Size overlap in intertidal decapod communities along the chilean coast

The intertidal crustaceans on the Chilean coast are characterized by high diversity and niche specialization. The present study applied a size overlap null model for intertidal decapod communities at four different sites on the Chilean coast. The results revealed that there is a size overlap for the four sites, though body size is significantly different for each location. This means that the reported species would share their ecological niches. The results agree with the first classic environmental descriptions for Chilean intertidal decapods at a local scale and support the observations for similar species on the southern Pacific and southern Atlantic coasts.

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New and interesting species of the genera Galumna and Pergalumna (Acari, Oribatida, Galumnidae) from the Montagne d'Ambre National Park, Madagascar

Acarologia ◽

10.24349/acarologia/20204357 ◽

2020 ◽

Vol 60 (1) ◽

pp. 64-74

Author(s):

Sergey G. Ermilov ◽

Josef Starý

Keyword(s):

New Species ◽

Body Size ◽

National Park ◽

Similar Species ◽

Two New Species ◽

Ethiopian Region ◽

First Time ◽

Interesting Species ◽

Median Pore

This work includes taxonomic and faunistic data on galumnid mites (Oribatida, Galumnidae) belonging to the genera Galumna and Pergalumna collected from the Montagne d'Ambre National Park, North Madagascar. Two new species are described: Galumna sandormahunkai n. sp. differs from its closest species, Galumna sphagni by the larger body size, the presence of strongly protruding rostrum, lanceolate, pointed apically bothridial setae, the direction of lamellar lines, and the absence of median pore; Pergalumna janosbaloghi n. sp. differs from the most similar species, Pergalumna aegra, by the smaller body size and the presence of long lamellar setae and elongate, distinctly or slightly triangular porose areas Aa. Galumna granalata and Pergalumna amamiensis are recorded in the Ethiopian region for the first time; Pergalumna conspicua and P. frater are recorded in Madagascar for the first time.

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Four new species of the superfamily Galumnoidea (Acari: Oribatida) from Ecuador

Zootaxa ◽

10.11646/zootaxa.3481.1.2 ◽

2012 ◽

Vol 3481 (1) ◽

pp. 27 ◽

Cited By ~ 2

Author(s):

SERGEY G. ERMILOV ◽

STANISLAV KALÚZ

Keyword(s):

New Species ◽

Body Size ◽

Distal Part ◽

Oribatid Mite ◽

Mite Species ◽

Similar Species ◽

Pore Length ◽

Smooth Body ◽

First Time ◽

Oribatid Mite Species

Four new oribatid mite species of the superfamily Galumnoidea, Pergalumna paradecoratissima sp. nov., Pergalumnaparalongisetosa sp. nov., Pergalumna ecuadorensis sp. nov. and Galumnopsis lanceosensilla sp. nov., are described fromEcuador. The genus Galumnopsis is recorded for the first time for the Ecuador. Pergalumna paradecoratissima sp. nov.is very similar in having the combination of foveolate prodorsum, striate notogaster, setiform sensilli, interlamellar setaeshorter than lamellar and rostral setae, absence of anterior notogastral margin and three pairs of notogastral porose areas,to Pergalumna decoratissima Pérez-Íñigo & Baggio, 1986 from Brazil, however it differs from the latter by morphologyof rostrum, body size, surface of anal plates and length of epimeral setae. Pergalumna paralongisetosa sp. nov. is verysimilar in having the combination of setiform sensilli, long prodorsal setae, absence of anterior notogastral margin, threepairs of notogastral porose areas and long adanal setae ad 1 and ad 2 to Pergalumna longisetosa Balogh, 1960 from CentralAfrica, however it differs from the latter by body size, lengths of sensilli and interlamellar setae, absence of medial pore,length of epimeral setae. Pergalumna ecuadorensis sp. nov. can be distinguished from all similar species by having theround rostrum, setiform sensilli, long and setiform prodorsal setae, absence of anterior notogastral margin, smooth bodysurface and three pairs of oval notogastral porose areas, and by the very long interlamellar setae. Galumnopsis lanceosen-silla sp. nov. can be distinguished from all similar species (with smooth body surface) by the morphology of sensilli which are lanceolate, with tooth in distal part.

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Testing biodiversity theory using species richness of reef-building corals across a depth gradient

Biology Letters ◽

10.1098/rsbl.2019.0493 ◽

2019 ◽

Vol 15 (10) ◽

pp. 20190493 ◽

Cited By ~ 2

Author(s):

T. Edward Roberts ◽

Sally A. Keith ◽

Carsten Rahbek ◽

Tom C. L. Bridge ◽

M. Julian Caley ◽

...

Keyword(s):

Species Richness ◽

Large Scale ◽

Coral Species ◽

Environmental Gradients ◽

Abiotic Factors ◽

Empirical Support ◽

Null Model ◽

Local Scale ◽

Small Scale ◽

Energy Availability

Natural environmental gradients encompass systematic variation in abiotic factors that can be exploited to test competing explanations of biodiversity patterns. The species–energy (SE) hypothesis attempts to explain species richness gradients as a function of energy availability. However, limited empirical support for SE is often attributed to idiosyncratic, local-scale processes distorting the underlying SE relationship. Meanwhile, studies are also often confounded by factors such as sampling biases, dispersal boundaries and unclear definitions of energy availability. Here, we used spatially structured observations of 8460 colonies of photo-symbiotic reef-building corals and a null-model to test whether energy can explain observed coral species richness over depth. Species richness was left-skewed, hump-shaped and unrelated to energy availability. While local-scale processes were evident, their influence on species richness was insufficient to reconcile observations with model predictions. Therefore, energy availability, either in isolation or in combination with local deterministic processes, was unable to explain coral species richness across depth. Our results demonstrate that local-scale processes do not necessarily explain deviations in species richness from theoretical models, and that the use of idiosyncratic small-scale factors to explain large-scale ecological patterns requires the utmost caution.

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Perch Selection by Three Cooccurring Species ofCelithemis(Odonata: Libellulidae): Testing for a Competitive Hierarchy among Similar Species

Psyche A Journal of Entomology ◽

10.1155/2016/9028105 ◽

2016 ◽

Vol 2016 ◽

pp. 1-8 ◽

Cited By ~ 3

Author(s):

Wade B. Worthen ◽

Parker H. Morrow

Keyword(s):

Body Size ◽

Niche Partitioning ◽

Open Water ◽

The Other ◽

Similar Species ◽

Male Body ◽

Size Dependent ◽

Anatomical Characters ◽

Relative Abundances ◽

Imagej Software

In many communities of perching dragonflies (Odonata: Libellulidae), a size-dependent competitive hierarchy creates a positive relationship between male body size and perch height. We tested for this pattern among three similar-sized species:Celithemis elisa,C. fasciata, andC. ornata.Males were caught and photographed from May to July 2015 at Ashmore Heritage Preserve, Greenville County, SC, USA, and perch heights and perch distance to open water were measured. Five indices of body size were measured with ImageJ software: abdomen length, forewing length, hindwing length, area of forewing, and area of hindwing.Celithemis fasciatawas significantly larger than the other two species for all five anatomical characters and used perches that were significantly taller and closer to open water than the other species, though these differences changed over the summer. Aggressive interactions between and within species were tallied and compared to expected distributions based on mean relative abundances derived from hourly abundance counts. Patterns of interspecific aggression were also consistent with a size-dependent hierarchy: the largeC. fasciatawas attacked less frequently, and the smallC. ornatamore frequently, than predicted by their relative abundances. We conclude that even small differences in body size may contribute to niche partitioning in perch selection.

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New smallest specimen of the pterosaurPteranodonand ontogenetic niches in pterosaurs

Journal of Paleontology ◽

10.1017/jpa.2017.84 ◽

2017 ◽

Vol 92 (2) ◽

pp. 254-271 ◽

Cited By ~ 6

Author(s):

S. Christopher Bennett

Keyword(s):

Body Size ◽

Parental Care ◽

Large Body ◽

Taxonomic Diversity ◽

Ecological Niches ◽

Adult Size ◽

Niobrara Formation ◽

Large Body Size ◽

Juvenile Specimen

AbstractA new juvenile specimen ofPteranodonfrom the Smoky Hill Chalk Member of the Niobrara Formation of western Kansas had an estimated wingspan in life of 1.76 m, ~45% smaller than the smallest previously known specimens, but does not differ in morphology from larger specimens. Its presence indicates that juveniles were capable of flying long distances, so it falsifies the interpretation ofPteranodonas growing rapidly to adult size under parental care before flying. Instead juveniles were precocial, growing more slowly to adult size while flying and feeding independently for several years before going to sea. Because juveniles are otherwise unknown in the Smoky Hill Chalk Member, they must have occupied different environments and ecological niches than adults; thusPteranodonexhibited ontogenetic niches. Evidence is presented that most other pterosaurs (e.g.,Rhamphorhynchus,Pterodactylus,Anhanguera) also exhibited various ontogenetic niches, which, along with their large body size, suggests that pterosaur taxonomic diversity was rather low, like that of crocodilians.

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My niche: individual spatial niche specialization affects within- and between-species interactions

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2019.2211 ◽

2020 ◽

Vol 287 (1918) ◽

pp. 20192211 ◽

Cited By ~ 5

Author(s):

Annika Schirmer ◽

Julia Hoffmann ◽

Jana A. Eccard ◽

Melanie Dammhahn

Keyword(s):

Species Interactions ◽

Community Dynamics ◽

Species Coexistence ◽

Myodes Glareolus ◽

Ecological Niches ◽

Species Variation ◽

Interaction Patterns ◽

Spatial Interactions ◽

Interindividual Differences ◽

Niche Specialization

Intraspecific trait variation is an important determinant of fundamental ecological interactions. Many of these interactions are mediated by behaviour. Therefore, interindividual differences in behaviour should contribute to individual niche specialization. Comparable with variation in morphological traits, behavioural differentiation between individuals should limit similarity among competitors and thus act as a mechanism maintaining within-species variation in ecological niches and facilitating species coexistence. Here, we aimed to test whether interindividual differences in boldness covary with spatial interactions within and between two ecologically similar, co-occurring rodent species ( Myodes glareolus , Apodemus agrarius ). In five subpopulations in northeast Germany, we quantified individual differences in boldness via repeated standardized tests and spatial interaction patterns via capture–mark–recapture ( n = 126) and automated VHF telemetry ( n = 36). We found that boldness varied with space use in both species. Individuals of the same population occupied different spatial niches, which resulted in non-random patterns of within- and between-species spatial interactions. Behavioural types mainly differed in the relative importance of intra- versus interspecific competition. Within-species variation along this competition gradient could contribute to maintaining individual niche specialization. Moreover, behavioural differentiation between individuals limits similarity among competitors, which might facilitate the coexistence of functionally equivalent species and, thus, affect community dynamics and local biodiversity.

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High niche overlap between two successfully coexisting pairs of Lake Malawi cichlid fishes

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f09-023 ◽

2009 ◽

Vol 66 (4) ◽

pp. 579-588 ◽

Cited By ~ 27

Author(s):

Christopher H. Martin ◽

Martin J. Genner

Keyword(s):

Resource Availability ◽

Niche Overlap ◽

Lake Malawi ◽

Resource Scarcity ◽

Ecological Niches ◽

Similar Species ◽

Dietary Overlap ◽

Resource Abundance ◽

Species Pairs ◽

Foraging Rate

Many species in high-diversity assemblages appear to coexist in similar ecological niches. It has been proposed that interspecific resource partitioning in these assemblages may only occur during periods of resource scarcity. We tested this hypothesis by measuring resource abundance, dietary overlap, foraging rate, and territoriality in a Lake Malawi rock cichlid assemblage over a period of 1 year. Our study examined two pairs of morphologically similar species, with each pair comprising one native species and one invader species that has successfully established after being translocated from another region of the lake. All four species changed their diet and foraging rate in response to seasonal variation in resource abundance. However, dietary overlap within both species pairs remained high in all seasons and was not influenced by resource availability. Similarly, territoriality did not decline during periods of low resource availability, suggesting no decrease in the strength of interspecific competition. These data suggest that these species pairs are successfully coexisting despite substantial niche overlap during resource scarcity. Thus, the coexistence of species within this radiation may not depend on the evolution of divergent resource use patterns.

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A new species in the genus Alopecosa Simon, 1885 from Korea (Araneae: Lycosidae)

Zootaxa ◽

10.11646/zootaxa.397.1.1 ◽

2004 ◽

Vol 397 (1) ◽

pp. 1 ◽

Cited By ~ 3

Author(s):

JUNGSUN YOO ◽

JOOPIL KIM ◽

HOZUMI TANAKA

Keyword(s):

Electron Microscope ◽

New Species ◽

Body Size ◽

Scanning Electron Microscope ◽

Morphological Characteristics ◽

The Body ◽

Similar Species ◽

A New Species ◽

Scanning Electron

Alopecosa volubilis n. sp. is described from Korea and is differentiated from other species in Alopecosa Simon, 1885 by morphological characteristics, such as three retromarginal teeth of chelicera, smaller body size, and the presence of a distinct tip of the median apophysis. The pedipalpal sclerites and somatic characters of two similar species, A. moriutii Tanaka, 1985 and A. hokkaidensis Tanaka, 1985, are compared with those of the new species. An illustration of the body and scanning electron microscope (SEM) pictures of the pedipalpal organ are provided.

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Rates of ecological divergence and body size evolution are correlated with species diversification in scaly tree ferns

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2016.1098 ◽

2016 ◽

Vol 283 (1834) ◽

pp. 20161098 ◽

Cited By ~ 12

Author(s):

Santiago Ramírez-Barahona ◽

Josué Barrera-Redondo ◽

Luis E. Eguiarte

Keyword(s):

Species Richness ◽

Body Size ◽

Ecological Niche ◽

Morphological Evolution ◽

Ecological Niches ◽

Species Diversification ◽

Tree Ferns ◽

Size Evolution ◽

Body Sizes ◽

Body Size Evolution

Variation in species richness across regions and between different groups of organisms is a major feature of evolution. Several factors have been proposed to explain these differences, including heterogeneity in the rates of species diversification and the age of clades. It has been frequently assumed that rapid rates of diversification are coupled to high rates of ecological and morphological evolution, leading to a prediction that remains poorly explored for most species: the positive association between ecological niche divergence, morphological evolution and species diversification. We combined a time-calibrated phylogeny with distribution, ecological and body size data for scaly tree ferns (Cyatheaceae) to test whether rates of species diversification are predicted by the rates at which clades have evolved distinct ecological niches and body sizes. We found that rates of species diversification are positively correlated with rates of ecological and morphological evolution, with rapidly diversifying clades also showing rapidly evolving ecological niches and body sizes. Our results show that rapid diversification of scaly tree ferns is associated with the evolution of species with comparable morphologies that diversified into similar, yet distinct, environments. This suggests parallel evolutionary pathways opening in different tropical regions whenever ecological and geographical opportunities arise. Accordingly, rates of ecological niche and body size evolution are relevant to explain the current patterns of species richness in this ‘ancient’ fern lineage across the tropics.

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