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1.
Common bivalve larvae from New Zealand: Leptonacea   总被引:1,自引:1,他引:0  
The late stage larvae of three erycinid bivalves (Mollusca: Pelecypoda: Leptonacea) taken from the brood chamber of the adult are described (Kellia cycladiformis, Lasaea rubra hinemoa, and L. maoria), and the provisionally identified late stage larva of the erycinid Arthritica bijurca taken from the plankton is described. Also, the D‐shaped larvae of the erycinid bivalves Kellia cycladiformis, Borniola reniformis, Arlhritica crassijormis, and A. bifurca taken from the parent brood chamber are described. The seasonal occurrence of each late stage larva in the plankton at the Bay of Islands (35° 15'S, 174° 10'E), Wellington Harbour (41° 16'S, 174° 51'E), and Raumati Beach (40° 56'S, 174° 58'E), New Zealand is described. Aspects of the reproductive cycles of Lasaea rubra hinemoa and Arthritica bifurca are presented.  相似文献   

2.
Twelve common bivalve larvae occurring in the plankton from the Bay of Islands (35°15'S, 174°10'E), Wellington Harbour (41°16'S, 174°51'E), and off Raumati Beach (40°56'S, 174°58'E), New Zealand, during 1970–72 are described and, wherever possible, provisionally identified. The seasonal occurrences of these larvae in the plankton are also described. Information on the spawning cycles of some New Zealand adult bivalves is reviewed; although some species have a short (4 months or less) spawning season, for most it is much longer, possibly with ‘trickle’ spawning through several months of the year.  相似文献   

3.
Meiobenthos from the Waiwhetu Stream (41°14.22′S, 174°54.28′E), a heavily polluted site, was low in density and numbers of species; a tubificid oligochaete Limnodrihts cf. hoffmeisteri dominated. In the Hutt River estuary (41°14.09′S, 174°53.85′E), meiofauna density was the same as in similar sediments world‐wide, but dominance by 2 species of harpacticoid copepods produced a low‐diversity assemblage. The fauna in the Pauatahanui Inlet (41°05.2′S, 174°54.05′E) was comparable in density and diversity to the faunas of muddy estuarine sediments in other parts of the world. The dominance of nematodes, abundance of Echinoderes cf. coulli (Kinorhyncha), and the variety of species suggest that the Pauatahanui site was the most normal of the 3 sampled.  相似文献   

4.
Rough water as a spawning stimulus in some Trochid and Turbinid gastropods   总被引:1,自引:1,他引:0  
Adults of three species of common intertidal gastropods, Melagraphia aethiops, Zediloma atrovirens, and Lunella smaragda, were collected from Waitemata Harbour, Auckland (36° 51 S, 174° 47 E) and brought to the laboratory, where several methods of artificial spawning were attempted throughout the year. The one successful method, involving vigorous water movement around ripe adults, induced them to release gametes during their respective spawning seasons, and was equally effective in the natural habitat. Larval stages were found in the plankton only during periods of on‐shore wind speeds greater than 10 knots, with which their presence was correlated, rather than with tides, lunar cycles, or sea temperatures.  相似文献   

5.
Samples of simple ascidians of the genera Asterocarpa, Cnemidocarpa, Corella, and Pyura were collected from Wellington Harbour, New Zealand (41°16'S, 174° 51'E) and three species of the crustacean family Notodelphyidae were recovered, all from the branchial baskets of the ascidians.

Pygodelphys novaeseelandiae (Schellenberg), and two new species of Doropygus, are described and illustrated.  相似文献   

6.
The flora and fauna of Pupu Springs (40°51'S, 172° 46'E) and five other New Zealand cold springs are described. In Pupu Springs there are 16 species of algae, 10 species of bryophytes (including three species of liverworts), and 5 species of angiosperms. The fauna includes a phreatic form (an eyeless planarian, Dugesia sp.), a possible glacial relict (the caddis fly Rakiura vernale), and cold stenotherms (e.g., the caddis fly Psilochorema tautoru). The most abundant animals in the New Zealand springs are Mollusea, Crustacea, and’ larvae of Plecoptera, Diptera, and Trichoptera.

Pupu Springs consist of five biotopes and associated biocoenoses.  相似文献   

7.
Axiothella serrata n. sp. (Polychaeta: Maldanidae) is described and illustrated from intertidal sands of Porirua Harbour, New Zealand (41° 6′ S, 174° 52′ E). It has 22 setigerous segments, and lacks asetigerous preanal segments; the mid‐ventral anal cirrus is conspicuously lengthened. The species is compared with other Axiothella species. A. catalinia Hartman, 1969 is herein transferred to Maldanella.  相似文献   

8.
Eight species of Pycnogonida collected by University of Canterbury Expeditions and the New Zealand Oceanographic Institute are recorded from the Snares Islands, which lie at 48° 05’ S, 166° 20’ E, 60 miles SW of South Cape, Stewart Island. The following species are recorded: Pallenopsis obliqua (Thomson, 1884), Cheilopallene trappa n.sp., Ammothea magniceps Thomson, 1884, Achelia dohrni (Thomson, 1884), Tanystylum cavidorsum Stock, 1957, Ascorhynchus insularum n.sp., Austrodecus minutum n.sp. and Austrodecus enzoi n.sp.  相似文献   

9.
The seasonal cycles of abundance of the phytoplankton and zooplankton in Lake Ototoa, Northland, at 36° 31 S, 174° 14 E, are described. Concentrations of chlorophyll a were low (range 0.04–4.61 mg.m‐3; mean 0.97 mg.m‐3), and highest values were in winter. Phytoplankton densities were also low; an oligo‐trophic diatom‐desmid assemblage associated with Botryococcus, Dinobryon, and Svhaerocyslis was found.

The zooplankton was dominated by the calanoid copepod Calamoecia lucasi whose numbers remained fairly constant throughout the year, and the only other copepod found was the cyclopoid Mesocyclops leuckarti which was present in very low numbers. Bosmina meridionalis was the only limnetic cladoceran and was most abundant during autumn and spring. A number of rotifer species were also common.  相似文献   

10.
We report the occurrence and distribution of Carapidae larvae in the southwest Atlantic Ocean, between Real River (12°S) and São Tomé Cape (22°S), off Brazil. Carapidae larvae were collected during three oceanographic cruises: spring 1998, winter 1999 and autumn 2000. The hauls were conducted obliquely from a maximum depth of 200 m, during day and night, with bongo nets 330- and 500-μm mesh size. Three species were recorded in this study: Carapus bermudensis, Echiodon dawsoni and Snyderidia canina. Only one C. bermudensis was collected during the winter cruise off the Salvador coast (13°S). Twenty-one larvae of E. dawsoni were collected during the three cruises between 14.5° and 22°S, including some at the banks of Vitória–Trindade Ridge. One S. canina larva occurred, during the spring in the north coast of Rio de Janeiro (22°S).  相似文献   

11.
The beaks of four species of Lycoteuthidae (Cephalopoda: Oegopsida) were found in stomachs of black petrels Procellaria parkinsoni Gray (Aves: Procellariiformes) breeding on Little Barrier Island (36° 12'S, 175° 05'E). Two of these squids, Lycoteuthis diadema (Chun, 1900) and Oregoniateuthis longimanus (Steenstrup, 1857), previously have not been reported specifically from the south‐west Pacific Ocean. The others, which are much smaller, have not been positively identified. Lycoteuthis diadema seems to be common within the feeding range of this petrel, but to be restricted to northwards of 38° S in this region. Oregoniateuthis lorigera (Steenstrup, 1875), the binomen under which this taxon has been known hitherto, is shown to be a junior synonym of O. longimanus.  相似文献   

12.
本研究于2015年在黑龙江省镜泊湖选取7个典型采样点,对镜泊湖春、夏两季间浮游生物群落结构的演替及其与环境因子关系进行分析。在调查期间共鉴定浮游植物152个分类单位,浮游动物38个分类单位,种类组成上浮游植物主要以绿藻门和硅藻门藻类为主,浮游动物以轮虫和原生动物为主。研究期间浮游生物优势种主要包括:河生集星藻(Actinastrumfluviatile(Schroed.)Fott)、梅尼小环藻(Cyclotella meneghiniana Kütz.)、谷皮菱形藻(Nitzschia palea (Kütz.) W.Smith)、前节晶囊轮虫(Asplanchna priodonta)、螺形龟甲轮虫(Keratella cochlearis)和瓶砂壳虫(Difflugia urceolata)。在研究期间水温、pH、电导率、和总氮在春、夏两季之间变化明显(P0.05或P0.01)。春、夏两季的浮游生物丰度呈现明显下降趋势(P0.05)。Spearman相关分析揭示镜泊湖水体浮游生物丰度与水温和电导率极其显著相关(P0.01)。冗余分析(RDA)表明,水温和电导率是驱动镜泊湖水体浮游生物群落生态分布的主要环境因子。与近10余年间镜泊湖相关研究对比发现,镜泊湖水体浮游植物群落结构较为稳定,浮游动物优势类群略有改变。综合营养状态指数评价表明镜泊湖水体为中营养状态,与前期研究结果相似,说明水体目前无进一步恶化的趋势。  相似文献   

13.
Phyllosomata and nistos of Scyllarus sp. Z taken from plankton around and offshore northern New Zealand and in the Tasman Sea are presumed to be those of S. aoteanus Powell, 1949, the most common Scyllarus species in this area. The full larval and postlarval development of this species are described. Three features are characteristic of Scyllarus sp. Z phyllosomata; a dorsal crest on the cephalic shield, dorsal thoracic spines, and a forked telson in middle stages persisting as two prominent spines outreaching the telson posterior margin in the final stage. Scyllarus sp. Z's closest affinities are with a group of Scyllarus species whose phyllosomata have forked telsons in middle stages and medium to strong posterolateral telson spines in the final stage. The nisto is low in profile but distinctive in its armature. Too few Scyllarus sp. nistos have been described to suggest any group to which that of Scyllarus sp. Z can be assigned. The spatial and temporal distribution of the larvae and postlarvae of Scyllarus sp. Z are also described. Although early larval stages and postlarvae are found close to New Zealand, mid‐ and late‐stage larvae are widely distributed, some well beyond the known latitudinal range of the adults. There is probably an extended egg‐bearing and hatching period as early stage larvae are caught in most months. Variable rates of development of the larvae and/or delayed metamorphosis, are also possible.  相似文献   

14.
The distributions of two swimming crabs endemic to the New Zealand region are described, mostly from material obtained at 118 of 2544 New Zealand Oceanographic Institute benthic stations sampled.

Nectocarcinus antarcticus (Jacquinot) was found within the geographic limits 34°S‐51°S and 166° E‐176° W, with concentrations around Cook Strait, the Chatham Rise, Foveaux Strait, and the Auckland Is. N. bennetti (Takeda & Miyake) occurred between 44° S and 53° S, and 165° E and 180°, most frequently in the south and west, on the ‘highs’ of the Campbell Plateau. Although the distributions overlap between 44° S and 51° S, and this overlap zone produced most of the available material, only one joint occurrence of the two species was noted. This apparent separation was not satisfactorily explained by any of the ecological factors recorded. The depth ranges of both species were broadly similar (0–550 m for TV. antarcticus, 20–474 m for JV. bennetti); both were most frequently obtained at depths less than 200 m. Both occurred primarily on the coarser sediment grades, though N. antarcticus occupied a broader range of grades than N. bennetti.

The size ranges of the two species were similar; carapace lengths were 8.0–62.0 mm for N. antarcticus and 5.8–68.0 mm for N. bennetti. The larger specimens of both species were found towards the southern limits of distribution. Larger specimens of N. antarcticus were absent from depths greater than 120 m; smaller N. antarcticus and all N. bennetti occurred throughout their respective depth ranges. Ovigerous N. antarcticus (smallest, 8.8 mm carapace length) were obtained at depths of 17–263 m from May to October; ovigerous N. bennetti (smallest 36.1 mm) were from depths of 150–183 m in May only.  相似文献   

15.
A colonial ascidian was first reported by marine farmers in Houhora Harbour, Northland, New Zealand in early 2005 and subsequently found on oyster racks in Parengarenga Harbour and the Bay of Islands. The Northland ascidian was identified with a combination of morphological characters and DNA cytochrome c oxidase I (COI) sequence data, as Eudistoma elongatum, a species native to Australia, where it is found from northern New South Wales to Northern Queensland, and distinguished from Eudistoma circumvallatum, the only reported species in this genus from New Zealand. Ascidian larvae are weak dispersers and long distance dispersal of E. elongatum is likely to be enhanced by vectors such as oyster barges and/or movement of cultured oysters. In its native range, E. elongatum is restricted to areas with a minimum winter sea temperature of 16°C. Assuming similar biological limitations apply in New Zealand, the spread of E. elongatum might be restricted to northern New Zealand (north of latitude 37°S).  相似文献   

16.
On 4 January 1971 a solitary specimen of the broadbilled swordfish Xiphias gladius Linneaus (Osteichthyes: Xiphiidae) was shot in Croisilles Harbour (41° 04’ S, 173° 40’ E). This was the first time the species has been recorded in the Tasman Bay area.  相似文献   

17.
Seasonal and tidal variations in the hydrology of Wellington harbour   总被引:1,自引:1,他引:0  
Observations were made on several hydrological features of Wellington Harbour, New Zealand (41° 16’ S, 174° 51’ E) during 1970 to 1972. These suggest that the harbour is topographically partially isolated from oceanic influences, and that waters within the harbour undergo efficient mixing.

Monthly mean sea‐surface temperatures ranged seasonally between 10.5°c and 18.5°c, and some stratification was observed during summer and winter. Salinities usually ranged from 33.5‰ to 34.5‰, and water transparency by Secchi disc from 3 m to 6 m. Dissolved oxygen content ranged from 96% to 127% saturation, usually exceeding 100% saturation in surface waters.

Under normal discharge conditions during winter, the Hutt River was observed to markedly affect surface temperatures and salinities as far south as Somes Island to a depth of about 5 m.  相似文献   

18.
Pycnogonida collected at the Antipodes Islands (49° 45’ S, 178° 45’ E) by the University of Canterbury Antipodes Islands Expedition 1969 and during New Zealand Oceanographic Institute cruises are reported on here, and constitute all material known for this group of animals from these islands. To date eight species are known; two are endemic, (Pallenopsis antipoda n.sp. and Ammothea antipodensis n.sp.); two constitute a circum‐polar element (Tanystylum cayi‐dorsum Stock and Austrodecus breviceps Gordon); the remaining four species are known also from New Zealand mainland waters (Pallenopsis obliqua (Thomson), P. kupei n.sp., Achelia dohrni (Thomson) and Ammothea magniceps Thomson), as is T. cavidorsum. An attempt is made to indicate the range of variation in Achelia dohrni, and Pallenopsis mauii Clark, 1958 is redescribed although not a part of the Antipodes Islands fauna.  相似文献   

19.
The reproductive biology and population dynamics of the cirolanid isopod Excirolana armata (Dana, 1853) were analysed through monthly samples from December 2003 to November 2005 on Una beach, São Paulo state (24° S), in Southeastern Brazil. Sampling was performed along three transects established from the base of foredunes to the waterline. On Una beach, E. armata showed continuous reproduction with higher abundances of ovigerous females in winter and spring (July–November) with a higher peak of juveniles in spring (November 2004). The fecundity ranged from 2 to 18 eggs/embryos per female, depending on the female length. The incubation period was estimated as 2 months. The life span of males and females was nearly 1 year. The short life span and the high energetic expenditure inherent to reproduction with maternal care, probably kept females from producing more than one brood in their lifetime. When comparing the population of E. armata on Una beach (24° S) with populations in Southern Brazil (32° S), Uruguay (34° S) and Argentina (36° S), it was verified that several biological population traits (length of the smallest juvenile, length of the largest individual, length of the smallest and largest ovigerous females, range of fecundity and life span) tended to increase at higher latitudes, whereas other traits (instantaneous rate of mortality and the curvature parameter of von Bertalanffy growth function) tended to decrease. However, comparing E. armata on Una beach (24° S) with a population situated at a close latitude (25° S), unexpected differences in relation to population structure and to growth demonstrated and reinforced the importance of density‐dependent factors over life history traits of E. armata on dissipative beaches.  相似文献   

20.
In January 1970, 309 pups of the New Zealand fur seal, Arctocephalus forsteri (Lesson, 1828), were tagged on Taumaka Island, one of the Open Bay Islands, Westland, New Zealand (43°52’ S, 168°53’ E). At about 6 weeks old, male pups have longer flippers and are longer and heavier than female pups.

A population estimate of seals on Taumaka Island is based on a count of pups of the year, to which data from related species of fur seals were applied (incidence of pregnancy and age at first pupping from Arctocephalus pusillus, immature mortality from Callorhinus ursinus), and on the assumptions that the sex ratio and sexual mortalities are equal. There were at that time 2,000–3,000 seals, including pups, on the island.  相似文献   

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