scholarly journals Fish assemblage composition within the floodplain habitat mosaic of a tropical lake (Tonle Sap, Cambodia)

2019 ◽  
Vol 64 (11) ◽  
pp. 2026-2036 ◽  
Author(s):  
Thomas Pool ◽  
Vittoria Elliott ◽  
Gordon Holtgrieve ◽  
Mauricio Arias ◽  
Irit Altman ◽  
...  
Water ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2506
Author(s):  
Kakada Pin ◽  
Savat Nut ◽  
Zeb Hogan ◽  
Sudeep Chandra ◽  
Samadee Saray ◽  
...  

Mekong River Basin is one of the world’s fish biodiversity hotspots. Fisheries of the Cambodian Mekong are characterized by high diversity and productivity. However, few studies have focused on broad scale patterns and fish assemblage structure of this important system at a national level. Here, we describe spatial and seasonal variation in fish assemblages by analyzing one year of daily fish catch data sampled at 32 sites covering Cambodia’s main inland water bodies. We recorded 125 fish species. Four clusters were distinguished based on assemblage composition similarity, and 95 indicator species were identified to characterize each of the identified assemblage clusters. High diversity fish assemblages were associated with the upper Mekong system and Mekong/Bassac/Tonle Sap Rivers in Kandal Province and southern Tonle Sap Lake while lower diversity assemblages were observed in the Mekong River in Kratie and the northern area of the Tonle Sap Lake. We find significant variation in the assemblage composition between wet and dry seasons, indicating strong seasonal species turnover within clusters. Length–weight relationship analysis indicated a negative allometric growth among a majority of indicator species, reflecting suboptimal conditions for growth. Our study establishes contemporary structure and diversity patterns in the Lower Mekong River system of Cambodia, which can be used to map fish biodiversity hotspots and assess key indicative fish stocks’ statuses for conservation and management.


2013 ◽  
Vol 11 (1) ◽  
pp. 85-94 ◽  
Author(s):  
Lucelia Nobre Carvalho ◽  
Luana Fidelis ◽  
Rafael Arruda ◽  
Andre Galuch ◽  
Jansen Zuanon

Floating litter banks are an ephemeral habitat consisting of branches, twigs, flowers, seeds, and fruits that are trapped on the stream water surface by a variety of retention mechanisms. These heterogeneous materials form a deep layer of dead plant matter that is colonized by a variety of organisms, including fish that forage on the aquatic macroinvertebrates found in this unique habitat. In this study, we aimed to characterize which fish species occupy the floating litter banks and their trophic characteristics, as well as determine if fish assemblage composition and species richness can be predicted by the size of the floating litter banks. Fish sampling was conducted in five rivers located in the Amazon basin. Of the 31 floating litter banks sampled that contained fish, 455 individuals were recorded and were distributed within 40 species, 15 families and five orders. Siluriformes were the most representative order among the samples and contained the largest number of families and species. The fish fauna sampled was mainly composed of carnivorous species that are typically found in submerged litter banks of Amazonian streams. The fish assemblage composition in the kinon can be predicted by the volume of the floating litter banks using both presence/absence and abundance data, but not its species richness. In conclusion, kinon banks harbor a rich fish assemblage that utilizes this habitat for shelter and feeding, and may function as a refuge for the fishes during the peak of the flooding season.


2004 ◽  
Vol 52 (1) ◽  
pp. 47-58 ◽  
Author(s):  
Henry L. Spach ◽  
Rodrigo S. Godefroid ◽  
César Santos ◽  
Roberto Schwarz Jr. ◽  
Guilherme M. L. de Queiroz

Annual variation in the fish assemblage characteristics on a tidal flat was studied in coastal Paraná, in southern Brazil. Fish were collected between August 1998 and July 1999, during the diurnal high tide and diurnal and nocturnal low tide of the syzygial (full moon) and quadrature (waning moon) tides, to characterize temporal change in assemblage composition. A total of 64,265 fish in 133 species were collected. The average number of species and individuals, biomass, species richness, diversity (mass) and equitability varied significantly over time . The dissimilarity of the assemblage was greatest in August, September and October in contrast with the period from November to January, with the lowest dissimilarity. The combined action of water temperature, salinity and wind intensity had a great influence over the structure of the fish assemblage.


Zootaxa ◽  
2019 ◽  
Vol 4615 (1) ◽  
pp. 57
Author(s):  
OLEG E. KOSTERIN

The taxa of the genus Macrogomphus Selys, 1858 occurring in continental south-east Asia are reconsidered. Macrogomphus rivularis Förster, 1914 (described from Vietnam), M. borikhanensis Fraser, 1933 (described from Laos), and M. guilinensis Chao, 1983 (described from China), are synonymised with M. albardae Selys, 1878. The relationship and conspecificity of the latter with M. parallelogramma Burmeister, 1839 are doubtful, perhaps they are bona species. Males of M. albardae (and seemingly of parallelogramma as well) are approximately trimorphic for the pale pattern of the abdominal S3–S6, being of either a ‘dashed morph’ (with small isolated anteriolateral spots and conspicuous middorsal streaks), or a ‘ringed morph (with broad anterior rings and less conspicuous middorsal streaks), or an ‘intermediate morph’. Validity of the species M. matsukii Asahina, 1986 is doubted; its holotype could be an aberrant male of M. albardae. The main diagnostic character of M. albardae, M. phalantus Lieftinck, 1935 and probably M. parallelogramma, is clarified to be the structure of the cercus inner branch. M. phalantus jayavarman subsp. nov. is described from temporarily inundated forest at the northern bank of the great Lake Tonlé Sap of Cambodia (Siem Reap Province, 1.5 km SSW of Kampong Pluk village, 13.1956° N, 103.9725° E, 3 m a.s.l.), which is ca 1,300 km north and overseas from the presumed range of M. phalantus phalantus. 


2012 ◽  
Vol 66 (3) ◽  
pp. 295-300 ◽  
Author(s):  
F Nemoto ◽  
H Kojima ◽  
A Ohtaka ◽  
M Fukui

Sign in / Sign up

Export Citation Format

Share Document