Species composition, abundance and seasonal recruitment patterns of freshwater eels (Anguilla spp.) to Viti Levu, Fiji Islands, in the western South Pacific

2018 ◽  
Vol 69 (11) ◽  
pp. 1704 ◽  
Author(s):  
C. A. Hewavitharane ◽  
T. D. Pickering ◽  
R. Ciro ◽  
N. Mochioka

To understand the inshore recruitment mechanisms of tropical eels (Anguilla spp.), we collected 1368 glass eels at the mouth of a small river at Namelimeli, ~2km east of Navua Town, Fiji Islands, between April 2015 and June 2016. Specimens were identified using both morphological characters and DNA barcoding to only three species: one short-finned Anguilla obscura and two long-finned eels A. marmorata and A. megastoma. Anguilla obscura was the most abundant species (55% of glass eels collected) with peak recruitment periods from February to April. Anguilla marmorata was the second most abundant species (41.4% of glass eels collected) with peak recruitment periods in April 2015 and September–October 2015. Anguilla megastoma only comprised 3.9% of glass eels collected, with peak recruitment periods in April 2015 and October 2015. Anguilla obscura and A. marmorata were present in samples almost throughout the year, suggesting that tropical eels recruit to some degree throughout the year. Results suggest that peak recruitment occurs during seasons of heavy rain, from September to October and from February to April commencing 1h after sunset on the day following a new moon.


2016 ◽  
Vol 7 (2) ◽  
Author(s):  
Agus Alim Hakim ◽  
M Mukhlis Kamal ◽  
Nurlisa A Butet ◽  
Ridwan Affandi

Freshwater eel (Anguilla spp.) is a catadromus fish that migrates from freshwater into seawater for spawning and return to freshwater during larvae stage to grow. The objective of this study was to determine species composition of tropical freshwater eels based on morphology collected from several rivers flowing in to the Palabuhan Ratu Bay. Young, adult, and glass eels were caught in August 2014 until Desember 2014. Glass eels were only caught in Cimandiri River. Freshwater eels were classified by ano-dorsal length (AD) divided by total length (TL), cluster analysis, and discriminant analysis based on morphometric data. The results showed different AD/TL of young and adult, i.e., 1.93±0.51 for A. bicolor bicolor, and 16.99±0.65 for A. marmorata, and three different AD/TL of glass eels i.e.,1.72±1.05 for A. bicolor bicolor6.60±1.79 for A. nebulosa nebulosa, and 15.07±1.04 for A. marmorata. Cluster analysis showed three groups of population  characters of young and adult eels i.e.  A. bicolor bicolor (2 groups) and A. marmorata (1 group). Discriminant analysis showed three groups of glass eels population i.e., A. bicolor bicolor, A. nebulosa nebulosa, and A. marmorata. Morphological identification showed that young and adult eels in Cibareno  and Citepus rivers had two species i.e., A. bicolor bicolor and A. marmorata. Glass eels from Cimandiri river had three species i.e., A. bicolorbicolor, A. nebulosanebulosa, and A. marmorata. A. bicolor bicolor was found in each rivers and as a dominant species in Palabuhan Ratu Bay.Keywords: A. bicolor bicolor, A. marmorata, A. nebulosa nebulosa, species composition



2012 ◽  
Vol 7 (2) ◽  
pp. 139 ◽  
Author(s):  
Melta Rini Fahmi ◽  
Laurent Pouyaud ◽  
Patrick Berrebi

Tropical eels living in Indonesian waters are known to be composed of several species, but their real listing together with their distribution ranges need to be established. The main difficulties are the very high number of islands with perennial rivers where these species are living during the growth phase of their life cycle. It is difficult, sometimes impossible, to determine the species using morphological characters, moreover on glass eels. In order to establish the geographic distribution of tropical eels of the genus Anguilla in Indonesian waters, a total 1,115 specimens were collected between 2008 and 2012. Sample collection was done in the growth habitats that are rivers and estuaries by commercial nets of different categories according to the fish size. All samples were identified genetically using the recently developed semimultiplex PCR method. We recognized four species and subspecies with wide distribution: Anguilla bicolor bicolor, Anguilla bicolor pacifica, Anguilla marmorata, and Anguilla interioris; two species with limited distribution, close to endemism: Anguilla celebesensis and Anguilla borneensis and one subspecies Anguilla nebulosa nebulosa that is only spread in river flowing into Indian Ocean.



2020 ◽  
Vol 71 (4) ◽  
pp. 452 ◽  
Author(s):  
C. A. Hewavitharane ◽  
T. D. Pickering ◽  
C. Rico ◽  
N. Mochioka

Abstract. The oceanic early life histories of three species of tropical anguillid glass eels, namely Anguilla marmorata, Anguilla megastoma and Anguilla obscura, recruiting to Viti Levu, Fiji Islands, in the western South Pacific, were studied using otolith microstructures of 94 individuals. A. megastoma had the shortest leptocephalus duration, age at recruitment and metamorphosis stage (mean±s.d. 104.7±7.2, 141.3±8.7 and 36.6±8.5 days respectively), followed by A. marmorata (September–October recruitment peak: 113.0±11.9, 115.1±8.3 and 39.2±11.1 days respectively; April recruitment peak: 152.2±13.5, 154.0±12.5 and 38.9±10.1 days respectively) and A. obscura (118.0±10.2, 168.4±16.5 and 49.6±12.5 days respectively). A. obscura also had the shortest oceanic glass eel duration of (12.2±3.4 days), followed by both peaks of A. marmorata (23.3±3.2 and 20.2±3.3 days) and A. megastoma (20.7±6.7 days). Otolith increment rates during the leptocephalus stage did not differ significantly among the three species, but there were significant differences between the leptocephalus duration and metamorphosis stage of A. megastoma compared with A. marmorata and A. obscura, as well as in the oceanic glass eel duration of A. obscura compared with A. marmorata and A. megastoma. There were also significant differences in the age at recruitment among all three species. Back-calculated hatch dates suggest separate peak seasonal spawning periods for each of the three species.



Author(s):  
M.D. Wildsmith ◽  
I.C. Potter ◽  
F.J. Valesini ◽  
M.E. Platell

Benthic macroinvertebrates were sampled seasonally in the subtidal and upper and lower swash zones at two sites in each of six nearshore habitat types on the lower west coast of Australia. The habitat types, which differed mainly in the extent of their exposure to wave activity and whether sea grass and/or nearshore reefs were present, had been distinguished quantitatively using values for a suite of seven statistically-selected enduring environmental characteristics (Valesini et al., 2003). The core samples yielded 121 species representing eight phyla, among which the Polychaeta, Malacostraca and Bivalvia were the most speciose classes, contributing ∼38, 23 and 10%, respectively, to the total number of individuals. The total number of species and mean density of macroinvertebrates at the most protected habitat type (1), i.e. 70 and 209·2 individuals 0·1 m−2, respectively, were far greater than in any other habitat type. Habitat type influenced species composition to a greater extent than either zone or season. Furthermore, the extents of the differences among the species compositions of the six habitat types statistically matched the extents of the differences among the values for the suite of enduring environmental characteristics that distinguished each of those habitat types. Overall, the species composition at habitat type 1 was the most distinct, containing five abundant species of polychaetes that were adapted to deposit-feeding in calm waters with high levels of organic material and which were rare in all other habitat types. In contrast, the fauna at the most exposed habitat type was characterized by four crustacean species and a species of bivalve and polychaete, whose mobility and tough external surface facilitated their survival and feeding in turbulent waters. The zonal differences in faunal compositions among habitat types were greatest in the case of the subtidal zone. The faunal compositions differed among zones and seasons only at the most protected habitat type.



Insects ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 302
Author(s):  
Marek Michalski ◽  
Piotr Gadawski ◽  
Joanna Klemm ◽  
Krzysztof Szpila

The only European Stratiomyidae species known for feeding on human corpses was the black soldier fly Hermetia illucens (Linnaeus, 1758). Analysis of fauna found on a human corpse, discovered in central Poland, revealed the presence of feeding larvae of another species from this family: the twin-spot centurion fly Sargus bipunctatus (Scopoli, 1763). The investigated corpse was in a stage of advanced decomposition. The larvae were mainly observed in the adipocere formed on the back and lower limbs of the corpse, and in the mixture of litter and lumps of adipocere located under the corpse. Adult specimens and larvae were identified based on morphological characters, and final identification was confirmed using DNA barcoding. Implementing a combination of morphological and molecular methods provided a reliable way for distinguishing the larvae of S. bipunctatus and H. illucens. The potential of S. bipunctatus for practical applications in forensic entomology is currently difficult to assess. Wide and reliable use of S. bipunctatus in the practice of forensic entomology requires further studies of the bionomy of this fly.



2015 ◽  
Vol 33 (3) ◽  
pp. 590-596 ◽  
Author(s):  
Yalu Fang ◽  
Yoshiaki Kai ◽  
Takashi Yanagimoto ◽  
Na Song ◽  
Tianxiang Gao


2016 ◽  
Vol 106 (0) ◽  
Author(s):  
Rodrigo M. Mello ◽  
Pedro H. Nobre ◽  
Marco A. Manhães ◽  
Alexmar S. Rodrigues

ABSTRACT Many studies have demonstrated the ecological relevance and great biodiversity of bats in Brazil. However, mountainous areas have been disproportionately less sampled, mainly in the Southeast. The aim of this study was to identify and compare the richness and diversity of Phyllostomidae, the most diverse bat family, in different forest types in Parque Estadual do Ibitipoca, trying to understand the causes of possible differences. The Parque Estadual do Ibitipoca is inserted in the Serra da Mantiqueira's domain, in an Atlantic Forest region known as "Zona da Mata", state of Minas Gerais, with an altitudinal range between 1200-1784 meters. The study was conducted in two forest types, classified as "Nanofloresta Nebular" and "Floresta Nebular", whose respective data on richness and diversity were compared. The bats were captured with 8-10 mist nets for 14 months (April 2011 to May 2012) and four nights per month totaling 62,171.25 m2h of capture effort. A total of 392 captures (12 species) belonging to the Phyllostomidae family were obtained. The most abundant species were Sturnira lilium (59.9%), Platyrrhinus lineatus (11.3%), Artibeus lituratus (8.7%) and Carollia perspicillata (7.6%). The two sampled areas presented differences in bat richness, diversity and species composition, and this difference was predominantly influenced by S. lilium. It is likely that the observed difference in the assembly of bats between the two study sites depends on the variation in floristic composition. The records of A. lituratus and P. lineatus in a few months of the year and close to Ficus mexiae bearing ripe fruits suggests that at least these species move to the park for a few periods of the year in search of food resources, possibly moving through the altitudinal landscapes.



2021 ◽  
Vol 32 (2) ◽  
pp. 293-301
Author(s):  
MD JAYEDUL ISLAM ◽  
SHARMIN AKTER ◽  
PROVAKOR SARKAR ◽  
MOHAMMAD RASHED ◽  
IREEN PARVIN ◽  
...  

A new record of Plectropomus pessuliferus (Serranidae: Epinephelinae) wasdocumented based on morphological characters and DNA barcoding. The species was collectedduring a regular survey for making an inventory of reef associated fishes in Saint Martin`sIsland, Bangladesh. This is the first report of roving coral grouper from the marine waters ofBangladesh validated by morpho-meristic analysis and DNA barcoding. This is also the firstreport from the northern Bay of Bengal.



1988 ◽  
Vol 18 (3-4) ◽  
pp. 309-315 ◽  
Author(s):  
Heraldo Luís de Vasconcelos

One hundred and fourteen hectares of a "terra-fiirme" rain forest 70 km north of Manaus, Amazonas, Brazil, were surveyed for leaf-cutting ant colonies (Atta spp). One half of this area was in isolated forest fragments (surrounded by pastures or second growth) of two sizes: 1 and 10 ha. The other half was in non-isolated fragments (connected to a large parch of forest) of the same sizes. Only two species occured in this forest: Atta sexdens sexdens L. and A. cepfhalotes L. The first was the most abundant species with a mean density of 0.35 colonies per ha. The mean density of A. cephalotes colonies was 0.03 per ha. The density of colonies was not significantly different between the isolated fragments and the continuous forest. Furthermore, the species composition did not change with isolation. However, pre-isolation data and long term monitoring are necessary to conclude that the isolation of a forest fragment has no effect upon Atta colonies. The non-uniform spatial distribution of Atta colonics within the "terra-firme" forest must be taken into account when selecting conservation areas in the Amazon, in order to preserve this important group of ants together with their native habitat.



2019 ◽  
Author(s):  
Erwan Delrieu-Trottin ◽  
Jeffrey T. Williams ◽  
Diane Pitassy ◽  
Amy Driskell ◽  
Nicolas Hubert ◽  
...  

AbstractThe emergence of DNA barcoding and metabarcoding opened new ways to study biological diversity, however, the completion of DNA barcode libraries is fundamental for such approaches to succeed. This dataset is a DNA barcode reference library (fragment of Cytochrome Oxydase I gene) for 2,190 specimens representing at least 540 species of shore fishes collected over 10 years at 154 sites across the four volcanic archipelagos of French Polynesia; the Austral, Gambier, Marquesas and Society Islands, a 5,000,000 km2area. At present, 65% of the known shore fish species of these archipelagoes possess a DNA barcode associated with preserved, photographed, tissue sampled and cataloged specimens, and extensive collection locality data. This dataset represents one of the most comprehensive DNA barcoding efforts for a vertebrate fauna to date. Considering the challenges associated with the conservation of coral reef fishes and the difficulties of accurately identifying species using morphological characters, this publicly available library is expected to be helpful for both authorities and academics in various fields.



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