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1.
Zootaxa ; 4688(3): zootaxa.4688.3.11, 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31719445

RESUMO

The Andaman and Nicobar group of islands (11.7401°N, 92.6586°E) are surrounded by the Bay of Bengal to the west and Andaman Sea to the east. The species reported in this paper belongs to the superfamily Gonodactyloidea, which are generally "smashers", i.e. the dactylus of their raptorial appendage is greatly inflated at the base and used to break open hard-bodied prey (Ahyong 1997). Most smashers live in rock and coral cavities and have a heavily armoured telson for defensive and offensive purposes (Caldwell Dingle 1975). Studies on the family Gonodactylidae from these islands have been limited and few have been reported so far (Jayabarathi et al. 2013; Kumaralingam Raghunathan 2016; Kumaralingam et al. 2017). Recent field studies in the Andaman Islands collected a specimen of the Gonodactylus smithii, reported herein.


Assuntos
Antozoários , Crustáceos , Animais , Índia , Ilhas
2.
Environ Monit Assess ; 189(12): 614, 2017 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-29110106

RESUMO

The interaction between the environment and heterotrophic dinoflagellates inhabiting coastal waters of South Andaman was studied based on year round collections made during September 2012-August 2013 in the bay, eastern, and western region of South Andaman. The distribution pattern of microzooplankton in South Andaman showed high abundance in eutrophic waters (bay region) and gradually decreased towards the off shore region. Microzooplankton community comprised of six different taxa, viz. tintinnids, heterotrophic dinoflagellates, non-loricate ciliates, Foraminifera, Rotifera, and Copepoda (nauplii). Tintinnids were the major component of the microzooplankton (43.8 ± 7%) followed by heterotrophic dinoflagellates (34 ± 12%) and copepod nauplii (18.8 ± 4.0%). This study focused on heterotrophic dinoflagellates which ranked next to tintinnids in overall abundance and contributed 38-42% in the bay, 22-37% in the eastern, and 15-29% in the western region to the microzooplankton community. Dinoflagellates showed a positive correlation with salinity and a negative correlation with dissolved oxygen and chlorophyll a (r = - 0.3). Abundance of heterotrophic dinoflagellates in this area may be due to their diverse and advantageous mode of nutrition. A total of 35 species belonging to 8 genera of heterotrophic dinoflagellates were recorded during the study period. Heterotrophic dinoflagellates showed a great potential to thrive in low oxygenated and low productive area (p < 0.001, Mann-Whitney test). Relatively higher diversity (H') in the dinoflagellates population was found in the bay region (avg. H' = 3.46).


Assuntos
Dinoflagelados/classificação , Monitoramento Ambiental , Animais , Clorofila/análise , Clorofila A , Cilióforos/classificação , Copépodes , Dinoflagelados/fisiologia , Índia , Rotíferos , Salinidade , Estações do Ano , Água do Mar/química
3.
Environ Monit Assess ; 189(1): 13, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27957677

RESUMO

We report on the seasonal and spatial variations of microzooplankton between polluted and moderately polluted coastal waters of South Andaman Island, in relation to certain physicochemical and biological parameters. Microzooplankton communities were studied and recorded for 1 year (September 2011 to August 2012) during the northeast monsoon, the intermonsoon, and the southwest monsoon periods. We recorded a total of 75 species belonging to 29 genera, of which polluted waters encompassed 71 species (28 genera). In contrast, only 59 species (22 genera) were recorded in the moderately polluted waters. We discovered that taxonomic composition, biomass, and abundance of microzooplankton not only varied spatially but also altered seasonally. It is noteworthy to state that the northeast monsoon played a significant role in controlling the abundance of microzooplankton in South Andaman coastal waters.


Assuntos
Monitoramento Ambiental/métodos , Poluição Ambiental , Zooplâncton , Animais , Estações do Ano
4.
Aquat Biosyst ; 8(1): 20, 2012 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-22938564

RESUMO

BACKGROUND: Microzooplankton consisting of protists and metazoa <200 µm. It displays unique feeding mechanisms and behaviours that allow them to graze cells up to five times their own volume. They can grow at rates which equal or exceed prey growth and can serve as a viable food source for metazoans. Moreover, they are individually inconspicuous, their recognition as significant consumers of oceanic primary production. The microzooplankton can be the dominant consumers of phytoplankton production in both oligo- and eutrophic regions of the ocean and are capable of consuming >100% of primary production. RESULTS: The microzooplankton of the South Andaman Sea were investigated during September 2011 to January 2012. A total of 44 species belong to 19 genera were recorded in this study. Tintinnids made larger contribution to the total abundance (34%) followed in order by dinoflagellates (24%), ciliates (20%) and copepod nauplii (18%). Foraminifera were numerically less (4%). Tintinnids were represented by 20 species belong to 13 genera, Heterotrophic dinoflagellates were represented by 17 species belong to 3 genera and Ciliates comprised 5 species belong to 3 genera. Eutintinus tineus, Tintinnopsis cylindrical, T. incertum, Protoperidinium divergens, Lomaniella oviformes, Strombidium minimum were the most prevalent microzooplankton. Standing stock of tintinnids ranged from 30-80 cells.L-1 and showed a reverse distribution with the distribution of chlorophyll a relatively higher species diversity and equitability was found in polluted harbour areas. CONCLUSIONS: The change of environmental variability affects the species composition and abundance of microzooplankton varied spatially and temporarily. The observations clearly demonstrated that the harbor area differed considerably from other area in terms of species present and phytoplankton biomass. Further, the phytoplankton abundance is showed to be strongly influenced by tintinnid with respect to the relationship of prey-predator. Consequently, further investigation on microzooplankton grazing would shed light on food web dynamics.

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