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1.
The choanoflagellate genus Cosmoeca gen.n. is characterized by a very regular arrangement of rod-shaped costal strips, forming 9–12 longitudinal costae (each composed of 34 costal strips) and 2–3 transverse costae. Anteriorly the longitudinal costae attach the transverse costae at the joints between neighbouring transverse costal strips. Five species of Cosmoeca are described: norvegica sp.n. (type species; previously referred to as sp. "N"), C. ventricosa sp.n., (C. phuketensis sp.n., C. subulata sp.n. and C. ceratophora sp.n. Cosmoece ventricosa sp.n. is obviously part of from complex, the extent of which has not yet been fully explained. In this paper, three groups of specimens clearly related to C. ventricosa sp.n. are illustrated and briefly described ( C. ventricosa forms A. B, C). Form A appears to be identical to Pleurasiga orculaeformis Schiller, 1925, sensu Leadbeater. 相似文献
2.
Ichthyological Research - A new species of the genus Acropoma, A. musorstom sp. nov. is described based on four specimens (126.3–143.0 mm in standard length: SL) collected from Vanuatu and... 相似文献
3.
A survey of xeniid octocorals was carried out in the waters off Southwestern Thailand in September, 2007. Microscopic investigation of the colonies revealed that three specimens belonged to the genus Ovabunda. Gross morphological examination is presented here accompanied by scanning electron micrographs of the sclerites. Molecular phylogenetic analysis showed identical genotypes at mtMutS, COI, and 28S rDNA for all three specimens and supports their generic assignment. Colony size and shape, sclerite size, and pinnule arrangement differ from nominal species of Ovabunda and thus a new species, O. andamanensis is introduced here. This work also presents a new eastern geographical record for the genus Ovabunda. 相似文献
4.
Natinee Sukramongkol Kotaro Tsuchiya Susumu Segawa 《Reviews in Fish Biology and Fisheries》2007,17(2-3):237-246
Estimated age, hatching date and sexual maturation were investigated for the loliginid squids Loligo duvauceli and L. chinensis, the commercially important neritic species in the Andaman Sea of Thailand. The specimens caught by commercial bottom-trawl
in Phang-nga Bay and southern area off Phuket Island were obtained monthly from Phuket fish landing between April and August
2005. Age was estimated based on the counting of statolith increments from a total of 329 individuals of L. duvauceli (ML ranges from 41 to 224 mm) and 116 individuals of L. chinensis (ML ranges from 42 to 186 mm). The estimated age ranged from 41 to 161 and 67 to 158 days old for L. duvauceli and L. chinensis, respectively. The length–weight relationships differed among sexes and the sexual dimorphism was expressed as mature females
having a greater body weight than males of the same length. Males showed a wide range of maturity size possibly because of
the seasonal change in size at maturity. The results of the back calculation for the hatching date of individuals fell between
November 2004 and June 2005 which suggests that L. duvauceli and L. chinensis hatch continuously and recruit to the fishing ground for a relatively short period with a shorter lifespan than expected. 相似文献
5.
Carin Jantzen Gertraud M. Schmidt Christian Wild Cornelia Roder Somkiat Khokiattiwong Claudio Richter 《PloS one》2013,8(11)
Coral reefs are facing rapidly changing environments, but implications for reef ecosystem functioning and important services, such as productivity, are difficult to predict. Comparative investigations on coral reefs that are naturally exposed to differing environmental settings can provide essential information in this context. One prevalent phenomenon regularly introducing alterations in water chemistry into coral reefs are internal waves. This study therefore investigates the effect of large amplitude internal waves (LAIW) on primary productivity in coral reefs at the Similan Islands (Andaman Sea, Thailand). The LAIW-exposed west sides of the islands are subjected to sudden drops in water temperature accompanied by enhanced inorganic nutrient concentrations compared to the sheltered east. At the central island, Ko Miang, east and west reefs are only few hundred meters apart, but feature pronounced differences. On the west lower live coral cover (-38 %) coincides with higher turf algae cover (+64 %) and growth (+54 %) compared to the east side. Turf algae and the reef sand-associated microphytobenthos displayed similar chlorophyll a contents on both island sides, but under LAIW exposure, turf algae exhibited higher net photosynthesis (+23 %), whereas the microphytobenthos displayed reduced net and gross photosynthesis (-19 % and -26 %, respectively) accompanied by lower respiration (-42 %). In contrast, the predominant coral Porites lutea showed higher chlorophyll a tissues contents (+42 %) on the LAIW-exposed west in response to lower light availability and higher inorganic nutrient concentrations, but net photosynthesis was comparable for both sides. Turf algae were the major primary producers on the west side, whereas microphytobenthos dominated on the east. The overall primary production rate (comprising all main benthic primary producers) was similar on both island sides, which indicates high primary production variability under different environmental conditions. 相似文献
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8.
The 2004 tsunami left a discontinuous pattern of destruction in the reefs along Andaman Sea coast of Thailand. Here, a comparative
assessment of coral recruitment was carried out to assess differences in recovery between damaged and undamaged sites in near-shore
fringing reefs 1 and 3 years after the tsunami. Settlement plates showed high frequencies of coral spat after 4 months (<17
spat tile−1) in both, damaged and undamaged locations. Field surveys carried out 3 years after the tsunami on natural substrate confirmed
that tsunami damage did not suppress recruitment in damaged sites relative to no impacted controls. New and stable settlement
space along with unabated larval supply supported post-tsunami recruit densities up to 7.2 m−2 year−1. Mean recruit densities were found at the level of post-storm situations with rapid recovery success, suggesting that the
duration of disturbance, degree of sorting and, hence, stability of coral rubble is a key determinant of recruitment success.
Low regeneration success of some species e.g. branching acroporids and rebounding tourism industry at sites like Patong and
partly around the Phi Phi Islands (dense carpets of filamentous algae) led to the assumption of selectivity and eventually
to an alternation of the coral community even though live coral cover might be recovered soon. 相似文献
9.
A new acropomatid fish, Acropoma
argentistigma, is described on the basis of six specimens (59.0–107.5 mm in standard length) from the Andaman Sea, off southern Thailand
(Phuket Island). The new species is distinguished from all other congeners by the combination of the following characters:
a short U-shaped luminous gland, 16–18 gill rakers, anus situated about midway along depressed pelvic fin, proximal radial
of first anal fin pterygiophore with a trough, a single row of well-developed conical teeth on the lower jaw, and head length
40.0–41.1% of standard length.
Received: April 17, 2001 / Revised: April 15, 2002 / Accepted: May 7, 2002 相似文献
10.
A new platycephalid,Thysanophrys papillaris, is described on the basis of six specimens (78–121 mm SL) collected from the Andaman Sea and off northern Australia (Timor
and Arafura Seas). This new species can be distinguished from other congeners by the following combination of characters:
presence of a single short papilla on upper surface of eye, longer snout, smaller body scales. 11 second dorsal-fin rays and
12 anal-fin rays, presence of four or more suborbital spines usually, branched short iris lappet, ctenoid lateral-line scales
and interopercle not extended posteroventrally. 相似文献
11.
Ammonium adsorption in sediments of a tropical mangrove forest (Thailand) and a temperate Wadden Sea area (Denmark) 总被引:5,自引:0,他引:5
Dimensionless ammonium adsorption coefficients (K) were determined for tropical mangrove forest sediments and temperate Wadden
Sea sediments. The K values were obtained from ammonium adsorption isotherms of KCl (2 M) extractable ammonium versus dissolved
ammonium in the porewater; relationships that can be described by a linear model. Linearity was evident even at low porewater
concentrations for mangrove sediment, according to isotherms based on KCl extractions on untreated sediment profiles. K-values
were low in mangrove forest sediments (0.04–0.10), and higher in Wadden Sea sediments (0.17–1.12). The vertical range in K-values
was larger at the vegetated sites, with highest values in subsurface sediments, which suggests differences in quantity and
quality of the fine organic and inorganic fractions. The low ammonium adsorption in the mangrove sediments can be explained
by a higher concentration of competitive cations, especially iron, in this iron-rich environment. The low adsorption of ammonium
in mangrove sediments and vegetated surface sediment of the Wadden Sea was negatively related to the organic content of the
sediments, which is in contrast to findings for other marine sediments. We suggest that organic material may have a diluting
effect on the exchange capacity in fine-grained sediments, and that organic coatings may block ion exchange sites on clay
surfaces. Thus, there may be a organic-rich ‘wetland’ versus organic-poor ‘sediment’ effect.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
12.
Ferretti Ornella Niccolai Ilaria Bianchil Carlo Nike Tucci Sergio Morri Carla Veniale Fernando 《Hydrobiologia》1989,176(1):171-187
Since 1980, a large program of environmental studies has been carried out along the central part of the eastern Tyrrhenian Sea, and its adjacent shoreline. The general sedimentological, biological and geochemical characteristics of this continental shelf area have been reported elsewhere (Zurlini & Damiani, 1983). In this paper, the processes responsible for the transport of terrigenous particulate matter are considered together with the influence of this particulate matter on the benthic communities of the area.Two rivers, the Garigliano to the north and the Volturno to the south, determine the extent of major environmental sub-zones in the gulf of Gaeta. The first, influenced by the Garigliano River, is restricted to the northern and inner part of the gulf, where morphological and hydrodynamical conditions favour the accumulation of suspended matter; benthic communities are stressed, mainly due to high rates of siltation. The second sub-zone is mainly influenced by the Volturno River, which affects a very large area, spreading both north and south along the coast and up to 15 km offshore.Measured levels of trace elements are considered to be close to natural concentrations. Anthropogenic contamination appears to be related to the effects of agricultural practices on the alluvial plains and to the presence of urban settlements. 相似文献
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Justine Jackson‐Ricketts R. Iliana Ruiz‐Cooley Chalatip Junchompoo Surasak Thongsukdee Atichat Intongkham Santi Ninwat Kongkiat Kittiwattanawong Ellen M. Hines Daniel P. Costa 《Marine Mammal Science》2019,35(2):492-521
Irrawaddy dolphins (Orcaella brevirostris) are threatened, little‐known cetaceans primarily jeopardized by fishing gear entanglement. Information regarding life history, foraging ecology, and movement are crucial to determine management units and conservation regions. This is the first analysis of the ontogenetic changes in diet and habitat of Irrawaddy dolphins from the Gulf of Thailand and the Andaman Sea using stable isotopes from skin and teeth. Results suggest limited age and sex structure indicated by weak ontogenetic and sexual variability in δ15N and δ13C in teeth. Significant variation in δ13C and δ15N values were observed between three Gulf regions and the Andaman Sea, indicating distinct regional groups. Isotope mixing models run on soft tissues from the eastern Gulf revealed a diet based primarily on fishes and secondarily on crustaceans, suggesting overlap with fishery targets. Conservation strategies that focus on reducing regional competition with humans and bycatch mortality are proposed. Fishing gear improvements and monitoring of fishing operations are a potential immediate response to reduce anthropogenic impact. 相似文献
15.
Tobias Pfingstl Andrea Lienhard Satoshi Shimano Zulfigar Bin Yasin Aileen Tan Shau‐Hwai Sopark Jantarit Booppa Petcharad 《Journal of Zoological Systematics and Evolutionary Research》2019,57(1):91-112
This study demonstrates for the first time the presence of marine‐associated mites in the Andaman Sea and Strait of Malacca and reveals a relatively high diversity of these taxa with six species from two different families: Selenoribatidae and Fortuyniidae. Indopacifica, a new genus of Selenoribatidae, is described from Thailand and Malaysia, with two new species, Indopacifica pantai n. sp. and Indopacifica parva n. sp. The genus is characterized by the unique combination of following characters: lacking lamellar ridges, incomplete dorsosejugal suture, fourteen pairs of notogastral setae, and presence of epimeral foveae. A phylogenetic reconstruction based on 18S ribosomal RNA sequences clearly confirms the distinctness of the new genus Indopacifica and places it close to the genus Rhizophobates. The lack of molecular genetic data of possible relatives impedes a clear assessment, and hence, we emphasize the need for further combined approaches using morphological and molecular genetic sequence data. All species show wide distribution areas within this geographic region suggesting that these taxa are good dispersers despite their minute size and wingless body. Molecular genetic data demonstrate recent gene flow between far distant populations of I. pantai n. sp. from the coasts of Thailand and two islands of Malaysia and hence confirm this assumption. The seasonally changing surface currents within this geographic area may favor hydrochorous dispersal and hence genetic exchange. Nevertheless, morphometric data show a slight trend to morphological divergence among the studied populations, whereas this variation is suggested to be a result of genetic drift but also of habitat differences in one population of Alismobates pseudoreticulatus. 相似文献
16.
A total number of 40 potentially toxic microalgae and 5 taxa causing discolorations have been identified along the coasts of the Campania region (South Tyrrhenian Sea, Mediterranean Sea). This number is based on results of over 20 years of research at a coastal station in the Gulf of Naples, 4 years of monitoring activity along the Campania coasts and of a series of scattered and sporadic observations. Several species of the recently erected genera Karenia and Takayama are reported for the first time in the area. Information on the period of highest abundances or most probable period of occurrence indicates the late spring and summer as the periods of maximum risk of harmful events. Despite the variety of potentially toxic species, no human health problems nor fish kills have ever been recorded in Campania. The reasons for this apparent paradox are probably to be found in the ecological factors that regulate the abundance, toxicity and spatial distribution of the potentially harmful species and reflect as well the relatively low number of aquaculture plants in the area. 相似文献
17.
Less than 1% of Staphylinidae are known to be confined to coastal habitats. To explore the origins of coastal colonization within the tribe Athetini Casey, we present a revised molecular phylogeny. The dataset comprised partial mitochondrial COI, COII, 16S rDNA, NADH1, partial nuclear 18S rDNA and 28S rDNA. We chose a total of 95 species in 51 genera, including 14 coastal species in eight genera and 21 outgroup species from other aleocharine tribes. The concatenated dataset was analysed simultaneously by both parsimony‐ and model‐based (Bayesian and maximum likelihood) methods. The tribe Athetini was not supported as a monophyletic group, but together with the tribes Tachyusini, Ecitocharini and Hygronomini did form a monophylum. The ecological association of species with a coastal habitat was mapped onto a phylogeny to assess the evolution of habitat specialization in the Athetini lineage. The results reveal that five independent origins of coastal colonization have occurred throughout the tribe Athetini: (a) Osakatheta + Adota minuta + coastal Atheta (Badura) (clade A); (b) Adota (clade B); (c) Pontomalota + Tarphiota + Thinusa (clade C); (d) Iotarphia (clade D); and (e) Psammostiba (clade E). The low species number of the coastal Athetini compared with the entire Athetini lineage indicates that coastal habitats are harsh environments and so only a few species were able to colonize this habitat. The following changes in classification are proposed: (a) Ad. minuta Lee and Ahn is removed from the genus Adota and tentatively included in Atheta (Badura); (b) The genus Saphocallus Sharp is transferred from Athetini to Geostibini. 相似文献
18.
The aquifer system of Doñana (SW Spain) represents the most important freshwater source in the Doñana Natural Area. Its spatiotemporal dynamics favours the hydrological connection between surface and subsurface ecosystems, and promotes matter fluxes among the different terrestrial and aquatic systems present here. This aquifer has been intensively studied from a hydrogeological point of view but little is known from an ecological perspective. In order to understand the ecological roles played by microbial communities in this system, we conducted a long-term seasonal study of bacterial abundance, cell biomass, bacterial biomass and functional activities over a 2-year period. Bacterial abundance ranged between 2.11 ± 1.79 × 105 and 8.58 ± 6.99 × 107 bacteria mL−1 groundwater, average cell biomass was estimated to be 77.01 ± 31.56 fgC and bacterial biomass varied between 8.99 ± 4.10 × 10−2 and 5.65 ± 0.70 µgC mL−1 . Iron-related bacteria showed the highest activities among the functional groups studied. Moreover, among the variables that usually control spatial distributions of microbial communities in aquifer systems, depth did not have a relevant effect on this aquifer, at least in the range of depths studied, but grain size, probably due to its direct effects on hydrogeological parameters, such as permeability or porosity, appeared to exert moderate control, principally in terms of bacterial abundance. Finally, significant seasonal differences in the means of these microbiological variables were also observed; temperature seems to be the main factor controlling the temporal distribution of microbial communities in this aquifer system. 相似文献
19.
A new species Miliusa jainii (Annonaceae) from South Andamans, India, is described and illustrated. 相似文献
20.
Nishizawa T Savas H Isidan H Ustündağ C Iwamoto H Yoshimizu M 《Applied and environmental microbiology》2006,72(4):2373-2378
Viral hemorrhagic septicemia (VHS) is one of the most serious fish viral diseases for cultured rainbow trout (Oncorhynchus mykiss), although VHS virus (VHSV) seems to be ubiquitous among marine fishes. In the present study, VHSV isolation was performed with free-living and cultured turbot (Psetta maxima) in the Trabzon coastal area of the Black Sea to evaluate participation of VHSV in mass mortalities of seed-produced turbot larvae. VHSV was detected in 14 of 66 free-living spawners (positive ratio, 21.2%), 1 of 65 free-living immature fish (1.5%) and 7 of 40 cultured brood stock (17.5%), respectively. Based on a partial glycoprotein gene nucleotide sequence, Turkish VHSV isolates were classified into the class I-e of genotype I and were the most closely related to the GE-1.2 isolate (>98% identity), which was found >20 years ago in Georgia. Thus, it was revealed that Turkish VHSV isolates were not introduced from European countries, it could be an indigenous type of VHSV distributing in the Black Sea environment. In pathogenicity tests, the Turkish isolates did not induce mortality in turbot larvae and rainbow trout fingerlings. Mass mortalities at a rate of approximately 90% occurred in turbot larvae produced by experimental seeding, although VHSV was not detected in any dead fish. Thus, it was concluded that mass mortality in the seed-produced turbot larvae was not caused by VHSV infection. 相似文献