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Articles 3151 - 3180 of 3789

Full-Text Articles in Ecology and Evolutionary Biology

Ecology And Population Demography Of The Hellbender, Cryptobranchus Alleganiensis, In West Virginia, W. Jeffrey Humphries Jan 1999

Ecology And Population Demography Of The Hellbender, Cryptobranchus Alleganiensis, In West Virginia, W. Jeffrey Humphries

Theses, Dissertations and Capstones

Using mark-recapture, I studied the population demography and habitat use of the hellbender, Cryptobranchus alleganiensis, in the West Fork of the Greenbrier River, Pocahontas County, West Virginia. Eighteen nocturnal surveys were conducted between April and October, 1998, during which 29 hellbenders were implanted with permanent tags. Male to female sex ratio was 1.06:1. Hellbenders were sexually dimorphic, as females were significantly longer and heavier than males. Total lengths for all captured animals ranged from 29.5 - 56.5 cm and mass ranged from 150.0 - 905.8 g. Seasonal linear movements for 12 individuals ranged from 0.8 - 70.2 m (mean …


Feeding Niches Of Forest Salamanders: Indirect Effects Of Gypsy Moth Pesticides On Prey Selection And Potential Overlap Between Adults Of Six Species, Sandra Raimondo Jan 1999

Feeding Niches Of Forest Salamanders: Indirect Effects Of Gypsy Moth Pesticides On Prey Selection And Potential Overlap Between Adults Of Six Species, Sandra Raimondo

Theses, Dissertations and Capstones

Amphibian declines and deformities are indictors of pollution and other environmental impacts. Pesticides, such as Bacillus thuringiensis var. kurstaki (Bt), may produce non-target effects on salamanders by impacting their food supply, ultimately resulting in population declines. Salamanders were used as an assessment tool of pesticide impacts before populations decline. Diet analysis determined if Bt affected food consumption of two salamander species (Desmognathus ochrophaeus and P. cinereus). Nine plots in the Monongahela National Forest, West Virginia were used in this study. Three plots were sprayed with Bt in 1997 and 1998, three were sprayed with a gypsy moth …


Distribution Of The Sucker Family (Pisces: Catostomidae) In The Ohio River, Tara L. Rose Jan 1999

Distribution Of The Sucker Family (Pisces: Catostomidae) In The Ohio River, Tara L. Rose

Theses, Dissertations and Capstones

The family Catostomidae represents a major component of the fish fauna in the Ohio River. Because of their abundance, large biomass, and susceptibility to environmentally-induced anomalies, suckers are expected to significantly influence the Ohio River Fish Index (ORFIn), a biological index being developed by the Ohio River Valley Water Sanitation Commission (ORSANCO) for large river systems. To correctly interpret information obtained from ORFIn, the impact of suckers upon the index must be thoroughly understood, including relative importance and uneven spatial distribution of Ohio River suckers. In this study, suckers represented 7.1 percent of the total fish captured and 36.6 percent …


Ecology And Natural History Of Rana Clamitans Melanota In West Virginia, Alison M. Rogers Jan 1999

Ecology And Natural History Of Rana Clamitans Melanota In West Virginia, Alison M. Rogers

Theses, Dissertations and Capstones

Fourteen study sites were sampled with aquatic funnel traps and D-frame net sweeps in the plateau and mountain region of West Virginia to determine differences in larval period. Larval stage class abundance and larval total length and mass measurements were recorded from February to December 1997. Larval stage classes 25 and 26, the first free living stages, were absent from the plateau region from February to April, but were present in the mountain region. Pre-transformation larval stages, 40 through 44, were found from May through October, and peaked in July. Significant relationships were found with simple linear regression analysis between …


Natural History Of The Northern Spring Salamander Gyrinophilus Porphyriticus Porphyriticus At The Westvaco Wildlife And Ecosystem Research Forest In Randolph County, West Virginia, Brian A. Lindley Jan 1999

Natural History Of The Northern Spring Salamander Gyrinophilus Porphyriticus Porphyriticus At The Westvaco Wildlife And Ecosystem Research Forest In Randolph County, West Virginia, Brian A. Lindley

Theses, Dissertations and Capstones

The purpose of this thesis research was to study the natural history of the northern spring salamander Gyrinophilus p. porphyriticus in West Virginia. The objectives of this study were to determine the environmental characteristics of the habitat of Gyrinophilus p. porphyriticus, to determine its reproductive biology, and then examine non-reproductive aspects of the natural history of the species. Study sites were located at the Westvaco Wildlife and Ecosystem Research Forest (WWERF) in Randolph County, West Virginia. Four sites on three streams were divided into two 25m transects. All sites were examined once each month from August 1997 through November 1998 …


Plant Hybrid Zones And Insect Host Range Expansion, Diana Pilson Jan 1999

Plant Hybrid Zones And Insect Host Range Expansion, Diana Pilson

Diana Pilson Publications

The hybrid bridge hypothesis suggests that plant hybrids ‘‘bridge’’ the genetic gap between actual and potential host species, and that, for this reason, herbivorous insects are more likely to evolve an expanded host range in the presence of hybrids. While intuitively appealing, the hypothesis has two implicit assumptions: that phenotypic gaps between potential hosts limit host range, and that characters controlling host use are additively inherited in plant hybrids. Evaluation of these assumptions suggests that operation of the hybrid bridge hypothesis is relatively uncommon. In addition, the hypothesis has not been well integrated into existing theoretical and empirical work on …


A Comment On Friedlander’S Asterocampa (Nymphalidae, Apaturinae): Designation Of Neotypes For A. Celtis And A. Clyton, Ronald R. Gatrelle Jan 1999

A Comment On Friedlander’S Asterocampa (Nymphalidae, Apaturinae): Designation Of Neotypes For A. Celtis And A. Clyton, Ronald R. Gatrelle

The Taxonomic Report of the International Lepidoptera Survey

Friedlander’s 1986 [1987] treatment of the southeastern United States. taxa of Asterocampa is examined. Neotypes of A. celtis and A. clyton are designated from Burke County, Georgia to help stabilize the status of these taxa and aid in any future research. Asterocampa celtis is currently known to exist within at least 40 km of A. c. reinthali in Georgia. Their proximity, without integration, suggests evolutionary distance, perhaps even speciation. It is proposed that A. celtis is descended from A. c. alicia, and alicia from a Mexican refugium. Asterocampa clyton and A. …


Experimental Infections Of Muskoxen (Ovibos Moschatus) And Domestic Sheep With Umingmakstrongylus Pallikuukensis (Nematoda: Protostrongylidae): Parasite Development, Population Structure, And Pathology, Susan J. Kutz, Eric P. Hoberg, Lydden Polley Jan 1999

Experimental Infections Of Muskoxen (Ovibos Moschatus) And Domestic Sheep With Umingmakstrongylus Pallikuukensis (Nematoda: Protostrongylidae): Parasite Development, Population Structure, And Pathology, Susan J. Kutz, Eric P. Hoberg, Lydden Polley

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Three captive muskoxen (Ovibos moschatus) were successfully infected with third-stage larvae of Umingmakstrongylus pallikuukensis digested or emerged from the slugs Deroceras reticulatum and D. laeve, for the first time completing the life cycle of this parasite under experimental conditions. The course of parasite development and patency was followed for 26 months post infection (p.i.) using fecal examinations and radiography. The prepatent periods in two of the muskoxen were 91 and 95 days and the patent period in one extended for 23 months. Larval production peaked 13–14 months p.i. On postmortem of two of the muskoxen at months …


The Chondrocranium Of The Mexican Burrowing Toad, Rhinophrynus Dorsalis, Charles C. Swart, Rafael O. De Sá Jan 1999

The Chondrocranium Of The Mexican Burrowing Toad, Rhinophrynus Dorsalis, Charles C. Swart, Rafael O. De Sá

Biology Faculty Publications

The chondrocranium of Rhinophrynus dorsalis is described and illustrated. Autapomorphies of R. dorsalis are the presence of the symplectic cartilage and a cartilaginous process on the ascending process of the palatoquadrate. Synapomorphies of Rhinophrynus shared with the Pipidae are: (1) early formation of the lower jaw and (2) presence of a suprarostral plate. Alternative developmental pathways for the formation of the suprarostral plate are considered. Histological data indicates that the suprarostral plate forms from: (1) the early fusion of the cornua trabeculae with the suprarostral cartilages, (2) an anterior growth of the ethmold plate, and (3) subsequent fusion …


Unidad De Los Anfibios Modernos Como Grupo Natural, Rafael O. De Sá Jan 1999

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 …


Subspecific Status Of Southeastern U.S. Megathymus Cofaqui And M. Yuccae: Renaming Of The Florida Subspecies Of M. Cofaqui, Ronald R. Gatrele Jan 1999

Subspecific Status Of Southeastern U.S. Megathymus Cofaqui And M. Yuccae: Renaming Of The Florida Subspecies Of M. Cofaqui, Ronald R. Gatrele

The Taxonomic Report of the International Lepidoptera Survey

Megathymus cofaqui and M. yuccae are both represented in the southeastern United States by two subspecies. The type locality of both M. y. yuccae and M. c. cofaqui is the area of Burke/Screven counties Georgia. Each of their subspecies are primarily Floridian, with M. y. buchholzi extending along the immediate coast of Georgia into southern South Carolina. Topotypes of M. cofaqui from Burke County, Georgia, and Aiken County, South Carolina are phenotypically indistinguishable from both the holotype of M. cofaqui and topotypes of M. c. harrisi. Thus, M …


Two New Nymphalidae From Western North Carolina: New Subspecies Of Speyeria Aphrodite And Phyciodes Batesii, Ronald R. Gatrelle Dec 1998

Two New Nymphalidae From Western North Carolina: New Subspecies Of Speyeria Aphrodite And Phyciodes Batesii, Ronald R. Gatrelle

The Taxonomic Report of the International Lepidoptera Survey

Two new subspecies are described from Macon County, North Carolina, United States. Speyeria aphrodite cullasaja is characterized by dorsal melanism, especially in females, by usually lacking the dorsal FW basal spots in cell Cu1 and Cu2, and by a narrowed buff marginal band on the ventral HW (sometimes absent in females). Phyciodes batesii maconensis males are characterized by wholly yellow ventral hind wings devoid of any dark marginal dusting or whitish crescents; and females occasionally possessing, lightly dusted, brown margins and rarely having a silvered marginal ventral HW spot. PPhyciodes batesii maconensis larvae are gregarious Aster feeders. Females are …


The Rediscovery, Taxonomy, And Biology Of Chlosyne Gorgone Gorgone And Chlosyne Ismeria (Nymphalidae) In Burke County, Georgia, Ronald R. Gatrelle Nov 1998

The Rediscovery, Taxonomy, And Biology Of Chlosyne Gorgone Gorgone And Chlosyne Ismeria (Nymphalidae) In Burke County, Georgia, Ronald R. Gatrelle

The Taxonomic Report of the International Lepidoptera Survey

On April 24, 1993 a colony of Chlosyne gorgone gorgone was found in Orangeburg County, South Carolina, United States. This led to the rediscovery on April 27, 1993 of C. g. gorgone at its type locality in Burke County, Georgia. This species had not been seen or collected anywhere in east coastal Georgia or coastal South Carolina since its description in 1810. The type locality is xeric, scrub oak sandhill. This habitat is generally unsuitable for the survival of later broods. The larvae of nominate gorgone have only been found on Helianthus divaricatus. Topotypical gorgone differ slightly, …


Changes In Small Mammal Community Attributes Associated With Increasing Pine Stand Age In Managed Pine Plantations In Southeastern Virginia, James Douglas Dolan Oct 1998

Changes In Small Mammal Community Attributes Associated With Increasing Pine Stand Age In Managed Pine Plantations In Southeastern Virginia, James Douglas Dolan

Biological Sciences Theses & Dissertations

Loblolly pine plantations were examined at different ages to identify small mammal community attributes in relation to the succession of the plant community. Forest floor and understory plant communities were characterized. Small mammals were collected by Fitch (live) traps and pitfall traps in four age classes during five seasons of study. Fitch live traps and pitfall traps were used in conjunction with one another to obtain the most accurate depiction of the small mammal community. Fitch traps accounted for 65 % of small mammal captures and 7 of 9 species captured. Small mammal abundance and biomass declined with increasing stand …


An Addendum To Anthocharis Midea Dos Passos And Klots 1969: Description Of A New Subspecies From Texas, Ronald R. Gatrelle Oct 1998

An Addendum To Anthocharis Midea Dos Passos And Klots 1969: Description Of A New Subspecies From Texas, Ronald R. Gatrelle

The Taxonomic Report of the International Lepidoptera Survey

This paper verifies and expands upon the information presented by dos Passos and Klots in their 1969 systematic revision of Anthocharis midea. Their restriction of the range of A. midea midea to the coastal islands and immediate coast of Georgia and South Carolina, United States is confirmed and expanded north into southern coastal North Carolina. Their range of A. m. annickae is expanded southward from Virginia to central Georgia. A new subspecies, A. midea texana, is described from Texas. Texana is annickae’s ancestor. It differs from annickae only in having greatly reduced black scaling …


A Strategy For The Future Management Of The Joint Authority Northern Shark Fishery. A Discussion Paper., Tim Bray, Jo Kennedy Jun 1998

A Strategy For The Future Management Of The Joint Authority Northern Shark Fishery. A Discussion Paper., Tim Bray, Jo Kennedy

Fisheries Management Papers

This paper discusses the current status of the Joint Authority Northern Shark Fishery (JANSF), and the major issues affecting it. The main aim of the document is to present a seires of recommendations to enable effective future management of this resource. The paper provides a brief introduction to the JANSF, followed by an examination of the resource base of the fishery (primary species, stock distribution and stock assessment).


Western Rock Lobster Management - Options And Issues, Kevin Donohue Jun 1998

Western Rock Lobster Management - Options And Issues, Kevin Donohue

Fisheries Management Papers

Following the Rock Lobster Industry Advisory Committee meeting of the 3 March 1998 the Minister has advised that his position is that there will be no management changes for the 1998/99 season. The purpose of this paper is primarily to provide information explaining management options and issues for consideration of the long term management of the fishery. The paper is divided into three main sections which detail options that have been identified as having the potential to increase the catch value over the next three years. In the first section, an option for enhancing the catch value by transferring lobsters …


Fisheries Research Report No. 110 - A Research Vessel Survey Of Bottom Types In The Area Of The Abrolhos Islands And Mid-West Trawl Fishery., C. J. Dibden, L. M. Joll Jun 1998

Fisheries Research Report No. 110 - A Research Vessel Survey Of Bottom Types In The Area Of The Abrolhos Islands And Mid-West Trawl Fishery., C. J. Dibden, L. M. Joll

Fisheries Research Reports

To address the concern expressed by Commercial rock lobster fishers operating in the Abrolhos Islands area, that expanding saucer scallop trawl activity was damaging the sea floor biota in areas which they considered good rock lobster habitat and poor scallop habitat, an underwater video survey was conducted by the Fisheries Department Research Division, with the following objectives:

1. Examine, classify and map the benthic habitat of areas currently and historically trawled for scallops in the Abrolhos Islands area and adjacent waters;

2. Examine, classify and map the benthic habitat of areas adjacent to these trawled areas, where potential for conflict …


Summary Of Submissions To Fisheries Management Paper No 108 - Issues Affecting Western Australia's Inshore Crab Fishery, Cathy Campbell Apr 1998

Summary Of Submissions To Fisheries Management Paper No 108 - Issues Affecting Western Australia's Inshore Crab Fishery, Cathy Campbell

Fisheries Management Papers

The summary of submissions is a record of comments offered in respect to the contet of Fisheries Management Paper No. 108 : Issues affecting Western Australia's inshore crab fishery (the Issues Paper) and submitted by groups or individuals who have an interest in inshore crab fishing activity in this State. Concerns of the respective parties included a percieved decline in recreational crab catches at specific locations; instances of conflict between commerical and recreational crabs fishers in Geographe Bay; concern for the types of gear used to take crabs; a substantial rise in the catch of crabs in the Cockburn Sound …


Effect Of Sampling Errors On Estimates Of Recruitment And Fishing Mortality From Separable Virtual Population Analysis, Emmanis Dorval Apr 1998

Effect Of Sampling Errors On Estimates Of Recruitment And Fishing Mortality From Separable Virtual Population Analysis, Emmanis Dorval

Biological Sciences Theses & Dissertations

Separable virtual population analysis (SVPA) models provide estimates of historical recruitment and fishing mortality from analyzing catch data based on the separability of fishing mortality into age specific-gear selection and yearly mortality. These models assume that the catch is randomly sampled and that sampling error is a random variable with constant variance and mean equal to zero. These models do not account for sampling measurement errors that occur when the catch partitioned by age is not measured on every sampling unit without error, and spatio-temporal errors that occur when the observed catch is not representative of the harvested population throughout …


Ecology And Natural History Of The Cow Knob Salamander, Plethodon Punctatus Highton, In West Virginia, Robert B. Tucker Jan 1998

Ecology And Natural History Of The Cow Knob Salamander, Plethodon Punctatus Highton, In West Virginia, Robert B. Tucker

Theses, Dissertations and Capstones

Very little has been written on the ecology and natural history of the Cow Knob salamander, Plethodon punctatus Highton, since it was described by Highton (1971). Plethodon punctatus is known only from the higher elevations of Great North (above 2,800 ft) and Shenandoah (above 3,000 ft.) Mountains in Virginia and West Virginia (Highton, 1972; Conant and Collins, 1991). The type locality is Cow Knob, Pendleton County, West Virginia. Plethodon punctatus is a large (up to 75 mm snout-to-vent length) dorso-ventrally flattened salamander with creamish iridiophore spots on the back and sides, webbed feet for a fossorial lifestyle, and large …


Life History, Ecology, And Low Ph Tolerance Of The Freshwater Prawn, Palaemonetes Kadiakensis Rathbun, In A Mitigated Wetland Of The Green Bottom Wildlife Management Area, West Virginia, Jennifer Ann Aderman Jan 1998

Life History, Ecology, And Low Ph Tolerance Of The Freshwater Prawn, Palaemonetes Kadiakensis Rathbun, In A Mitigated Wetland Of The Green Bottom Wildlife Management Area, West Virginia, Jennifer Ann Aderman

Theses, Dissertations and Capstones

An ecological life history study of the freshwater prawn Palaemonetes kadiakensis was conducted at the mitigated wetland of the Green Bottom Wildlife management Area (GBWMA). Monthly samples were collected from November 1996 through November 1997. In addition, weekly samples were collected from May through November for growth and reproductive analysis. Monthly samples yielded 520 prawns. Palaemonetes kadiakensis had a one-year life cycle, with all adults dying by September. Males averaged 23.82 mm (range = 14.15 to 36.75 mm) and females averaged 26.78mm (range = 15.06 to 38.60 mm) in length. Males averaged 0.087g (range = 0.014to 0.293 g) and females …


An Assessment Of The Prevalence Of The Bass Tapeworm, Proteocephalus Ambloplitis, And Other Parasites In Five Species Of Basses From River And Lake Ecosystems In West Virginia, J. Alyce Bradbury Jan 1998

An Assessment Of The Prevalence Of The Bass Tapeworm, Proteocephalus Ambloplitis, And Other Parasites In Five Species Of Basses From River And Lake Ecosystems In West Virginia, J. Alyce Bradbury

Theses, Dissertations and Capstones

Two-hundred and fifteen basses were collected from four river sites (Racine Locks and Dam, Robert C. Byrd Locks and Dam; Ashland, KY—Ohio River; London Locks and Dam—Kanawha River) and five reservoir sites (Beech Fork Lake, East Lynn Lake, Summersville Lake, Burnsville Lake, and Stonewall Jackson Lake,). The five species of bass caught were: largemouth bass, Micropterus salmoides; smallmouth bass, Micropterus dolomieui; spotted bass, Micropterus punctulatus; white bass, Morone chrysops; and hybrid bass, Morone chyrsops x Morone saxatilis. Basses were collected by three methods: 1) local anglers (hook and line), 2) gill netting surveys; and 3) …


Improving Recovery Planning For Threatened And Endangered Species, Theodore Foin, Seth Riley, Anitra Pawley, Debra Ayres, Tina Carlsen, Peter Hodum, Paul Switzer Jan 1998

Improving Recovery Planning For Threatened And Endangered Species, Theodore Foin, Seth Riley, Anitra Pawley, Debra Ayres, Tina Carlsen, Peter Hodum, Paul Switzer

Faculty Research & Creative Activity

No abstract provided.


The Use Of Emergent Rocks As Refugia For The Cheat Mountain Salamander, Plethodon Nettingi Green, Beth Anne Pauley Jan 1998

The Use Of Emergent Rocks As Refugia For The Cheat Mountain Salamander, Plethodon Nettingi Green, Beth Anne Pauley

Theses, Dissertations and Capstones

Plethodon nettinqi was listed as a threatened species in 1989 by the United States Fish and Wildlife Service (Pauley, 1991). Its total range is within 5 counties in eastern West Virginia. There are fewer then 60 disjunct populations known and most populations are above 3,000 ft. and are associated with emergent rocks or narrow ravines with Rhododendron. It is hypothesized the P. netting! survived lumbering practices at the turn of the century by taking refuge beneath large emergent rocks and narrow ravines with Rhododendron. This study examined environmental factors associated with emergent rocks that might regulate the distribution of P. …


Improving Recovery Planning For Threatened And Endangered Species, Theodore C. Foin, Seth P. Riley, Anitra L. Pawley, Debra R. Ayres, Tina M. Carlsen, Peter J. Hodum, Paul V. Switzer Jan 1998

Improving Recovery Planning For Threatened And Endangered Species, Theodore C. Foin, Seth P. Riley, Anitra L. Pawley, Debra R. Ayres, Tina M. Carlsen, Peter J. Hodum, Paul V. Switzer

Faculty Research & Creative Activity

No abstract provided.


Ecological Life History Of Caenis Amica Hagen (Emphemeroptera: Caenidae) From The Mitigated Area Of Green Bottom Wildlife Management Area, Cabell County, West Virginia, Gail Lynn Perrine Jan 1998

Ecological Life History Of Caenis Amica Hagen (Emphemeroptera: Caenidae) From The Mitigated Area Of Green Bottom Wildlife Management Area, Cabell County, West Virginia, Gail Lynn Perrine

Theses, Dissertations and Capstones

The ecological life history of a population of Caenis amica Hagen from the Green Bottom Wildlife Management Area was studied from November 1996 to November 1997. Water quality data and 2,505 larvae were collected from the newly mitigated area of Green Bottom Swamp. Total body lengths of larvae were measured using a computer-digitizing program. These results indicated a bivoltine life cycle. Most larvae were found in the spring and summer months of April, June, and July. The highest peak of larvae (1,035) occurred in July. The pH values ranged from 7.0 to 8.0 with a mean of 7.6. Temperatures ranged …


Population Biology Of Intraspecific Polyploidy In Grasses, Kathleen H. Keeler Jan 1998

Population Biology Of Intraspecific Polyploidy In Grasses, Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

Polyploidy is the duplication of an entire nuclear genome, whether diploid or higher level (Stebbins, 1971; Thompson and Lumaret, 1992) and a frequent occurrence in plants. Stebbins (1971) estimated that 30-35% of flowering plant species are polyploid, and that many more had a polyploid event in their evolutionary history, including all members of such important families as the Magnoliaceae, Salicaceae, and Ericaceae. Goldblatt (1980) estimated 55%, but probably up to 75%, of monocotyledons had at least one polyploid event in their history, using the criterion that if the species has a base number higher than n = 13 it is …


Chondrocranial Anatomy And Skeletogenesis In Dendrobates Auratus, Rafael O. De Sá, Shannon Hill Jan 1998

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.


Declines In Benthic Macroinvertebrate Populations In Southern Lake Michigan, 1980–1993, Thomas F. Nalepa, David J. Hartson, David L. Fanslow, Gregory A. Lang, Stephen J. Lozano Jan 1998

Declines In Benthic Macroinvertebrate Populations In Southern Lake Michigan, 1980–1993, Thomas F. Nalepa, David J. Hartson, David L. Fanslow, Gregory A. Lang, Stephen J. Lozano

United States Department of Commerce: Staff Publications

Densities of the major benthic macroinvertebrate groups declined dramatically at sites shallower than 50 m in southern Lake Michigan between 1980 and 1993. Declines in Diporeia, Oligochaeta, and Sphaeriidae ranged from 40 to 75% at these depths. Total densities declined from 16 800·m–2 in 1980–1981 to 4,800·m–2 in 1992–1993 at sites in the 16–30 m depth interval and from 21,300 to 11,300·m–2 at sites in the 31–50 m depth interval. Changes at sites deeper than 50 m were minimal; only sphaeriids declined to any extent. Declines in oligochaetes and sphaeriids occurred uniformly throughout the nearshore region …