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1.
Abstract:The first lichen records from the Lakshadweep (Laccadive) Islands are presented.Lithothelium insulare (Pyrenulaceae) is described as new and nine other taxa are reported. The poor lichen flora, dominated by pantropical species, is probably a result of the lack of natural habitats in this area.  相似文献   

2.
Two new species of Mysidacea belonging to the genus Anisomysisare described from the Lakshadweep archipelago. Anisomysis spinatais characterized by a deeply cleft telson and is unique in havinga spine on the endopod of uropod. The broadly truncate apexof the telson and the stout apical spines are the distinctivecharacters of A.truncata.  相似文献   

3.
A single specimen of African angel shark, Squatina africana (Regan, 1908) was caught off Lakshadweep (11°5′47″ N; 72°2′21″ E), India in September 2016. The present study is a new report of the above species from Indian waters. In addition to classical methodologies, DNA barcoding was also adopted for species identification. The 650 bp-long region of mitochondrial Cytochrome Oxidase subunit I was sequenced to obtain the DNA barcode for the species under study. The sequence divergence value within species and between species was calculated using MEGA V.7.0, where Kimura 2 parameter (k2p) model was chosen as a distance model. The average k2p distance separating individuals within species was 1.76% and inter specific divergence was 8–10%. A neighbour joining network was constructed to provide a graphical representation of divergence between the species. Using the maximum identity with Gen Bank database, K2P divergence distance, NJ-network and traditional morphological approach, we could identify the given specimen as a mature male African angel shark.  相似文献   

4.
Length‐weight relationships (LWRs) of three needlefishes belonging to the family Belonidae viz., Ablennes hians, Tylosurus crocodilus and Tylosurus acus melanotus were estimated based on samples exploited from a gill‐net fishery in Androth, an island in the Lakshadweep archipelago. The estimated allometric co‐efficient b value ranged from 3.047 (T. acus melanotus) to 3.274 (A. hians), and r2 value ranged from 0.911 (T. acus melanotus) to 0.973 (A. hians). The first estimate of LWR for these three commercially exploited needlefish species from the Lakshadweep islands indicate local populations to be fairly robust and forms a basis for future management of fishing stock in the region.  相似文献   

5.
Bycatch from the experimental longline operations in the Lakshadweep Sea were studied. The experiments were conducted on converted Pablo boats, originally used for pole and line fishing operations, to capture skipjack tuna in the Lakshadweep Islands. The overall bycatch rate was very high, with a mean hooking rate of 8.05/1000 hooks compared to the targeted tuna catch (1.75/1000 hooks). Bycatch contributed 82.4% of the catch in comparison to the tuna (17.6%) Thunnus albacares, in the longline operations. Silky shark (Carcharhinus falciformes) with 89.9% was the dominant shark species followed by C. amblyrhynchos, Galeocerdo cuvier, Alopias pelagicus, Negapriion acutedens and Sphyrna lewinii with 4.7, 2.7, 1.4, 0.7 and 0.7%, respectively. Sharks contributed to 74.1% of the catch, followed by 15.7% sailfishes and 10.2% miscellaneous fishes. Higher bycatch rates were evident during evening hours compared to mornings, but the results were not significant statistically. Studies on the effects of depth on the overall fishing performance and species selectivity failed to establish any significant relationship at a depth range of 35–100 m. Soaking time had a significant effect on bycatch rates. The hooking rate of sharks declined with an increase in soaking time. Considering the high shark bycatch in the fishery, an accurate monitoring of the longline fish catches in the Lakshadweep waters is an important step towards ensuring the sustainability of other populations, especially sharks.  相似文献   

6.
Estimation of nutrition profile of edible fishes is essential and thus a bio-monitoring study was carried out to find out the nutritional composition of commonly available fishes in Agatti Island water of Lakshadweep Sea. Protein, carbohydrate, lipid, ash, vitamin, amino acid and fatty acid composition in the muscle of ten edible fish species were studied. Proximate analysis revealed that the protein, carbohydrate, lipid and ash contents were high in Thunnus albacares (13.69%), Parupeneus bifasciatus (6.12%), Hyporhamphus dussumieri (6.97%) and T. albacares (1.65%), respectively. Major amino acids were lysine, leucine and methionine, registering 2.84–4.56%, 2.67–4.18% and 2.64–3.91%, respectively. Fatty acid compositions ranged from 31.63% to 38.97% saturated (SFA), 21.99–26.30% monounsaturated (MUFAs), 30.32–35.11% polyunsaturated acids (PUFAs) and 2.86–7.79% branched fatty acids of the total fatty acids. The ω-3 and ω-6 PUFAs were ranged 13.05–21.14% and 6.88–9.82% of the total fatty acids, respectively. Hence, the fishes of Lakshadweep Sea are highly recommended for consumption, since these fishes are highly enriched with nutrition. The results can be used as a baseline data for comparing the various nutritional profiles of fishes in future.  相似文献   

7.
8.
The atoll reefs of the Lakshadweep, in the Indian Ocean suffered a catastrophic mortality of hard coral in the wake of the El Niño event of 1998. This study tracked changes to coral and other benthic elements in three atolls in the Lakshadweep from 2000 to 2003. The recovery of coral was highly site-specific, and appeared to be driven by differences in post-settlement survival of coral recruits, that were in turn, influenced by the local hydrodynamics of the atolls. Post bleaching recovery was highest on west-facing reefs, while recovery on east-facing reefs was very limited. However, no ‘phase-shift’ to macroalgal dominated reefs was evident. High herbivore pressures were perhaps the most important control of macroalgae. Five years after the mass mortality, the genera that showed the maximum gains represented a mix of different susceptibilities to bleaching, while some genera that were not particularly susceptible to bleaching showed significant declines. These results suggest that decline or recovery of coral is likely dependent on individual life history strategies, post-recruitment survival, and contingency.  相似文献   

9.
Wetlands Ecology and Management - Coral reefs of Lakshadweep perform a range of vital ecosystem functions and sustain the livelihoods of island communities. Coral reefs provide ecosystem services...  相似文献   

10.
Yadav  S.  Alcoverro  T.  Arthur  R. 《Coral reefs (Online)》2018,37(4):1245-1257
Coral Reefs - The resilience of reefs to repeated, increasingly frequent thermal disturbance is a dynamic balance between resistance and recovery pathways. The Lakshadweep archipelago in the...  相似文献   

11.
Seagrass environments, from the main coast of India, Lakshadweep and Andaman Islands, were surveyed for seagrass and marine algal composition. Extensive seagrass meadows and the maximum number of species (seven genera and 12 species) occurred along the Tamil Nadu coast. Seagrasses were observed from intertidal to subtidal regions down to 8 m depth. Thalassia hemprichii (Ehrenberg) Aschers. and Cymodocea serrulata (R. Brown) Aschers. & Magnus were the dominant seagrasses in the subtidal zones. Halophila beccarii Aschers. was restricted to the intertidal mudflats in association with mangroves. The rich growth of seagrasses along the Tamil Nadu coast and Lakshadweep can be attributed mainly to high salinity, clarity of the water and sandy substratum. One hundred species of marine algae were recorded from the seagrass environments of India.  相似文献   

12.
The mammoth steppe ecosystem was characterized by a high diversity in large mammals species distributed on a vast geographical range. The isotopic analyses of the collagen of the faunal remains from this context testified the niche partitioning among large herbivores with a specialization in the types of consumed plants. In the case of the mammoth (Mammuthus primigenius), systematic higher abundances in 15N are found for this species compared to those of other grazers in Eurasia and Alaska during the Upper Palaeolithic. This distinct isotopic signature reflects a specific ecological niche. The analyses of mammoth remains at the Epigravettian site of Mezhyrich (15,000–14,300 conv BP) reveal low abundances in 15N that are equivalent to those of the associated horses. Thus, the mammoth of Mezhyrich experienced a significant change in their environment and diet that probably led to the loss of their ecological niche. A likely direct competition with other large herbivores and the possible predation by wolves and human populations should be considered for the mammoth of the Ukrainian plains, long before their extirpation from the region.  相似文献   

13.
14.
Marine ecosystem of the Lakshadweep archipelago is unique and known to have a very high degree of biodiversity with a number of endemic flora and fauna. The present study focuses to isolate the endosymbiotic microorganism from sponges and its effectiveness against marine ornamental fish pathogens. The sponges were collected from Agatti island of Lakshadweep archipelago and identified as Clathria procera, Sigmadocia fibulata and Dysidea granulosa. In which, 15 different types of bacteria were isolated and screened against marine ornamental fish pathogens (A. hydrophila, Vibrio alginolyticus, V. harveyii, V. parahaemolyticus and Pseudomonas fluorescens). The strain S25 was found as potential bacteria based on their antimicrobial activity against the fish pathogens. Molecular identification of the potential strain (S25) of the 16S rRNA gene showed 99% identity with Acinetobacter sp. The sequenced 16 s rRNA gene with 1,081 bp in length was submitted in NCBI Genbank and Accession was obtained (GenBank Accession number HM004071). The strain exhibited high similarity (99%) with the 16S rRNA gene of Acinetobacter calcoaceticus from GenBank database. Crude extract obtained with acetone and ethyl acetate from extracellular products of S25 showed significant antimicrobial activity by disc diffusion assay using 1,500 μg/ml of crude extract. Extracellular metobolite of A. calcoaceticus was extracted by shake flask method and the crude extract was partially purified by thin layer chromatography. Partially purified crude extract showed significant inhibition zone of antimicrobial activity (A. hydrophila, V. alginolyticus, V. parahaemolyticus) and less similar activity against V. harveyii and P. fluorescens. This is the first report on A. calcoaceticus isolated from sponges of Lakshadweep archipelago and the studies are underway to characterize and purify the antimicrobial compounds of the potential bacteria.  相似文献   

15.
A study of the taphonomy and age profiles of the mole rat population from Langebaanweg ‘E’ Quarry was undertaken in order to see if these subterranean rodents had been accumulated by predation (coprocoenosis hypothesis) or as a result of drowning in their burrows during a flood event (catastrophocenosis hypothesis). Previous research has cited the bathyergids as being the most common rodent at Langebaanweg, however, a comprehensive study of new micromammal material indicates that murids, rather than mole rats, dominate most of the assemblages. The concentration of mole rat remains in many of the fossil-bearing levels at Langebaanweg is, nevertheless, still extremely high compared to other fossil sites or predation assemblages in the area. A taphonomic examination of mole rat incisor surfaces indicates that digestion occurs on between 44% and 54% of incisors in the different assemblages, and this, together with the degree of digestion suggests that category 1 and category 2 predators had been responsible for the accumulation of the fossil mole rat assemblages. The absence of rounding, polishing or weathering on the fossils indicates that there has been little or no transport by water, and that burial of the bones was rapid. Breakage and damage to the anterior portion of many of the mandibles made it impossible to accurately assess the age of the older mole rats, and the majority of mandibles could provide only a minimum age of the animal at the time of death. The age profile indicates that very young individuals are missing from the assemblages. This allows for refutation of the previously made suggestion that flooding was responsible for the death of the majority of Langebaanweg mole rats and also introduces the possibility that Bathyergus hendeyi may have been a social animal, unlike extant bathyergids which are solitary.  相似文献   

16.
Cibicidoides dispars and Cibicidoides variabilis are two neritic cibicidids commonly found on the Patagonian coasts. Phylogenetic analyses of partial SSU rDNA sequences show that they both belong to the genus Cibicidoides. Cibicidoides dispars branches close to Cibicidoides wuellerstorfi, whereas C. variabilis clusters with Cibicidoides pachyderma. In both cases, species clustering together are well separated morphologically and ecologically but close genetically. Molecular data indicate clearly that C. dispars and C. variabilis are well separated genetically from Cibicidoides lobatulus, another shallow water cibicidid sharing a similar ecology and morphology. Moreover, our molecular results show that neritic and bathyal or abyssal species are found together in different clades, suggesting multiple colonization events from shallow to deep water or vice versa. The analysis of more variable ITS rDNA region, on the other hand, reveals small differences between individuals of C. variabilis sampled in the south and north of Chilean Patagonia, which could indicate a cryptic speciation undergoing in this species.  相似文献   

17.
This work details the morphological analysis upon which the creation of the testudinid genus Eurotestudo was based. The study is presented in two parts. The present first part includes an introduction to the subject, and the morphological data with illustrations, which formed the basis for the analysis. The results and lists of cited taxa appear in the second part (Ann. Pal., 92, 4). The analysis rests on a limited number of selected characters, principally those derived from shell osteology, which are preserved in fossils as well as in living specimens. Within the palaearctic genus Testudo s.l., Eurotestudo was separated from two other inclusive genera, Agrionemys and Testudo s.s. In a cladistic analysis, Eurotestudo is distinguished by the autapomorphy of the narrowing vertebrals. Several more external characters (not derivable from fossils and thus omitted from the present cladistic analysis) also support the existence of the genus. Eurotestudo shares homoplastic characters with the two other lineages, the frequency and the evolutionary degree of which vary according to species in the two other genera. Further osteological characters and characters known only from living specimens are added to the osteological study. The characters are examined on a series of taxa chosen among the better known fossil forms from the Oligocene to the Present, Quaternary forms of the Eu. hermanni group included, and representative extant forms. Possible members of the three stems are examined. The autapomorphies of each stem are evidenced, the polarization of characters is tested and the homoplasies are detected. The hypothesis of a common origin for Testudo and Eurotestudo has best support in the present analysis.  相似文献   

18.
Eight new species of the family Cytheridae have been identified in the Upper Miocene deposits of the Turiec Basin (Slovakia), a small isolated intermountain depression. Six species are new - Euxinocythere aphroditae, E. delicata, E. lactea, E. minuscula, E. quadricostata, E. satyrica - and two are kept in open nomenclature. Their attribution to the genus Euxinocythere is based on arrangement of the hinge elements and of anterior marginal zone. This genus is known from brackish ostracod assemblages of the Paratethys and the Eastern Mediterranean while the species from the Turiec Basin are associated to fresh-water assemblages. The Euxinocythere have been found in littoral as well in deep limnic environment.  相似文献   

19.
The “Megalosaur” remains from Saint-Agnant (Charente-Maritime, France), reported as early as 1881 by Boissellier, are here described and figured for the first time. These bones, as well as a few additional specimens from the nearby locality of Soubise, belong in fact to an indeterminate sauropod. The stratigraphical position of these remains unambiguously indicates an infra-Cenomanian age. However, the presence in this area of continental deposits with Purbeckian and Wealden facies does not allow to decide between an earliest or late Early Cretaceous age.  相似文献   

20.
Female imagines, subimagines, eggs and larvae of Electrogena antalyensis (Kazanci & Braasch) from Turkey are described for the first time. The results of a thorough analysis of larvae, based on the standard set of diagnostic characters for the identification of Electrogena species, are reported. The peculiarity of several characters places E. antalyensis in an isolated position within the genus Electrogena.  相似文献   

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