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Articles 1801 - 1830 of 1892

Full-Text Articles in Terrestrial and Aquatic Ecology

Land Use Status And Trends Of Potential Whooping Crane Release Sites In Central Florida, Mary Anne Bishop Jan 1992

Land Use Status And Trends Of Potential Whooping Crane Release Sites In Central Florida, Mary Anne Bishop

Proceedings of the North American Crane Workshop

Three areas in central Florida, identified as potential sites for the reintroduction of a nonmigratory flock of whooping cranes (Grus americana), were evaluated. and ranked as to their priority for reintroduction based on their land use status and trends. The Kissimmee Prairie, including Three Lakes Wildlife Management Area, Prairie-Lakes State Preserve, and the National Audubon Society's Kissimmee Prairie Sanctuary was ranked first, the Webb Wildlife Management Area second, and Myakka River State Park third. Primary criteria used for each site and its surrounding lands included acreage, ownership, management, public use, access, potential threats, and the potential to support …


Relationship Of Channel Maintenance Flows To Whooping Crane Use Of The Platte River, Craig A. Faanes, David B. Bowman Jan 1992

Relationship Of Channel Maintenance Flows To Whooping Crane Use Of The Platte River, Craig A. Faanes, David B. Bowman

Proceedings of the North American Crane Workshop

Periodic high flows in the Platte River are necessary to scour vegetation and redistribute sediment in the stream channel. Peak and mean annual flows have been reduced by as much as 70% from pre-development times, but channel maintenance flows still occur, although at a much reduced frequency and magnitude of occurrence. Use of the Platte River by migrant whooping cranes (Grus americana) in recent years appears to be related to the recent occurrence of flows in excess of 8,000 cfs for 5 or more consecutive days.


Release Of Sandhill Crane Chicks Hand-Reared With Artificial Stimuli, Robert H. Horwich, John Wood, Ray Anderson Jan 1992

Release Of Sandhill Crane Chicks Hand-Reared With Artificial Stimuli, Robert H. Horwich, John Wood, Ray Anderson

Proceedings of the North American Crane Workshop

Greater sandhlll crane chicks (Grus canadensis tabida) were hand-reared using moveable puppets and vocalizing crane models as substitute parents. Their parental attachment was transferred to a crane-costumed human who introduced them to a wild environment and to wild foods. Five chicks were gentle-released in Wisconsin when 3.5 months old, a period of high sociality, and all successfully joined wild cranes. Following their first few weeks in association with wild cranes, their behavior was normal and comparable to that of wild chicks and they achieved normal flight distance from humans. Four of the 5 were relocated in Wisconsin the …


Whooping Cranes At The San Antonio Zoo, Jacqueline A. Lauver Jan 1992

Whooping Cranes At The San Antonio Zoo, Jacqueline A. Lauver

Proceedings of the North American Crane Workshop

Since April, 1956, when an injured whooping crane (Grus americana) was received for rehabilitation, the San Antonio Zoo has maintained these birds in the collection and is 1 of only 2 zoos to have raised them. The zoo's management efforts, combined with favorable climatic cbnditions and water sources have contributed to a successful breeding program. The whooping crane is 1 of 7 crane species successfully bred, and 1 of 8 crane species currently in the collection.


The Contingency Plan For Federal-State Cooperative Protection Of Whooping Cranes, James C. Lewis Jan 1992

The Contingency Plan For Federal-State Cooperative Protection Of Whooping Cranes, James C. Lewis

Proceedings of the North American Crane Workshop

A "Contingency Plan for Federal-State Cooperative Protection of Whooping Cranes" was developed in 1985 to protect migrating whooping cranes (Grus americana). Thirteen states and the U.s. Fish and Wildlife Service implemented the plan in summer 1985. One state and one feq,eral employee, and alternates, are appointed as the "key contact" individuals within each state. Reports of sightings of whooping cranes are forwarded to these key contacts and they coordinate the response to sightings. An important part of the plan is education activities designed to increase the public's ability to identify whooping cranes and to encourage the reporting of …


Introduction Of Whooping Cranes In Eastern North America, James C. Lewis, F. Graham Cooch Jan 1992

Introduction Of Whooping Cranes In Eastern North America, James C. Lewis, F. Graham Cooch

Proceedings of the North American Crane Workshop

Whooping cranes (Grus americana) historically occurred throughout most of North America. A migration route last used prior to 1857 crossed the Appalachians to Atlantic Coast wintering grounds in coastal areas of New Jersey, South Carolina and river deltas farther south. The species disappeared from most eastern North American locations in the late 1800's. The winter 1987 population consisted of 43 captive birds and 154 in 2 wild subpopulations. Pursuant to both Canadian and u.s. recovery plans, sites in Michigan-Ontario, Georgia and Rorida are being considered as potential release locations for establishing an eastern population. Cross-fostering, gentle release and …


Mate Recognition And Fidelity In Captive Sandhill Cranes, Peter W. Shannon Jan 1992

Mate Recognition And Fidelity In Captive Sandhill Cranes, Peter W. Shannon

Proceedings of the North American Crane Workshop

Two pairs of greater sandhill cranes (Grus canadensis tabida) were maintained at Audubon Park Zoo in separate but adjacent exhibits. The male of pair #2 was killed and due to medical problems associated with the female of pair #1, male #1 and female #2 were placed together. These birds subsequently bonded but did not nest. Following a 17 month separation, female #1 was moved to an area where she could hear but not see male #1 and female #2 . Almost immediately, male #1 began attempting to move himself closer to female #1 . They were placed together, …


Whooping Crane Habitat Alteration Analysis At Aransas National Wildlife Refuge, Texas, C. Lee Sherrod, Richard Medina Jan 1992

Whooping Crane Habitat Alteration Analysis At Aransas National Wildlife Refuge, Texas, C. Lee Sherrod, Richard Medina

Proceedings of the North American Crane Workshop

Aquatic, wetland, and upland habitat changes were quantified within the approximate critical habitat of the endangered whooping crane (Grus americana) along the Gulf Intracoastal Waterway (GIWW) through Aransas National Wildlife Refuge and San Antonio, Bay, Texas. Study procedures employed comparative analysis of pre-GIWW (1930) and present (1986) aerial photography to provide a basis for the assessment of positive and negative impacts of the construction, operation and maintenance of the GIWW, principally on the whooping crane, but also on biota in general. Thirteen habitat mapping categories were utilized to describe an approximately 1,830 m wide corridor along the GIWW …


Lead Poisoning In A Whooping Crane, S. Bret Synder, Michael J. Richard, John P. Thilsted, Roderick C. Drewien, James C. Lewis Jan 1992

Lead Poisoning In A Whooping Crane, S. Bret Synder, Michael J. Richard, John P. Thilsted, Roderick C. Drewien, James C. Lewis

Proceedings of the North American Crane Workshop

The first known incident of lead poisoning in a whooping crane (Grus americana) occurred as the affected bird completed its second migration from Grays Lake National Wildlife Refuge (NWR), Idaho to Bosque del Apache NWR, New Mexico. It fell ill about 4 1/2 weeks after reaching the winter site and was captured. The bird exhibited signs of anorexia and starvation, weakness with drooped wings, greenish watery diarrhea and an unusual gaping of the mouth with abnormal swallowing motions. Blood showed marked polychromasia (>50%) and reticulocytosis (>80%) of RBC's. Serum chemistry values were not diagnostic. A radiograph …


Crane Migration In Northern New Mexico, Dale W. Stahlecker Jan 1992

Crane Migration In Northern New Mexico, Dale W. Stahlecker

Proceedings of the North American Crane Workshop

Greater sandhill cranes (Grus canadensis tabida) and foster-reared whooping cranes (G. americana) were monitored on a 345 km migration between their traditional stopover in southcentral Colorado and their winter grounds in central New Mexico during 4 autumns (1984-87) and 1 spring (1985). Autumn sandhill crane counts totaled 17,363 in 1984, 9,317 in 1985, 29,053 in 1986, and 26,552 in 1987. Peak flights of over 7,000 cranes in 1 day were recorded in both 1986 and 1987. More than 50% of the cranes were counted on just 4 days in 1984, 1986 and 1987. At least 27% …


Nesting Of Greater Sandhill Cranes On Seney National Wildlife Refuge, Richard P. Urbanek, Theodore A. Bookhout Jan 1992

Nesting Of Greater Sandhill Cranes On Seney National Wildlife Refuge, Richard P. Urbanek, Theodore A. Bookhout

Proceedings of the North American Crane Workshop

During 1987, 59 nests of 57 pairs of greater sandhill cranes (Grus canadensis tabida) were located, mainly from the air, on or near the Seney National Wildlife Refuge, Michigan, and 52 nests were ground-checked. Nests were in available palustrine classes without tree canopies. Only 19% were in Sphagnum bogs, in which most nests from other areas of the Upper Peninsula have been found. Cattail (Typha latifolia) marshes, most prevalent in the managed area of the refuge, contabed 44% of the nests, and sedge (Carex spp.) marshes accounted for 37%. Important co-dominant plant species were leatherleaf …


Renesting Of Mississippi Sandhill Cranes In Jackson County, Mississippi 1965–1989, Jacob M. Valentine Jr. Jan 1992

Renesting Of Mississippi Sandhill Cranes In Jackson County, Mississippi 1965–1989, Jacob M. Valentine Jr.

Proceedings of the North American Crane Workshop

Among 118 active nests of Mississippi sandhill cranes (Grus canadensis pulla) in Jackson County, Mississippi, 1%5-1989, 13 were renests. Three chicks from 19 wild and 3 from 3 Patuxent Wildlife Research Center (PWRC) switched eggs hatched in 13 first nests, but 5 died early and 1 after 2 weeks. Ten eggs were dead (infertile or the embryos died) in or at the nest. Two clutches (3 eggs) were destroyed by mammalian predators, 2 eggs were taken for captive propagation, and 1 was pecked and destroyed by the crane pair. Three chicks hatched from 22 wild eggs and 1 …


The Study Of Relatedness And Genetic Diversity In Cranes, George F. Gee, Herbert C. Dessauer, Jonathan Longmire, W. Elwood Briles, Raymond C. Simon Jan 1992

The Study Of Relatedness And Genetic Diversity In Cranes, George F. Gee, Herbert C. Dessauer, Jonathan Longmire, W. Elwood Briles, Raymond C. Simon

Proceedings of the North American Crane Workshop

The U.S. Fish and Wildlife Service (Service) is responsible for recovery of endangered species in the wild and, when necessary, maintenance in captivity. These programs provide an immediate measure of insurance against extinction. A prerequisite inherent in all of these programs is the preservation of enough genetic diversity to maintain a viable population and to maintain the capacity of the population to respond to change. Measures of genetic diversity examine polymorphic genes that are not influenced by selection pressures. Examples of these techniques and those used to determine relatedness are discussed. Studies of genetic diversity, electrophoresis of blood proteins, relatedness, …


A Laboratory Study Of Predation On The Trinidadian Guppy, Poecilia Reticulata, By Two Natural Piscine Predators: Effects Of Predator Size, Prey Size, And Habitat Complexity, Hayden Thomas Mattingly Oct 1991

A Laboratory Study Of Predation On The Trinidadian Guppy, Poecilia Reticulata, By Two Natural Piscine Predators: Effects Of Predator Size, Prey Size, And Habitat Complexity, Hayden Thomas Mattingly

Biological Sciences Theses & Dissertations

Test populations of different-sized guppies, Poecilia reticulata, were exposed to individuals of two natural predatory species, the pike cichlid Crenicichla a/ta and the killifish Rivulus harti, under conditions of varying prey (guppy) density and habitat complexity in the laboratory. Rivulus fed most frequently on newborn and juvenile guppies < 14 mm. Crenicichla consumed more and larger guppies than did Rivulus. The mean guppy size eaten by Crenicichla was dependent on the length of the individual predator, but as a group, the 15 Crenicichla tested were non-selective with respect to guppy size and gender. The prey gender preference of Rivulus could not he determined …


Population Dynamics Of Feral House Mice And Meadow Voles On A Dredge Disposal Site, Georgia E. Kratimenos Oct 1991

Population Dynamics Of Feral House Mice And Meadow Voles On A Dredge Disposal Site, Georgia E. Kratimenos

Biological Sciences Theses & Dissertations

The population dynamics of two species was studied for one year on Craney Island in Portsmouth, Virginia. This dredge disposal site provided good habitat for the house mouse, Mus musculus, whose opportunistic behaviors can withstand the sudden changes in a dynamic environment. Although the site was not optimal habitat, a population of Microtus pennsylvanicus, the meadow vole, was sustained there. Of the seven species of small mammals captured, 65% were house mice and 28% were meadow voles. Meadow voles were more successful at establishing short periods of residency than were house mice; on average, each meadow vole was …


Community Structure Of The Macrobenthos In Back Bay, Virginia, Michael F. Lane Oct 1991

Community Structure Of The Macrobenthos In Back Bay, Virginia, Michael F. Lane

Biological Sciences Theses & Dissertations

A study of the subtidal macrobenthos in Back Bay, Virginia was conducted to examine community structure in relation to sedimentary and water quality characteristics. Samples were collected in August and November of 1987 and February and May of 1988 at ten stations.

Three site groups and three temporal groups were identified by cluster analyses of species abundance. Species composition between site groups was relatively homogeneous and eight species accounted for most of the variation between site groups. A comparison of plots of the biological and physical data in discriminant space suggested that variations in the biological data between site groups …


The Identification, Distribution, And Status Of The Threatened Dismal Swamp Shrew (Sorex Longirostris Fisheri), Thomas M. Padgett Oct 1991

The Identification, Distribution, And Status Of The Threatened Dismal Swamp Shrew (Sorex Longirostris Fisheri), Thomas M. Padgett

Biological Sciences Theses & Dissertations

Southeastern shrews (Sorex longirostris) were trapped throughout southeastern Virginia and northeastern North Carolina to determine if any morphological characters could

be identified that would aid in the identification and distribution of the threatened subspecies Sorex l._ fisheri, endemic to the Great Dismal Swamp, the more upland nominate subspecies Sorex l. longirostris, and possible intergrades between the two subspecies. Animals were classified a priori into three groups, based on their location of capture. Animals collected from the Great Dismal Swamp National Wildlife Refuge (GDSNWR) and associated bottomland habitats were designated as "fisheri", animals collected farthest from the Swamp as "longirostris", and …


Phytoplankton In Lake Drummond And Two Drainage Ditches In The Great Dismal Swamp, Virginia, Christine Gregory Phillips Jul 1990

Phytoplankton In Lake Drummond And Two Drainage Ditches In The Great Dismal Swamp, Virginia, Christine Gregory Phillips

Biological Sciences Theses & Dissertations

A twelve month study was conducted on the phytoplankton of Lake Drummond and Washington and Jericho Ditches from December 1988 to November 1989. Surface water samples were collected for nutrient and chlorophyll analysis from June 1989 to November 1989. The dominant phytoplankton component was the pico-nanoplankton (< 3 micron) category. A total of 57 species were identified from Lake Drummond, 51 species from Washington Ditch, and 31 species from the Jericho Ditch. Three major phytoplankton groups were identified at these sites: bacillariophyceans, cyanophyceans and cryptophyceans. The dominant species was the diatom Asterionella formosa. Nutrient and chlorophyll concentrations increased from summer to fall. Based on nutrient and chlorophyll g concentrations and species diversity indices, Lake Drummond is classified as eutrophic.


Description Of The Tadpoles Of Gastrophryne Pictiventris And Nelsonophryne Aterrima (Anura: Microhylidae), With A Review Of Morphological Variation In Free-Swimming Microhylid Larvae, Maureen A. Donnelly, Rafael O. De Sá, Craig Guyer Jun 1990

Description Of The Tadpoles Of Gastrophryne Pictiventris And Nelsonophryne Aterrima (Anura: Microhylidae), With A Review Of Morphological Variation In Free-Swimming Microhylid Larvae, Maureen A. Donnelly, Rafael O. De Sá, Craig Guyer

Biology Faculty Publications

The tadpoles of Gastrophryne pictiventris and Nelsonophryne aterrima are described based on material collected in Costa Rica and Panama, respectively. The tadpole of G. pictiventris resembles those of the other species of Gastrophryne. The tadpole of N. aterrima differs from other New World microhylid tadpoles in location of the vent tube (medial), the spiracular opening (ventral to the gut), and eyes (dorsolateral). The unique configuration of mouthparts in N. aterrima is described. Morphological variation in microhylid tadpoles is reviewed and six larval characters are analyzed cladistically for IO New World microhylid genera.


Historic Trends In The Distribution And Populations Of Estuarine Marsh Birds Of The Connecticut River, Robert J. Craig May 1990

Historic Trends In The Distribution And Populations Of Estuarine Marsh Birds Of The Connecticut River, Robert J. Craig

Storrs Agricultural Experiment Station

No abstract provided.


An Analysis Of External Features As Predictors Of Reproductive Status In Small Mammals, Kenneth Wayne Mccravy Apr 1990

An Analysis Of External Features As Predictors Of Reproductive Status In Small Mammals, Kenneth Wayne Mccravy

Biological Sciences Theses & Dissertations

Reproductive status in specimens of nine populations of seven species of small mammals was evaluated by examining the external reproductive features of nipple size, condition of the pubic symphysis, and vaginal condition and, in males, testis position. Usefulness of these external features in predicting true monthly breeding rates was evaluated by comparing predictions of breeding rates with true rates based on necropsy. Accuracy of predictions of reproductive status of individuals based on single external features and combinations of external features and body measurements was then analyzed at a finer level by comparing those predictions with results of necropsy of the …


Fisheries Research Report No. 87 - The Recreational Marron Fishery In Western Australia, Summarised Research Statistics, 1971-1987, N. M. Morrissy, C. J. Fellows Jan 1990

Fisheries Research Report No. 87 - The Recreational Marron Fishery In Western Australia, Summarised Research Statistics, 1971-1987, N. M. Morrissy, C. J. Fellows

Fisheries Research Reports

The freshwater crayfish Cherax tenuimanus, called marron, provides an important recreational fishery in the south-west of Western Australia. The annual fishing catch and fishing effort have been monitored by a log book research programme and an end-of season telephone survey since the 1971/72 season.

Following the 1986/87 fishing season, the fishery remained closed for two seasons (1987/88 and 1988/89) to permit stocks to recover from the effects of high total fishing effort and unfavourable water conditions over the preceding seasons

This paper provides a detailed account of the catch and effort statistics to the close of the 1986/87 fishing season, …


Fisheries Research Report No. 92 - Spread Of The Introduced Yabbie Cherax Albidus Clark, 1936 In Western Australia, N. M. Morrissy, G. Cassells Jan 1990

Fisheries Research Report No. 92 - Spread Of The Introduced Yabbie Cherax Albidus Clark, 1936 In Western Australia, N. M. Morrissy, G. Cassells

Fisheries Research Reports

This report presents information on the probable original introduction of the eastern Australian yabbie to farm dams in the Wheat-belt Region of the southwest of Western Australia (in 1932 at Narembeen); the probable type of yabbie (the "White Yabby", Cherax albidus Clark 1936 ) and source (Miram Swamp in the Victorian Wimmera); and, in 1985, the first voicing of concern over the spread of yabbies to natural habitats, particularly in the higher rainfall region of the southwest, together with current national and international concerns and advice on introduced aquatic species.

Commercial harvesting ("extensive" aquaculture) of existing yabbie stocks in wheat-belt …


Colony Survivorship In Pogonomyrmex Occidentalis, Western Harvester Ant, In Western Nebraska, Kathleen H. Keeler Nov 1988

Colony Survivorship In Pogonomyrmex Occidentalis, Western Harvester Ant, In Western Nebraska, Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

Little is known about the life span of individual ant colonies (Keeler, 1981), even though the dynamics of some species, such as harvester ants, are crucial to the structure of plant and animal communities (e.g., Brown et al., 1979). This note reports the results of 10 years of observations on a population of harvester ants.

Fifty-six mounds of Pogonomyrmex occidentalis Cresson (Hymenoptera: Formicidae), western harvester ant, were permanently marked with aluminum tags in August 1977. The site, about 1 ha just south of the University of Nebraska's Cedar Point Biological Station, Keith Co., Nebraska, was within a pasture subject to …


The Distribution Of Zooplankton In Selected Oregon Lakes, Mary Elizabeth Claska Aug 1988

The Distribution Of Zooplankton In Selected Oregon Lakes, Mary Elizabeth Claska

Dissertations and Theses

Zooplankton samples were collected from 166 Oregon lakes. The lakes included a wide range in size, trophic status, and water quality. Lakes were located throughout the state. Zooplankton were identified using standard taxonomic keys and counted. Seventy-four species were identified from the 200 total samples, including 32 species of cladocera, 22 copepods, and 11 rotifers. Two species of copepod were recorded for the first time in Oregon: Diaptomus mississippiensis and Diaptomus pallidus. Seven species had widespread distributions throughout most of the watersheds in the state. Seventeen other species had distributions restricted to eastern, central, or western Oregon. The remaining …


Age And Growth Of The Tautog, Tautoga Onitis (Pisces: Labridae), From Lower Chesapeake Bay And Coastal Waters Of Virginia, E. Brian Hostetter Apr 1988

Age And Growth Of The Tautog, Tautoga Onitis (Pisces: Labridae), From Lower Chesapeake Bay And Coastal Waters Of Virginia, E. Brian Hostetter

Biological Sciences Theses & Dissertations

The tautog, Tautoga onitis (Pisces: Labridae), is rapidly gaining popularity in Virginia by anglers, spearfishermen and specialized commercial interests. In Virginia, tautog are seasonally abundant on hard bottom substrates in nearshore (ca. 2-10 m) habitats and inhabit offshore wrecks and reef areas (ca. 10-30 m) year round. Habitat restriction and slow growth of the species coupled with recent technological advances in marine electronics which simplify locating tautog populations by user groups may contribute to overexploitation of tautog within the region.

Tautog were collected over a two year period from the lower Chesapeake Bay and nearshore waters of the Atlantic Ocean …


A Taxonomic Survey Of The Family Gyrinidae (Coleoptera) Of The State Of Virginia, Jerrold R. Harris Jul 1987

A Taxonomic Survey Of The Family Gyrinidae (Coleoptera) Of The State Of Virginia, Jerrold R. Harris

Biological Sciences Theses & Dissertations

The aquatic insect fanua of Virginia is not very well known. This is especially true of the order Coleoptera. There are few taxonomic studies on the families of Coleoptera found within the state, and one of the least known is the family Gyrinidae. It is the intent of this study to determine what species of Gyrinidae are found within the state and where they are found. Collections of the beetles were made throughout the state from March to December.

Twenty-one species of Gyrinidae were identified in Virginia, nine species of Dineutus and 12 species of Gyrinus. The family is distributed …


The Relationship Between Habitat Structure And Small Mammal Communities In Southeastern Virginia And Northeastern North Carolina, Roger Keith Everton Jul 1985

The Relationship Between Habitat Structure And Small Mammal Communities In Southeastern Virginia And Northeastern North Carolina, Roger Keith Everton

Biological Sciences Theses & Dissertations

A variety of terrestrial habitats was pitfall trapped in the vicinity of the Great Dismal Swamp of eastern Virginia and North Carolina to evaluate the small mammal community within the region. Habitat variables were measured at the end of the growing season on 21 0.25 ha grids. Four multivariate tests were used to examine the small mammal communities, their relationship with habitat structure, and the role of habitat selection in community structure.

Cluster and ordination analysis revealed the existence of two distinct associations of small mammals, and their habitat types, within the region. The small mammal associations were interpreted as …


A Biochemical And Genetic Analysis Of The American Shad Alosa Sapidissima Migrating Into The Chesapeake Bay, Edward Norbert Sismour Jul 1985

A Biochemical And Genetic Analysis Of The American Shad Alosa Sapidissima Migrating Into The Chesapeake Bay, Edward Norbert Sismour

Biological Sciences Theses & Dissertations

Seven enzymes extracted from heart and liver tissues of American shad Alosa sapidissima captured during migrations into the Chesapeake Bay and Nansemond River were electrophoretically surveyed. Malate dehydrogenase and nonspecific esterase displayed polymorphic loci. The esterase polymorphism was used as a biochemical genetic marker to analyze the shad migration through the southern Chesapeake Bay. The genetic composition of the shad migration changed significantly over time indicating that this migration is probably composed of multiple, genetically divergent spawning populations. Results of this study are subject to differing interpretations. Observed temporal heterogeneity may result from separation of northern and James River stocks …


Gametogenesis En Chthonerpeton Indistinctum (Gymnophiona: Typhlonectidae), Rafael O. De Sá, Nibia Berois Jan 1985

Gametogenesis En Chthonerpeton Indistinctum (Gymnophiona: Typhlonectidae), Rafael O. De Sá, Nibia Berois

Biology Faculty Publications

RESUMEN:

Histológicamente, las gónadas de Chthonerpeton indistinctum son similares a las ya descritas para otras especies del orden Gymnophiona. Los lóbulos testiculares se hallan compartimentados en unidades estructurales denominadas lóculos. La espermatogénesis ocurre en cistos sincrónicos de células germinales. Durante la espermiogénesis se identifican cuatro estados consecutivos de desarrollo: 1) cistos de espermátidas redondeadas; 2) cistos de espermátidas arrifionadas; 3) cistos de espermátidas bastoniformes y 4) espermátidas en ramillete.

El análisis histológico de los ovarios mostró la presencia de tres estados en la maduración de los folículos ováricos. Estas etapas pueden ser identificadas de acuerdo a: 1) ubicación del folículo …