogenesis, presumptive myotome cells change shape from round or polygonal to elongated and aligned parallel to the notochord (for reviews see Radice, et al., 1989; Keller, 2000). Although the final orientation of myotomal cells is always axial, the movements that achieve this final arrangement can differ greatly between species. The simplest movement is that seen in Bombina variegata, Pelobates fuscus, and Bufo bufo (Brustis et al., 1976; Brustis, 1979; Kielbowna, 1981 ). In these anurans, after segmentation myotomal cells simply elongate along the embryo’s anteroposterior axis. The urodeles Ambystoma mexicanum and Pleurodeles waltl have a very different pattern; …
Do Timing And Pattern Of Myogenesis Correlate With Life History Mode In Anurans?, Matthew T. Smetanick, Rafael O. De Sá, Gary P. Radice
Do Timing And Pattern Of Myogenesis Correlate With Life History Mode In Anurans?, Matthew T. Smetanick, Rafael O. De Sá, Gary P. Radice
Biology Faculty Publications
The timing and pattern of myogensis varies among anurans that have been studied and the different patterns may provide useful phylogenetic information. Specific myogenic markers have been described (Muntz, 1975; Kielbowna, 1981; Boudjelida & Muntz, 1987; Radice et al., l989) and they can provide information on evolutionary changes for closely related lineages within a clade. For example, we previously compared first appearance of a muscle-specific protein, first twitch of axial muscle, onset of multinucleation within axial myotome, and first heartbeat in two pipid genera (Smetanick, et al., 1999). We found that although the timing of myogensis differed, the sequence of …
Parental Care In Sphaerium Striatinum Lamarck: Evidence For Retention Of Competent Offspring, Mark Beekey, Ronald H. Karlson, Alyse R. Greenberg
Parental Care In Sphaerium Striatinum Lamarck: Evidence For Retention Of Competent Offspring, Mark Beekey, Ronald H. Karlson, Alyse R. Greenberg
Biology Faculty Publications
The timing of offspring release is a fundamental turning point in the life history of any organism. It represents the end to many of the most costly forms of parental care (e.g., provisioning of nutrients for developing eggs and zygotes) and the beginning of an independent life for the offspring. Generally temporal variation in this event is attributed to a variety of physiological and evolutionary trade-offs. Here we examine the retention of offspring in the freshwater clam Sphaerium striatinum Lamarck. Brooded offspring are typically not released into the environment until they are 4.0 mm shell length (SL). We provide evidence …
Los Anfibios Del Monumento Natural Barro Colorado, Parque Nacional Soberania Y Areas Adyacentes, Rafael O. De Sá
Los Anfibios Del Monumento Natural Barro Colorado, Parque Nacional Soberania Y Areas Adyacentes, Rafael O. De Sá
Biology Faculty Publications
This book focuses on the batrachofauna of Barro Colorado Nature Monument. Soberania National Park and adjacent areas. It complements other recent publications on Neotropical amphibians such as those by Rodriguez and Duellman ( 1994) on Peru, Achaval and Olmos (1995) on Uruguay, and Meyer and Foster (1996) on Belize. The goal of these books is to reach a wider audience than the more technical batrachofaunal summaries-e.g., Frogs of Boracéia (Heyer 1990). Amphibians of Argentina (Cei 1985), and Frogs of the Genus Eleutherodactylus in Western Ecuador (Lynch and Duellman 1997). These geographically focused guides are especially useful to students, amateur biologists, …
Los Coquís De Puerto Rico: Su Historia Natural Y Conservación, Rafael O. De Sá
Los Coquís De Puerto Rico: Su Historia Natural Y Conservación, Rafael O. De Sá
Biology Faculty Publications
As the title indicates, this well-illustrated (115 photographs and 76 illustrations) book summarizes the current knowledge about the natural history of the 16 species of Eleutherodactylus inhabiting Puerto Rico. The book consists of eight chapters (including the epilogue) and it is clearly stated that it was written to serve both the scientific community and the nonspecialist reader. The goal of bridging these two audiences is ambitious and usually difficult; however, the book has probably accomplished this goal. The technical reader, i.e., students and professional herpetologists, will find a good summary of data and enough information to continue reading with interest. …
Differences In Bird Communities On The Forest Edge And In The Forest Interior: Are There Forest-Interior Specialists In Japan?, Reiko Kurosawa, Robert A. Askins
Differences In Bird Communities On The Forest Edge And In The Forest Interior: Are There Forest-Interior Specialists In Japan?, Reiko Kurosawa, Robert A. Askins
Biology Faculty Publications
Most North American bird species that are less successful in small forests than in large forests, are forest-interior specialists that winter in the tropics. These species have declined in small forests because of high rates of nest predation and brood parasitism near the forest edge. To determine whether migratory forest-interior specialists are also important components of bird communities in Japan, we surveyed bird populations on plots at the edge and in the interior of deciduous forests in Hokkaido and Kyoto. Surveys were conducted during the breeding season in forest fragments using the point count method. We calculated edge indices for …
History Of Grassland Birds In Eastern North America, Robert A. Askins
History Of Grassland Birds In Eastern North America, Robert A. Askins
Biology Faculty Publications
Until recently the severe decline in the populations of many species of grassland birds in eastern North America has aroused relatively little concern or conservation action. This response appears to be rooted in the perception that grassland birds invaded the East Coast from western grasslands after European settlers cleared the forest. Detailed historical accounts and analysis of pollen deposits, however, show that open grasslands existed on the East Coast of North America at the time of European settlement. Extensive grasslands resulted from burning and agricultural clearing by Native Americans. Natural disturbances, such as wildfire and beaver (Castor canadensis) activity, produced …
Comparing The Tadpoles Of Hyla Geographica And Hyla Semilineata, Anne D'Heursel, Rafael O. De Sá
Comparing The Tadpoles Of Hyla Geographica And Hyla Semilineata, Anne D'Heursel, Rafael O. De Sá
Biology Faculty Publications
External morphology, internal oral anatomy, and chondrocranial anatomy were examined for tadpoles of Hyla geographica from the Amazon rainforest, Brazil, and Hyla semilineata from the Atlantic rainforest, Brazil. Here, we provide morphological larval data to help diagnose these closely related species. Scanning electron microscopy analysis of buccal morphology showed the most distinctive features between these species: the distance between the lingual papillae in the buccal floor of H. geographica is three times greater than that distance in H. semilineata, and the relative size of the lingual papillae in H. geographica is less than half their size in H. semilineata. Although …
Estructura Del Condrocráneo Y Esqueleto Visceral De Larvas De Pseudis Minuta (Anura, Pseudidae, E. O. Lavilla, Rafael O. De Sá
Estructura Del Condrocráneo Y Esqueleto Visceral De Larvas De Pseudis Minuta (Anura, Pseudidae, E. O. Lavilla, Rafael O. De Sá
Biology Faculty Publications
The chondrocranium and visceral skeleton of Pseudis minuta tadpoles are described, based on a series of five larvae in stages 31 - 35 of Gosner (1960). Among their striking characters are the presence of peculiar articular surfaces between cornua trabeculae and suprarostral cartilage, the incomplete development of the orbital cartilage, the high fenestration of the floor of the cavum cranii, the fusion of posterior foramina, and the fusion of spicules 3 and 4 in the hyobranchial skeleton.
The Timing And Pattern Of Myogenesis In Hymenochirus Boettgeri, Matthew T. Smetanick, Rafael O. De Sá, Gary P. Radice
The Timing And Pattern Of Myogenesis In Hymenochirus Boettgeri, Matthew T. Smetanick, Rafael O. De Sá, Gary P. Radice
Biology Faculty Publications
Differences in the relative timing of homologous developmental events among closely related species, known as heterochronies, may provide valuable clues in understanding evolutionary relationships (McKinney, 1988; McNamara, 1995). Examining the timing of myogenic events is a relatively easy and effective method for finding heterochronic events. For example, whether muscle proteins and myofibrils appear before or after multinucleation can be determined through histological techniciques (Kielbowna, 1981). Simple observations of live specimens can pinpoint functional landmarks such as first twitch (spontaneous or due to external stimuli) and first heartbeat.
Development Of The Suprarostral Plate Of Pipoid Frogs, Rafael O. De Sá, Charles C. Swart
Development Of The Suprarostral Plate Of Pipoid Frogs, Rafael O. De Sá, Charles C. Swart
Biology Faculty Publications
The rostral region of nonpipoid tadpoles has two sets of cartilages, the cornua trabeculae and the suprarostral cartilages, whereas the rostral region in pipoid larvae is occupied by a single and continuous cartilage, the suprarostral plate. The homology of this region in pipoid and nonpipoids tadpoles has been controversial. We examined the early formation and development of the suprarostral plate using serially cross-sectioned specimens of Rhinophrynus, Xenopus, and Hymenochirus. We conclude that the cartilaginous structures present in the rostral area of pipoid and nonpipoid larvae are homologous. Furthermore, we found two different developmental patterns among pipoid larvae. The chondrocranium …
Osteological Analysis Of The Killifish Genus Cynolebias (Cyprinodontiformes: Rivulidae), Marcelo Loureiro, Rafael O. De Sá
Osteological Analysis Of The Killifish Genus Cynolebias (Cyprinodontiformes: Rivulidae), Marcelo Loureiro, Rafael O. De Sá
Biology Faculty Publications
Relationships among the species of the annual fish Cynolebias are unclear. An analysis of the variation and utility of osteological characters for phylogenetic analysis was done using cleared and double-stained specimens representing 21 species of Cynolebias. This analysis showed that some of the characters previously used to diagnose this genus and some of the species are polymorphic. Osteologically, Cynolebias can be diagnosed by the following synapomorphies: (1) triangular-shaped parietal, (2) vomer positioned ventral to the parasphenoid, (3) long ventral process of the dentary, (4) teeth on fourth ceratobranchial, and (5) teeth on first epibranchial. In addition, characters that help …
Unidad De Los Anfibios Modernos Como Grupo Natural, Rafael O. De Sá
Unidad De Los Anfibios Modernos Como Grupo Natural, Rafael O. De Sá
Biology Faculty Publications
RESUMEN
La monofilia de la infraclase Lissamphibia ha sido cuestionada. Algunos autores sugieren un origen independiente del Orden Gymnophiona basados en la condición compacta (= estegocrotafía) del cráneo de la cecilias. La presente revisión indica la irrelevancia del estegocrotafismo para establecer las relaciones filogenéticas del grupo. Los datos disponibles sugieren: 1) el estegocrotafismo es secundariamente derivado en cecilias, y 2) Lissamphibia representa un grupo monofilético.
SUMMARY
Unity of modern Amphibians as a natural group
The monophyly of Lissamphibia has been previously questioned. Some authors suggested an independent origin of Gymnophiona based on the solid condition (= stegokrotaphy) of the caecilian …
Reproductive Success Of Ospreys At Two Sites In Connecticut, Donna Christine O'Neill, Robert A. Askins
Reproductive Success Of Ospreys At Two Sites In Connecticut, Donna Christine O'Neill, Robert A. Askins
Biology Faculty Publications
Nest success rates and rates of fish delivery to nests were determined for two large Osprey populations in COlmecticut, one at Groton Reservoir, Groton, and one at Great Island, Old Lyme, during 1996 and 1997. Between 1993 and 1996 these Osprey populations had substantially different rates of nest success. Great Island Ospreys fledged few young while Groton Reservoir Ospreys had good nest success. During 1997, however, fledging rates were similar at the two sites. In 1996, low nest success at Great Island 'resuited from high predation rates, probably due to raccoons. The higher nest success rate at this site in …
Chondrocranial Anatomy And Skeletogenesis In Dendrobates Auratus, Rafael O. De Sá, Shannon Hill
Chondrocranial Anatomy And Skeletogenesis In Dendrobates Auratus, Rafael O. De Sá, Shannon Hill
Biology Faculty Publications
The larval chondrocranium and visceral skeleton of Dendrobates auratus ls described and compared with those of other dendrobatids. Four characters, i.e. lack of fusion between orbital cartilages and otic capsules, wide processus muscularis palatoquadrati, lack of processus pseudopterygoideus, and lack of processus anterolateralis hyalis, represent derived conditions for Dendrobates within Dendrobatidae. Cranial and postcranial ossification sequences are reported for D. auratus and Epipedobates tricolor. Skeletogenesis is earlier in E. tricolor, but the overall pattern of ossification is similar in the two species.
Description Of The Tadpole Of Atelopus Tricolor, E. O. Lavilla, Rafael O. De Sá, Ignacio De La Riva
Description Of The Tadpole Of Atelopus Tricolor, E. O. Lavilla, Rafael O. De Sá, Ignacio De La Riva
Biology Faculty Publications
Tadpoles of Atelopus belong to the gastromyzophorous guild of exotrophic larvae (Altig and Johnston, 1989), and are characterized by the presence of a conspicuous abdominal sucker and an expanded oral disc. The larvae of several Atelopus species have been described previously: A. varius (Starrett, 1967); A. certus, A. ignescens, and A. spumarius (Duellman and Lynch, 1969); A. cruciger (Mebs, 1980); A. flavescens (Lescure, 1981); A. peruensis (Gray and Cannatella, 1985); and A. subornatus (Lynch, 1986). These represent about 15% of the known species in the genus (Frost, 1985; Duellman, 1993). Although Atelopus tricolor was originally described at the beginning of …
Leptodactylus Silvanimbus (Amphibia: Anura: Leptodactylidae): Natural History Notes, Advertisement Call, And Relationships, W. Ronald Heyer, Rafael O. De Sá, James R. Mccranie, Larry David Wilson
Leptodactylus Silvanimbus (Amphibia: Anura: Leptodactylidae): Natural History Notes, Advertisement Call, And Relationships, W. Ronald Heyer, Rafael O. De Sá, James R. Mccranie, Larry David Wilson
Biology Faculty Publications
In July 1995, we visited two of the three previously known localities for Leprodactylus silvanimbus in Departamento de Ocotepeque, Honduras. We found a new breeding site for the species, recorded its advertisement call, and collected and observed its adults and larvae. The purpose of this paper is to present the results of these new findings and to comment on the relationships L. silvanimbus.
Características De La Osificación Craneal En Phyllomedusa Boliviana (Anura: Hylidae), Rafael O. De Sá, E. O. Lavilla
Características De La Osificación Craneal En Phyllomedusa Boliviana (Anura: Hylidae), Rafael O. De Sá, E. O. Lavilla
Biology Faculty Publications
RESUMEN. Dentro de la familia Hylidae disponemos de información sobre las secuencias de osificación craneal para menos del 4.0% de sus miembros. El presente trabajo describe la secuencia de osificación craneal de Phyllomedusa boliviana. El patrón general de osificación es similar a lo reportado para otras especies de la familia, pero existen algunas diferencias importantes tales como la osificación tardía de los próoticos y la osificación premetamórfica de neopalatino, vómer, cuadrado-yugal, pterigoides y columela. El lento desarrollo ulterior de la osificación resulta en juveniles con cráneos extensamente cartilaginosos.
ABSTRACT. Characteristics of the cranial ossification in Phyllomedusa …
Conservation Of Grassland Birds In The Northeast, Robert A. Askins
Conservation Of Grassland Birds In The Northeast, Robert A. Askins
Biology Faculty Publications
No abstract provided.
Open Corridors In A Heavily Forested Landscape: Impact On Shrubland And Forest-Interior Birds, Robert A. Askins
Open Corridors In A Heavily Forested Landscape: Impact On Shrubland And Forest-Interior Birds, Robert A. Askins
Biology Faculty Publications
In eastern North America, remnant patches of forest surrounded by open habitat constitute unfavorable habitat for many species of migratory forest birds because of high rates of nest predation and cowbird parasitism. Although most evidence for this relationship comes from 'forest islands' surrounded by residential or agricultural land, even forest patches isolated from other forests by narrow open corridors such as roads and powerline rights-of-way seem to show this pattern. Productive habitat for migratory birds can be maintained by consolidating corridors and routing them along the periphery of forests to retain as much continuous forest as possible. Consolidation of open …
Terrapene Carolina Carolina, Joseph C. Mitchell, Rafael O. De Sá
Terrapene Carolina Carolina, Joseph C. Mitchell, Rafael O. De Sá
Biology Faculty Publications
TERRAPENE CAROLINA CAROLINA (Eastern Box Turtle). REPRODUCTION. Female Terrapene carolina containing oviductal eggs have been recorded in Virginia from 26 May to 25 July (Mitchell, in press. The Reptiles of Virginia. Smithsonian Inst. Press, Washington, D.C.). Other reports of reproduction in Terrapene (see list in Ernst and McBreen 1991. Cat. Amer. Amphib. Rept. 512.1-512.13) indicate that nesting occurs in late spring and early summer throughout its range.
Population Studies Of Migratory Birds In Virgin Islands National Park, Robert A. Askins, David N. Ewert
Population Studies Of Migratory Birds In Virgin Islands National Park, Robert A. Askins, David N. Ewert
Biology Faculty Publications
The majority of the individual songbirds nesting in the deciduous forests of eastern North America migrate to the West Indies, Central America and South America during the winter. They typically spend more than six months in tropical winter habitats. Until recently relatively little was known about their habitat requirements during the winter, but increasing concern about declining pcpulations of many migratory songbirds combined with widespread alarm about the rapid destruction of tropical forests has led to a flurry of research on this subject (Terborgh, 1989; Askins et al. 1990). In 1987 we initiated a study of the ecology and behavior …