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1.
A new orchid species, Liparis guangxiensis C. L. Feng & X. H. Jin, is described and illustrated from Guangxi, China. It is a widespread epiphyte in the limestone region at elevations of 200–1400 m in tropical evergreen forest. Liparis guangxiensis is similar to L. rhombea sharing a similar habit, a bifid lip and a column without wings, but differs by having a compressed peduncle, lateral sepals forming in ‘V’ below the lip and an oblong lip with a callus at the base. 相似文献
2.
A. J. Richardson ¶ G. Maharaj L. J. V. Compagno † R. W. Leslie ‡ D. A. Ebert § M. J. Gibbons 《Journal of fish biology》2000,56(3):552-576
Holohalaelurus regani was caught in 38% of the 3314 bottom trawls conducted during routine demersal surveys o. the South African west and south coasts from 1986 to 1999. An index of biomass for H. regani has increased on the west coast, from 1606 t in 1986–1993 to 3012 t in 1994–1999, despite c. 130 t being taken annually as by–catch in the demersal fishery. On the south coast, there has also been an increase over the same period, from 793 to 1350 t. Females and juveniles were generally found in shallower water (<300 m) than males, suggesting an inshore nursery area. Male H. regani become mature at 450–500 mm LT, whereas females become mature at 400–450 mm LT. There is reproductive activity throughout the year and fecundity appears to be high. This species is a generalist feeder, with the diet comprising teleosts, crustaceans and cephalopods. H. regani also scavenges offal opportunistically. Its high fecundity, the relative protection of females and juveniles in shallow water that is rarely trawled, its opportunistic diet and its robust nature that may allow it to survive after it has been discarded, have enabled H. regani to increase in numbers, despite indirect fishing pressure. 相似文献
3.
The eel genus Histiobranchus Gill occurs benthopelagically over the continental rise and abyss of the World Ocean, primarily beneath temperate and subpolar surface waters. Its generic status within the subfamily Synaphobranchinae is confirmed by comparison of the structure and topography of its cephalic sensory system and skeletal features with Synaphobranchus. At least three species of Histiobranchus are recognized: H. bathybius (panoceanic), H. bruuni (Tasman Sea and waters south-east of New Zealand) and H. australis (two geographical forms; South Atlantic and south-western Indian Ocean, and South Indo-West Pacific Oceans). Collections totalling 319 specimens of H. bathybius from the eastern North Atlantic (1790–5440 m depth) yielded a size range of 99–1370 mm total length ( L T ), with no apparent sexual dimorphism. Length–frequency distributions indicate a mode of juvenile fish at around 100–200 mm L T and a further two around 600–700 and 1300–1400 mm L T among adults. Generally smaller fish occur in shallower regions, although the size range is broad over the whole depth range. No apparent trend occurs in the size distribution with latitude over the range 17–54) N. Females outnumber males (1 male : 1·7 females) and both sexes are largely distinguishable from 300 mm L T . Ripening eggs occur in females from both adult length modes, with running ripe and spent females of very different size indicating iteroparity. 相似文献
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5.
MI YOON CHUNG CHONG-WOOK PARK ERIC R. MYERS MYONG GI CHUNG 《Botanical journal of the Linnean Society. Linnean Society of London》2007,153(1):41-48
Levels of allozyme variation and intrapopulation spatial genetic structure of the two terrestrial clonal orchids Liparis kumokiri , a self-compatible relatively common species, and L. makinoana , a self-incompatible rare species, were examined for 17 ( N = 1875) and four ( N = 425) populations, respectively, in South Korea. Populations of L. makinoana harboured high levels of genetic variation ( H e = 0.319) across 15 loci. In contrast, L. kumokiri exhibited a complete lack of allozyme variation ( H e = 0.000). Considering the lack of genetic variability, it is suggested that current populations of L. kumokiri in South Korea originated from a genetically depauperate ancestral population. For L. makinoana , a significant deficit of heterozygosity (mean F IS = 0.198) was found in population samples excluding clonal ramets, suggesting that pollen dispersal is localized, generating biparental inbreeding. The significant fine-scale genetic structuring (≤ 2 m) found in a previous study, in addition to the moderate levels of population differentiation ( F ST = 0.107) and the significant relationship between genetic and geographical distances ( r = 0.680) found here, suggests a leptokurtic distribution of seed dispersal for L. makinoana . Although populations of L. makinoana harbour high levels of genetic variation, they are affected by a recent genetic bottleneck. This information suggests that genetic drift and limited gene flow could be the main evolutionary forces for speciation of a species-rich genus such as Liparis . © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 153 , 41–48. 相似文献
6.
G. P. Semple 《Journal of fish biology》1986,29(4):499-506
Craterocephalus sp. nov. showed sexual dimorphism in body shape during the breeding season. Pairing occurred during daylight with a single release of eggs amongst submerged vegetation between sunrise and the early afternoon on the same day. The eggs were demersal, adhesive, spherical (0.87–0.96 mm diameter) and had 12 adhesive filaments (0.5–1.5 mm long) at the animal pole. Approximately 24 oil droplets (0.02–0.08 mm diameter) persisted throughout egg and larval development. Hatching occurred 155–160 h after spawning at 25–27° C.
The yolk-sac larvae were 3.85–3.95 mm notochord length at hatching and began feeding at the surface after absorption of the yolk (3–12 h after hatching). All fin rays were developed in 9.4 mm standard length fry, which moved from midwater to feed on the substrate. Aquarium reared fish first spawned at 30 mm s.L. when 165 days of age.
Features of Craterocephalus reproduction, as they relate to a specific survival strategy, are briefly discussed. 相似文献
The yolk-sac larvae were 3.85–3.95 mm notochord length at hatching and began feeding at the surface after absorption of the yolk (3–12 h after hatching). All fin rays were developed in 9.4 mm standard length fry, which moved from midwater to feed on the substrate. Aquarium reared fish first spawned at 30 mm s.L. when 165 days of age.
Features of Craterocephalus reproduction, as they relate to a specific survival strategy, are briefly discussed. 相似文献
7.
GEORGE POINARJR ALEX E.BROWN 《Botanical journal of the Linnean Society. Linnean Society of London》2002,139(2):125-132
Hymenaea mexicana sp. nov. is described in amber originating from mines of Chiapas, Mexico. The species is characterized by clawed showy petals with cordate bases and glabrous, verrucose ovaries with long hirsute hairs at their bases and margins on one side. This species is closely related to the extinct Hymenaea protera from Dominican amber, and together with it, is placed in the primitive section Trachylobium of the genus Hymenaea in the caesalpinoid legumes. The closest extant species to H. mexicana is H. verrucosa , a relict surviving in East Africa. These results challenge previous views that Mexican amber was produced by the South American species H. courbaril – H. intermedia , which belong to the advanced section of the genus. © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 139 , 125–132. 相似文献
8.
Ji-Dong Ya Dong-Liang Lin Zhou-Dong Han Lei Cai Zhi-Rong Zhang De-Ming He Xiao-Hua Jin Wen-Bin Yu 《Plant Diversity》2021,43(5):401
Liparis aureolabella and L. mengziensis, two new species from the karst region of southwestern China, and L. bingzhongluoensis, a new species from montane region in Yunnan, are described and illustrated. L. aureolabella is easily distinguished from its relatives by having abaxially purple leave with purple reticulate veins prominent adaxially, a lip auriculate at base, and falcate-lanceolate pollinia. Liparis mengziensis is closely related to L. petiolata and L. auriculata, but differs from them by having an ovate to broadly ovate leaf, purple lip and apex connate along the margins. Liparis bingzhongluoensis is similar to Liparis nanlingensis, but the new species is characterized by having a lip with two transparent ridges on its disc, longitudinally concave basal callus and triangular column wings. Phylogenetic analyses based on nuclear ribosomal ITS and plastid matK sequences showed that L. aureolabella and L. mengziensis are nested with L. petiolata or L. auriculata in a monophyletic clade. L. bingzhongluoensis is sister to a clade formed by L. nanlingensis, L. tsii, L. sasakii and L. krameri. Moreover, morphological comparisons strongly support that the three species as separated species newly to science. 相似文献
9.
A new orchid genus, Ypsilorchis Z. J. Liu, S. C. Chen & L. J. Chen, is established based on Ypsilor-chis fissipetala (Finet) Z. J. Liu, S. C. Chen & L. J. Chen (basionym: Liparis fissipetala Finet). The new genus differs from Liparis and its allies by having two granular-waxy pollinia each with a somewhat elastic caudicle, deeply bilobed petals and strongly crisped-margined leaves with an apical awn to 1 mm long. These features are an indication of its distant relation to the members of the subtribe Liparidinae, and thus a new subtribe, Ypsilor-chidinae Z. J. Liu, S. C. Chen & L. J. Chen, is proposed. 相似文献
10.
Distichia acicularis is described as a new species of Juncaceae. It occurs in the high Andes of Ecuador between 3200 m and 4200 m above sea level. Its closest relative is D. muscoides Nees & Meyen from which it is distinct through its narrow, linear, mucronate leafblades and its 1–3 mm long auricles at the junction of the leafsheath to the blade. 相似文献
11.
Light trap collections on oil and gas platforms in the northern Gulf of Mexico off Louisiana from 1995 to 1997 contained young of tessellated blenny Hypsoblennius invemar , freckled blenny Hypsoblennius ionthas , featherduster blenny Hypleurochilus multifilis , molly miller Scartella cristata and seaweed blenny Parablennius marmoreus , which are described. Interspecific differences were: number of dorsal, anal, pelvic and caudal fin elements; number of mandibular pores; presence or absence of canine teeth, hypural 5 and pectoral fin pigment; width of gill openings; length of preopercular spines (in larvae). Size at settlement differed among some taxa, but all five species settled within a narrow size window of c . 1·5 mm standard length ( L S ). Hypsoblennius invemar , H. ionthas , H. multifilis and S. cristata settled at mean sizes between 11·3 and 12·1 mm L S , whereas P. marmoreus settled at a mean size of 19·3 mm L S . Sexually dimorphic differences were consistently evident by 17–18 mm L S in all species but P. marmoreus . The two smallest blennies with external characters normally associated with sexual maturity were a 20 mm male and 21 mm female H. multifilis . Primary caudal fin rays began to bifurcate between 17·0 and 18·3 mm L S in H. invemar , H. ionthas , H. multifilis and S. cristata . Hypleurochilus multifilis displayed the external characteristics of being sexually mature at 20–21 mm L S . Thus, bifurcation of primary caudal fin rays was an indicator of approaching sexual maturity in H. multifilis and this may also be true in the other species studied. 相似文献
12.
Pellionia ronganensis sp. nov. (Urticaceae) is described and illustrated. Pellionia ronganensis resembles P. incisoserrata (H. Schroter) W. T. Wang, but is distinguished by leaves with obtuse theef, larger (6–10 mm long), linear stipules and tuberculate achenes. 相似文献
13.
CHARLES M. LEACH 《Botanical journal of the Linnean Society. Linnean Society of London》1985,91(1-2):233-243
An isolate of P. herbarum from beet seed failed to discharge ascospores in darkness but did so when exposed to light either continuously or cyclically (12 h light/12 h dark). When colonies with mature asci were subjected to a regime of alternating light and darkness for 54 days at a constant temperature of 20° C, ascospores were discharged over the entire period. Maximum discharge occurred on the 23rd day; few spores were liberated towards the end of the period. Light-induced spore discharge occurred over a wide temperature range (10–30° C) with the optimum being approximately 14–23° C. When light of different wavelengths (300 nm-infrared) was tested, only near-ultraviolet (310–330 nm) radiation stimulated ascospore discharge. Vertical height of ascospore discharge was also determined. When ascospores were trapped above colonies over a range of heights (2–80 mm), most spores were caught at 2 mm; none was caught at heights above 30 mm. The number of spores trapped at 30 mm was only 1.3% of the capture at 2 mm. 相似文献
14.
S. J. M. BLABER A. K. WHITFIELD 《Biological journal of the Linnean Society. Linnean Society of London》1977,9(3):277-284
Changes in the feeding ecology of juveniles (10–59 mm standard length) of eleven species of Mugilidae were investigated in south-east African estuaries. Adults of all species spawn in the sea and juveniles enter estuaries at a length of about 10 mm. In estuaries they change their feeding habits in the following sequence: zooplankton to zooplankton in the benthos (10–15 mm), zooplankton in the benthos to meiobenthos (10–20 mm), and meiobenthos to sand particles and associated microbenthos (15–25 mm). All species show a similar pattern of change but interspecific competition is probably prevented by the rapid switch to the adult diet of microbenthos and sand particles and because species enter estuaries at different times according to spawning periods. The juveniles seek shallow quiet water areas of estuaries and it is suggested that the change from being planktonic macrophagous carnivores to benthic microphagous omnivores can only take place in the estuaries of the region. Conditions in the inshore waters of the Indian Ocean in south-east Africa are probably too rough for substrate feeding by juvenile mullet. 相似文献
15.
Cameron KM 《American journal of botany》2005,92(6):1025-1032
Nuclear ITS and plastid matK sequences were collected for 71 taxa of Malaxideae (Orchidaceae). Resulting cladograms are highly resolved and well supported by jackknife analyses. These indicate that the traditional classification system of the tribe using characters primarily related to floral morphology does not reflect the evolutionary history of these taxa. Rather, the tribe is split into two major clades: one of terrestrial species and another of epiphytes. Within the epiphytic clade, taxa with laterally compressed leaves (Oberonia) are monophyletic, whereas the remaining taxa (Liparis pro parte) have elongate conduplicate leaves and form a paraphyletic grade of at least two additional monophyletic lineages. Within the terrestrial clade, taxa with plicate leaves (Liparis p.p. and Malaxis p.p.) clearly separate from taxa with conduplicate leaves (Liparis p.p. and Malaxis p.p.). Although further taxon sampling should take place before nomenclature is changed, it seems evident that Malaxideae will need to be divided into at least seven genera. Furthermore, the transition from epiphytic to terrestrial habit is documented to have occurred only once in Malaxideae, and the value of vegetative over reproductive features in classifying some groups of orchids is again demonstrated. 相似文献
16.
The osmoregulatory capabilities of juvenile striped mullet, Mugil cephalus L ., of three size-groups (20–29, 30–39 and 40–9 mm s.l.) were compared in a series of six salinities ranging from fresh water to full sea water. The two smaller size-groups were able to tolerate instantaneous transfer from the brackish water in which captured, to all salinities but fresh water, while the 40–69 mm group were tolerant of instantaneous transfer to all experimental salinities. At high environmental salinities, the osmotic regulatory capabilities improved with growth in size to an apparently definitive condition in fish of 40–69 mm s.l. The smallest of these individuals were estimated to be about 7.5 months old. The osmotic regulatory capability in waters of low salinity had reached a definitive state with the development of tolerance to such salinities. The ontogenetic pattern for Mugil cephalus is virtually identical to that of the Atlantic salmon, Salmo salar . 相似文献
17.
The ability of juvenile plaice (18–190 mm) to bury in sands varying in grain size from 0.062–2 mm was examined. For fish greater than approximately 30 mm in length the relationship between the proportion of the body covered with sand ( C ), total length ( L , mm) and grain size ( S , mm) can be estimated from the equation: logit C = 3.250 + 0.069 L – 6.771 S . Based on their performance in coarser sediments, fish smaller than approximately 30 mm did not bury as well as expected in the finest sediments (0.062 and 0.125 mm). 相似文献
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19.
A. W. H. Turnpenny 《Journal of fish biology》1983,23(3):321-325
Sustained swimming performance of juvenile sprat, S. sprattus (29–48 mm s.l.), and herring, C. harengus (46–58 mm) was measured in a laboratory flume over a range of salinities from 18 to 33%0 at water temperatures of 16–19°C. Critical swimming speeds (CSS) of both species, relative to body length, were similar, averaging 10–12 body lengths per second (bl s−1 ). There was no apparent relationship with salinity.
These swimming speeds are higher than values generally quoted in the literature for sustained swimming of sprat and herring (2–7 bl s−1 ) and it is concluded that the better performance found in this study was a function of improved fish handling techniques, and of the size of fish used since most other studies have dealt with larger, commercial sized fish. 相似文献
These swimming speeds are higher than values generally quoted in the literature for sustained swimming of sprat and herring (2–7 bl s
20.
This study has utilized the tools of lipid biomarker chemistry and molecular phylogenetic analyses to assess the archaeal contribution to diversity and abundance within a microbial mat and underlying sediment from a hypersaline lagoon in Baja California. Based on abundance of ether-linked isoprenoids, archaea made up from 1 to 4% of the cell numbers throughout the upper 100 mm of mat and sediment core. Below this depth archaeal lipid was two times more abundant than bacterial. Archaeol was the primary archaeal lipid in all layers. Relatively small amounts of caldarchaeol (dibiphytanyl glyceroltetraether) were present at most depths with phytanyl to biphytanyl molar ratios lowest (~10 : 1) in the 4–17 mm and 100–130 mm horizons, and highest (132 : 1) in the surface 0–2 mm. Lipids with cyclic biphytanyl cores were only detected below 100 mm. A novel polar lipid containing a C30 isoprenoid (squalane) moiety was isolated from the upper anoxic portion of the core and partially characterized. Hydrocarbon biomarker lipids included pentamethylicosane (2–10 mm) and crocetane (primarily below 10 mm). Archaeal molecular diversity varied somewhat with depth. With the exception of samples at 0–2 mm and 35–65 mm, Thermoplasmatales of marine benthic group D dominated clone libraries. A significant number of phylotypes representing the Crenarchaeota from marine benthic group B were generally present below 17 mm and dominated the 35–65 mm sample. Halobacteriaceae family made up 80% of the clone library of the surface 2 mm, and consisted primarily of sequences affiliated with the haloalkaliphilic Natronomonas pharaonis . 相似文献