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Full-Text Articles in Life Sciences

Designation Of A Neotype For Leptodactylus Gracilis (Duméril And Bibron, 1840) (Amphibia: Leptodactylidae), Rafael O. De Sá, A. Dubois, A. Ohler Dec 2007

Designation Of A Neotype For Leptodactylus Gracilis (Duméril And Bibron, 1840) (Amphibia: Leptodactylidae), Rafael O. De Sá, A. Dubois, A. Ohler

Biology Faculty Publications

The examination of the preserved specimens in the herpetological collection of the Museum National d'Histoire Naturelle, along with a review of the original literature, indicates that no extant specimen can be undoubtedly identified as the holotype of Leptodactylus gracilis (DumCri.l and Bibron, 1840). Furthermore, it revealed that the type locality recently assigned to this taxon is in error.


Vascular Flora Of Powhatan County, Virginia, Michael Austin Terry, W. John Hayden Sep 2007

Vascular Flora Of Powhatan County, Virginia, Michael Austin Terry, W. John Hayden

Biology Faculty Publications

Powhatan County is a largely rural county of the Virginia piedmont currently experiencing exurban development pressure. Commercial pine forests occupy much of the land area; most natural vegetation occurs in various hardwood forests. Plant life is supported largely by soils derived from Proterozoic to Paleozoic metamorphic and igneous rocks, soils developed over Triassic basins, and riparian soils associated with the James and Appomattox Rivers. The annotated checklist is based on new collections gathered between September 2003 and August 2005, supplemented with records from regional herbaria and the Atlas of the Virginia Flora. Field work sampled at least 12 distinct community …


Description Of The Tadpole Of Leptodactylus Pustulatus Peters, 1870 (Anura: Leptodactylidae), Rafael O. De Sá, Reuber Brandão, Lorena Dall'ara Guimarães Jul 2007

Description Of The Tadpole Of Leptodactylus Pustulatus Peters, 1870 (Anura: Leptodactylidae), Rafael O. De Sá, Reuber Brandão, Lorena Dall'ara Guimarães

Biology Faculty Publications

The external morphology and oral disc of the tadpole of Leptodactylus pustulatus Peters, 1870, are described and illustrated for Gosner stage 39. The internal oral anatomy was analyzed with SEM at Gosner stage 36 whereas chondrocranial anatomy is reported for Gosner stage 35. The overall characteristics do not depart from those known for the genus Leptodactylus and they particularly agree for those of the melanonotus species group. The labial tooth row formula is 2(2)/3. Observations are presented that suggest that L. pustulatus engages in larval parental care.

Resumo

São descritas a morfologia externa e o disco oral do girino de …


The Tadpole Of Eupsophus Queulensis (Anura, Cycloramphidae), Diana R. Cárdenas-Rojas, Alberto Veloso, Rafael O. De Sá May 2007

The Tadpole Of Eupsophus Queulensis (Anura, Cycloramphidae), Diana R. Cárdenas-Rojas, Alberto Veloso, Rafael O. De Sá

Biology Faculty Publications

The genus Eupsophus is characterized by endotrophic larvae that inhabit water-filled cavities. The larvae feed from large yolk reserves during metamorphosis. The external morphology has been described for four of the ten known species and data on larval chondrocranial morphology are available only for one. We describe the extema1 morphology, oral disc and chondrocranial anatomy of the larvae of Eupsophus queulensis. The characteristics of E. queulensis tadpoles are compared with those of other Eupsophus larvae.


Atamasco Lily, Zephyranthes Atamasca, W. John Hayden May 2007

Atamasco Lily, Zephyranthes Atamasca, W. John Hayden

Biology Faculty Publications

Simple and pure, Atamasco lilies were among the first of many beautiful wildflowers to be noticed by the Jamestown colonists as they explored the tidewater region of southeastern Virginia. A perennial herb that grows from a subterranean bulb, the leaves are glossy green, linear, flat to somewhat concave, up to one half inch wide and approximately one foot in length. The species name, atamasca, is attributed to Tapehanek words meaning under grass, in reference to the location of the bulb under grass-like leaves. Overall the plant is rather grass-like. Flowers are erect to slightly inclined. As in many lilies, …


Improving Natural History Research With Image Analysis: The Relationship Between Skin Color, Sex, Size And Stage In Adult Red-Spotted Newts, Andrew K. Davis, Kristine L. Grayson May 2007

Improving Natural History Research With Image Analysis: The Relationship Between Skin Color, Sex, Size And Stage In Adult Red-Spotted Newts, Andrew K. Davis, Kristine L. Grayson

Biology Faculty Publications

Natural history researchers are increasingly using digital cameras and computer software to measure their study animals. Adult Red-spotted Newts (Notophthalmus viridescens viridescens) are known to display a range of skin colors, from brown to green, but it has not been possible to quantify this variation until the advent of image analysis technology. We used an image analysis approach to compare skin color between sexes, across a range of sizes, and between aquatic and post-breeding (emigrating to the terrestrial habitat) stage adult newts. From 232 individuals (53% male, 47% female) we documented a wide but subtle range of skin …


The Tadpole Of Leptodactylus Notoaktites Heyer, 1978 (Anura, Leptodactylidae), Rafael O. De Sá, José A. Langone, Magno V. Segalla Apr 2007

The Tadpole Of Leptodactylus Notoaktites Heyer, 1978 (Anura, Leptodactylidae), Rafael O. De Sá, José A. Langone, Magno V. Segalla

Biology Faculty Publications

The external morphology and oral disc of the tadpole of Leptodactylus notoaktites Heyer, 1978, are described and illustrated for Gosner’s stage 33. The internal oral anatomy was analyzed under SEM at Gosner’s stage 36 whereas chondrocranial anatomy is reported for Gosner’ stage 38. The morphology of this tadpole is compared with those available for other species of the L. mystaceus complex. The overall characteristics do not depart from those known for the genus Leptodactylus and they particularly agree for those of the fuscus species group. The labial tooth row formula is 2(2)/3.


Green Mulch From Invasives Offers Many Benefits, W. John Hayden Apr 2007

Green Mulch From Invasives Offers Many Benefits, W. John Hayden

Biology Faculty Publications

For the past several years, I’ve been clipping leafy branchlets of autumn olive for direct use as green mulch in my vegetable garden. In essence, I clip the shoots into segments ranging from 4 to 10 inches long, gathering the freshly chopped mulch into a wheelbarrow. I like to emphasize the youngest and leafiest stems, but since I am also interested in reducing the exotic plant’s biomass, I also clip woody stems up to a half inch in diameter. I then place the coarse mulch, leaves, young stems, and chopped woody branchlets, around my vegetable plants. I install the fresh …


Zephyr Lilies: Simple Beauty Belies Complex Biology, W. John Hayden Apr 2007

Zephyr Lilies: Simple Beauty Belies Complex Biology, W. John Hayden

Biology Faculty Publications

It is often thus, the best in art appears effortless; the most compelling science, once understood, seems obvious. But talk at length with any artist or scientist and you will learn that what appears simple is actually the culmination of a great deal of work. Zephyr, or Jamestown, lilies are like that, too. These seemingly simple flowers are merely the elegant end product of some very complex underlying biology, the details of which are imperfectly understood.


Sex Differentiation Pattern In The Annual Fish Austrolebias Charrua (Cyprinodontiformes: Rivulidae), M. J. Arezo, S. D. Alessandro, N. Papa, Rafael O. De Sá, N. Berois Apr 2007

Sex Differentiation Pattern In The Annual Fish Austrolebias Charrua (Cyprinodontiformes: Rivulidae), M. J. Arezo, S. D. Alessandro, N. Papa, Rafael O. De Sá, N. Berois

Biology Faculty Publications

Sex differentiation process, determination of sexual strategy, and gametogenesis of the annual fish Austrolebias charrua are established. Evidence of histological sex differentiation in an antero-posterior gradient was observed in pre-hatching stages. Sexual strategy corresponds to the “differentiated gonochoric” pattern. Histological analyses of adult gonads showed an asynchronous spawning mode for females and continuous spawning for males. Mature oocytes presented fluid yolk. Testis organization corresponded to a restricted spermatogonial model. Herein, we report the ultrastructural organization of the vitelline envelope and the main features of the sperm of A. charrua. Taking together these results also contribute to phylogenetic studies and …


Are Hawkmoths The Mysterious Pollinators Of The Jamestown Lily?, W. John Hayden Feb 2007

Are Hawkmoths The Mysterious Pollinators Of The Jamestown Lily?, W. John Hayden

Biology Faculty Publications

“Hawkmoth flowers are easy to predict but difficult to document,” noted botanist Verne Grant in his comprehensive review of hawkmoth pollination systems in North America (Botanical Gazette 144: 439-449. 1983). Grant included Jamestown (atamasco) lilies (among other zephyr lily species) as examples of plants that are probably hawkmoth- pollinated, but for which the actual pollination mechanism remains undocumented.


2007 Wildflower Of The Year: Atamasco Lily, Zephyranthes Atamasca, W. John Hayden Jan 2007

2007 Wildflower Of The Year: Atamasco Lily, Zephyranthes Atamasca, W. John Hayden

Biology Faculty Publications

Atamasco lily is a perennial herb that grows from a subterranean bulb. The bulb is dark, with a short neck and papery tunic formed by remnants of old leaf bases. Leaves are glossy green, linear, flat to somewhat concave, up to one half inch wide, approximately one foot in length and, overall, rather grasslike. When not in flower the plants can be easily overlooked. Flowering stems are leafless scapes that are about as long as the leaves. In crosssection the scapes are hollow. Each scape terminates in a single flower. A few papery bracts subtend the flower stalk where it …


Glow Sticks As Effective Bait For Capturing Aquatic Amphibians In Funnel Traps, Kristine L. Grayson, Andrew W. Roe Jan 2007

Glow Sticks As Effective Bait For Capturing Aquatic Amphibians In Funnel Traps, Kristine L. Grayson, Andrew W. Roe

Biology Faculty Publications

Funnel traps of various designs have been used to capture adults and larvae of aquatic amphibians (e.g., Buech and Egeland 2002; Richter 1995). Most studies use unbaited funnel traps to capture amphibians while others have used shrimp or salmon eggs (Adams et al. 1997). Light traps and light sticks are commonly used in studies of fish, particularly larvae (Doherty 1987; Marchetti et al. 2004), but have not been widely used to capture amphibians. Glow sticks have been mentioned briefly in the literature as a means to increase capture rates of aquatic amphibians (Smith and Rettig 1996), but no studies have …