BRACKISH WATER AND FRESHWATER SPECIES OF THE DIATOM GENUS SKELETONEMA.
 II. SKELETONEMA POTAMOS
 COMB. NOV.1

Benthic organisms are important components of aquatic ecosystems and have been widely used to assess environmental pollution. Being very sensitive to a wide range of toxicants amphipods are often used as test objects in eco-toxicological studies. The aim of this study was to compare toxico-resistance of various Baltic amphipod species to exposure of heavy metals. The acute toxicity (48-h LC50 and 96-h LC50) of cadmium (CdCl2), copper (CuSO4) and zinc (ZnSO4 ⋅ 7H2O) was detected experimentally, using juveniles and adults of brackish water amphipods, Monoporeia affinis, Bathyporeia pilosa, Gammarus tigrinus, Pontogammarus robustoides and the freshwater amphipod Gammarus pulex as test objects. Amphipods were collected in Latvian territorial waters of the Open Baltic Sea, the Gulf of Riga and in a freshwater body (Kalkugrava canal). Sensitivity of native amphipod species was compared to Hyalella azteca (a species widespread in North America; a strain obtained from the Chesapeake Culture Collection, Hayes, VA, U.S.A.). High sensitivity of all tested amphipod species, except M. affinis, to heavy metals was observed. A two-way ANOVA analysis showed significant differences in toxico-resistance of selected test objects (). The highest toxico-resistance was shown by the brackish water amphipod M. affinis (96-h LC50: Cd 5.16 mg/l; Cu 5.68 mg/l; Zn 11.31 mg/l), but the lowest by the freshwater species G. pulex and H. azteca (96-h LC50 for Cd 0.005 and 0.007 mg/l, accordingly). Cadmium was the most toxic from the tested heavy metals, followed by copper and zinc.

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Entomostraca

Philosophical Transactions of the Royal Society of London ◽

10.1098/rstl.1879.0018 ◽

1879 ◽

Vol 168 ◽

pp. 215-218 ◽

Cited By ~ 2

Keyword(s):

Brackish Water ◽

High Water ◽

Freshwater Lake ◽

The Other ◽

Calanus Finmarchicus ◽

Freshwater Species ◽

Kerguelen Island ◽

High Water Mark ◽

Oceanic Species

[Ostracoda. All of the Ostracoda collected by me in Kerguelen Island were lost by a breakage.—A. E. E.] Copepoda. The Entomostraca submitted to me were taken in the following localities:—One surface-net gathering, in lat. 35° 9' S., long. 45° 30' E.; another gathering from a freshwater lake, and a third from a pool above high-water mark, both in Kerguelen Island. The oceanic species were Calanus Finmarchicus and a Sapphirina , either identical with or very closely allied to S. danœ , Lubbock; those from Kerguelen Island were a freshwater species, apparently new, described by me briefly in Ann. and Mag. Nat. Hist., Sept. 1875, under the name Centropages brevicaudatus ; and a species from brackish water, Harpacticus fulvus . No species have yet been recorded by the other Expeditions.

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Fossil species of the diatom genus Tetracyclus (Bacillariophyta, ‘ellipticus’ species group): morphology, interrelationships and the relevance of ontogeny

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.1996.0156 ◽

1996 ◽

Vol 351 (1348) ◽

pp. 1759-1782 ◽

Cited By ~ 20

Keyword(s):

Species Group ◽

Life Cycles ◽

Freshwater Species ◽

Fossil Species ◽

Variable Property ◽

Elliptical Shape ◽

Diatom Genus ◽

Diatom Valve

The diatom genus Tetracyclus Ralfs (Bacillariophyta) is composed largely of extinct, freshwater species many of which have been used as stratigraphic markers across several continents under the assumption that they are relatively widespread and confined to precise geological epochs. Until recently the taxonomy of the genus relied almost exclusively on the shape and dimensions of the preserved siliceous valves. This study forms part of a revision of the entire genus. In this paper the morphology of fossils from the ‘ellipticus’ species group is discussed. Significant to this study is the relative usefulness of diatom valve dimensions and overall shape, seen here in the context of siliceous morphogenesis and the appearance of particular valve ‘shapes’ at particular stages in their life cycles. In addition, alternative ways of representing character data have been applied to establish whether the ‘ellipticus’ species group is monophyletic with respect to the genus. Results suggest that the ‘ellipticus’ species group is not monophyletic and that the elliptical shape of valves is better viewed as a variable property of ontogeny.

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Mismatch between molecular (mtDNA) and morphological classification of Macrobrachium prawns from Southern Nigeria: Cryptic freshwater species and brackish water morphotypes

Aquaculture ◽

10.1016/j.aquaculture.2013.06.013 ◽

2013 ◽

Vol 410-411 ◽

pp. 25-31 ◽

Cited By ~ 3

Author(s):

Abayomi A. Jimoh ◽

Martins A. Anetekhai ◽

Steve Cummings ◽

Olatunji T.F. Abanikanda ◽

George F. Turner ◽

...

Keyword(s):

Brackish Water ◽

Freshwater Species ◽

Morphological Classification ◽

Southern Nigeria

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Biological Conservation of Molluscs Based on Spatial and Temporal Distribution in Tropical Tidal Lake, Medan-Indonesia

HAYATI Journal of Biosciences ◽

10.4308/hjb.27.4.273 ◽

2020 ◽

Vol 27 (4) ◽

pp. 273

Author(s):

Fredinan Yulianda ◽

Ahmad Muhtadi ◽

Mennofatria Boer ◽

Majariana Krisanti ◽

Yusli Wardiatno

Keyword(s):

Brackish Water ◽

High Tide ◽

Temporal Distribution ◽

Conservation Strategy ◽

Lake Ecosystem ◽

Freshwater Species ◽

Spatial And Temporal Distribution ◽

Mollusc Species ◽

Brackish Water Species ◽

Malacca Strait

The tidal lake ecosystem is formed by the flow of the Belmera River and seawater through a tidal process along a course of 12 km from Belawan (Malacca Strait). This lake has a tidal lake that has the characteristics of fresh water to brackish water and Mollusc communities from freshwater species to brackish water species. This study was performed to develop a mollusc conservation strategy based on the spatial and temporal distribution of Mollusca in the tides. The study was conducted from September 2018-August 2019. Mollusc samples were taken every month at high tide and low tide using a Petersen grab tool. Nine Mollusca species, consisting of three bivalves and six gastropods, were identified. Polymedosa expansa is a mollusc species that is considered for conservation. The population size of P. expansa is small, and its distribution is limited to the northern lake. P. expansa was found only in September at high tide and in December at low tide. Competition among Mollusca and habitat availability are obstacles to the survival of P. expansa. The habitat of P. expansa is mangrove, and therefore a conservation approach was carried out through improvement of mangrove quality.

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LISTA PRELIMINAR DE LOS MOLUSCOS DE LA CIÉNAGA GRANDE DE SANTA MARTA (COLOMBIA)

Bulletin of Marine and Coastal Research ◽

10.25268/bimc.invemar.1973.7.0.546 ◽

2016 ◽

Vol 7 ◽

Author(s):

Rudo Von Cosel

Keyword(s):

Environmental Factors ◽

Brackish Water ◽

Freshwater Species ◽

Actual Distribution ◽

Mollusc Species

38 mollusc species of 24 families and 30 genera, living in the Ciénaga Grande de Santa Marta or its mouth are listed. Among these 32 are marine, tolerating brackish water (marine euryhaline), 4 extremely euryhaline and 2 freshwater species (limnetic). Empty shells of some species have a much greater distribution in the Ciénaga than the actual distribution of the live species. The environmental factors of the Ciénaga are described briefly.

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Species diversity of the marine diatom genus Skeletonema in Japanese brackish water areas

Fisheries Science ◽

10.1007/s12562-013-0671-0 ◽

2013 ◽

Vol 79 (6) ◽

pp. 923-934 ◽

Cited By ~ 9

Author(s):

Machiko Yamada ◽

Mayuko Otsubo ◽

Yuki Tsutsumi ◽

Chiaki Mizota ◽

Naoki Iida ◽

...

Keyword(s):

Species Diversity ◽

Brackish Water ◽

Marine Diatom ◽

Diatom Genus

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A new species of Halicyclops (Copepoda, Cyclopoida, Halicyclopinae) from an estuarine system of the Caribbean Coast of Colombia

Acta Biológica Colombiana ◽

10.15446/abc.v25n1.74842 ◽

2020 ◽

Vol 25 (1) ◽

pp. 14-21

Author(s):

Juan Manuel Fuentes-Reinés ◽

Eduardo Suárez-Morales

Keyword(s):

New Species ◽

Brackish Water ◽

Relative Length ◽

Caribbean Region ◽

Estuarine System ◽

Freshwater Species ◽

Male And Female ◽

The Caribbean ◽

A New Species ◽

Copepoda Cyclopoida

Plankton samples obtained from the Ciénaga Grande de Santa Marta, an extensive estuarine system in northern Colombia, yielded adult male and female specimens of an undescribed halicyclopine cyclopid copepod of the genus Halicyclops. Cyclopid copepods are frequently found in freshwater and transitional habitats. Members of the subfamily Halicyclopinae are chiefly brackish water forms with a few freshwater species. The new species described herein is assignable to the group of species “F” of Halicyclops (sensu Pesce, 2018) with a 2333 exopodal spine formula. Currently, this group contains five species and one subspecies. Halicyclops gutierrezi sp. n. can be distinguished from its known congeners by the absence of an anal operculum, the relative length of setae of the female and male P5, the relative length of the inner setae of P4EXP3, and details of the male antennule. This is the fifth species of Halicyclops recorded from Colombia and the first one of Halicyclops group “F” described from the Caribbean region. With the addition of H. gutierrezi sp. n., the number of species of the genus known from the Neotropics increased to 20. A key to the species of the genus recorded in Colombia is also provided.

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