Microhabitat Segregation of the Threatened Spotted Darter (Etheostoma maculatum) and Closely Related Orangefin Darter (E. bellum)

1993 ◽  
Vol 50 (5) ◽  
pp. 1084-1091 ◽  
Author(s):  
Richard K. Kessler ◽  
James H. Thorp
Keyword(s):  
Threatened Species ◽  
Narrow Range ◽  
Microhabitat Use ◽  
Sympatric Populations ◽  
High Discharge ◽  
Substrate Use ◽  
Quantitative Sampling ◽  
Morphological Differences ◽  
Species Specific ◽  
Microhabitat Segregation

We examined differences in microhabitat use in sympatric populations of the closely related spotted darter (Etheostoma maculatum) and orangefin darter (E. bellum) (subgenus Nothonotus). Sample plots and underwater observations were employed to assess patterns of microhabitat use by both species. Quantitative sampling using a prepositioned electrofishing sampler demonstrated that species segregated by microhabitats. Etheostoma maculatum occupied areas of greater depth and larger, more diverse substrate sizes than E. bellum in July and October of 1991. Underwater observations also revealed species-specific differences in substrate use. Etheostoma maculatum was observed mostly under rocks whereas E. bellum was more general in substrate use. The narrow range of microhabitat use by E. maculatum may contribute to its status as a threatened species in Kentucky. During July 1991, an unusually high discharge month that year, males of both species occupied microhabitats of significantly higher velocities and larger substrate sizes than females. Our data suggest that opportunities for coexistence between these closely related darters are enhanced by microhabitat partitioning which is linked to behavioral and morphological differences.

scholarly journals Resurrection of the Butterfly-winged Comber, Serranus papilionaceus Valenciennes, 1832 (Teleostei, Serranidae) and its phylogenetic position within genus Serranus

ZooKeys ◽  
2021 ◽  
Vol 1017 ◽  
pp. 111-126
Author(s):  
Adriana Vella ◽  
Noel Vella ◽  
Carolina Acosta-Díaz
Keyword(s):  
Conservation Status ◽  
Valid Species ◽  
Phylogenetic Position ◽  
Mitochondrial Coi ◽  
Interspecific Divergence ◽  
Population Conservation ◽  
Status Assessment ◽  
Morphological Differences ◽  
Species Specific ◽  
High Level

The family Serranidae is represented by 92 genera and 579 valid species, with the genus Serranus Cuvier, 1816, containing 30 species. In this study, specimens of Butterfly-winged Comber, Serranus papilionaceus Valenciennes, 1832, were collected from the Canary Islands and compared morphologically and genetically to Painted Comber, Serranus scriba (Linnaeus, 1758), from the Mediterranean Sea. Morphological differences, especially in the colour banding pattern, were corroborated by genetic differences in mitochondrial (COI and ND2) and nuclear (Rhod and PTR) markers. The mitochondrial DNA markers revealed a high level of divergence and no shared haplotypes between the two species (interspecific divergence: COI 4.31%; ND2 8.68%), and a phylogenetic analysis showed that these two species are closely related sister species sharing common ancestry. This study is therefore offering to resurrect S. papilionaceus Valenciennes, 1832 as a valid species increasing the number of eastern Atlantic Serranus species to 11. This should direct new species-specific research, including its population conservation status assessment across its distribution.

scholarly journals Why and how might genetic and phylogenetic diversity be reflected in the identification of key biodiversity areas?

2015 ◽  
Vol 370 (1662) ◽  
pp. 20140019 ◽  
Author(s):  
T. M. Brooks ◽  
A. Cuttelod ◽  
D. P. Faith ◽  
J. Garcia-Moreno ◽  
P. Langhammer ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Threatened Species ◽  
Phylogenetic Diversity ◽  
Species Population ◽  
Threatened Taxa ◽  
Conservation Actions ◽  
Ecosystem Diversity ◽  
Species Specific ◽  
A Site ◽  
Specific Conservation

‘Key biodiversity areas' are defined as sites contributing significantly to the global persistence of biodiversity. The identification of these sites builds from existing approaches based on measures of species and ecosystem diversity and process. Here, we therefore build from the work of Sgró et al. (2011 Evol. Appl. 4 , 326–337. ( doi:10.1111/j.1752-4571.2010.00157.x )) to extend a framework for how components of genetic diversity might be considered in the identification of key biodiversity areas. We make three recommendations to inform the ongoing process of consolidating a key biodiversity areas standard: (i) thresholds for the threatened species criterion currently consider a site's share of a threatened species' population; expand these to include the proportion of the species' genetic diversity unique to a site; (ii) expand criterion for ‘threatened species' to consider ‘threatened taxa’ and (iii) expand the centre of endemism criterion to identify as key biodiversity areas those sites holding a threshold proportion of the compositional or phylogenetic diversity of species (within a taxonomic group) whose restricted ranges collectively define a centre of endemism. We also recommend consideration of occurrence of EDGE species (i.e. threatened phylogenetic diversity) in key biodiversity areas to prioritize species-specific conservation actions among sites.

The effect of cover and food on space use by wintering Song Sparrows and Field Sparrows

1997 ◽  
Vol 75 (10) ◽  
pp. 1636-1641 ◽  
Author(s):  
Christopher W. Beck ◽  
Bryan D. Watts
Keyword(s):  
Predation Risk ◽  
Positive Response ◽  
Distribution Patterns ◽  
Microhabitat Use ◽  
Vegetative Cover ◽  
Song Sparrows ◽  
Trade Offs ◽  
Resource Requirements ◽  
Woody Cover ◽  
Species Specific

The distribution of birds among microhabitats may reflect species-specific resource requirements. Both food availability and predation risk have been shown to influence patterns of microhabitat use by sparrows during winter. We investigated the influence of vegetative cover and food on microhabitat use using a 2 × 2 factorial design. Both woody cover and food were manipulated at the plot level. The presence of screening cover (weed stems) was manipulated within plots. Sparrows showed a positive response to the presence of both cover and food. Within plots, sparrows selected areas with screening cover. The distribution of birds between areas with and without screening cover was influenced by the presence of woody cover and food. Conversely, the presence of screening cover reduced the influence of woody cover on the distribution of birds within patches. Song Sparrows (Melospiza melodia) and Field Sparrows (Spizella pusilla) differed in their response to treatments both within and across plots, suggesting that trade-offs between foraging and predation risk may be important in the structuring of winter sparrow assemblages. Additionally, screening cover appears to moderate predation risk and therefore to affect distribution patterns.

scholarly journals Microhabitat Use Affects Brain Size and Structure in Intertidal Gobies

2015 ◽  
Vol 85 (2) ◽  
pp. 107-116 ◽  
Author(s):  
Gemma E. White ◽  
Culum Brown
Keyword(s):  
Spatial Learning ◽  
Brain Size ◽  
Microhabitat Use ◽  
Rocky Shores ◽  
Rock Pool ◽  
Environmental Complexity ◽  
Learning Abilities ◽  
Trade Offs ◽  
Species Specific ◽  
Dorsal Medulla

The ecological cognition hypothesis poses that the brains and behaviours of individuals are largely shaped by the environments in which they live and the associated challenges they must overcome during their lives. Here we examine the effect of environmental complexity on relative brain size in 4 species of intertidal gobies from differing habitats. Two species were rock pool specialists that lived on spatially complex rocky shores, while the remainder lived on dynamic, but structurally simple, sandy shores. We found that rock pool-dwelling species had relatively larger brains and telencephalons in particular, while sand-dwelling species had a larger optic tectum and hypothalamus. In general, it appears that various fish species trade off neural investment in specific brain lobes depending on the environment in which they live. Our previous research suggests that rock pool species have greater spatial learning abilities, enabling them to navigate their spatially complex environment, which may account for their enlarged telencephalon, while sand-dwelling species likely have a reduced need for spatial learning, due to their spatially simple habitat, and a greater need for visual acuity. The dorsal medulla and cerebellum size was unaffected by the habitat in which the fish lived, but there were differences between species indicative of species-specific trade-offs in neural investment.

scholarly journals Notes on the extended distribution of two threatened species of Strobilanthes Blume (Acanthaceae) in Kerala, India

2017 ◽  
Vol 9 (5) ◽  
pp. 10236
Author(s):  
E.J. Josekutty ◽  
P. Biju ◽  
Jomy Augustine
Keyword(s):  
Threatened Species ◽  
Western Ghats ◽  
Narrow Range ◽  
Conservation Status ◽  
Restricted Distribution

The extended distributional record of two threatened species of Strobilanthes namely S. canarica and S. campanulata in Kerala is provided.  They exhibit narrow range of habitats in Western Ghats with highly restricted distribution.  Notes on taxonomy, phenology, distribution and conservation status are also given.

scholarly journals Description of two new species of the genus Cacopsylla Ossiannilsson, 1970 (Hemiptera, Psylloidea) from northern Fennoscandia recognized by morphology, cytogenetic characters and COI barcode sequence

2019 ◽  
Vol 13 (4) ◽  
pp. 367-382 ◽  
Author(s):  
Christina Nokkala ◽  
Valentina G. Kuznetsova ◽  
Veikko Rinne ◽  
Seppo Nokkala
Keyword(s):  
Tree Line ◽  
Nucleotide Substitutions ◽  
Sympatric Populations ◽  
Bisexual Species ◽  
Vaccinium Uliginosum ◽  
Parthenogenetic Species ◽  
Ledum Palustre ◽  
Northern Fennoscandia ◽  
Morphological Differences ◽  
Female Genital

Based on chromosomal, molecular and morphological analyses, two new Cacopsylla Ossiannilsson, 1970 species are described, C. lapponica S. Nokkala & Ch. Nokkala, sp. nov. and C. borealis S. Nokkala et Ch. Nokkala, sp. nov. (Hemiptera, Psylloidea). C. lapponica is a rare bisexual alpine species living on Vaccinium uliginosum Linnaeus, 1753 above tree line on northern hills, where it forms sympatric populations with C. myrtilli W. Wagner, 1947. So far, the species has been found in northern Finland, Utsjoki and Kilpisjärvi, and in northern Sweden, Abisko. The chromosome number in males is 2n = 12+X(0), characteristic of psyllids. The species is easily distinguished from C. myrtilli by its conspicuously smaller size mainly due to difference in wing size. Additional morphological differences are found in the length of antennae, female genital plates and male parameres. C. borealis, in turn, is a relatively common apomictic parthenogenetic species with 5n = 60 + XXXXX living on the same host plant, Ledum palustre Linnaeus, 1753, as C. ledi (Flor, 1861) and occasionally forming sympatric populations with it. No males have been recorded in C. borealis. Its distribution range reaches at least from northern Fennoscandia to Lake Baikal in the East. C. borealis can be distinguished from C. ledi by differences in the length and width of antennae, dark brown markings on the wing and female terminal structures. For molecular analysis, a 638 bp fragment of the mitochondrial COI gene was sequenced. C. lapponica differs from the cohabitating C. myrtilli by 20 fixed nucleotide substitutions (uncor rected p-distance 3.13 %), while C. borealis differs from C. ledi by 21 fixed nucleotide substitutions (uncorrected p-distance 3.29 %). Molecular phylogeny construction (ML and BI) reveals two highly divergent clades, one comprising two bisexual species, C. lapponica and C. fraudatrix Labina & Kuznetsova, 2012, and the other clade comprising the parthenogenetic species C. borealis, C. myrtilli, and C. ledi. Within this clade, C. borealis is more closely associated with C. myrtilli than with C. ledi.

scholarly journals Unrestricted gene flow between two subspecies of translocated brushtail possums (Trichosurus vulpecula) in Aotearoa New Zealand

2021 ◽  
Author(s):  
Nimeshika Pattabiraman ◽  
Mary Morgan-Richards ◽  
Ralph Powlesland ◽  
Steven A. Trewick
Keyword(s):  
New Zealand ◽  
Trichosurus Vulpecula ◽  
Mitochondrial Dna Control Region ◽  
Aotearoa New Zealand ◽  
Nuclear Microsatellite ◽  
Morphological Differences ◽  
Mating Unit ◽  
Species Specific ◽  
Phenotypic Forms ◽  
Major Haplogroups

AbstractTwo lineages of brushtail possums (Trichosurus vulpecula) were historically introduced to Aotearoa New Zealand, and these two subspecies have different phenotypic forms. Despite over 100 years of potential interbreeding, they appear to retain morphological differences, which may indicate reproductive isolation. We examined this using population samples from a confined landscape and scored each specimen for phenotype using a number of fur colour traits. This resulted in a bimodal trait distribution expected for segregated grey and black lineages. We also sought evidence for genetic partitioning based on spatial and temporal effects. Genetic structure and rates of genetic mixing were determined using seven neutral, species-specific nuclear microsatellite markers and mitochondrial DNA control region sequence. Genotype analyses indicated high levels of variation and mtDNA sequences formed two major haplogroups. Pairwise tests for population differentiation of these markers found no evidence of subdivision, indicating that these brushtail possums behave as a single randomly mating unit. Despite maintenance of two main colour phenotypes with relatively few intermediates, previous inference of assortative mating and anecdotes of distinct races, our data indicate that New Zealand brushtail possums can freely interbreed, and that in some locations they have formed completely mixed populations where neutral genetic markers are unrelated to phenotype. This has implications for effective pest management towards eradication.

scholarly journals Parasite-mediated microhabitat segregation between congeneric hosts

2018 ◽  
Vol 14 (2) ◽  
pp. 20170671 ◽  
Author(s):  
Olwyn C. Friesen ◽  
Robert Poulin ◽  
Clément Lagrue
Keyword(s):  
Parasitic Infection ◽  
Habitat Segregation ◽  
Microhabitat Use ◽  
Extended Phenotype ◽  
Trematode Parasite ◽  
Host Distribution ◽  
Set Up ◽  
Rocky Habitats ◽  
Microhabitat Segregation

Parasite-mediated competition can shape community structure and host distribution. If two species compete for resources, parasites may indirectly change the outcome of competition. We tested the role of a trematode parasite in mediating microhabitat use by congeneric isopods Austridotea annectens and Austridotea lacustris . Although both isopods share resources, they rarely co-occur in the same discrete microhabitats. We set up mesocosms with and without competition and/or parasites to examine the role of parasites in host distribution and habitat segregation. Austridotea annectens showed a clear preference for one microhabitat type regardless of competition or parasitic infection. By contrast, A. lacustris showed little habitat selection in the absence of competition, but favoured sandy habitats in the presence of uninfected A. annectens and rocky habitats when competing with infected A. annectens . Our results suggest that parasites in one species affect the distribution of another species, and mediate competition between these species. We demonstrated the impacts of a parasite on the microhabitat use of its host's competitor. This also represents an example of a super-extended phenotype, where a parasite affects the phenotype of a non-host.

scholarly journals Sintopy of two Tropidurus lizard species (Squamata: Tropiduridae) in a rocky Cerrado habitat in Central Brazil

2004 ◽  
Vol 64 (4) ◽  
pp. 775-786 ◽  
Author(s):  
R. G. Faria ◽  
A. F. B. Araujo
Keyword(s):  
Sympatric Species ◽  
Microhabitat Use ◽  
Lizard Species ◽  
Cerrado Vegetation ◽  
Central Brazil ◽  
Heterogeneous Landscapes ◽  
Interspecific Territoriality ◽  
Morphological Differences ◽  
Rocky Habitats ◽  
Ecological Differences

We studied the ecology of Tropidurus itambere and T. oreadicus that occur syntopically in rocky habitats of Cerrado vegetation in central Brazil during the dry season (April to September 2000). The two species are ecologically similar, but somewhat differentiated in vertical microhabitat use. The two species preferred rocky surface microhabitat. Both species demonstrated a unimodal activity pattern, with a peak between 10 and 15 h. Their diets were similar in composition and prey size. The most frequent item used by both species was ants, whereas the most important preys volumetrically were termites and ants. Small morphological differences observed between the two Tropidurus species could explain minor microhabitat divergence: T. itambere is slightly smaller, heavier, and more robust, and uses lower perches. T. oreadicus is larger, lankier, with longer extremities (tail, fore- and hindlegs), and uses a larger vertical microhabitat range. These ecological differences are slight, when compared with those observed between sympatric species of Tropidurus in spatially more heterogeneous landscapes. Considering the slight ecomorphological divergence between the two Tropidurus species and their high abundance in outcrops, we suggest that interspecific territoriality is the mechanism of coexistence.

Characterization of Waterhemp (Amaranthus tuberculatus) × Smooth Pigweed (A. hybridus) F1Hybrids

2006 ◽  
Vol 20 (1) ◽  
pp. 14-22 ◽  
Author(s):  
Federico Trucco ◽  
Tatiana Tatum ◽  
Kenneth R. Robertson ◽  
A. Lane Rayburn ◽  
Patrick J. Tranel
Keyword(s):  
Dna Content ◽  
Parental Species ◽  
Hybrid Sterility ◽  
Field Surveys ◽  
Amaranthus Tuberculatus ◽  
Cytogenetic Analyses ◽  
Morphological Differences ◽  
Species Specific ◽  
Natural Settings ◽  
Smooth Pigweed

In the state of Illinois, waterhemp and smooth pigweed are among the worst agricultural weeds. Previous research shows high potential for hybridization between these two species. However, the actual occurrence of hybrids in natural settings is still uncertain. Morphological similarity between hybrids and waterhemp makes field surveys of hybrids difficult to conduct. The main purpose of this study was to characterize the morphology of waterhemp × smooth pigweed F1hybrids, emphasizing evaluation of characters that may allow for hybrid discrimination in fieldAmaranthuscommunities. Concurrently, the study characterized hybrid reproductive fitness, chromosome number, and DNA content. To accomplish this, hybrids were obtained from field crosses. A species-specific polymorphism in theALSgene was used to verify hybrid identity. Significant differences (α = 0.05) between hybrids and individuals of the parental species were observed for five staminate and five carpellate characters. Of these, five characters differentiated hybrids from waterhemp. However, clustering analyses using these characters indicated that morphological differences were not reliable enough, by themselves, for unambiguous hybrid identification. Also, hybrid homoploidy (2n= 32) with respect to parental species excluded chromosome counts in hybridity determinations. However, DNA content analysis may be used for such purpose. Hybrids had an average of 1.21 pg of DNA per 2C nucleus, a value intermediate to that of parental species. Hybrids produced 3.3 or 0.7% the seed output of parental and sibling waterhemp individuals, respectively. Percent micropollen in hybrids was 95-times greater than in parental species. Hybrid sterility appears to be the most reliable feature for hybrid discrimination when conducting field surveys. However, molecular and cytogenetic analyses as employed in this study may be desired for ultimate identity corroboration.

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