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1.
喀斯特典型地区烟管荚蒾AM真菌多样性研究 总被引:1,自引:0,他引:1
烟管荚蒾是喀斯特地区灌木丛的主要组成植物。以茂兰喀斯特森林为采样地点,对烟管荚蒾AM真菌进行了分离、鉴定与多样性分析,并对优势菌种进行初步的接种研究。结果表明:烟管荚蒾根系的菌根侵染率为82.1%,从根际土壤分离到AM真菌2属16种,球囊霉属(Glomus)7种,无梗囊霉属(Acaulospora)9种。优势种为根内球囊霉(Glomus intraradices)、皱壁无梗囊霉(Acaulospora rugosa)和刺无梗囊霉(A. spinosa)。优势菌种接种紫花苜蓿(Medicago sativa),促生作用明显,并显著提高了SOD、POD和CAT酶活性。该研究对于探讨喀斯特地区AM真菌的多样性与独特性,筛选优良的宿主植物和与之高效共生的AM真菌具重要意义。 相似文献
2.
To provide an overview for the State Pollution Control Commission of NSW, 102 lakes were visited throughout the state during the 1988–9 summer to ascertain their ecological condition. The sites chosen covered a spectrum of geomorphic types in approximate proportion to their perceived relative abundance. Field work concentrated on some physicochemical parameters and on zooplankton and littoral invertebrates. A summary of these features of the lakes of NSW is given.The most widespread problem is eutrophication, though for many lakes changes in trophic status could be part of wider changes in lakes since European settlement. A significant number of lakes suffer eroded shorelines and sedimentation. The introduced mosquito fish, Gambusia affinis, is associated with decreased diversity mainly in coastal lakes where also alien plants may be pestiferous. A few lakes in western areas have their flooding regime altered, while a number in the east are drained. With few exceptions there are no management programs to improve the conservation status of degraded lakes in NSW. 相似文献
3.
Molecular diversity of soil basidiomycete communities in northern-central New South Wales, Australia 总被引:1,自引:0,他引:1
David J. Midgley Jennifer A. Saleeba Michael I. Stewart Alice E. Simpson Peter A. McGee 《Mycological Research》2007,111(3):370-378
Basidiomycete communities were profiled using terminal RFLP (TRFLP) and amplified ribosomal DNA restriction analysis (ARDRA) approaches at seven field sites under differing land use in northern-central New South Wales (NSW), Australia. TRFLP data indicated greater basidiomycete species richness at sites with natural vegetation. Sixty-seven basidiomycete ARDRA-types were detected. Various putatively ectomycorrhizal fungi were detected at all sites with native vegetation. Most ectomycorrhizal taxa had affinities to the genus Tomentella, while two Pisolithus taxa and putatively ectomycorrhizal Cantharellales taxa were also detected. Although soils under woodland or grassland communities supported a range of putatively saprotrophic taxa, only members of the Ceratobasidiales were detected in soils under agricultural land use. This study is the first investigation of fungal communities in soils of northern-central NSW, Australia. 相似文献
4.
A new genus of alonine chydorid cladocerans from athalassic saline waters of New South Wales,Australia 总被引:3,自引:3,他引:0
David G. Frey 《Hydrobiologia》1991,224(1):11-48
A new genus (Celsinotum) and three new species are described from intermittent athalassic saline waters in the Paroo region of northwest New South Wales, which have TDS varying from 2.8 to 14.0 g l-1. The species are large, thin, high-bodied, and have a pronounced keel on the shell but not on the head. The marginal armature of the postabdomen consists entirely of clusters of fine spinules. Most strikingly, the males have 12 terminal aesthetascs on the antennule, and in addition have 5 or 6 equally long accessory aesthetascs arising laterally. Alona taraporevalae from India presumably also has this character, but a comparison of the two species indicates they are not closely related.The taxa bear a general similarity to Alona diaphana from Australia, but a close comparison shows that they, too, are unrelated. A. diaphana has a prominent spine arising from the basal segment of the antennal exopod, the two IDL (= inner distal lobe) setae on trunklimb I have a much coarser setulation distally than in Celsinotum, and on the postabdomen the postanal portion is always considerably longer than the anal, and the marginal armament consists of single setae distally and clusters of only a few setae proximally. Besides, the species is smaller, the body is wider and less high, and the shell although weakly ridged is not keeled. The male has 9 terminal aesthetascs and no accessory lateral ones.In athalassic saline waters around the world the number of anomopod species declines negative exponentially in relation to salinity. Many of the freshwater species persist into the 3 to 10 range without any difficulty, some occur in abundance up to 30, and a few even extend into the hypersaline range. Chydorids, though, except for a very few species, do not tolerate salinities higher than about 15, and none of them seem adapted to these salinities and confined to them. Celsinotum, though, possibly is so adapted, as it did not occur in other basins of the region with lower salinities, and it is not presently known from other regions.Having different but closely related congeneric taxa in nearby lakes of the same region seems surprising. The three species of Celsinotum are very similar in most details of morphology, but they vary significantly in body proportions, the number of denticle clusters on the postanal portion of the postabdomen, and in such seemingly minor details as the amount of expansion of the labral plate. Such taxonomic differentiation, which has been observed in other groups of organisms as well, is believed to have arisen from the extreme temporal isolation of these waterbodies, those in the Paroo region normally containing water only once every 5 to 20 years. 相似文献
5.
Dissolved and particulate organic carbon in two wetlands in southwestern New South Wales,Australia 总被引:1,自引:0,他引:1
Concentrations of dissolved (DOC) and particulate organic carbon (POC) in two billabong wetlands (Murrumbidgil Swamp and Lake
Merrimajeel) in inland temperate Australia were positively correlated with leaf fall from river red gums Eucalyptus camaldulensis (DOC and POC in Murrumbidgil Swamp), phytoplankton productivity (DOC in Murrumbidgil Swamp, DOC and POC in Lake Merrimajeel),
and with biomass of aquatic macrophytes (DOC in the two wetlands). DOC correlated with water level at both sites. Mean concentrations
of DOC (Murrumbidgil Swamp, 36.0 gm-3; Lake Merrinmajeel, 27.5 g m-3) and POC (15.0 g m-3; 15.5 g m-3) were high compared with other water bodies worldwide, although average for wetlands. The relatively high concentrations
of DOC and POC in the study wetlands appear to be the result of their high rates of plant production, and input of leaves
from river red gums. 相似文献
6.
Influence of arbuscular mycorrhizae and Rhizobium on nutrient content and water relations in drought stressed alfalfa 总被引:4,自引:0,他引:4
The objective of this research was to study the effect of drought on nutrient content and leaf water status in alfalfa (Medicago sativa L. cv Aragón) plants inoculated with a mycorrhizal fungus and/or Rhizobium compared with noninoculated ones. The four treatments were: a) plants inoculated with Glomus fasciculatum and Rhizobium meliloti 102 F51 strain, (MR); b) plants inoculated with R. meliloti only (R); c) plants with G. fasciculatum only (M); and d) noninoculated plants (N). Nonmycorrhizal plants were supplemented with phosphorus and nonnodulated ones with nitrogen to achieve similar size and nutrient content in all treatments. Plants were drought stressed using two cycles of moisture stress and recovery. The components of total leaf water potential (osmotic and pressure potentials at full turgor), percentage of apoplastic water volume and the bulk modulus of elasticity of leaf tissue were determined. Macronutrient (N, P, K, Ca, S and Mg) and micronutrient (Co, Mo, Zn, Mn, Cu, Na, Fe and B) content per plant were also measured. Leaves of N and R plants had decreased osmotic potentials and increased pressure potentials at full turgor, with no changes either in the bulk modulus of elasticity or the percentage of apoplastic water upon drought conditions. By contrast, M and MR leaves did not vary in osmotic and turgor potentials under drought stress but had increased apoplastic water volume and cell elasticity (lowering bulk modulus). Drought stress decreased nutrient content of leaves and roots of noninoculated plants. R plants showed a decrease in nutrient content of leaves but maintained some micronutrients in roots. Leaves of M plants were similar in content of nutrients to N plants. However, roots of M and MR plants had significantly lower nutrient content. Results indicate an enhancement of nutrient content in mycorrhizal alfalfa plants during drought that affected leaf water relations during drought stress. 相似文献
7.
Arbuscular mycorrhizae affect grassland plant community composition and host plant nutrient uptake, and can mediate shifts in competitive outcome between plant species. Centaurea maculosa, an invasive forb from Eurasia, dominates more than 4 million hectares in the Rocky Mountain region of North America. We examined the role of AM for phosphorus (P) acquisition from a distant source for C. maculosa and Festuca idahoensis, a native bunchgrass. Plants were grown individually in pots divided by a barrier that either excluded plant roots and AM hyphae, or only plant roots. In the half of the pot without a plant, 1 of 3 P treatments was applied: no P, phosphate rock (PR) or triple superphosphate (TSP), applied at a rate of 144 mg P kg–1 soil. After 14 weeks of growth, C. maculosa was twice as large as F. idahoensis, and neither species biomass was affected by barrier type. Phosphorus fertilizer, and especially PR, moved across the barrier to the plant side of the pot. Tissue P concentration for C. maculosa was highest with the PR treatment, and was not affected by the barrier type. In contrast, F. idahoensis tissue P concentration did not vary with barrier or P treatments. There was more AM extra radical hyphae (ERH) associated with C. maculosa than F. idahoensis, suggesting that C. maculosa provides more carbon for the AM fungi, resulting in greater ERH production, ERH soil exploration and potential for soil nutrient pool exploitation. Although not tested in this study, differences between host plants may be the result of different physiological characteristics of the host plant or differences in AM fungal species that colonize the invader, with different fungal species accessing P from different distances. 相似文献
8.
The stylochid flatworm, Imogine mcgrathi was confirmed as a predator of the pteriid oyster Pinctada imbricata. Occurring at an average of 3.2 per oyster spat collector bag, the flatworms were found to consume oysters at a rate of 0.035–0.057 d–1 in laboratory trials. Predation was affected by flatworm size with larger worms capable of consuming larger oysters and of consuming greater dry weights of oyster flesh. Irrespective of flatworm size, predation was generally confined to oysters less than 40 mm in shell height. Although all predation occurred at night, shading flatworms during the day did not significantly increase the rate of predation, but there were significant increases in the dry weight of oyster meat consumed. As a means of controlling flatworm infestations, salt, brine baths (250 g kg–1) and freshwater baths were effective in killing I. mcgrathi. The ease of use of hyper- or hyposaline baths then encouraged assessments of I. mcgrathi halotolerance. The flatworms were exposed to solutions ranging in salinity from 0 to 250 g kg–1for periods of from 5 min to 3 h. Despite showing both behavioural and physiological signs of stress, I. mcgrathi survived the maximum exposure time of 3 h at salinities in the range 7.5–60 g kg–1, inclusive. Beyond this range, the duration of exposure tolerated by flatworms decreased until 0 and 250 g kg–1, at which the flatworms no longer survived the minimum tested exposure of 5 min. Thus, despite the significant impact of other stylochids on commercial bivalves, at their current prevalence, I. mcgrathi can be controlled by exposing them to hyper- and hyposaline baths for the culture of P. imbricata in Port Stephens, NSW, Australia. 相似文献
9.
M. T. McHenry B. R. Wilson J. M. Lemon D. E. Donnelly I. G. Growns 《Plant and Soil》2006,285(1-2):245-255
Dense White Cypress Pine (Callitris glaucophylla J. Thompson and L.A.S. Johnson) regrowth occurs frequently across previously cleared landscapes in New South Wales (NSW), and is thought to adversely affect agricultural production and to cause land degradation. The NSW Native Vegetation Act (2003) requires that management of native vegetation including pre-1990 regrowth must ‘improve or maintain’ site condition, yet there is currently limited information regarding techniques for the optimum management of C. glaucophylla in this regard. We conducted a preliminary study to examine floristic composition, soil condition (to 50 cm) and carbon storage under ‘Dense’ (dense regrowth), ‘Thinned’ (dense regrowth thinned 2000/2001) and ‘Un-colonised’ (pasture not yet recolonised by C.␣glaucophylla) plots on private lands in NSW. Reduced tree density from thinning resulted in increased biomass of the remaining individual trees. Un-colonised plots had significantly more groundcover than thinned plots, which had significantly more groundcover than dense plots. Differences in plant diversity however, were explained by site factors rather than land use. Soils in the dense plots were the most acid but soil pH was significantly higher in thinned plots and pH was highest in soil of the un-colonised plots. Mean values for carbon, nitrogen, sulphur and extractable phosphorus varied among sites, although each were significantly more abundant in the mineral soil of dense and thinned plots compared with un-colonised plots, suggesting that thinning had had a minimal effect on the soil parameters assessed. Accounting for all site components, site carbon storage was significantly higher in dense and thinned plots compared with un-colonised plots due to elevated levels of soil and litter carbon as well as the presence of trees. The results indicate that thinning dense C. glaucophylla can maintain and (by some measures) improve site condition. However, given the variability in some of the parameters assessed, further study across a wider range of soil types and rainfall gradients is proposed. 相似文献
10.
细枝木麻黄离体培养过程中愈伤组织和再生芽的细胞组织学观察 总被引:1,自引:0,他引:1
为探讨细枝木麻黄(Casuarina cunninghamianaMiq.)愈伤组织分化过程的细胞组织学,对离体培养条件下的愈伤组织进行扫描电子显微镜和石蜡切片观察,分析愈伤组织的细胞分裂、分化以及芽再生的发生过程。结果表明,新鲜外植体培养于愈伤组织诱导培养基上,伤口处的薄壁细胞开始脱分化,培养1周后形成明显的愈伤组织;继续培养2周后,胚性愈伤组织形成,且表层细胞启动分化形成芽原基;培养4周,可肉眼观察到胚性芽原基,数量增多并逐渐分化形成不定芽;培养至第6周,生成不定芽,并大量增殖和分化。因此,细枝木麻黄是通过愈伤组织分化形成胚状体的途径进行植株再生的,为建立细枝木麻黄组织培养高效再生体系提供了理论依据。 相似文献
11.
A combined laboratory and field study examined the potential for a symbiotic association between the actinorhizal shrub Myrica cerifera and vesicular arbuscular mycorrhizal (VAM) fungi on a Virginia barrier island. M. cerifera seedlings and two test species, Zea mays and Strophostyles umbellata, were grown in an environmental chamber on soils collected from four sites differing in soil age (< 5 to over 130 years), salinity (1–35 g/g total soil chloride), and edaphic characteristics. Seedling root infection was significantly lower for all three species in the youngest soils from the beach where salinity was highest. Stained M. cerifera roots revealed all the components for a functional VAM association; however, there were significantly fewer arbuscules and vesicles relative to the test species. Among field-collected M. cerifera, infection was not detected in mature shrubs from the bay side of the island, where M. cerifera thickets were in a state of degeneration. Infection was highest in soils from the young, developing thickets, and in the most stable thickets of the island interior. Despite the dynamic nature of the barrier island environment, VAM associations with M. cerifera appear to be present, especially in seedlings and developing shrub thickets. 相似文献
12.
The mycotrophic character of Annona cherimola (Magnoliales), a tropical/subtropical plantation crop of interest, is described for the first time. This crop seems to depend on mycorrhizae (arbuscular) for optimal growth, with Glomus deserticola being the most effective endophyte tested. Study of the morphology of the arbuscular mycorrhizae in Annona roots showed exclusively intracellular hyphal development, with cell-to-cell fungal passage and an abundance of arbuscules and coiled hyphae within cells. Intercellular distributive hyphae were not observed. The morphology and the pattern of spread of the mycorrhizal colonization were similar for the different endophytes involved and appeared to be dependent on the host root. Such features of mycorrhizal colonization are characteristic of host species lacking intercellular air channels and have been described for some species of ecological interest, but they are not commonly noted in the mycorrhizal literature, especially that dealing with crop species. Some ecophysiological consequences of this pattern of colonization are discussed. 相似文献
13.
A factorial design 23 × 4 with two levels of Mussorie rockphosphate (RP) with or without vesicular-arbuscular mycorrhizal (VAM) fungi and Bradyrhizobium japonicum, and four treatments of phosphate-solubilizing microbes (PSM) Pseudomonas striata, Bacillus polymyxa, Aspergillus awamori was employed using Patharchatta sandy loam soil (Typic Hapludoll). The observations included mycorrhization, nodulation, grain and straw yield, N and P uptake, available soil P and the PSM population in the soil after crop harvest. Inoculation with endophytes alone caused about 70% root colonization. Addition of rockphosphate or inoculation with PSM, except B. polymyxa, stimulated root infection of native as well as introduced VAM endophytes. Application of RP or inoculation with Bradyrhizobium japonicum, mycorrhizal fungi or phosphate-solubilizing microorganisms significantly increased nodulation, N uptake, available soil P and the PSM population in the soil after the crop harvest. The grain and straw yields did not increase following RP addition or mycorrhizal inoculation but increased significantly after inoculation wit Bradyrhizobium or PSM. In general, the application of RP, Bradyrhizobium, VAM and PSM in combinations of any two or three resulted in significant increases in nodulation, plant growth, grain yield and uptake of N and P. Among the four factor interactions, rockphosphate, Bradyrhizobium and P. striata in the absence of VAM resulted in maximal nodulation, grain and straw yields and N uptake by soybean. The highest P uptake by soybean grain was recorded with Bradyrhizobium and A. awamori in the absence of rockphosphate and VAM. Generally, available soil P and PSM population after crop harvest were not significantly increased by the treatment combinations giving the maximal uptake of nutrients. However, they increased significantly in response to PSM, which produced no significant increase in total uptake of nutrients.Research paper no. 7498 相似文献
14.
该研究从广西钦州市采集健康的柳树桑寄生的根、茎和叶中分离并纯化内生真菌,对真菌进行形态学鉴定,提取内生真菌的DNA,采用真菌ITS序列对内生真菌进行分子鉴定。利用A549和H460细胞作为抗肿瘤活性指示细胞,采用MTT法测定真菌乙酸乙酯提取物的抗肿瘤活性。经过初步分离分析,从柳树桑寄生中纯化出27株内生真菌,经鉴定它们分别属于7个目9个属15个种。拟盘多毛孢属和间座壳属为优势属,其中拟盘多毛孢属全部定植于寄生根;其次为新壳梭孢属、拟茎点霉属和球座菌属,各分离到3株;其他包括青霉属、镰刀菌属、炭疽菌属和派伦霉属,各分离到1株。抗肿瘤活性研究表明,有一株与Pestalotiopsis protearum的ITS序列相似性达100%的拟盘多毛孢属菌株Gen24表现有抑制肿瘤细胞A549和H460生长的特性,在真菌乙酸乙酯浸提物浓度为800μg·mL~(-1)时,对A549细胞的抑制率达到了56.92%,对H460细胞的抑制率达到了70.11%。该研究结果表明广西柳树桑寄生内生真菌较丰富,在寄主中的分布表现了一定的组织特异性,而且还存在一些具有抗肿瘤活性的菌株及其活性物质可供进一步深入研究。 相似文献
15.
The effects of time after exposure to acetylene and of nodule excision were examined using a flow-through system. After a transient depression in the rate of acetylene reduction that began about 1.5 min after exposure to acetylene, the rate recovered to 98% of the initial maximum value after 40 min. After nodule excision the rate stabilized to 90% of the initial maximum value observed in the intact plant.Excised nodules, measured at 6-min intervals in a closed system, with frequent changes of the gas mixture, were used for the remaining experiments. Acetylene reduction by the nodules increased rapidly as temperature was increased between 6 and 26°C. Between 26 and 36°C there was relatively little effect of temperature on acetylene reduction.Nodules and cultures ofFrankia were compared with respect to the effect of temperature and pO2 (partial pressure of oxygen) on oxygen uptake. Cultures ofFrankia were grown on a nitrogen-free medium at either 0.3 kPa O2 (vesicles absent) or 20 kPa O2 (vesicles present). Oxygen uptake by nodules (vesicles absent) and by vesicle-containing cultures was strongly dependent on pO2 at values below 20 kPa. This suggests the presence of a barrier to oxygen diffusion. Oxygen uptake was dependent on temperature as well as on pO2, but the Q10 was much larger for the cultures than for the nodules. This suggests that vesicles or related structures are not the source of the diffusion barrier in Casuarina nodules. Respiration by cultures ofFrankia lacking vesicles became O2-saturated at low pO2 values. Thus these cultures did not have a significant diffusion barrier. From these results it is concluded that nodules ofCasuarina cunninghamiana have a barrier to oxygen diffusion supplied by the host tissue and not byFrankia. 相似文献
16.
The effect of phosphorus on nodule formation and function in the Casuarina-Frankia symbiosis 总被引:1,自引:0,他引:1
Yun Yang 《Plant and Soil》1995,176(1):161-169
A study was conducted to investigate the effects of phosphorus on nodule formation and function in the Casuarina-Frankia symbiosis. The effects of P on growth and survival of Frankia in the rhizosphere was assessed by examing Frankia growth and survival in flasks of basal nutrient solution. There was no growth in the nutrient solution during the experimental period. However, the viability of Frankia in the nutrient solution without P supply was half that of the initial level, whereas, with P supply, there was only a minor decline during the first week. In a growth pouch experiment, supplying P increased plant and nodule growth, irrespective of P status of the inoculant Frankia culture. There were no effects of P status on any growth or nodulation parameters measured when the inoculants had been standardized on the basis of viability. In a split root experiment, Frankia inoculation and application of P together or separately did not cause any significant difference. This suggests that growth and nodulation respond only to total P supply. Increasing P from 0.1 to 10 M significantly increased plant growth but not N concentrations. Both nitrogen-fixation and nitrate supported growth were strongly increased as P increased from 0.1 to 1.0 M. This study indicates that P deficiency limits the growth of host plants more severely than nitrogen fixation processes and P deficiency on nodulation and symbiotic nitrogen fixation in Casuarina cunninghamiana operated indirectly via reducing host plant growth. 相似文献
17.
Since its introduction into southern Florida at the beginning of this century, the Australian paperbark tree,Melaleuca quinquenervia (Cav.) S. T. Blake, has become a major economic and environmental pest. A project to develop biological control agents for this tree in Australia began in 1986. Among a number of potential agents, a defoliating sawfly,Lophyrotoma zonalis (Rohwer) (Hymenoptera: Pergidae), was selected for further study. The larvae of this sawfly are conspicuous defoliators ofMelaleuca trees in northern Queensland. We collected these sawflies from Cairns to Mackay in northern Queensland, and they are also known from the Northern Territory and New Guinea. The life-cycle from egg to adult takes about 12 weeks. The egg, larval and pupal stages are parasitized by dipteran and hymenopteran parasites. We conducted 2234 larval no-choice feeding tests on 46 plant species from 20 families. Although feeding occurred on 35 of these plant species,M. quinquenervia and its close relative,M. leucadendra (L.) L., were preferred. In oviposition tests, larvae only emerged from egg cases laid onM. quinquenervia andM. leucadendra. Our extensive field surveys of nearly 70 tree species foundL. zonalis eggs and larvae only on several closely relatedMelaleuca species. The potential effectiveness of this sawfly as a biocontrol agent is discussed and estimated using the Goeden-Harris scoring system. Quarantine studies of this insect began in Florida in early 1994. 相似文献
18.
Arbutoid mycorrhizae were synthesized in growth pouches between Arbutus menziesii Pursch. (Pacific madrone) and two broad host range basidiomycete fungi, Pisolithus tinctorius (Pers.) Coker and Couch and Piloderma bicolor (Peck) Jülich. P. tinctorius induced the formation of dense, pinnate mycorrhizal root clusters enveloped by a thick fungal mantle. P. bicolor mycorrhizae were usually unbranched, and had a thin or non-existent mantle. Both associations had the well-developed para-epidermal Hartig nets and intracellular penetration of host epidermal cells by hyphae typical of arbutoid interactions. A. menziesii roots developed a suberized exodermis which acted as a barrier to cortical cell penetration by the fungi. Ultrastructurally, the suberin appeared non-lamellar, but this may have been due to the imbedding resin. Histochemical analyses indicated that phenolic substances present in epidermal cells may be an important factor in mycorrhiza establishment. Analyses with X-ray energy dispersive spectroscopy showed that some of the granular inclusions present in fungal hyphae of the mantle and Hartig net were polyphosphate. Other inclusions were either protein or polysaccharides. 相似文献
19.
20.
Robert Mesibov 《ZooKeys》2015,(517):141-148
Cernethia
inopinata
gen. n., sp. n. is described from highland New South Wales. Like other dalodesmids the new species has numerous sphaerotrichomes on the legs of adult males, but Cernethia
inopinata sp. n. shares several character states with Tasmanian species in the genera Noteremus Mesibov, 2009, Paredrodesmus Mesibov, 2003 and Procophorella Mesibov, 2003, which lack sphaerotrichomes and have not yet been assigned to family within the suborder Dalodesmoidea. 相似文献