Freshwater testate amoebae from waterbodies of North Vietnam with the finding of indicator species

Tran, Hoan Q.; Tran, Van Tiep; Tikhonenkov, Denis V.

doi:10.1007/s10201-020-00642-y

Cited by 12 publications

(4 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The climatic, geographical, and natural diversity of these habitats determines its unique richness and the significance of biodiversity that characterises this region of Southeast Asia. Recently, there has been a significant increase in interest in the study of protists in Vietnam [10][11][12][13][14]. In the last decade, many new and endemic taxa of algae and heterotrophic protists have been described from freshwaters of the country, including diatoms [15][16][17][18][19][20][21], cryptomonads [22,23], heterotrophic flagellates [24,25], centrohelid heliozoans [26], and testate amoebae [27].…”

Section: Introductionmentioning

confidence: 99%

Diversity of Silica-Scaled Chrysophytes in Central Vietnam

Gusev

Martynenko

2021

Water

View full text Add to dashboard Cite

This paper focuses on the flora of scale-bearing chrysophytes from eight provinces located in the central part of Vietnam. Khanh Hoa, Phu Yen, Binh Dinh, Thua Thien Hue, Quang Tri, and Quang Binh provinces are located in the coastal area of Vietnam. Lam Dong and Dak Lak provinces represent mountain territories with an elevation of 500–2000 metres above sea level. In total, 212 water bodies of different origins were studied. Samples were obtained from swamp areas, lakes, rivers, reservoirs, ponds, and small temporary water bodies. In total, 76 taxa were identified by electron microscopic observations of samples. A total of 54 taxa were found in the mountainous provinces, while 73 were found in the coastal provinces. Of these, 51 species are common for both areas. The most diverse was the genus Mallomonas with 66 species, varieties, and forms; followed by Synura with 7 taxa; Chrysosphaerella with 2; and Spiniferomonas with 1. Seven taxa of the genus Mallomonas were not identified to the lower rank. All these unidentified specimens may potentially represent new species for science. Ten taxa are reported for the first time in Vietnam.

show abstract

Section: Introductionmentioning

confidence: 99%

Diversity of Silica-Scaled Chrysophytes in Central Vietnam

Gusev

Martynenko

2021

Water

View full text Add to dashboard Cite

show abstract

“…In the upper part of the metalimnion, we observed the highest Shannon index and greatest species richness along the transect, and the assemblages associated with this site were dominated by the ubiquitous species Centropyxis cassis , Cylindrifflugia elegans, Difflugia penardi and Centropyxis aculeata (Davidova, 2010; Davidova et al., 2008; Ju et al., 2014; Regalado et al., 2018; Todorov, 2004; Tran, 2020; Tran et al., 2021), which we attribute to the high variability of temperature and grain size, high DO and good availability of food sources. In the low metalimnion zone, where the temperature gradient became much smaller and the sediment content became more homogeneous, the values of the Shannon indices and species richness were somewhat lower than those in the upper metalimnion zone.…”

Section: Discussionmentioning

confidence: 86%

Metalimnion as an ecotone in stratified freshwater lakes: A case study on benthic testate amoebae in Lake Valdayskoe

Sysoev,

Seleznev,

Reshetnikov

et al. 2024

Freshwater Biology

View full text Add to dashboard Cite

Testate amoebae are widely used as bioindicators in the study of modern ecotopes and as proxies in palaeoecological reconstructions of lacustrine environments. The metalimnion with thermocline in stratified water bodies strongly affects the species structure of a number of aquatic animals and often plays a role as an ecotone for pelagic animals, but our knowledge on the influence of the metalinmion on benthic organisms, especially on testate amoebae, is still limited. This study aims to describe the influence of the metalimnion and its thermocline on benthic testate amoebae assemblages along a temperature gradient in the stratified freshwater Lake Valdayskoe. Twenty‐eight samples from nine sites were collected along the transect starting in the littoral zone, passing through a long metalimnion and its thermocline and finishing in the hypolimnion on the bottom slope. We identified four species assemblages, six non‐attributed samples and five morphotrait compositions in the transect, including those corresponding to the area inside the metalimnetic zone. We observed similarities in the transitions in benthic species assemblages, morphotype compositions, and species and morphotrait structures from shallow to deep water, and two shifts corresponded well with the upper and lower limnological boundaries of the metalimnion. The combination of the observed biological and hydrological characteristics suggests that the metalimnion plays a role of an ecotone between shallow and deep water in stratified freshwater lakes, and maintains the integrity and sustainability of benthic communities of testate amoebae. We explored a multivariate approach to demonstrate that the combination of highly abundant species and dominant morphotypes may be an efficient indicator of related environmental conditions. Thus, the high abundances of Cylindrifflugia acuminata, Centropyxis aculeata, Difflugia lacustris, D. linearis and C. discoides in combination with the dominance of elongate‐spiky and flattened‐spiky shells are closely related to the littoral zone with sandy sediments covered by many macrophytes. The combination of a high abundance of D. petricola and D. penardi, and the dominance of pyriform, necked and oval shells are closely related to deep depth. The studied species and morphotrait transition from littoral to deep water provides additional information about the morphological adaptations of testaceans, and about the processes of forming and maintaining benthic testate amoebae assemblages along the depth gradient. The described species and morphotrait assemblages related to specific water depths may be useful for palaeoreconstructions.

show abstract

“…The latter species shows a shell made both of exogenous particles and by biogenic siliceous structures (Beyens and Meisterfeld, 2001;Todorov and Bankov, 2019) and prefers alkaline pH levels (Payne et al, 2008). Moreover, L. modesta could be found in habitats with a presence of high detritus content and macrophytes (Lansac-Tôha et al, 2014;Siemensma, 2021), and it has been recognized that the species could be considered an indicator of both macrophytes and periphyton (Tran et al, 2021). In addition, the occurrence of D. rotunda is related to habitats with epiphytic vegetation and/or planktonic organisms (Marcisz et al, 2020).…”

Section: Temporal Changes In Testate Amoeba Assemblagesmentioning

confidence: 99%