Morphology and microhabitat use in stream fish

1995 ◽  
Vol 52 (7) ◽  
pp. 1487-1498 ◽  
Author(s):  
Brian M. Wood ◽  
Mark B. Bain
Keyword(s):  
Regression Analysis ◽  
Fish Species ◽  
Morphological Variation ◽  
Stream Fish ◽  
Microhabitat Use ◽  
Stream Fishes ◽  
Species Comparison ◽  
Body Morphology ◽  
Specialist Species ◽  
Morphological Differences

Microhabitat use and body morphology were compared among 15 warmwater stream fishes from the Alabama River (Alabama, U.S.A.) watershed. Morphological variation among separate populations of a species was detected in 14 of the 15 species, indicating that populations should be separated in analyses among species. Comparison of morphological variation between microhabitat generalist and specialist species suggested that all species may vary in morphology relative to their environment. Regression analysis showed that within two families, Cyprinidae and Percidae, morphology was related to specific microhabitat variables. In the Centrarchidae, morphology was not related to any microhabitat variables. Morphological differences among the species occurred along gradients that were similar to gradients of habitat utilization, indicating that within a family, species widely separated in microhabitat use were morphologically different and species using similar microhabitats were similar in morphology. Our results suggest that patterns of morphological variation correspond to properties of the available habitat for warmwater stream fish species.

Spawning phenology and habitat use in a Great Plains, USA, stream fish assemblage: an occupancy estimation approach

2010 ◽  
Vol 67 (12) ◽  
pp. 1942-1956 ◽  
Author(s):  
Jeffrey A. Falke ◽  
Kurt D. Fausch ◽  
Kevin R. Bestgen ◽  
Larissa L. Bailey
Keyword(s):  
Habitat Use ◽  
Great Plains ◽  
Fish Species ◽  
Fish Assemblages ◽  
Fish Larvae ◽  
Estimation Methods ◽  
Stream Fish ◽  
Stream Fishes ◽  
Occupancy Estimation ◽  
Multiple Samples

Knowledge of basic life-history attributes, paired with unbiased estimates of species distribution, is critical for the effective conservation of sensitive fish species. We quantified the spawning phenology, habitat use, and detectability for larvae of an assemblage of threatened Great Plains, USA, stream fishes using new occupancy estimation methods. Spawning by six Great Plains fish species occurred from April through July, and was likely initiated by changes in water temperature and photoperiod. Habitat size and type were important factors influencing the occupancy of larvae in spawning habitats. Detectability of larvae differed among species and over time, and was influenced by habitat depth and fish size. Our models indicated that multiple samples from individual habitats within a season are needed to adequately detect and predict occupancy by stream fish larvae. Conservation efforts for imperiled Great Plains fish assemblages should focus on sustaining flows that maintain a sufficient density and size of habitats needed for successful spawning and recruitment. The occupancy estimation and modeling methods employed here will be useful in developing comprehensive, unbiased programs to monitor the reproductive success of Great Plains stream fishes.

A reassessment of Dioon merolae (Zamiaceae) leads to the description of Dioon salas-moralesae, a new cycad species from Southeastern Oaxaca, Mexico

Phytotaxa ◽  
2021 ◽  
Vol 528 (2) ◽  
pp. 93-110
Author(s):  
JOSÉ SAID GUTIÉRREZ-ORTEGA ◽  
MIGUEL ANGEL PÉREZ-FARRERA ◽  
JEFFREY CHEMNICK ◽  
TIMOTHY J. GREGORY
Keyword(s):  
New Species ◽  
Morphological Variation ◽  
Related Species ◽  
Statistical Tests ◽  
Distinct Species ◽  
Closely Related Species ◽  
Morphometric Variation ◽  
Isthmus Of Tehuantepec ◽  
Morphological Differences ◽  
Recent Evaluation

The cycad genus Dioon comprises 17 species from Mexico and Honduras, all of them delimited based on their morphological variation and geographic distribution. A recent evaluation of the biological variation among Dioon populations from Oaxaca and Chiapas, Mexico, demonstrated that the concept of the species Dioon merolae actually consists of three lineages that should be recognized as different taxa. One lineage was already described as Dioon oaxacensis, leaving the concept of Dioon merolae comprising two lineages distributed on both sides of the Isthmus of Tehuantepec. However, there are conspicuous morphological differences between these two lineages. Here, we tested whether such a differentiation within the concept of Dioon merolae merits the differentiation of two different taxa. We evaluated the qualitative and morphometric variation among populations belonging to the Dioon merolae lineages, and compared it with the closely related species Dioon oaxacensis. Morphological observations and statistical tests demonstrated that the populations of southeastern Oaxaca, traditionally considered as part of Dioon merolae, represent a distinct species that we described as Dioon salas-moralesae. Identifying the diagnostic characters of this new species helps enable an understanding of the criteria that should be considered to delineate the boundaries between other cycad species.

AN ANALYSIS OF INTERSPECIFIC AND INTRASPECIFIC MORPHOLOGICAL DIFFERENCES IN TWO CLOSELY RELATED SPECIES OF AMBLYSEIUS BERLESE USING METHODS OF NUMERICAL TAXONOMY (ACARINA: PHYTOSEHDAE)

1977 ◽  
Vol 109 (12) ◽  
pp. 1605-1618 ◽  
Author(s):  
D.A. Chant ◽  
R.I.C. Hansell ◽  
H.J. Rowell
Keyword(s):  
Host Plant ◽  
Morphological Variation ◽  
Related Species ◽  
Numerical Taxonomy ◽  
Valid Species ◽  
Closely Related Species ◽  
Multivariate Tests ◽  
Taxonomic Methods ◽  
Morphological Differences ◽  
Intraspecific Morphological Variation

AbstractMorphological variation between two closely related species in the genus Amblyseius Berlese was examined by numerical taxonomic methods. Multivariate tests indicated that A. canadensis Chant and Hansell and A. novaescotiae (Chant) represent two separate and distinct morphological groups. This supports their taxonomic retention as valid species. Intraspecific morphological variation was also examined and found to be correlated with climatic and host plant variables.

Effects of Urbanization on Stream Ecosystems

2005 ◽  
Keyword(s):  
Species Richness ◽  
Fish Species ◽  
Endemic Species ◽  
Largemouth Bass ◽  
Fish Assemblage ◽  
Life Histories ◽  
Fish Assemblages ◽  
Habitat Alterations ◽  
Intensity Index ◽  
Specialist Species

<em>Abstract.</em>—We examined fish assemblage responses to urban intensity gradients in two contrasting metropolitan areas: Birmingham, Alabama (BIR) and Boston, Massachusetts (BOS). Urbanization was quantified by using an urban intensity index (UII) that included multiple stream buffers and basin land uses, human population density, and road density variables. We evaluated fish assemblage responses by using species richness metrics and detrended correspondence analyses (DCA). Fish species richness metrics included total fish species richness, and percentages of endemic species richness, alien species, and fluvial specialist species. Fish species richness decreased significantly with increasing urbanization in BIR (<em>r </em>= –0.82, <EM>P </EM>= 0.001) and BOS (<em>r </em>= –0.48, <EM>P </EM>= 0.008). Percentages of endemic species richness decreased significantly with increasing urbanization only in BIR (<em>r </em>= – 0.71, <EM>P </EM>= 0.001), whereas percentages of fluvial specialist species decreased significantly with increasing urbanization only in BOS (<em>r </em>= –0.56, <EM>P </EM>= 0.002). Our DCA results for BIR indicate that highly urbanized fish assemblages are composed primarily of largescale stoneroller <em>Campostoma oligolepis</em>, largemouth bass <em>Micropterus salmoides</em>, and creek chub <em>Semotilus atromaculatus</em>, whereas the highly urbanized fish assemblages in BOS are dominated by yellow perch <em>Perca flavescens</em>, bluegill <em>Lepomis macrochirus</em>, yellow bullhead <em>Ameiurus natalis</em>, largemouth bass, pumpkinseed <em>L. gibbosus</em>, brown bullhead <em>A. nebulosus</em>, and redfin pickerel <em>Esox americanus</em>. Differences in fish assemblage responses to urbanization between the two areas appear to be related to differences in nutrient enrichment, habitat alterations, and invasive species. Because species richness can increase or decrease with increasing urbanization, a general response model is not applicable. Instead, response models based on species’ life histories, behavior, and autecologies offer greater potential for understanding fish assemblage responses to urbanization.

Community Ecology of Stream Fishes: Concepts, Approaches, and Techniques

2010 ◽  
Keyword(s):  
Climate Change ◽  
Fish Species ◽  
Species Distribution ◽  
General Circulation ◽  
Greenhouse Gas Emission ◽  
General Circulation Models ◽  
Consensus Method ◽  
Stream Fish ◽  
Emission Scenarios ◽  
Distribution Models

<em>Abstract</em>.—Stream fish are expected to be influenced by climate change as they are ectothermic animals living in lotic systems. Using fish presence–absence records in 1,110 stream sites across France, our study aimed at (1) modeling current and future distributions of 35 stream fish species, (2) using an ensemble forecasting approach (i.e., several general circulation models [GCM] × greenhouse gas emission scenarios [GES] × statistical species distribution models [SDM] combinations) to quantify the variability in the future fish species distribution due to each component, and (3) assessing the potential impacts of climate change on fish species distribution and assemblage structure by using a consensus method that accounted for the variability in future projections.

Community Ecology of Stream Fishes: Concepts, Approaches, and Techniques

2010 ◽  
Keyword(s):  
Great Plains ◽  
Life Histories ◽  
Environmental Heterogeneity ◽  
Environmental Variability ◽  
Spatial Scales ◽  
Stream Fish ◽  
Metapopulation Dynamics ◽  
Stream Fishes ◽  
Spatial And Temporal Scales ◽  
Trade Offs

<em>Abstract</em>.—Stream fishes carry out their life histories across broad spatial and temporal scales, leading to spatially structured populations. Therefore, incorporating metapopulation dynamics into models of stream fish populations may improve our ability to understand mechanisms regulating them. First, we reviewed empirical research on metapopulation dynamics in the stream fish ecology literature and found 31 papers that used the metapopulation framework. The majority of papers applied no specific metapopulation model, or included space only implicitly. Although parameterization of spatially realistic models is challenging, we suggest that stream fish ecologists should incorporate space into models and recognize that metapopulation types may change across scales. Second, we considered metacommunity theory, which addresses how trade-offs among dispersal, environmental heterogeneity, and biotic interactions structure communities across spatial scales. There are no explicit tests of metacommunity theory using stream fishes to date, so we used data from our research in a Great Plains stream to test the utility of these paradigms. We found that this plains fish metacommunity was structured mainly by spatial factors related to dispersal opportunity and, to a lesser extent, by environmental heterogeneity. Currently, metacommunity models are more heuristic than predictive. Therefore, we propose that future stream fish metacommunity research should focus on developing testable hypotheses that incorporate stream fish life history attributes, and seasonal environmental variability, across spatial scales. This emerging body of research is likely to be valuable not only for basic stream fish ecological research, but also multispecies conservation and management.

Genetic variation in Trithuria inconspicua and T. filamentosa (Hydatellaceae): a new subspecies and a hypothesis of apomixis arising within a predominantly selfing lineage

2019 ◽  
Author(s):  
Rob D. Smissen ◽  
Kerry A. Ford ◽  
Paul D. Champion ◽  
Peter B. Heenan
Keyword(s):  
Genetic Variation ◽  
New Zealand ◽  
Morphological Variation ◽  
Genetic Distances ◽  
Herbarium Specimens ◽  
Minimum Evolution ◽  
The North ◽  
Genetic Groups ◽  
Morphological Differences ◽  
High Level

While examining herbarium specimens of Trithuria inconspicua Cheeseman, we observed differences in the stigmatic hairs among plants from New Zealand’s North and South Islands. This motivated us to assess genetic and morphological variation within this species and its sister T. filamentosa Rodway from Tasmania. Samples were collected from lakes in the three disjunct geographic areas where the two species occur. Genetic variation in both species was assessed with simple sequence-repeat (SSR, microsatellite) markers and analyses of genetic distances. We also compared the morphology of northern and southern New Zealand T. inconspicua using fresh material. Samples of each species clustered together in a minimum evolution tree built from genetic distances. Trithuria filamentosa had more genetic diversity than did T. inconspicua. Within T. inconspicua, plants from lakes in the North Island and the South Island formed discrete genetic groups diagnosable by subtle morphological differences. Low levels of heterozygosity in both species are consistent with a high level of selfing, as suggested for other co-sexual Trithuria species, but unusual for a putative apomict. On the basis of genetic and morphological variation, we propose recognition of the northern New Zealand and southern New Zealand lineages of T. inconspicua at subspecies rank.

scholarly journals Ichthyo-faunal diversity of Morang district, Nepal

Our Nature ◽  
2017 ◽  
Vol 15 (1-2) ◽  
pp. 55-67
Author(s):  
Bharat Raj Subba ◽  
Nelson Pokharel ◽  
Manish Raj Pandey
Keyword(s):  
Fish Species ◽  
Water Bodies ◽  
Paddy Fields ◽  
Stream Fishes ◽  
Faunal Diversity ◽  
One Year ◽  
Schizothorax Plagiostomus

The present paper attempts to report a total of 118 fish species spread over 11 orders, 26 families and 64 genera inhabited indifferent water bodies viz, rivers, reservoirs, streams, ponds, lakes, canals, ditches, paddy fields of Morang district, collected during a one-year survey. The order Cypriniformes is the richest one among 11 orders that comprises 59 species followed by Siluriformes having 31 and Perciformes with 19 representatives, respectively. Orders Anguilliformes, Osteoglossiformes, Beloniformes, Cyprinodontiformes, Synbranchiformes and Tetraodontiformes have only one representative. Olyra longicaudata is the new report from Morang district and the second report from Nepal. Besides this, other hill-stream fishes viz., Pseudecheneis sulcatus, Schizothorax plagiostomus, Schistura savona and Neolissochilus hexagonolepis recorded during the survey, also have not been previously reported from this district.

Sign in / Sign up

Export Citation Format

Share Document