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1.
A new lecanicephalidean species of Aberrapex Jensen, 2001 is described from the blue-spotted fantail ray Taeniura lymma (Forsskål) collected off the eastern coast of Sabah in Malaysian Borneo. This is the first record of a lecanicephalidean tapeworm from the island of Borneo and the first record of Aberrapex from this host species. A. manjajiae n. sp. is easily distinguished from its two congeners, A. senticosus Jensen, 2001 and A. arrhynchum (Brooks, Mayes & Thorson, 1981) Jensen, 2001, based on its overall smaller size (928–1,971 vs 1,485–6,333 and up to 3,350μm long, respectively) and fewer testes (10–19 vs 20–40 and 18–25, respectively). In addition, A. manjajiae n. sp. is readily distinguished from A. senticosus based on a more anteriorly positioned genital pore (76–85 vs 52–72% of proglottid length from posterior end) and its distal bothridial microthrix pattern. A. manjajiae n. sp. can be further distinguished from A. arrhynchum based on its smaller scolex (82–101 × 119–164 vs 177–186 × 233–326μm). The host distribution of Aberrapex is expanded from the Myliobatidae to include the Dasyatidae.  相似文献   

2.
 In contrast with previous reports, we observed high transpiration rates in mangrove trees. Maximum sap velocities and mean daytime sap flow rates were estimated from heat pulse velocity in entire, field grown trees of Avicennia cf. alba Blume and Rhizophora apiculata Blume. Results were within the range of values measured by identical techniques for trees in lowland dipterocarp and tropical heath forests with a similar climate in Brunei Darussalam (north Borneo). High stomatal conductance (400 mmol m –  2 s –  1) was also measured for well insolated leaves of A. cf. alba, with midday water potentials reaching about  – 3 MPa in both species. Received: 11 September 1996 / Accepted: 27 January 1997  相似文献   

3.
4.
 A new terapontid fish, Mesopristes iravi, is described based on 13 specimens collected on Iriomote Island, the Ryukyu Islands, Japan. This species closely resembles M. argenteus (Cuvier in Cuvier and Valenciennes, 1829) in having dark stripes on the body, but differs from that species in retaining the stripes even in adults (vs. stripes disappearing ontogenetically in the latter species), having the median stripe passing through the eye interrupted on the postorbital region (vs. continuous when the stripe present), a shorter fifth (longest) dorsal spine (14.6–19.7% SL vs. 18.0–22.2% SL), and a longer postorbital length (40.0–43.0% HL vs. 37.8–40.7% HL). Mesopristes iravi has been confused with M. argenteus in previous reports, and on the basis of the literature it may extend from the Ryukyu Islands, Japan, southward to Borneo, Indonesia, and New Guinea. Received: August 6, 2001 / Revised: February 24, 2002 / Accepted: March 7, 2002  相似文献   

5.
A new balitorid fish,Hemimyzon nanensis, is described from the Mae Nam Nan River basin, a tributary of the Chao Phraya River, in northern Thailand. This species is distinguishable from its congeners by the following unique combination of characters: pectoral fin with 9–11 simple and 10–12 branched, rays; pelvic fin with 3–4 (usually 3) simple and 8–9 (usually 9) branched rays; 59–63 total lateral line scales; distance between pelvic fin bases 8.1–9,6% SL.H. nanensis is the first species of the genus recorded outside China and Taiwan.  相似文献   

6.
The genetic structure of mangrove species is greatly affected by their geographic history. Nine natural populations of Ceriops tagal were collected from Borneo, the Malay Peninsula, and India for this phylogeographic study. Completely different haplotype compositions on the east versus west coasts of the Malay Peninsula were revealed using the atpB-rbcL and trnL-trnF spacers of chloroplast DNA. The average haplotype diversity (Hd) of the total population was 0.549, nucleotide diversity (θ) was 0.030, and nucleotide difference (π) was 0.0074. The cladogram constructed by the index of population differentiation (G ST) clearly separated the South China Sea populations from the Indian Ocean populations. In the analysis of the minimum spanning network, the Indian Ocean haplotypes were all derived from South China Sea haplotypes, suggesting a dispersal route of C. tagal from Southeast Asia to South Asia. The Sunda Land river system and surface currents might be accountable for the gene flow directions in the South China Sea and Bay of Bengal, respectively. The historical geography not only affected the present genotype distribution but also the evolution of C. tagal. These processes result in the genetic differentiation and the differentiated populations that should be considered as Management Units (MUs) for conservation measurements instead of random forestation, which might lead to gene mixing and reduction of genetic variability of mangrove species. According to this phylogeographic study, populations in Borneo, and east and west Malay Peninsula that have unique genotypes should be considered as distinct MUs, and any activities resulting in gene mixing with each other ought to be prevented.  相似文献   

7.
 A poorly known threadfin, Polynemus melanochir Valenciennes in Cuvier and Valenciennes, 1831, is redescribed (as P. melanochir melanochir) on the basis of a newly designated neotype and a large number of specimens. Polynemus melanopus Sauvage, 1881 and 3 species commonly regarded as valid, Galeoides microps Steindachner, 1869, P. borneensis Bleeker, 1857, and Trichidion hilleri Fowler, 1905, are all considered junior synonyms of P. m. melanochir. In addition, a new subspecies, P. melanochir dulcis, is described on the basis of 3 specimens. Polynemus m. dulcis differs from P. m. melanochir in having a greater snout length [7% of SL vs. mean 6% (range 5–6%) of SL in the latter] and shorter upper caudal-fin lobe length [35% (34–35%) of SL vs. 39% (35–44%) of SL]. The former is currently known only from Tonle Sap Lake, Cambodia, whereas the latter is known from the Mekong River (Cambodia and southern Vietnam) and Kalimantan (=Borneo; Malaysia and Indonesia). Received: September 27, 2001 / Revised: December 20, 2001 / Accepted: December 29, 2001  相似文献   

8.
In the geological research of the Holocene coastal deposits of The Netherlands, diatoms are used to reconstruct the sedimentary facies, palaeo-tide levels and salinity gradients during the deposition of the sediments. In this paper, the results of diatom research from 4 borings, taken from the early and middle Holocene deposits of central North Holland are presented. The oldest marine influenced sediments in the area are the deposits of the ‘Velsen layer’, a clay layer rich in organic matter and deposited about 8000–700014C years before present (BP) at a depth of 20–12 m below present mean sea-level. This clay layer was formed in a shallow, permanently submerged environment with a limited tidal influence (lagoonal or pond-like conditions). The salinity changed from brackish/freshwater to marine/brackish. The younger sandy and clayey sediments, formed about 7000–4500 BP at a depth of 16–3 m below present mean sea-level, are classified as ‘tidal channel’ and ‘interchannel’ deposits. It is argued, on the base of both diatom and non-diatom criteria, that the lower and middle parts of the interchannel deposits in the central area of the palaeo-tidal basin of North Holland were formed in a subtidal environment. The upper part of the interchannel deposits and the deposits at the fringe of the North Holland tidal basin were formed in the intertidal zone or, at the fringe of the basin, even in the supratidal zone. The salinity in the North Holland tidal basin during the sedimentation of the tidal channel and interchannel deposits was marine/brackish to marine. This study indicates that diatoms, besides their palaeoecological applications, have chronostratigraphical significance (on a regional scale). The diatomsCymatosira belgica andActinoptychus splendens appear to be a useful (eco)stratigraphical marker in the Holocene coastal deposits of The Netherlands and Belgium.  相似文献   

9.
A new balitord fish, Hemimyzon sheni n. sp. was collected from the Tar-Ju River basin, Taitung County, southeast Taiwan. The new endemic species can be distinguished from other congeneric species by a combination of the following features: (1) dorsal fin rays 3 + 8, pectoral fin rays 13+11 (total 24); (2) lateral-line scales 78–80 and predorsal scales 31–32; (3) somewhat pointed head shape; (3) small pelvic fin which does not extend to rear vertical of dorsal fin; (4) position of anus close to anal fin base; and (5) predorsal region with many very small light brown marks and unmarked pectoral fin. A diagnostic key to three nominal, endemic species of Hemimyzon from Taiwan is also provided in this paper.  相似文献   

10.
A new species of the viviparous fish genus Grammonus (Ophidiiformes: Bythitidae) is described, based on two ripe males, 32–55 mm SL. They were caught over a muddy bottom in a shrimp trawl at 70–119 m off Central Vietnam. A comparison with the nine hitherto described Grammonus species shows them to be clearly distinct from other species. Except for G. ater, G. minutus differs from all other species by having either more or fewer dorsal (75–76) and anal (54–55) fin rays. It differs from G. ater i.a. by having more pectoral fin rays (22–23 vs. 18–19).  相似文献   

11.
We studied rattan communities in four forest types in Borneo and Java to clarify the pattern of species diversity and vegetation structure. Within six plots of 4.82 ha in total, we found 42 rattan species in six genera with 4,736 stems (≥20 cm long). There was a significant positive correlation between rattans and trees in species diversity, decreasing in the order mixed dipterocarp (for rattans: Shannon–Wiener diversity index, H′ = 2.87–3.34) > alluvial (1.96) > lower montane (1.43) > peat swamp forests (1.34). This pattern coincided with the diversity of the regional flora. The density of rattan stems (ha–1) decreased in the order lower montane (5,997) > mixed dipterocarp (598–992) > alluvial (592) > peat swamp forests (162). The maximum height of rattans would be determined by the canopy height, rather than by the maximum tree height. The rattan stem volume ranged from 0.25 to 1.88 m3 ha−1 and was not correlated with the stem density. The cool montane climate seemed to decrease the maximum height of rattans, and a few small rattans made denser colonies. Swampy environments apparently suppressed the survival of non-climbing rattans strongly, but that of tall climbing rattans less so.  相似文献   

12.
Fluorescent in situ hybridization (FISH) with rRNA-specific oligonucleotide probes was used to assess the numbers and phylogenetic diversity of prokaryotic microorganisms in the water of small boreal lakes and peatland catchments of the swampy upper Volga basin. The abundance of bacterioplankton in lake water was found to vary from 1.6 to 8.7 × 106 cells ml−1, with the highest values detected in neutral eutrophic lakes. The total cell numbers in the peat of ombrotrophic bogs were 3.9–4.3 × 108 cells g−1 of wet peat. The proportion of bacteria identified by the group-specific probes decreased from 79–85% in neutral (pH 6.6–6.9) mesotrophic and eutrophic lakes to 65–69% in acidic (pH 4.4–5.5) dystrophic lakes and to 51–58% in the peat of acidic (pH 3.6–3.9) ombrotrophic bogs. The diversity of bacterial communities was highest in lakes with neutral water. These communities were dominated by members of the phylum Actinobacteria (31–44% of the total bacterial number), while the contribution of Alphaproteobacteria (16–19%), Bacteroidetes (6–16%), Betaproteobacteria (6–7%), Planctomycetes (2–8%), and Gammaproteobacteria (4–5%) was also significant. In acidic dystrophic lakes, Actinobacteria (25–35%) and Betaproteobacteria (25–34%) predominated, while peatland catchments were dominated by the Alphaproteobacteria (20–23%). The presence of acidobacteria and some planctomycetes common for bogs in the water of acidic dystrophic lakes, as well as the high proportion of bacteria (31–49%) that were not identified by the group-specific probes, suggest the impact of microbial processes in peatland catchments on the microbial composition of the receiving waters.  相似文献   

13.
Two new species of the sciaenid genusJohnius (Johnius) are described:J. trewavasae from Taiwan, Hong Kong, and Singapore, differs from all other congeners in having 24–27 dorsal soft rays, 5–6 scales above and 7–10 scales below the lateral line, 6–8 obtuse lower gill rakers, the last pleural rib on the 11th vertebra, and a shorter lower jaw (33.8–38.4% HL);J. latifrons from Thailand and Java is characterized by 25–29 dorsal soft rays, 7–9 scales above and 11–14 scales below the lateral line, 7–9 obtuse lower gill rakers, a wide interorbital width (26.1–30.6% HL), a small eye (16.7–26.4% HL), and a short, second anal spine (25.9–37.1% HL). Two related species,J. heterolepis Bleeker from “Suriname” andJ. cantori Bleeker from Malaya, are resurrected as valid West Pacific species of Johnius (Johnius).  相似文献   

14.
A new freshwater goby,Rhinogobius xianshuiensis sp. nov. was collected from the upper Mulan River basin of Xianyou County, Fujian Province, eastern China. The species is distinguished from related species in the region by 3–7 predorsal scales, 27 vertebrae, cephalic lateralis canals always always with 2 derived post-orbital pores (ε1) in adults, a reddish-brown vertical line below the anterior margin of the eye, and a red netlike pattern on the opercle. A key to species ofRhinogobius with higher vertebral numbers (27–29) from eastern China, Taiwan and Japan is provided.  相似文献   

15.
The dynamics of aseasonal lowland dipterocarp forest in Borneo is influenced by perturbation from droughts. These events might be increasing in frequency and intensity in the future. This paper describes drought-affected dynamics between 1986 and 2001 in Sabah, Malaysia, and considers how it is possible, reliably and accurately, to measure both coarse- and fine-scale responses of the forest. Some fundamental concerns about methodology and data analysis emerge. In two plots forming 8 ha, mortality, recruitment, and stem growth rates of trees ≥10 cm gbh (girth at breast height) were measured in a ‘pre-drought’ period (1986–1996), and in a period (1996–2001) including the 1997–1998 ENSO-drought. For 2.56 ha of subplots, mortality and growth rates of small trees (10–<50 cm gbh) were found also for two sub-periods (1996–1999, 1999–2001). A total of c. 19 K trees were recorded. Mortality rate increased by 25% while both recruitment and relative growth rates increased by 12% for all trees at the coarse scale. For small trees, at the fine scale, mortality increased by 6% and 9% from pre-drought to drought and on to ‘post-drought’ sub-periods. Relative growth rates correspondingly decreased by 38% and increased by 98%. Tree size and topography interacted in a complex manner with between-plot differences. The forest appears to have been sustained by off-setting elevated tree mortality by highly resilient stem growth. This last is seen as the key integrating tree variable which links the external driver (drought causing water stress) and population dynamics recorded as mortality and recruitment. Suitably sound measurements of stem girth, leading to valid growth rates, are needed to understand and model tree dynamic responses to perturbations. The proportion of sound data, however, is in part determined by the drought itself. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

16.
The antioxidant activity of eight edible species of Malaysian North Borneo seaweeds obtained from Sabah waters (Kudat, Tanjung Aru and Semporna) consisting of three red seaweeds (Eucheuma cottonii, E. spinosum and Halymenia durvillaei), two green seaweeds (Caulerpa lentillifera and C. racemosa) and three brown seaweeds (Dictyota dichotoma, Sargassum polycystum and Padina sp.) were determined. Methanol and diethyl ether were used as extraction solvent. The antioxidant activities were determined by two methods, TEAC (trolox equivalent antioxidant capacity) and FRAP (ferric reducing antioxidant power) assays. The total phenolic content of the extract was determined according to the Folin–Ciocalteu method and results were expressed as phloroglucinol equivalents. The methanolic extracts of green seaweeds, C. lentillifera and C. racemosa, and the brown seaweed, S. polycystum showed better radical-scavenging and reducing power ability, and higher phenolic content than the other seaweeds. The TEAC and FRAP assays showed positive and significantly high correlation (R 2 = 0.89). There was a strong correlation (R 2 = 0.96) between the reducing power and the total phenolic content of the seaweeds methanolic dry extracts. These seaweeds could be potential rich sources of natural antioxidants.  相似文献   

17.
Two new species of the cryptogonimid genus Parspina Pearse, 1920 are described from gymnotiform fishes of the Paraná River basin, P. carapo n. sp. from the banded knifefish Gymnotus carapo Linnaeus and P. virescens n. sp. from the glass knifefish Eigenmannia virescens (Valenciennes). Parspina carapo differs from P. virescens in the number of oral spines (32–39 vs 30–33) and their length (28–47 vs 16–28 μm), the distribution of tegumental spines and their anchorage, the types of sensory papillae on the body surface (three vs two types), the extent of body length posterior to the caeca (5 vs 13% of the total body length), the dimensions of the pars prostatica (52 × 34 vs 24 × 10 μm), and in the absence of a gonotyl (vs presence). Both P. carapo and P. virescens differ from P. bagre Pearse, 1920 and P. argentinensis (Szidat, 1954) in the number of oral spines (20–21 and 21–28 in the latter pair) and their length (28–32 and 35–60 μm), and in total body length. Additionally, the two new species differ from P. argentinensis in the arrangement of the vitelline follicles (one continuous band vs two groups on each side of the body) and in having a smaller pars prostatica (149 × 49 μm in the latter). Parspina carapo is the fifth intestinal helminth found in G. carapo, and P. virescens is the first found in E. virescens.  相似文献   

18.
Gerres macracanthus Bleeker, 1854, for many years having been explicitly or tentatively synonymized withG. filamentosus Cuvier, 1829, is redescribed as a valid species.Gerres macracanthus differs fromG. filamentosus in lacking vertical rows of dark ovoid spots on the body, having instead only indistinct vertical bands in both subadult and adult stages, in addition to shorter second and third anal fin spines (9.1–13.9% and 10.4–14.4% of standard length [SL] vs. 12.3–19.6% and 11.9–17.3% of SL), fewer ored lateral line scales (41–44 vs. 43–46) and fewer scales between the base of the 5th dorsal fin spine and the lateral line (4–5 vs. 4 1/2–5 1/2), and above and below the lateral line (5 1/2–6 1/2/9 1/2–10 1/2 vs. 6 1/2–7 1/2/10 1/2–11 1/2). AlthoughG. filamentosus has similarly, indistinct vertical bands on the body up to ca. 100 mm SL, specimens over ca. 100 mm SL develop diffuse ovoid spots in each vertical band. Furthermore,G. macracanthus is generally a smaller species, apparently attaining a maximum size of ca. 170 mm SL, compared with ca. 250 mm SL forG. filamentosus. Formerly known from the Philippines, Indonesia, New guinea, India and the Arabian Gulf,G. macracanthus is newly-recorded from Japan, China, the Gulf of Thailand, the Red Sea and South Africa. A lectotype and three paralectotypes are designated forG. macracanthus Bleeker, 1854, in addition to a neotype forG. filamentosus Cuvier, 1829.  相似文献   

19.
The distribution of Dreissena polymorpha in the northeastern part of the Kama River basin is limited to the area with the following geographic coordinates: 59°37′–54°00′ N and 57°10′–49°03′ E. The range of the zebra mussel is continuous along the Kama, Belaya, and Ufa rivers. Isolated populations of this mollusk exist in the Belaya and Vyatka river floodplains. The distribution of dreissena in the running waters of the Kama River basin is limited by the potamal conditions.  相似文献   

20.
In some localities of the upper reaches of the Kolyma River, the narrow-headed ant (Formica exsecta Nylander, 1846) has become the dominant species instead of a rare one during the last decade. To study this phenomenon, soil temperatures at a depth of 20 cm were measured in the winter of 2008–2009, near 11 nests of this species and in 11 more biotopes without nests, in the same localities where similar measurements had been carried out in the 1980s. The growth of minimum air temperatures by 2–2.5°C combined with increased snow cover since the end of the past century by the present time, has resulted in the minimal soil temperatures at a depth of 20 cm rising by 3–7°C. Being one of the least cold-resisting species of the genus (with limit of tolerance −12…−15°C), the narrow-headed ant has responded to winter warming of soils by increasing the variety of inhabited biotopes by 3–4 times, from 5–6 to 20–23 out of more than 43 examined; its abundance has grown sharply, to 130 nests per survey route 1300 m long and 20 m wide. Within the frame of the existing climate such deviations of soil temperature may occur once every 15–20 years. Therefore the changes observed may represent regular fluctuations. The prediction of population dynamics of F. exsecta in other parts of the subarctic belt within the permafrost zone should take into account the climatic specificity of the region which may considerably differ from that in adjoining territories.  相似文献   

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