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1.
The damselfish Chromis limbata is native to the Macaronesian Archipelagos (Azores, Madeira and Canaries) and the western coast of Africa between Senegal and Angola. During the austral summers of 2008 and 2009 the species was recorded for the first time in the south‐western Atlantic Ocean around Campeche and Xavier Islands, in Florianópolis, Santa Catarina State, Brazil. Here, the progression of C. limbata in southern Brazilian waters is described using visual counts and genetic surveys and changes in the density of the native congener Chromis multilineata were also investigated. Underwater visual censuses of both Chromis species were carried out from 2009 to 2014. Chromis limbata tissue samples were collected and the mtDNA control region was sequenced and compared with mtDNA haplotypes from the natural range to confirm species identity, compare genetic diversity and to infer connectivity between newly established Brazilian populations. The Brazilian population of C. limbata increased significantly over the past 5 years and the effect on C. multilineata is still an open question, longer time‐series data will be necessary to clarify possible interactions. The molecular analyses confirmed species identity, revealed strong haplotype connectivity among Brazilian study sites and showed a low genetic diversity in Brazil when compared with the native populations, suggesting few individuals started the invasion. Four hypotheses could explain this colonizing event: C. limbata was released by aquarium fish keepers; larvae or juveniles were transported via ship ballast water; the species has rafted alongside oil rigs; they crossed the Atlantic Ocean through normal larval dispersal or naturally rafting alongside drifting objects. The rafting hypotheses are favoured, but all four possibilities are plausible and could have happened in combination. 相似文献
2.
Feeding ecology and resource sharing patterns between Stellifer rastrifer (Jordan, 1889) and S. brasiliensis (Schultz, 1945) (Perciformes: Sciaenidae) along the coasts of Paraná and Santa Catarina,Brazil
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F. A. Frehse M. O. Valduga M. F. M. Corrêa P. C. Pinheiro J. R. S. Vitule 《Zeitschrift fur angewandte Ichthyologie》2015,31(3):479-486
In this study the diet of Stellifer rastrifer and S. brasiliensis were analysed in order to assess the role of resource partitioning between these congeneric, sympatric and abundant species along the coasts of Paraná (25 °55′28″S; 48 °33′35″W) and Santa Catarina (26 °25′55″S; 48 °34′46″W), in southern Brazil. The stomach contents of 240 S. rastrifer specimens (52–195 mm total length) and 167 S. brasiliensis (60–182 mm total length) collected by trawl boat in March of 2006, were analysed to assess the influence of sites, day and night periods as well as the size class in their diet composition. Although crustaceans have been the main resources of both species, S. rastrifer consumed pelagic and epibenthic items, whereas S. brasiliensis also used benthic resources. Results of permanova analysis provided significant evidence for food resource partitioning and confirm the role of feeding changes in the function of morphology (species, P = 0.001), behaviour (day and night, P = 0.024), and ontogeny (size classes, P = 0.001), strategies to reduce competition and to maintain the coexistence of these syntopic species. 相似文献
3.
Climate and weather affect phenological events in a wide range of taxa, and future changes might disrupt ecological interactions. Amphibians are particularly sensitive to climate, but few studies have addressed climatically mediated change in the phenology of closely related species or sexes. Here, we test the hypothesis that changes in spring temperatures result in phenological change among Triturus, and we examine inter‐ and intraspecific differences in response. Coexisting populations of Triturus helveticus and Triturus vulgaris at Llysdinam pond in mid‐Wales (53°12′59″N 3°27′3″W) were monitored using pitfall traps along a drift fence during 1981–1987, and again in 1997–2005. Spring temperature over the same period explained up to 74% of between‐year variability in median arrival date, with a significant advance of 2–5 days with every degree centigrade increase. Changes were greater for males than females of both species, and greater for T. helveticus than T. vulgaris within sexes, resulting in an increasing temporal separation between arrivals of male T. helveticus and all other groups. These data illustrate for the first time how climatic change might have differential effects on sympatric species and on the two sexes. 相似文献
4.
Species with wide distribution, generally show variations in life history characteristics, which can be attributed to environmental causes. In this study, we analyzed the reproductive cycle and reproductive characteristics from three populations (Atlapexco, San Pablo Tetlapayac, and Santa Catarina) of the lizard Sceloporus variabilis from central Mexico. The specific goal of this study was to evaluate life history characteristics such as reproductive period extent, SVL (snout‐vent length) at sexual maturity, clutch size, egg mass and volume, and RCM (relative clutch mass). The San Pablo Tetlapayac population showed a larger clutch size, RCM, egg mass, and a smaller SVL, body mass and reproductive period (January‐September), as well as egg volume than the Atlapexco and Santa Catarina populations. Reproductive cycle and reproductive characteristics were more similar between the Atlapexco and Santa Catarina populations. Differences found in the population of San Pablo Tetlapayac with respect to the Atlapexco and Santa Catarina populations could be attributed to environmental variations where lizard populations occur. Differences in the reproductive period and reproductive characteristics in each population could be the result of both historical (phylogenetic; e.g., reproductive mode) and nonhistorical (environmental; e.g., temperature, food availability) causes. This study showed that populations of the same species are under different selection pressures, and these affect the reproductive characteristics of populations. Our results also indicate that long‐term and targeted studies on predation, use and selection of food, are needed to determine the causes of these variations in populations of S. variabilis. 相似文献
5.
Jamerson Aguiar‐Santos André S. Sampaio Thamires L. Barroso Jorge L. S. Nunes Nivaldo M. Piorski 《Zeitschrift fur angewandte Ichthyologie》2018,34(4):1084-1086
Length‐weight relationship parameters were calculated for six fish species from São Marcos Bay, in Northeast Brazil (the segment between 02°35′55″S and 44°20′58″W; 02°34′53″S and 44°21′48″W; 02º42′25″S and 44º26′46″W). The specimens were caught quarterly from April 2010 to February 2013, using monofilament gillnets (2, 4 and 6 cm between knots) from 100 m to 3,000 m long and 4 m to 6 m high. The present study covers a much wider size range for four species and adds new information for the maximum length of Notarius bonillai. 相似文献
6.
Andre V. F. Faria Nuno T. Martins Ligia M. Ayres-Ostrock Carlos F. D. Gurgel Estela M. Plastino 《Journal of phycology》2023,59(5):1041-1052
Changes in the sea level during the Holocene are regarded as one of the most prevalent drivers of the diversity and distribution of macroalgae in Brazil, influenced by the emergence of the Vitória-Trindade seamount chain (VTC). Gracilariopsis tenuifrons has a wide geographic distribution along the Brazilian coast, from Maranhão state (2°48′64.3" S) to Santa Catarina state (27.5°73′83" S). The knowledge of historical processes affecting diversity may allow the development of conservation strategies in environments against anthropogenic influence. Therefore, knowledge about phylogeography and populational genetic diversity in G. tenuifrons is necessary. Six populations were sampled along the northeastern tropical (Maranhão—MA, Rio Grande do Norte—RN, Alagoas—AL, and Bahia—BA States) and southeastern subtropical (São Paulo “Ubatuba”—SP1 and São Paulo “Itanhaém”—SP2 States) regions along the Brazilian coast. The genetic diversity and structure of G. tenuifrons were inferred using mitochondrial (COI-5P and cox2-3 concatenated) DNA markers. Gracilariopsis tenuifrons populations showed an evident separation between the northeast (from 2°48′64.3" S to 14°18′23" S; 17 haplotypes) and the southeast (from 23°50′14.9" S to 24°20′04.7" S; 10 haplotypes) regions by two mutational steps between them. The main biogeographical barrier to gene flow is located nearby the VTC. The southeast region (São Paulo State) is separated by two subphylogroups (SP1, three haplotypes and SP2, six haplotypes), and Santos Bay (estuary) has been considered a biogeographical barrier between them. The presence of genetic structure and putative barriers to gene flow are in concordance with previous studies reporting biogeographic breaks in the southwest Atlantic Ocean, including the genetic isolation between northeast and southeast regions for red and brown algae in the vicinity of the VTC. 相似文献
7.
Length‐weight and length‐length relationships of thirteen fish species from the lower Jinsha River,southwest China
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K. Shao Y. F. Que M. H. Xiong W. T. Li D. Yu F. Shi 《Zeitschrift fur angewandte Ichthyologie》2018,34(3):774-776
Length‐weight and length‐length relationships were investigated for 13 freshwater fish species from the lower Jinsha River, southwest China (from 101°32′49.63″E; 26°35′38.27″N to 104°37′48.14″E; 28°45′59.55″N). Fish were sampled from five sites during 2014 and 2016, using trap‐nets, gillnets (major mesh size: 2–6 cm), longline and electrofishing. Length‐weight relationships for six and length‐length relationships for 12 species are the first report to FishBase, respectively. Moreover, new maximum length for 11 species are also presented to FishBase in this study. All regressions were highly significant (p < .001), with the coefficient of determination r2 > .950. These information will be helpful for management and conservation in local fishes and fisheries. 相似文献
8.
A female specimen of the slender sunfish Ranzania laevis of 600 mm total length was recorded for the first time from the Red Sea after being stranded on a shallow sandy bay at Hurghada beach (27° 06′ 16″ N; 33° 50′ 01″ E) on 13 May 2012. Ranzania laevis is believed to have migrated from the Indian Ocean as the nearest area where it was found is coastal waters of Oman. 相似文献
9.
Length–weight relationships for Eutropiichthys murius (Hamilton, 1822), Coilia reynaldi Valenciennes, 1848 and Johnius gangeticus Talwar, 1991 from lower stretch of the River Ganga,India
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Subodha K. Karna Raju Baitha Archisman Ray Amit Mondal Himanshu S. Swain Thangjam N. Chanu Mitesh H. Ramteke Ranjan K. Manna Basanta K. Das 《Zeitschrift fur angewandte Ichthyologie》2018,34(5):1251-1252
Length‐weight relationships (LWRs) for three fish species from the River Ganga (India) is presented. Sampling was conducted from the lower stretch of the River Ganga (Patna: 25°36′51.66″N & 85°12′7.02″E to Freserganj: 21°35′40.58″N & 88°15′28.92″E) during April, June and September and December of 2017. Specimens were caught using gill nets (18 nos.; mesh 18–32 mm), and bag nets (3 nos.; mesh 14–22 mm). The values a and b from LWRs ‐were found to be 0.007 and 2.977 for Eutropiichthys murius; 0.003 and 3.001 for Coilia reynaldi; 0.009 and 3.010 for Johnius gangeticus. 相似文献
10.
Length–weight relationships of three fish species from Kerala waters,south‐west coast of India
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《Zeitschrift fur angewandte Ichthyologie》2017,33(6):1308-1309
Length–weight relationships (LWRs) of three fish species: Scomberomorus commerson, Alepes vari, and A. kleinii were estimated from Kerala waters, south‐west coast of India. Fish were captured between June 2016 and June 2017 by various gears such as ring seine (8–26 mm mesh size), trawl (30–40 mm cod end mesh size), hook and line (hook number VI–XII), smaller mesh sized drift gill net (26–90 mm) and larger one (120–170 mm) for bigger size fishes. Fish were collected on weekly basis from Cochin Fisheries Harbour (Lat. 09°56′327″N, Long. 76°15′764″E), Munambam Fisheries Harbour (Lat. 10°10′965″N, Long. 76°10′258″E), Kalamukku (Lat. 09°59′924″N, Long. 76°14′564″E) and Chellanam (Lat. 09°47′950″N, Long. 76°16′551″E). All LWRs were significant with r2 values ranged from 0.944 to 0.996 and b values ranged from 2.722 to 3.021 (p < .001). In addition, this study provides the information on LWRs and new maximum size for Alepes vari and A. kleinii. 相似文献
11.
Length–weight and length–length relationships of eight fish species from river Ganga,India
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R. Baitha S. K. Karna A. Ray T. N. Chanu H. S. Swain M. H. Ramteke S. Bayen R. K. Manna B. K. Das 《Zeitschrift fur angewandte Ichthyologie》2018,34(4):1052-1054
Present study provides length–weight relationships (LWRs) and length–length relationships (LLRs) of eight fish species from river Ganga, India. Specimens were sampled from gill nets (mesh, 22–120 mm), cast nets (mesh, 12–14 mm), and seine nets (mesh, 12 mm) on quarterly basis from September 2016 to September 2017 within the river stretch from Buxar (25°33′43.90″N and 83°56′3.10″E) to Freserganj (21°35′40.58″N and 88°15′28.92″E). The b value ranged from 2.86 (Otolithoides pama) to 3.08 (Polynemus paradiseus), whereas a value ranged from 0.004 (P. paradiseus) to 0.016 (Rita rita). Both relationships (LWRs and LLRs) were found to be highly correlated (p < .001). This study provides first report on LWR for Amblyceps mangois and Osteobrama cotio, whereas new maximum length recorded for Macrognathus pancalus. Furthermore, the estimate of R. rita should be considered as tentative because of the limited size range in the study. 相似文献
12.
Mukti H. Sarma Goutam Gupta Ramaswamy H. Sarma 《Journal of biomolecular structure & dynamics》2013,31(6):1057-1084
Abstract ID NOE 1H NMR spectroscopy at 500 MHz was employed to examine the structure of poly(dA)·poly(dT) in solution. NOE experiments were conducted as a function of presaturation pulse length (50, 30, 20 and 10 msec) and.power (19 and 20 db) to distinguish the primary NOEs from spin diffusion. The 10 msec NOE experiments took 49 hrs and over 55,000 scans for each case and the difference spectra were almost free from diffusion. The spin diffused NOE difference spectra as well as difference NOE spectra in 90% H2O + 10% D2O in which TNH3 was presaturated enabled to make a complete assignment of the base and sugar protons. It is shown that poly(dA) ·poly(dT) melts in a fashion in which single stranded bubbles are formed with increasing temperature. Extremely strong primary NOEs were observed at H2′/H2″ when AH8 and TH6 were presaturated. The observed NOEs at AH2′ and that AH2″ were very similar as were the NOEs at TH2′ and TH2″. The observed NOEs at AH2′ and AH2″when AH8 was presaturated were very similar to those observed at TH2′ and TH2″ when TH6 was presaturated. In addition, presaturation of H1′ of A and T residues resulted in similar NOEs at AH2′/H2″ and TH2′/H2″ region and these NOEs at H2′ and H2″ were distinctly asymmetric as expected in a C2′-endo sugar pucker. There was not a trace of NOE at AH8 and TH6 when AH3′ and TH3′ were presaturated indicating that C3′-endo, × = 30–40° conformation is not valid for this DNA. From these NOE data, chemical shift shielding calculations and stereochemistry based computer modellings, we conclude that poly(dA)·poly(dT) in solution adopts a right- handed B-DNA duplex in which both dA and dT strands are conformationally equivalent with C2′-endo sugar pucker and a glycosyl torsion, ×, of ?73°, the remaining backbone torsion angles being φ′ = 221°, ω′ = 212°, ω = 310°, φ = 149°, ψ = 42°, ψ′ = 139°. The experimental data are in total disagreement with the heteronomous DNA model of Arnott et. al. proposed for the fibrous state. (Arnott, S., Chandrasekaran, R., Hall, I.H., and Puigjaner, L.C., Nucl. Acid Res. 11, 4141, 1983). 相似文献
13.
14.
Length–weight and length–length relationships for two gobiids from the Anzali Wetland,in the southern Caspian Sea basin
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A. Heidari H. Mousavi‐Sabet M. Sattari M. S. Alavi‐Yeganeh K. Abbasi 《Zeitschrift fur angewandte Ichthyologie》2018,34(4):1042-1044
Length–weight (LWR) and length–length (LLR) relationships were estimated for specimens of two gobiid species collected from the Anzali Wetland and its related streams in the southern Caspian Sea basin, in August 2017. These represent the first reports of LWR and LLR data for Rhinogobius cf. similis Gill, 1859 (37°28′13″N, 49°20′33″E; 50 individuals) and Proterorhinus nasalis (De Filippi, 1863) (36°54′10.89″N, 53°48′48.33″E; 30 individuals) from the Wetland. A new maximum length is reported for P. nasalis. The length–weight parameter b for these species ranged a minimum of 2.99 for Rhinogobius cf. similis to a maximum of 3.04 for P. nasalis with regression coefficients (r2) ranging from .95 to .97. All LLRs were highly significant (r2>.96). 相似文献
15.
Maria Laura S. Delapieve Tiago P. Carvalho Roberto E. Reis 《Journal of fish biology》2020,97(6):1748-1769
Epactionotus species are known for inhabiting the rocky-bottom stretches of fast-flowing rivers in a limited geographic area along the Atlantic coast of southern Brazil. These species are endemic to single coastal river drainages (two neighbouring drainages for Epactionotus bilineatus) isolated from each other by the coastal lacustrine environments or the Atlantic Ocean. E. bilineatus is from the Maquiné and Três Forquilhas River basins, both tributaries of the Tramandaí River system, whereas E. itaimbezinho is endemic to the Mampituba River drainage and Epactionotus gracilis to the Araranguá River drainage. Recent fieldwork in the Atlantic coastal drainages of southern Brazil revealed new populations in the Urussanga, Tubarão, d'Una and Biguaçu River drainages. Iterative species delimitation using molecular data (cytochrome c oxidase subunit I) and morphology (morphometrics and meristics) was applied to evaluate species recognition of isolated populations. With regard to new data, the genus was re-diagnosed, the status of Epactionotus species/populations was re-evaluated, formerly described species were supported and population structure was recognized. As for the newly discovered populations, both morphological and molecular data strongly support the population from the Biguaçu River drainage, in Santa Catarina State, as a new species. Molecular data revealed strong per-basin population structure, which may be related to species habitat specificity and low or no dispersal among drainages. 相似文献
16.
Length–weight relationship of selected elasmobranch species from north‐eastern Arabian Sea,India
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Y. Gladston K. V. Akhilesh C. Thakurdas O. P. K. Ravi S. M. Ajina L. Shenoy 《Zeitschrift fur angewandte Ichthyologie》2018,34(3):753-757
Length–weight relationship (LWR) was estimated for 12 elasmobranch species; five shark species, four species of rays and three species of guitar fishes from north‐eastern Arabian Sea, India. Five major landing centres of Maharashtra were selected; Satpati (Lat. 19°43′15″N, Long. 72°42′00″E), Naigaon (Lat. 19°19′32″N, Long. 72°48′54″E), Versova (Lat. 19°08′33″N, Long. 72°48′11″E), New ferry Wharf (Lat. 18°57′29″N Long. 72°51′01″E) and Sassoon dock (Lat. 18°54′42″N, Long. 72°49′33″E). Samples were collected fortnightly during August 2016 to October 2017 from various gears; drift gill nets (Hung length 114–143 m and #100–270 mm) off Satpati coast at 35–50 m depth, dol nets (length 50–65 m and cod end # 30–69 mm) in Naigaon at 38–50 m depth and trawl (length 33–72 m and cod end # 17–32 mm) in Versova, New ferry Wharf and Sassoon dock operated at 20–50 m depth. Multiday fishing was carried out with 2–3 fishing trips in a month, each trip with duration of 7–13 days. Soaking time of gill net and dol net varied from 4 to 8 hr while each trawl haul lasted for 3–4 hr. Length–weight/Disc‐width‐weight relationship showed good fit with r2 values varying from 0.818 to 0.999. In addition to information on LWR, new maximum size for three species of elasmobranchs is reported in this paper. 相似文献
17.
Raju Baitha Archisman Ray Subodha K. Karna Thangjaum N. Chanu Himanshu S. Swain Mitesh H. Ramteke Aprajita Singh Ranjan K. Manna Basanta K. Das 《Zeitschrift fur angewandte Ichthyologie》2018,34(5):1195-1197
Length‐weight relationships (LWRs) for four fish species from the River Ganga (India) is presented. Sampling was conducted in the lower stretch of the river (Buxar: 25°33′43.90″N and 83°56′3.10″E to Freserganj: 21°35′40.58″N and 88°15′28.92″E) on tri‐monthly basis from September 2016 to December 2017. Specimens were caught in gill nets (mesh, 18–68 mm), cast nets (mesh, 12–14 mm), seine nets (mesh, 12–14 mm) and various traditional traps those were put over night and lifted in early morning. Total length and wet body weight of fish were measured to the nearest 0.1 cm and 0.01 g by a digital caliper and electronic balance respectively. From LWRs, the estimated b values were found to be 2.88 (Pisodonophis boro) to 3.17 (Gagata sexualis) whereas a value ranged from 0.001 (Pisodonophis boro) to 0.009 (Botia lohachata). As per FishBase, the species Gagata sexualis and Botia lohachata had new TLmax reported for LWR estimation. 相似文献
18.
The complex piezoelectric constant (d = d′ ? id″), elastic constant (c = c′ + ic″), and dielectric constant (ε = ε′ ? iε″) were measured at a frequency of 10 Hz over the temperature range from ?150 to 50°C and for a range of hydration up to 0.26 g/g for decalcified bone and up to 0.084 g/g for bone. For decalcified bone, ε′ and ε″ increased with increasing hydration with a deflection at the critical hydration hc = 0.08 g/g;d′ at ?150°C increased below hc but decreased above hc with increasing hydration; c′ increased below ?60°C but decreased above ?60°C with increasing hydration; and the peak temperatures of ε″, d″, and c″ below ?50°C agree with each other and decreased with increasing hydration with a deflection at hc. For bone, similar hydration and temperature dependences were observed for ε and c. However, the dependence of d on hydration and temperature was different from that of decalcified bone, reflecting a two-phase structure consisting of collagen fibers and mineral hydroxyapatite. The critical hydration for bone was 0.04 g/g. 相似文献
19.
Length–weight relationships of two endemic species of Alburnoides nicolausi (Bogutskaya & Coad, 2009) and Alburnus zagrosensis (Coad, 2009) in Houzian River,Lorestan Province,Iran
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A. Rezamand M. Pouladi A. Qadermarzi R. Ghorbani M. Mohammadi Movahed 《Zeitschrift fur angewandte Ichthyologie》2018,34(3):758-759
This investigation prepares the length–weight relationships (LWRs) of two fish species, including Alburnoides nicolausi (Bogutskaya & Coad, 2009) and Alburnus zagrosensis (Coad, 2009) from Houzian River (latitude 33°22′15.20″ to 33°21′31.57″N; longitude 49°44′39.66″ to 49°44′17.67″E), Lorestan province, Iran. Fish specimens were collected monthly using seine net with 5 mm (Stretched) mesh size between April to September 2017. The LWRs for fish species were W = 0.0059L3.405 (male) and W = 0.0053L3.494 (female) for A. nicolausi, W = 0.0035L3.341 (male) and W = 0.003L3.387 (female) for A. zagrosensis, respectively. The highest value of r2 was .931 for male of A. zagrosensis and lowest value was .964 for male of A. nicolausi. 相似文献
20.
Eduardo G. Gonçalves 《Nordic Journal of Botany》2011,29(4):385-390
Two new species of Philodendron– Araceae (Philodendron bernardopazii E. G. Gonç. and Philodendron ricardoi E. G. Gonç.), so far known to be endemic to the Espirito Santo State, Brazil, are here described and illustrated for the first time. Philodendron bernardopazii has been traded as an ornamental plant for more than 30 years, as one of several species popularly called Philodendron“Santa Leopoldina”, because of the Brazilian county where it has been collected. This new species is so far known from two cultivated stocks, both supposedly collected at the same location (around the village of Santa Leopoldina) and if it still exists in nature, it is probably threatened. Philodendron ricardoi has only been observed on rocks around the village of Estrela do Norte where huge populations can be seen growing in rocky outcrops in open areas. 相似文献