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1.
Modenutti  B.E.  Diéguez  M.C.  Segers  H. 《Hydrobiologia》1998,384(1-3):1-5
Hydrobiologia, with which I have had a long association, is celebrating its 50th anniversary in 1998. This year is also the 200th anniversary of Robert Malthus' still hotly debated publication on overpopulation. Readers of Hydrobiologia know well the impacts on the water resource of a growing human population, increased per capita affluence, major industrialization over much of the planet, and the explosion of new technologies that have effects on the water resource. Those concerned with the integrity and condition of water resources should be deeply involved in the debate on the exemption of human society from the biophysical laws of nature and its dependence on the life support services of ecosystems. Arguably, water resources will be the main battleground on which this debate is resolved. This discussion is a preliminary exploration of the primary issues. Even though the word water does not appear frequently in this paper, the connection to our profession and the future of the hydrobiological ecosystem and Hydrobiologia is present in every page.  相似文献   

2.
Two new lineid heteronemerteans, Kirsteueria abocellus gen. et sp nov. and Parborlasia hutchingsi sp. nov., from Sydney, New South Wales, are described and illustrated. The systematic relationships of these nemerteans are discussed and a key is provided to the known species of Parborlasia.  相似文献   

3.
Two new genera, Tasmanopteris and Heweria, from Tasmania are the first definite permineralized rhizomes assignable to the Matoniaceae. Tasmanopteris richmondii sp. nov., of mide-Mesozoic age, is from the Lune River site in southwestern Tasmania and is composed of four or more annular solenostelos separated by cortices with an inner mesarch xylem ring and outer exarch xylem rings. Secretory canals occur in the cortices between the protoxylem clusters of its outer xylem rings. The specimen of Heweria kempii sp. nov., which is very similar to extant Matonia, was collected from a Lower Tertiary conglomerate in central Tasmania but was reworked from older sediments. Anatomically, the rhizomes of Heweria consist of 3–6 annular solenosteles with the inner and middle xylem rings being mesarch, whereas the outer ring is exarch. Roots arise opposite the protoxylem clusters of the outermost ring. Epidermal hairs on the stems of this genus are like those of living Matonia in being attenuate, uniseriate, and multicellular.

Associated venation pattern of partially preserved leaves, isolated sporangia, annuli, and spores in this specimen provide additional support for the relationships of this fossil to modern Matonia.  相似文献   


4.
5.
Segers  Hendrik  Rong  Su 《Hydrobiologia》1998,379(1-3):175-181
The relationship of species abundance to eight environmental variables was tested for 24 common species of crustacean zooplankton collected in the Atchafalaya River Basin during the summer of 1994. Stepwise regressions (α = 0.05) revealed significant relationships between zooplankton abundance and at least one environmental variable for 18 species ( R2 = 0.14-0.61, p < 0.0435-0.0001). The majority of these species' peak abundances were correlated with variables indicative of seasonal changes in floodplain habitat, as the Atchafalaya river receded, water temperature increased, and/or phytoplanktonic photosynthesis increased. Surface water temperature and the percent saturation of dissolved oxygen showed the most significant relationships, but specific conductance, current velocity, and Secchi disk depths were also related to abundance patterns of certain taxa. A principal components analysis of species abundances provided further insight into the partitioning of temporally-distinct zooplanton assemblages, showing that several species ( Bosmina longirostris, Daphnia parvula, Eurytemora affinis, and Ceriodaphnia quadrangula) predominated during early summer, and were supplanted by a distinct late-summer assemblage ( Diaphanosoma birgei, Moina micrura, Mesocyclops edax, and Daphnia lumholtzi) as time progressed. The transitional assemblage was dominated by Simocephalus serrulatus, Macrocyclops albidus, Microcyclops rubellus, and Thermocyclops inversus, all of which were most abundant in the hypoxic conditions characteristic of the latter stages of the Atchafalaya River flood-pulse. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

6.
Two new species of the tropical Indo-Pacific gobiid genusSilhouetted, S. evanida andS. hoesei, are described from Darwin and Queensland, and the Cobourg Peninsula, N.T., respectively.S. evanida occurs in pools on intertidal sand flats along beaches and sandy creek mouths, andS. hoesei more sublittorally at 5–6 m on silty sand. A key to western Pacific and Australian species is included.  相似文献   

7.
A new species of Keratella is described from a small reservoir in Aguascalientes, Mexico. The species appears related to K. slacki Brziss, 1963 and K. lenzi Hauer, 1953.  相似文献   

8.
Internal parasites are reported from the goblin shark Mitsukurina owstoni for the first time. The shark examined was a 190 kg male collected off of Ulladulla, New South Wales, Australia and deposited at the Australian Museum in Sydney. What appear to be 4 different species of tapeworms were recovered from the spiral intestine. These included two new species, Litobothrium amsichensis n. sp. (order Litobothridea) and Marsupiobothrium gobelinus n. sp. (order Tetraphyllidea), as well as one specimen of a trypanorhynch and one scolex of a second tetraphyllidean. The latter two species are unidentifiable without further material. The generic placement of the new tetraphyllidean is somewhat problematical; this genus was thought to be the most appropriate placement at present. The most conspicuous difference between the new litobothridean and the five other species in the order is that it possesses dorso-ventral projections on five rather than four or three anterior segments. The discovery of a litobothridean parasitising the goblin shark is consistent with the systematic placement of the Mitsukurinidae within the Lamniformes, and may preliminarily indicate close affinities between the Alopidae, Odontaspidae and Mitsukurinidae. The phyllobothriid differs from the five other species of Marsupiobothrium in its possession of extremely long bothridial peduncles, its lack of an arcuate cylindrical pad on the posterior bothridial margins and its possession of a marginal, distinct apical sucker rather than a submarginal, diffuse apical sucker on each bothridium. Four detached specimens of the new phyllobothriid retained tips of mucosal villi within their bothridia. From these specimens it appears that the peduncles allow this species to stretch its scolex for attachment to up to four villi simultaneously.  相似文献   

9.
The novel species Agaricus lamelliperditus and A. colpeteii are described and illustrated, and affinities to other taxa determined by analysis of ITS sequence data. Both taxa resemble several other recently described Australian sequestrate Agaricus species, in particular A. pachydermus, A. wariatodes and A. chartaceus, which all have a powdery hymenophore from very early stages of basidiome formation. Both novel species have affinities to section Minores.  相似文献   

10.
11.
Seifert KA  Boulay H 《Mycologia》2004,96(4):929-934
Hirsutella uncinata, collected on follicles of Hakea sp. in New South Wales, Australia, is described as a new anamorph species. The fungus produces stiff, erect, verticillate conidiophores with up to 10 whorls of hooked, phialidic conidiogenous cells that have rough-walled necks. The conidia are subfusiform, flattened on one side and produced in groups of 2-3 in a dense slimy ball at the end of each phialide. Parsimony analysis of aligned internal transcribed spacer rDNA sequences suggests that H. uncinata is closely related to the Cordyceps sinensis complex (Clavicipitaceae, Hypocreales), which includes species with morphologically similar anamorphs.  相似文献   

12.
《Journal of bryology》2013,35(4):701-707
Abstract

A new species, Leptodontiumparadoxum, is described from southern Australia. It differs from L. viticulosoides, a widespread species which occurs in southern Queensland, in the entire leaf margin and in the smaller and less conspicuous patch of inner basal cells.  相似文献   

13.
Two new bythitid genera and species of the subfamily Brosmophycinae are described from Northern Territory, Australia.Brosmolus longicaudus, described from a single male specimen, is unique in the tribe Brosmophycini in having the anal fin origin well anterior to the midpoint of the body and thin, transparent skin on the head and body.Beaglichthys macrophthalmus, described from a single female specimen, differs from all other genera in the subfamily by the following combination of characters: eight branchiostegal rays, eye diameter longer than snout length, cheek scaly, anal fin origin at midpoint of body, three developed rakers on the first gill arch, 12 caudal fin rays, and 14 precaudal vertebrae.  相似文献   

14.
《Journal of bryology》2013,35(3):359-364
Abstract

Fissidens traversii, a new species from Queenslahd, Australia, is characterised by the rounded leaf apex, costa papillose and finishing short of the apex, mamillose, multipapillose cells, short dorsal lamina and vaginant laminae (which usually have a marginal strip of transversely elongated calls in the lower half), reaching almost to the apex of the leaf.  相似文献   

15.
《Journal of bryology》2013,35(3):181-189
Abstract

A new species, Racomitrium patagonicum Bednarek-Ochyra &; Ochyra, is described from southern South America. A herbarium name, R. senile Schimp. in A. Jaeger, is considered synonymous with R. patagonicum and confusion associated with its interpretation is explained. The new species belongs to the type subgenus of Racomitrium and is closely alied to R. lanuginosum (Hedw.) Brid. from which it differs by the very long and broadly decurrent, ruffled or wavy margins of the hyaline hair-point, broadly canaliculate leaves and dull green, strongly papillose laminal cells. Grimmia glacialis Müll. Hal., hom. illeg. (=Racomitrium glaciale Kindb.) from South Georgia is typified and this name is considered synonymous with Racomitrium lanuginosum subsp. lanuginosum. Distribution of the new species is mapped. A key to species of Racomitrium subg. Racomitrium is provided.  相似文献   

16.
An account is given of an undescribed bat-flea found in a jar with an alcohol-preserved specimen of the Australian giant false vampire bat and a new genus is erected for its inclusion.  相似文献   

17.
Bulbophyllum panigrahianum sp. nov. and Liparis vestita Reichb. f. ssp. seidenfadenii ssp. nov. are described here as new to science.  相似文献   

18.
Two new species of Siriella, S.australiensis sp. nov. and S.spinulasp. nov., are described here. Siriella australiensis is distinguishedby the character of the third and fourth pleopods of the male.Siriella spinula is characterized by the short frontal spineof the labrum and the short linguiform telson showing sexualdimorphism.  相似文献   

19.
20.
Two new species of the sciaenid genusNibea are described;N. squamosa from northern Australia and Papua New Guinea andN. microgenys from northern Australia. Both species differ from all known congeners in having a small, inferior mouth, with the lower jaw teeth uniform in size.N. squamosa is distinguished fromN. microgenys by a higher number of lateral line scales (57–60 vs. 48–50), the last pleural rib on the 11th vertebra (vs. 10th), and a longer and more slender caudal peduncle (length 25.9–30.4%SL, depth 6.3–7.9% SL vs. 21.5–26.3, 8.0–10.3).N. squamosa exhibits hyperostosis in some elements, such as the frontals and dorsal and anal pterygiophores.  相似文献   

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