首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
The New Zealand distributions of three species of Boeckella (Copepoda, Calanoida), B. triarticulata, B. dilatata and B. hamata are mapped. B. triarticulata is primarily a pond dweller but is also found in reservoirs and shallow lakes. B. dilatata is mainly found in the deeper glacial lakes and ponds in the central region of the South Island and B. hamata has a more widespread distribution in lakes and ponds in the South Island and lower half of the North Island. Differences in temperature optima, food requirements and dispersal ability among the three Boeckella species are related to vicariant events to explain their distribution in New Zealand.  相似文献   

2.
Several medusa species have been described from inland waters in Australia, Eurasia, Africa and America. The chief objective of this study is to summarize all species described from freshwater and from saline lakes, because the knowledge about this group is sparse and scattered in the literature. I summarize all accessible literature to deduct how many species of freshwater medusae exist and to show their distribution, relation and their phylogenetic origin.All medusae described from freshwater except Halmomises are Olindiidae (Limnomedusae). More than 20 Olindiidae species (in 6 genera) have been recorded from freshwater. However, about half of them may not be valid species or have been described insufficiently or improperly. Within the genera Craspedacusta only 3 (or 5) species are certain (C. sowerbii, C. iseanum, C. sinensis (and maybe C. sichuanensis and C. ziguiensis)). The genera Limnocnida may consist of 6 species, three from Africa (L. tanganjicae, L. victoriae, L. congoensis) and 3 from India (L. indica, L. biharensis, L. nepalensis). The status of Astrohydra (from Japan), Mansariella and Keralika (both from India) is uncertain. Additionally, the present study suggests that Craspedacusta and at least one type of Calpasoma hydrants are identical and Astrohydra may be closely related to Craspedacusta and/or Calpasoma.A comparison of the freshwater medusae with species described from saline lakes and brackish sites (Australomedusae from Australia and Moerisia from Egypt, Black Sea, Caspian Sea and Ganges Estuary) shows that these two groups are not closely related.  相似文献   

3.
This study examines the molecular‐genetic divergence and evolution of Australian aquatic micro‐Crustacea Daphnia and Daphniopsis. The results indicate that species of Daphniopsis are accommodated within the genus Daphnia. Although their phyletic integrity is no longer supported, all Daphniopsis species (save one from North America) form a monophyletic group and may warrant subgeneric recognition pending further systematic investigations. A total of five lineages are shown to occupy Australian inland waters, including an endemic subgenus (Australodaphnia) and representatives of the subgenus Ctenodaphnia. The subgenera (Daphnia and Hyalodaphnia) that dominate the North American fauna are absent in Australia. The large extent of sequence divergence among major groups suggests that continental isolation has helped shape the early evolution of daphniids. More recent speciation is also evident, particularly by the Daphnia carinata species complex, whose numbers have grown to 13 members by the addition of a species previously assigned to the nominal subgenus and species yet to be formally described. The molecular data provide more evidence that the colonization of distinct habitats and ecological settings is a key factor in spurring diversification in the genus, while also modulating the pace of molecular evolution. This study attributes habitat‐specific molecular clocks to the intense ultraviolet (UV) exposure in both saline and transparent oligohaline waters. Adaptations to these harsh environments by at least four independent lineages include the convergent acquisition of a melanic carapace. Yet some lineages, clearly under mutational duress, lack this commonly acquired protective trait. There are numerous adaptive lines of defense against UV damage, including the complex regulatory mechanisms required to initiate a cellular response to guard and repair DNA. Functional molecular studies may soon challenge a notion built on morphology that convergence is the general directive to Daphnia’s ecological and evolutionary success. © 2006 The Linnean Society of London, Biological Journal of the Linnean Society, 2006, 89 , 469–488.  相似文献   

4.
The aim of the project was to determine the effects of sudden change in potassium concentration in inland saline water on the survival, osmolality and condition indices of western Australian King Prawn—Penaeus latisulcatus Kishinouye. Australia has large volumes of inland saline water that could be used for aquaculture but is often deficient in K+. Western king prawn is a candidate species for culture in inland saline water. Such waters require K+ fortification for prawn survival and growth. Trials were conducted in tanks to determine the effect of sudden change in K+ concentration in inland saline water samples on the survival, osmolality and condition indices of western king prawns. Prawns in tanks were acclimated to inland saline water procured from Wannamal—an inland location in Western Australia. After 3 days of acclimation, prawns were subjected to sudden increase in medium K+ concentration over 1 h, ranging from 80% to 100% of the marine water K+ concentration by adding potassium chloride. Identical inland saline water was added to the control tanks over the same time period. Survival, ingestion rate and osmoregulatory capacity (OC) were then recorded over 19 days. At the conclusion of the trial, survival ranged from 71% to 78% in the potassium-enriched tanks whereas 100% mortality was observed in the control tanks by day 11. Ingestion rate of prawns was significantly higher in the experimental tanks than in the control. Osmoregulatory capacity of potassium-enriched prawns was significantly lower post- than pre-ionic change and significantly higher at the conclusion of the trial than both pre- and post-ionic change. There was no significant difference in OC between water types at any time period. These results indicate that prawns can tolerate sudden increase in K+ content in inland saline water and the higher K+ concentration increases survival and OC, but other measures indicate the prawns were experiencing stressful conditions. Guest Editors: J. John & B. Timms Salt Lake Research: Biodiversity and Conservation—Selected Papers from the 9th Conference of the International Society for Salt Lake Research  相似文献   

5.
The attraction of male pollinating insects by sexual deception is known for several orchids from the Mediterranean, Australia, South Africa and South America. The sexual delusion may be so enticing in some species that it elicits males to attempt copulation with insect-like structures of the labellum. Pollination by such a pseudocopulation mechanism is reported here for the terrestrial orchid Geoblasta penicillata (Chloraeinae) from subtropical South America. Observations of the pollination process were carried out in two wild populations 560 km distant from each other. The only pollinators seen in both populations were male Campsomeris bistrimacula (Scoliidae) wasps. They attempted copulation with the insect-like labellum by directing the genitalia to its base whereby pollinia got attached to the dorsal surface of the metasoma. The present case of pseudocopulation, which is in South America the second known and the first recorded in wild populations, represents a striking parallel to the Australian Calochilus campestris also pollinated by male scoliid wasp of the genus Campsomeris.  相似文献   

6.
Saline lakes of the Paroo,inland New South Wales,Australia   总被引:11,自引:11,他引:0  
B. V. Timms 《Hydrobiologia》1993,267(1-3):269-289
Twenty-five lakes from fresh to crystallizing brine in the semi-desert of northwestern New South Wales, Australia, were studied regularly for 27 months. The lakes are small, shallow and ephemeral. Chemically waters are mainly of the NaCl type. Seventy-four species of invertebrate occur in saline waters (>3 g l–1) with crustaceans such as Parartemia minuta, Apocyclops dengizicus, Daphniopsis queenslandensis, Diacypris spp. and Reticypris spp. dominant, particularly at higher salinities. The insects Tanytarsus barbitarsis and Berosus munitipennis are also important in meso- and hypersaline lakes. They are joined in hypo- and mesosaline waters by many others, including more beetles, odonatans, trichopterans, pyralids, notonectids, and corixids. Species richness declines with increasing salinity. There is a prominent inland faunal component mainly of crustaceans, including P. minuta, D. queenslandensis, R. walbu, Trigonocypris globulosa and Moina baylyi.  相似文献   

7.
Senecella calanoides Juday has been reported from fresh-water lakes of North America, Northern Siberia and inshore brackish waters of Kara and Laptev Seas. Investigation of 11 females and 2 males from the brackish waters of Neelov Bay (Laptev Sea) shows that second species, Senecella siberica sp. n., can be distinguished from S. Calanoides Juday by the greater size, a slightly asymmetrical female genital segment, the 3 external spines on the 3d exopod of 2 to 4th swimming legs and by more longer left endopod digitiform process of the male 5th legs. S. siberica seems to be brackish-water euryhaline species, inhabiting brackish waters with salinity from 1 to 22. The genus belongs to the family Aetideidae and is the only genus with freshwater representatives.  相似文献   

8.
After examining numerous water samples of 19 lakes and reservoirs in Venezuela, only two species of Daphnia were found: D. laevis (in colder, high altitude lakes) and D. gessneri. This observation supports the theory of the scarcity of Daphnia species in tropical inland waters.  相似文献   

9.
Edward J. Maly 《Oecologia》1984,62(2):173-181
Two calanoid copepod genera, Boeckella and Calamoecia have broadly similar geographic distributions in Australia but Boeckella is more common than Calamoecia. A field survey and literature search indicate that Boeckella is usually the first calanoid to colonize newly formed bodies of water, and Boeckella is more common in temporary pools and in high altitude environments. Boeckella usually produces larger clutches than Calamoecia, increasing its probability of establishment in lakes and ponds; calculations indicate that Boeckella's probability of establishment is far greater than that of Calamoecia. That Calamoecia is common on the North Island of New Zealand may be due to the presence of planktivorous fish; small species are more likely to survive in such environments. Calamoecia clutches may be able to move more often and farther than those of Boeckella but Calamoecia remains rare because its probability of establishment is low. Boeckella may be able to survive temporary pool environments not only because it can produce larger clutches, but also because many species in this genus are highly pigmented, and as such can survive brightly lighted environments. Patterns of abundance of North American diaptomids appear to be consistent with factors affecting those of Australian and New Zealand centropagids.  相似文献   

10.
Golovinomyces is a strictly herb-parasitic genus in the Erysiphaceae. Host–parasite co-speciation was reported recently between the genus Golovinomyces and Asteraceae from molecular phylogenetic analyses. The Asteraceae originated in South America and latterly expanded their geographic distribution into the Northern Hemisphere. If the co-speciation between Golovinomyces and Asteraceae originated in South America, the geographic origin of Golovinomyces could be assumed to be South America. To address this question, Golovinomyces species from hosts of the tribe Mutisieae, an asteraceous tribe endemic to South America, were collected and the ITS and 28S rDNA regions sequenced. Results indicate that Oidium mutisiae and Golovinomyces leuceriae isolated from the Mutisieae do not belong at the base of the Golovinomyces tree. Instead, they are situated separately within two different clades of Golovinomyces isolates from the Northern Hemisphere. Therefore, the tribe Mutisieae is not the most early host of Golovinomyces. Present results suggest that Golovinomyces originated in the Northern Hemisphere, and not in South America. The new species Oidium reginae for the previous O. mutisiae on Mutisia decurrens is proposed.  相似文献   

11.
Menu-Marque  S. A.  Zúñiga  L. R. 《Hydrobiologia》1994,292(1):81-87
A new species of Boeckella from limnetic samples of Laguna del Diamante, a high lake in the Andes (34°10 S) is described and illustrated. The species is defined by the characters of the male fifth leg: the right two segmented endopod bears four peculiar, short, claw-like spines, the left endopod is a simple finger-like projection. This species is related to B. gibbosa, also a species from the Andes and B. vallentini from Malvinas (Falkland Islands) and other subantarctic islands. It is distinguished from them by diagnostic features of the fifth legs of the male and abdominal structure and fifth legs of the female. Some current views on the features used in the taxonomy of the genus Boeckella are discussed.  相似文献   

12.
Trophi of Filinia species from 16 South Island lakes and three North Island lakes of New Zealand were examined and compared with specimens from Australia, Austria, Belgium, and Turkey. Five species of Filinia (brachiata, longiseta, cf. pejleri, novaezealandiae, and terminalis) were positively identified from the New Zealand samples. Numbers of unci teeth are considered to be the most reliable features for identification within the genus. Numbers obtained from SEM for other species of Filinia (australiensis, grandis, and hofmanni) are also listed for the first time.  相似文献   

13.
A number of species in the plant pathogen genus Armillaria are known from South America where they cause root rot disease on a wide variety of hosts. Knowledge pertaining to phylogenetic relationships of these species with those of other Armillaria species is almost non-existent. In addition, very few cultures representing these species are available, making DNA-based phylogenetic analyses impossible. The aim of this study was to characterise a collection of Armillaria isolates from the Patagonian Andes using DNA sequences and to determine their phylogenetic relationships with other Armillaria species. DNA sequences were obtained from the internal transcribed regions (ITS1, 5.8S and ITS4) and ribosomal large subunit (LSU) gene and used in phylogenetic analyses. Phylogenetic trees generated from the sequences separated the Armillaria isolates into four lineages. Lineages I and II represented A. novae-zelandiae and A. luteobubalina, respectively. Isolates belonging to A. novae-zelandiae from Malaysia, New Zealand, Australia and South America showed considerable intra-clade sub-structure. Lineages III and IV are probably distinct species and are most closely related to A. hinnulea and an unnamed species isolated from New Zealand and Kenya. This is the first comprehensive study of the phylogenetic relationships of Armillaria species from Patagonia and it provides a foundation for future research in this region.  相似文献   

14.
Two geometrid moths Chiasmia inconspicua and Chiasmia assimilis, identified as potential biological control agents for prickly acacia Acacia nilotica subsp. indica, were collected in Kenya and imported into quarantine facilities in Australia where laboratory cultures were established. Aspects of the biologies of both insects were studied and CLIMEX® models indicating the climatically favourable areas of Australia were developed. Host range tests were conducted using an approved test list of 74 plant species and no-choice tests of neonate larvae placed on both cut foliage and potted plants. C. inconspicua developed through to adult on prickly acacia and, in small numbers, Acacia pulchella. C. assimilis developed through to adult on prickly acacia and also in very small numbers on A. pulchella, A. deanei, A. decurrens, and A. mearnsii. In all experiments, the response on prickly acacia could be clearly differentiated from the responses on the non-target species. Both insects were approved for release in Australia. Over a three-year period releases were made at multiple sites in north Queensland, almost all in inland areas. There was no evidence of either insect’s establishment and both colonies were terminated. A new colony of C. assimilis was subsequently established from insects collected in South Africa and releases of C. assimilis from this new colony were made into coastal and inland infestations of prickly acacia. Establishment was rapid at one coastal site and the insect quickly spread to other infestations. Establishment at one inland area was also confirmed in early 2006. The establishment in coastal areas supported a CLIMEX model that indicated that the climate of coastal areas was more suitable than inland areas.  相似文献   

15.
A new species of the genus Daphniopsis found in Australian salt lakes is described and illustrated. A differential diagnosis and short taxonomic remarks are presented.  相似文献   

16.
How many species of Cladocera are there?   总被引:4,自引:4,他引:0  
An estimation of the number of taxa within families, genera and local faunas of Cladocera reveals that only c. 129 species (17% of all known species) may be considered as sufficiently well described (valid species), and c. 146 as rather well described (fair species) but needing further study using modern methods of investigation. The status of all other species is vague. The families Chydoridae, Daphniidae and Sididae and genera Diaphanosoma, Daphnia, (including Daphniopsis), Megafenestra, Scapholeberis, Eurycercus, Chydorus, Ephemeroporus and Pleuroxus have been comparatively studied best. The largest number of valid species is known from Europe, North America, Australia and South America, and the smallest number from Africa. Presence of large number of vague species of Cladocera negatively affects faunistic, zoogeographic, and ecological studies of continental waters.Dedicated to the memory of Professor D. J. Frey  相似文献   

17.
【背景】白花鬼针草为农区恶性杂草,原产于美洲,现已广泛分布于世界热带及亚热带地区,但其在全球和中国的适生区域及适生等级还不明确。【方法】利用MaxEnt生态位模型对白花鬼针草在全球以及中国的潜在适生区进行预测。【结果】白花鬼针草在全球的分布更多受到温度因素的影响。白花鬼针草的适生区主要集中在北半球和南半球15°~30°之间的热带和亚热带地区。其中,北美南部、南美中南部、非洲南部、东南亚北部以及大洋洲中南部沿海地区为白花鬼针草中、高度适生区。白花鬼针草在中国的适生区主要位于广东、广西、海南、云南、福建、台湾。到2070年,白花鬼针草在全球的适生区面积与当前相似,但在中国的适生区有所增大。【结论】白花鬼针草在我国有进一步扩张的风险。  相似文献   

18.
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   

19.
Three new species of Myrtaceae (Calyptranthes bracteata, Eugenia gonglycocarpa, andMyrcia rupta) from northeastern South America are described and illustrated, and a new combination (Eugenia tetramera) is proposed. The closed-calyx and the completely or partially fused cotyledons ofMyrcia rupta, unusual features for the genus, are discussed and compared with related species inMyrcia andMarlierea.  相似文献   

20.
Eva Pip 《Hydrobiologia》1987,153(3):203-216
The distribution of 17 Potamogeton species was examined at 430 sites in central North America with respect to water body type, bottom substrate and 8 water chemistry parameters (pH, total dissolved solids, total alkalinity, chloride, sulphate, phosphorus, combined nitrate and nitrite, and dissolved organic matter). All except 2 of the species showed statistically significant distributions with respect to some of the environmental parameters examined. Each species occupied a different combination of chemical parameter ranges. The species formed a distribution spectrum with respect to water chemistry, with P. epihydrus and P. obtusifolius frequenting low inorganic concentrations at one end of the scale, and P. filiformis, P. pectinatus and P. vaginatus at the other end, these species characterized by high mean inorganic values and occurring most often in saline or alkaline habitats. While 41 significant positive interspecific associations were found within the genus in lentic waters, only 4 were apparent in lotic habitats. Potamogeton species richness (PR) was related to water body and bottom type, with lakes and sand bottoms showing the highest mean PR values. Stepwise multiple regression analysis showed that, in the area as a whole, the water chemistry parameters examined accounted for <25% of the observed variability in PR. The relative importance of individual chemical parameters in relation to PR varied in different water body types.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号