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Full-Text Articles in Parasitology
Why American Higher Education Needs Parasitologists, John J. Janovy Jr.
Why American Higher Education Needs Parasitologists, John J. Janovy Jr.
John J. Janovy, Jr. Publications
Addresses four topics that characterize the discipline of parasitology and are largely missing from our national conversation in the United States about education, especially at the college and university level. Those topics are the production of transferable skills; our perceptions of the world, especially the natural world; access to reasonably difficult problems in natural settings; and intellectual epidemiology, or the movement of ideas, innovations, and cultural items through populations. These topics have been a part of the author's discussions with fellow parasitologists for at least half a century, beginning with his choice to pursue a graduate degree under the supervision …
Community Structure And Seasonal Dynamics Of Dactylogyrus Spp. (Monogenea) On The Fathead Minnow (Pimephales Promelas) From The Salt Valley Watershed, Lancaster County, Nebraska, Alaine Knipes, John J. Janovy Jr.
Community Structure And Seasonal Dynamics Of Dactylogyrus Spp. (Monogenea) On The Fathead Minnow (Pimephales Promelas) From The Salt Valley Watershed, Lancaster County, Nebraska, Alaine Knipes, John J. Janovy Jr.
John J. Janovy, Jr. Publications
The gill monogene communities of Pimephales promelas (fathead minnow) in three distinct sites on converging streams were investigated from 2004 to 2006 in three different seasons. Thirty collections of P. promelas were made in southeastern Nebraska along three converging tributaries: Elk Creek (40.88534°N, 96.83366°W), West Oak Creek (40.9082°N, 96.81432°W), and Oak Creek (40.91402°N, 96.770583°W), Lancaster County, Nebraska. In all, 103 P. promelas were collected from Elk Creek, 115 from West Oak Creek, and 78 from Oak Creek and examined for gill monogenes. Among the P. promelas collected, 93.5% were infected with up to three species of Dactylogyrus, including Dactylogyrus …
Comparative Life Cycles And Life Histories Of North American Rhabdias Spp. (Nematoda: Rhabdiasidae): Lungworms From Snakes And Anurans, Gabriel J. Langford, John J. Janovy Jr.
Comparative Life Cycles And Life Histories Of North American Rhabdias Spp. (Nematoda: Rhabdiasidae): Lungworms From Snakes And Anurans, Gabriel J. Langford, John J. Janovy Jr.
John J. Janovy, Jr. Publications
The present study used experimental infections to compare the life cycles and life histories of 6 Rhabdias spp. infecting snakes and anurans. Free-living development of anuran lungworms was primarily limited to heterogonic reproduction, and females utilized matricidal endotoky exclusively, whereas snake lungworms primarily reproduced homogonically and, when heterogonic reproduction occurred, females used a combination of releasing eggs and matricidal endotoky. Infective snake lungworms survived for longer periods in fresh water compared to anuran worms. Infective anuran lungworms penetrated into the skin of frogs and toads; few infections resulted from per os infections. In contrast, snake lungworms were unable to penetrate …
Redescription Of The Frog Bladder Fluke Gorgoderina Attenuata From The Northern Leopard Frog, Rana Pipiens, Matthew G. Bolek, Scott D. Snyder, John J. Janovy Jr.
Redescription Of The Frog Bladder Fluke Gorgoderina Attenuata From The Northern Leopard Frog, Rana Pipiens, Matthew G. Bolek, Scott D. Snyder, John J. Janovy Jr.
John J. Janovy, Jr. Publications
Morphological characters used to differentiate North American bladder flukes, Gorgoderina spp., are problematic and different authors use different morphological characteristics for distinguishing species. More importantly, no type specimens exist for four of the 12 North American species infecting anuran and caudatan hosts. A redescription of Gorgoderina attenuata (Stafford, 1902) Stafford, 1905 is based on new collections from 6 species of anurans from Arkansas, Nebraska, New York, and Wisconsin. Morphological comparisons between gravid G. attenuata recovered from bullfrogs and northern leopard frogs indicated statistically significant differences in 11 of 28 morphological characters examined. However, there was overlap among all of these …
Alternative Life Cycle Strategies And Colonization Of Young Anurans By Gorgoderina Attenuata In Nebraska, Matthew G. Bolek, Scott D. Snyder, John J. Janovy Jr.
Alternative Life Cycle Strategies And Colonization Of Young Anurans By Gorgoderina Attenuata In Nebraska, Matthew G. Bolek, Scott D. Snyder, John J. Janovy Jr.
John J. Janovy, Jr. Publications
Studies on life cycles and epizootiology of North American frog bladder flukes indicate that adult frogs become infected predominantly by ingesting tadpoles or other frogs that serve as second intermediate hosts for gorgoderid metacercariae. Other studies have indicated that newly metamorphosed frogs are rarely infected with these parasites because they are gape-limited predators that cannot feed on large intermediate hosts such as tadpoles and other frogs. We examined the role of potential intermediate hosts in the recruitment of the frog bladder fluke, Gorgoderina attenuata, to metamorphosed northern leopard frogs, Woodhouse’s toads, and bullfrogs from western Nebraska. We completed the …
Why We Have Field Stations: Reflections On The Cultivation Of Biologists, John J. Janovy Jr., Krista M. Major
Why We Have Field Stations: Reflections On The Cultivation Of Biologists, John J. Janovy Jr., Krista M. Major
John J. Janovy, Jr. Publications
For a resident of the state of Nebraska, the Cedar Point Biological Station (CPBS), located in scenic limestone bluffs below Kingsley Dam, an earth-filled artificial mountain that impounds a lake 35 kilometers long and 5 kilometers wide, is a bargain in American higher education. In three weeks a student can earn four credits of upper-division coursework, get original research experience, and, most importantly—especially in an educational milieu increasingly characterized by electronic content and electronic course management—get his or her hands on some live wild plants and animals in an appropriate ecological context. This encounter with nature is typically the first …
Gregarines On A Diet: The Effects Of Host Starvation On Gregarina Confusa Janovy Et Al., 2007 (Apicomplexa: Eugregarinida) In Tribolium Destructor Uyttenboogaart, 1933 (Coleoptera: Tenebrionidae) Larvae, Jodi Schreurs, John J. Janovy Jr.
Gregarines On A Diet: The Effects Of Host Starvation On Gregarina Confusa Janovy Et Al., 2007 (Apicomplexa: Eugregarinida) In Tribolium Destructor Uyttenboogaart, 1933 (Coleoptera: Tenebrionidae) Larvae, Jodi Schreurs, John J. Janovy Jr.
John J. Janovy, Jr. Publications
This study was designed to explore the nutritional relationship between Gregarina confusa (Apicomplexa: Eugregarinida) parasites and its coleopteran host, Tribolium destructor, by measuring the cytoplasmic density of gregarines in continuously fed larvae, starved larvae, and larvae refed after starvation. Cultures were maintained in a standard media (whole wheat flour:commercial wheat germ:yeast [30:10:1]). Larvae from control and experimental groups were dissected daily for three days then allowed to feed or starve for an additional three days. On day 6, the remaining experimental larvae were divided and placed into two groups; one group remained starved while larvae from the second group …
The Role Of Phylogeny And Ecology In Experimental Host Specificity: Inisights From A Eugregarine-Host System, Jillian Tikka Detwiler, John J. Janovy Jr.
The Role Of Phylogeny And Ecology In Experimental Host Specificity: Inisights From A Eugregarine-Host System, Jillian Tikka Detwiler, John J. Janovy Jr.
John J. Janovy, Jr. Publications
The degree to which parasites use hosts is fundamental to host–parasite coevolution studies, yet difficult to assess and interpret in an evolutionary manner. Previous assessments of parasitism in eugregarine–host systems suggest high degrees of host specificity to particular host stages and host species; however, rarely have the evolutionary constraints on host specificity been studied experimentally. A series of experimental infections were conducted to determine the extent of host stadium specificity (larval vs. adult stage) and host specificity among 6 tenebrionid host species and 5 eugregarine parasite species. Eugregarines from all host species infected both the larva and adult stages of …
New And Emended Descriptions Of Gregarines From Flour Beetles (Tribolium Spp. And Palorus Subdepressus: Coleoptera, Tenebrionidae), John J. Janovy Jr., Jillian Tikka Detwiler, Samana Schwank, Matthew G. Bolek, Alaine Knipes, Gabriel J. Langford
New And Emended Descriptions Of Gregarines From Flour Beetles (Tribolium Spp. And Palorus Subdepressus: Coleoptera, Tenebrionidae), John J. Janovy Jr., Jillian Tikka Detwiler, Samana Schwank, Matthew G. Bolek, Alaine Knipes, Gabriel J. Langford
John J. Janovy, Jr. Publications
The following new gregarine taxa are described from larvae of flour beetles (Coleoptera: Tenebrionidae): Awrygregarina billmani, n. gen., n. sp., from Tribolium brevicornis; Gregarina cloptoni, n. sp., from Tribolium freemani; Gregarina confusa, n. sp., from Tribolilum confusum; and Gregarina palori, n. sp., from Palorus subdepressus. In addition, the description of Gregarina minuta Ishii, 1914, from Tribolium castaneum, is emended. Scanning electron micrograph studies of these species’ oocysts reveal differences in surface architecture. The Gregarina species have oocysts with longitudinal ridges, visible with SEM, whereas Awrygregarina billmani oocysts have fine circumferential striations; …
Gregarina Niphandrodes (Eugregarinorida: Septatorina): Oocyst Surface Architecture, John J. Janovy Jr., Matthew G. Bolek, Jillian Tikka Detwiler, Samana Schwank, Alaine Knipes, Gabriel J. Langford
Gregarina Niphandrodes (Eugregarinorida: Septatorina): Oocyst Surface Architecture, John J. Janovy Jr., Matthew G. Bolek, Jillian Tikka Detwiler, Samana Schwank, Alaine Knipes, Gabriel J. Langford
John J. Janovy, Jr. Publications
The surface architecture of oocysts produced by Gregarina niphandrodes (Eugregarinorida) from Tenebrio molitor,/i> adults (Coleoptera: Tenebrionidae) as revealed by scanning electron microscopy is reported. Gametocysts were allowed to dehisce on 15-mm, round cover glasses; the cover glasses with their oocysts chains were then mounted on stubs without further processing, and sputter-coated with 20-nm gold-palladium. Scanning electron microscopy was performed at 10-15 kV with a Hitachi 3000N SEM. Oocysts retained their characteristic shapes as reported in the original species description but showed longitudinal ridges of relatively uniform height, width, and spacing, in separate fields on either side of a central equatorial …
Evolutionary Avenues For, And Constraints On, The Transmission Of Frog Lung Flukes (Haematoloechus Spp.) In Dragonfly Second Intermediate Hosts, Matthew G. Bolek, John J. Janovy Jr.
Evolutionary Avenues For, And Constraints On, The Transmission Of Frog Lung Flukes (Haematoloechus Spp.) In Dragonfly Second Intermediate Hosts, Matthew G. Bolek, John J. Janovy Jr.
John J. Janovy, Jr. Publications
Metacercariae survival patterns and their distribution in second intermediate odonate hosts were examined for four species of frog lung flukes. Surveys of aquatic larvae and recently emerged teneral dragonflies and damselflies indicated that prevalence and mean abundance of Haematoloechus spp. metacercariae were significantly lower in teneral dragonflies than larval dragonflies, while there was no significant difference in prevalence or mean abundance of Haematoloechus spp. metacercariae among larval and teneral damselflies. Experimental infections of dragonflies indicated that metacercariae of Haematoloechus coloradensis and Haematoloechus complexus were located in the head, thorax, and branchial basket of dragonflies, whereas metacercariae of Haematoloechus longiplexus and …
Small Frogs Get Their Worms First: The Role Of Nonodonate Arthropods In The Recruitment Of Haematoloechus Coloradensis And Haematoloechus Complexus In Newly Metamorphosed Northern Leopard Frogs, Rana Pipiens, And Woodhouse's Toads, Bufo Woodhousii, Matthew G. Bolek, John J. Janovy Jr.
Small Frogs Get Their Worms First: The Role Of Nonodonate Arthropods In The Recruitment Of Haematoloechus Coloradensis And Haematoloechus Complexus In Newly Metamorphosed Northern Leopard Frogs, Rana Pipiens, And Woodhouse's Toads, Bufo Woodhousii, Matthew G. Bolek, John J. Janovy Jr.
John J. Janovy, Jr. Publications
Studies on the life cycles and epizootiology of North American frog lung flukes indicate that most species utilize odonates as second intermediate hosts; adult frogs become infected by ingesting odonate intermediate hosts. Newly metamorphosed frogs are rarely infected with these parasites, predominantly because they are gape-limited predators that cannot feed on large intermediate hosts such as dragonflies. We examined the role of the frog diet and potential intermediate hosts in the recruitment of the frog lung fluke, Haematoloechus coloradensis, to metamorphosed northern leopard frogs (Rana pipiens), Woodhouse’s toads (Bufo woodhousii), and bullfrogs (Rana catesbeiana …
A New Species Of Myxidium (Myxosporea: Myxidiidae), From The Western Chorus Frog, Pseudacris Triseriata Triseriata, And Blanchard's Cricket Frog, Acris Crepitans Blanchardi (Hylidae), From Eastern Nebraska: Morphology, Phylogeny, And Critical Comments On Amphibian Myxidium Taxonomy, Miloslav Jirků, Matthew G. Bolek, Christopher M. Whipps, John J. Janovy Jr., Mike L. Kent, David Modrý
A New Species Of Myxidium (Myxosporea: Myxidiidae), From The Western Chorus Frog, Pseudacris Triseriata Triseriata, And Blanchard's Cricket Frog, Acris Crepitans Blanchardi (Hylidae), From Eastern Nebraska: Morphology, Phylogeny, And Critical Comments On Amphibian Myxidium Taxonomy, Miloslav Jirků, Matthew G. Bolek, Christopher M. Whipps, John J. Janovy Jr., Mike L. Kent, David Modrý
John J. Janovy, Jr. Publications
During March 2001-April 2004, 164 adult anurans of 6 species (47 Rana blairi, 35 Rana catesbeiana, 31 Hyla chrysoscelis, 31 Pseudacris triseriata triseriata, 11 Bufo woodhousii, and 9 Acris crepitans blanchardi) from Pawnee Lake, Lancaster County, Nebraska, were surveyed for myxozoan parasites. Of these, 20 of 31 (65%) P. triseriata triseriata and 1 of 9 (11%) A. crepitans blanchardi were infected with a new species of Myxidium. Myxidium melleni n. sp. (Myxosporea) is described from the gallbladder of the western chorus frog, P. triseriata triseriata (Hylidae). This is the second species of Myxidium …
Observations On Myiasis By The Calliphorids, Bufolucilia Silvarum And Bufolucilia Elongata, In Wood Frogs, Rana Sylvatica, From Southeastern Wisconsin, Matthew G. Bolek, John J. Janovy Jr.
Observations On Myiasis By The Calliphorids, Bufolucilia Silvarum And Bufolucilia Elongata, In Wood Frogs, Rana Sylvatica, From Southeastern Wisconsin, Matthew G. Bolek, John J. Janovy Jr.
John J. Janovy, Jr. Publications
Larvae of certain species of blowflies (Calliphoridae) can cause myiasis in frogs and toads, but there are few reports from North American amphibians. Of these, most are from toads (bufonids). In this study, we observe primary myiasis in a population of juvenile wood frogs, Rana sylvatica, collected on August 22-23, 2003, from southeastern Wisconsin and compare our observations with previous studies on myiasis from toads. Two (5%) of 39 frogs were infected by the blow fly Bufolucilia silvarum, with an intensity of 28 and 31, whereas 1 (2.5%) of 39 frogs was infected by the blow fly Bufolucilia …
Review Of Parasites And Diseases Of Wild Birds In Florida By D. J. Forrester And M. G. Spalding; University Press Of Florida, 2003, John J. Janovy Jr.
Review Of Parasites And Diseases Of Wild Birds In Florida By D. J. Forrester And M. G. Spalding; University Press Of Florida, 2003, John J. Janovy Jr.
John J. Janovy, Jr. Publications
Review of Parasites and Diseases of Wild Birds in Florida by D. J. Forrester and M. G. Spalding, publsihed by the University Press of Florida, 2003; ISBN: 0-8130-2560-5.
Life Cycle And Paratenesis Of American Gordiids (Nematomorpha: Gordiida), Ben Hanelt, John J. Janovy Jr.
Life Cycle And Paratenesis Of American Gordiids (Nematomorpha: Gordiida), Ben Hanelt, John J. Janovy Jr.
John J. Janovy, Jr. Publications
To complete their life cycle, gordiids must make a transition from aquatic to terrestrial environments. However, epibenthic aquatic larvae and their terrestrial definitive hosts do not overlap in habitat. This has led many investigators to suggest that infections are acquired through the ingestion of insects, which become infected as aquatic larvae with gordiid cysts and subsequently carry gordiids to land. This proposed life cycle was experimentally tested using three common American species of gordiids: Gordius robustus, Paragordius varius, and Chordodes morgani. Cysts of all three species survived the metamorphosis of Tanytarsus sp., a midge. Subsequent infection trials of …
Acceptance Of The Clark P. Read Mentor Award: The Teague Self Lessons, John J. Janovy Jr.
Acceptance Of The Clark P. Read Mentor Award: The Teague Self Lessons, John J. Janovy Jr.
John J. Janovy, Jr. Publications
The transcript of John J. Janovy Jr.'s speech upon acceptance of the American Society of Parasitologists' Clark P. Read Mentor Award, 2003.
Observations On The Life History And Descriptions Of Coccidia (Apicomplexa) From The Western Chorus Frog, Pseudacris Triseriata Triseriata, From Eastern Nebraska, Matthew G. Bolek, John J. Janovy Jr., Armando R. Irizarry-Rovira
Observations On The Life History And Descriptions Of Coccidia (Apicomplexa) From The Western Chorus Frog, Pseudacris Triseriata Triseriata, From Eastern Nebraska, Matthew G. Bolek, John J. Janovy Jr., Armando R. Irizarry-Rovira
John J. Janovy, Jr. Publications
Two hundred and twenty-four anurans of 6 species (47 adults and 16 tadpoles of Rana blairi, 35 R. catesbeiana, 31 Hyla chrysoscelis, 30 adults and 46 tadpoles of Pseudacris triseriata triseriata, 11 Bufo woodhousii, and 8 Acris crepitans) from Pawnee Lake, Lancaster County, Nebraska, were surveyed for coccidian parasites during March 2001 to May 2002. Of these, 23 of 30 (77%) adults and four of 46 (9%) tadpoles of P. t. triseriata shed oocysts of Isospora cogginsi n. sp. Oocysts of I. cogginsi were ovoid, 19.3 × 15.1 (18-23 × 11-20) μm, with a …
Phyllodistomum Funduli N. Sp. (Trematoda: Gorgoderidae) From Fundulus Sciadicus Cope From Cedar Creek In Western Nebraska, Jaclyn Helt, John J. Janvoy Jr., John Ubelaker
Phyllodistomum Funduli N. Sp. (Trematoda: Gorgoderidae) From Fundulus Sciadicus Cope From Cedar Creek In Western Nebraska, Jaclyn Helt, John J. Janvoy Jr., John Ubelaker
John J. Janovy, Jr. Publications
Phyllodistomum funduli n. sp. is described from the urinary bladder and ureters of the Plains topminnow, Fundulus sciadicus, from Cedar Creek in Keith County, Nebraska (41°11.18'N, 101°21.77'W). Phyllodistomum funduli differs from most other Phyllodistomum species reported in possessing an oral sucker that is larger than the acetabulum. Currently, 7 other species of Phyllodistomum have been reported to possess this trait. A comparison of P. funduli with these 7 other species indicates that P. funduli is a distinct species, lacking notches, posterior body folds, caudal projections, or cephalic glands found in some congeners. There is no published report on parasites …
Host Specificity Among Ancyrocephalinae (Monogenoidea) Of Nebraska Sunfish, Megan R. Collins, John J. Janovy Jr.
Host Specificity Among Ancyrocephalinae (Monogenoidea) Of Nebraska Sunfish, Megan R. Collins, John J. Janovy Jr.
John J. Janovy, Jr. Publications
This study addressed the problem of local patterns of host specificity among Ancyrocephalinae (Monogenoidea) on bass and sunfish species, when the hosts occur in different species combinations in separate ponds. One hundred fifty-three fish of the Centrarchidae, from four study sites in Nebraska, were collected. Host species included bluegill (Lepomis macrochirus), green sunfish (L. cyanellus), largemouth bass (Micropterus salmoides), black crappie (Pomoxis nigromaculatus), white crappie (P. annularis), and rock bass (Ambloplites rupestris). These fish occurred in different species combinations, depending on the pond sampled. Results indicated that several …
Concurrent Infections And The Community Ecology Of Helminth Parasites, John J. Janovy Jr.
Concurrent Infections And The Community Ecology Of Helminth Parasites, John J. Janovy Jr.
John J. Janovy, Jr. Publications
A literature review of the topic of concurrent infections and the community ecology of helminth parasites.
Morphometric Analysis Of Nonadult Characters Of Common Species Of American Gordiids (Nematomorpha: Gordioidea), Ben Hanelt, John J. Janovy Jr.
Morphometric Analysis Of Nonadult Characters Of Common Species Of American Gordiids (Nematomorpha: Gordioidea), Ben Hanelt, John J. Janovy Jr.
John J. Janovy, Jr. Publications
The nonadult stages, egg strings, eggs, larvae, and cysts of Gordius robustus, Paragordius varius, and Chordodes morgani are described morphometrically. The goal was to document the differences between species and to evaluate the usefulness of morphometrics in species identification. In concert, multivariate analysis of variance (MANOVA) and univariate analysis of variance (ANOVA, a posteriori contrasts) statistical tests demonstrated that each species is morphometrically distinguishable from all others. Additionally, discriminant function analysis indicated that postseptum length, pseudointestine length, and stylet width were the most important variables in the discrimination of species based on larval characters. Finally, differences in oviposition behaviors …
Physid Snails As Sentinels Of Freshwater Nematomorphs, Ben Hanelt, L. E. Grother, John J. Janovy Jr.
Physid Snails As Sentinels Of Freshwater Nematomorphs, Ben Hanelt, L. E. Grother, John J. Janovy Jr.
John J. Janovy, Jr. Publications
Freshwater nematomorphs, or gordiids, are parasitic as larvae, but free-living in aquatic environments as adults. Studies based on the collection of adults have reported gordiids to be widespread, but discontinuous in distribution. However, a relatively short adult life span and unknown life history make the detection of adults difficult. An alternative approach to investigate gordiid distribution is to use cysts. Of all paratenic hosts, snails were chosen because they lacked internal defense reactions to the cysts and become easily infected. Here, it is reported that the occurrence of gordiids on the basis of the cyst stage is much more common …
Epimerite-Host Epithelium Relationships Among Eugregarines Parasitizing The Damselflies Enallagma Civile And Ischnura Verticalis, Tamara J. Percival Cook, John J. Janovy Jr., Richard E. Clopton
Epimerite-Host Epithelium Relationships Among Eugregarines Parasitizing The Damselflies Enallagma Civile And Ischnura Verticalis, Tamara J. Percival Cook, John J. Janovy Jr., Richard E. Clopton
John J. Janovy, Jr. Publications
The host-parasite interface between two species of damselflies and four species of eugregarines was examined at the ultrastructural level. Nubenocephalus nebraskensis organisms attached to the host midgut epithelium by means of a sucker-like protomerite; the space between the epicytic folds and host epithelium was filled with electron-dense material interpreted to be adhesive in nature. Actinocephalus carrilynnae organisms attached by means of the epimerite, which had no epicytic folds, and by the fluted stalk with characteristic epicytic folds; host cell and parasite membranes appeared fused at some places on the epimerite. Hoplorhynchus acanthatholius organisms attached by means of an ovoid epimerite …
The Response Of Gregarina Niphandrodes (Apicomplexa: Eugregarinida: Septatina) To Host Starvation In Tenebrio Molitor (Coleoptera: Tenebrionidae) Adults, Jennifer E. Schawang, John J. Janovy Jr.
The Response Of Gregarina Niphandrodes (Apicomplexa: Eugregarinida: Septatina) To Host Starvation In Tenebrio Molitor (Coleoptera: Tenebrionidae) Adults, Jennifer E. Schawang, John J. Janovy Jr.
John J. Janovy, Jr. Publications
Numerous studies of host starvation have emphasized pathological effects of parasites on their insect host, but little attention has been focused on the effects of host starvation on the parasites. This study addressed the possibility that parasite life-cycle events could be manipulated by withholding food from the host. The system used was Gregarina niphandrodes (Apicomplexa: Eugregarinida) in Tenebrio molitor (Coleoptera: Tenebrionidae) adults. Gregarine gametocyst formation and shedding ceased after one day in starved beetles but continued in fed controls. There were no statistically significant differences between total lengths of associated (3 of 5 trials) or unassociated (5 of 5 trials) …
Parasite Community Structure In Pimephales Promelas (Pisces: Cyprinidae) From Two Converging Streams, M. A. Weichman, John A. Janovy Jr.
Parasite Community Structure In Pimephales Promelas (Pisces: Cyprinidae) From Two Converging Streams, M. A. Weichman, John A. Janovy Jr.
John J. Janovy, Jr. Publications
Parasites of the fathead minnow, Pimephales promelas, were examined in fish collected from Elk Creek (40.88534°N, 96.83366°W) and West Oak Creek (40.90821°N, 96.81432°W), Lancaster County, Nebraska. These two streams are part of the Salt Valley watershed and flow together approximately 2 km downstream from the collection sites to form Oak Creek. This study examined the extent to which the two tributaries constitute a continuous habitat with respect to fish hosts. The parasite community included Trichodina sp., Myxobolus sp., Dactylogyrus simplex, D. bychowskyi, and D. pectenatus (all on gills); Gyrodactylus hoffmani (gill and body surface); Posthodiplostomum sp. (neascus, body …
Host Specificity In Metamera Sillasenorum, N. Sp., A Gregarine Parasite Of The Leech Helobdella Triserialis With Notes On Transmission Dynamics, Megan R. Wise De Valdez, John J. Janovy Jr., John C. Wise
Host Specificity In Metamera Sillasenorum, N. Sp., A Gregarine Parasite Of The Leech Helobdella Triserialis With Notes On Transmission Dynamics, Megan R. Wise De Valdez, John J. Janovy Jr., John C. Wise
John J. Janovy, Jr. Publications
Eugregarines of the suborder Septatorina are apicomplexan parasites that are found mainly in arthropods. Some exceptions are species in the Metameridae that contains the only 5 septate gregarines recorded from annelids. The type genus is Metamera Duke, 1910 with two species, Metamera schubergi Duke, 1910, in European Glossiphonia complanata, and Metamera reynoldsi Jones, 1943, from North American G. complanata. Over the summers of 1995-1998, in Keith County, Nebraska, septate gregarines were found in the glossiphoniid leech Helobdella triserialis. The gregarines were determined to be a new species of Metamera, herein named Metamera sillasenorum. Measurements of size …
Review Of The Avian Brood Parasites: Deception At The Nest By Paul A. Johnsgard; Oxford University Press, 1997, John J. Janovy Jr.
Review Of The Avian Brood Parasites: Deception At The Nest By Paul A. Johnsgard; Oxford University Press, 1997, John J. Janovy Jr.
John J. Janovy, Jr. Publications
Review of The Avian Brood Parasites: Deception at the Nest by Paul A. Johnsgard, published by Oxford University Press, 1997, ISBN: 0-19-511042-0.
The Life Cycle Of A Horsehair Worm, Gordius Robustus (Nematomorpha: Gordioidea), Ben Hanelt, John J. Janovy Jr.
The Life Cycle Of A Horsehair Worm, Gordius Robustus (Nematomorpha: Gordioidea), Ben Hanelt, John J. Janovy Jr.
John J. Janovy, Jr. Publications
Aspects of the life cycle of the nematomorph Gordius robustus were investigated. Gordius robustus larvae fed to Tenebrio molitor (Coleoptera: Tenebrionidae) readily penetrated and subsequently encysted in the posterior portion of the midgut wall. Parasite development was then arrested in each infected beetle. Upon feeding these cysts to laboratory-reared Gryllus firmus. worm larvae developed to adults in the cricket hemocoel. In an additional experiment, G. robustus larvae fed to G. firmus did not develop to adults. These findings are in contrast to other studies that found direct infection to be an alternative mode of infection. This experiment is the …
Evolutionary Constraints On Population Structure: The Parasites Of Fundulus Zebrinus (Pisces: Cyprinodontidae) In The South Platte River Of Nebraska, John J. Janovy Jr., Scott D. Snyder, Richard E. Clopton
Evolutionary Constraints On Population Structure: The Parasites Of Fundulus Zebrinus (Pisces: Cyprinodontidae) In The South Platte River Of Nebraska, John J. Janovy Jr., Scott D. Snyder, Richard E. Clopton
John J. Janovy, Jr. Publications
Population and community descriptor values (parasites per host, prevalence per parasite species, variance/mean ratios, species density, and diversity indices) for the 7-species parasite community of 61 relatively homogeneous samples of Fundulus zebrinus (Pisces: Cyprinodontidae) in the South Platte River of Nebraska, U.S.A., taken over a 14-yr period, are reported. South Platte River streamflow fluctuates over two orders of magnitude on several time scales-monthly, annually, and over multiple year wet-dry cycles. Relatively homogeneous sampling of a single host species with several parasite species provided a system that allowed assessment of the contribution of evolved parasite life cycles to population structure in …