Mouth-brush dimorphism in larvae of Opifex fuscus Hutton (Diptera, Culicidae)

1963 ◽  
Vol 54 (2) ◽  
pp. 325-327 ◽  
Author(s):  
D. D. McGregor
Keyword(s):  
Particle Size ◽  
New Zealand ◽  
Blood Serum ◽  
Room Temperature ◽  
East Coast ◽  
Food Particle ◽  
Fish Food ◽  
First Instar ◽  
Hair Type

Among larval populations of the mosquito Opifex fuscus Hutton from supralittoral pools on the east coast of South Island, New Zealand, some individuals in the second, third and fourth instars had only simple hairs in their mouth-brushes, others had pectinate bristles. All first-instar larvae had simple hairs, and samples of these from the same pool were reared in the laboratory at 25°C. Of 13 fed on dehydrated blood serum, only two developed pectinate bristles, but of 15 fed on fish food (particle size 0·1–0·6 mm.), all but one did. Of a later sample of 16 reared at room temperature on fish food in the first two instars and then on the blood serum, all developed pectinate bristles in the second instar but had reverted to simple hairs by the fourth. In nature, larvae of O. fuscus observed to be feeding by filtering were predominantly of the simple-hair type and those browsing of the pectinate-bristle type. Environmentally controlled dimorphism may increase the probability that an individual will develop to maturity.

Effects of food particle size on Perca fluviatilis larval growth

1998 ◽  
Vol 60 (2) ◽  
pp. 89-98 ◽  
Author(s):  
Lakhdar Tamazouzt ◽  
Claude Leray ◽  
Anne-Marie Escaffre ◽  
Denis Terver
Keyword(s):  
Particle Size ◽  
Larval Growth ◽  
Perca Fluviatilis ◽  
Food Particle

Tectonic and paleoclimatic significance of Quaternary river terraces of the Waipaoa river, east coast, North Island, New Zealand

2000 ◽  
Vol 43 (2) ◽  
pp. 229-245 ◽  
Author(s):  
Kelvin Berryman ◽  
Michael Marden ◽  
Dennis Eden ◽  
Colin Mazengarb ◽  
Yoko Ota ◽  
...  
Keyword(s):  
New Zealand ◽  
East Coast ◽  
River Terraces ◽  
Paleoclimatic Significance

The Recent Cypraeidae of Northern New Zealand from the Kermadec Islands to the Poor Knights Islands, Southwest Pacific Ocean (Mollusca: Gastropoda: Cypraeidae)

The Festivus ◽  
2018 ◽  
Vol 50 (1) ◽  
pp. 36-54
Author(s):  
John Daughenbaugh
Keyword(s):  
New Zealand ◽  
Pacific Ocean ◽  
Continental Shelf ◽  
East Coast ◽  
Species Distributions ◽  
East Side ◽  
Tropical Eastern Pacific ◽  
The North ◽  
The Poor ◽  
Coastal Shelf

For researchers, isolated regions at the periphery of species’ distributions hold a peculiar fascination. The causes of their remoteness vary based on: distance (e.g. the Tropical Eastern Pacific), distance and countervailing currents (e.g. the Marquesas), location in a present day gyre (e.g. the Pitcairn Group) or the absence of present day means of veliger transport (e.g. the Vema Seamount). (Daughenbaugh & Beals 2013; Daughenbaugh 2015a & b, 2017). The northern New Zealand Region from the Kermadec Islands (Kermadecs) to the coastal and shelf areas in the northernmost part of New Zealand’s North Island (Northland), including the Poor Knights Islands (PKI), constitute the distributional boundaries for a number of Cypraeidae species. The boundaries are the result of the absence of coastal shelves along the east side of the Kermadec Ridge (Ridge) and precipitous drops to abyssal depths along Northland’s east coast continental shelf. Tropical waters, with their potential to transport Cypraeidae larvae, flow eastward from southern Queensland, Australia, entrained in the Tasman Front which terminates when reaching North Cape, the northernmost tip of Northland. There, the North Cape Eddy captures most of this flow while the remainder, the East Auckland Current (EAUC), flows intermittently southward along the eastern coastal, shelf and offshore areas of Northland into waters incapable of supporting Cypraeidae populations.

LUCERNE IN THE WELLINGTON, TARANAKI, AND EAST COAST DISTRICTS

1936 ◽  
pp. 92-95
Author(s):  
A.G. Elliott ◽  
T.W. Lonsdale
Keyword(s):  
New Zealand ◽  
West Coast ◽  
East Coast ◽  
General Trend ◽  
Present Position ◽  
Department Of Agriculture ◽  
Forage Crop ◽  
High Rainfall ◽  
The North ◽  
Subsequent Discussion

IN two papers read by officers of the Department of Agriculture at the 1936 conference of the New Zealand Grassland Association, the growing of lucernc as a forage crop in districts of relatively high rainfall was dealt with. The area covered by the papers included the Manawatu and west coast from Paraparaumu to the Patea River(I) and Taranaki(n). During the subsequent discussion on these and other papers the present position and general trend in regard to lucernegrowing in the Wairarapa, Eiawke's Eay, and Poverty Bay districts were also touched on. It is the intention here. to review briefly some of the more important points in regard to the cultivation of lucerne in the southern portion of the North Island as discussed at the conference.

Ingesta particle size, food handling and ingestion in the tammar wallaby (Macropus eugenii Desmarest)

1999 ◽  
Vol 47 (1) ◽  
pp. 75 ◽  
Author(s):  
R. G. Lentle ◽  
K. J. Stafford ◽  
M. A. Potter ◽  
B. P. Springett ◽  
S. Haslett
Keyword(s):  
Particle Size ◽  
New Zealand ◽  
Particle Size Distribution ◽  
Stomach Contents ◽  
Tammar Wallaby ◽  
Food Handling ◽  
Macropus Eugenii ◽  
Food Particles ◽  
Chewing Rates ◽  
Free Ranging

The particle size distribution of stomach contents from 25 tammar wallabies (Macropus eugenii Desmarest) shot in the Okataina State Forest and adjoining farmland near Rotorua, New Zealand, were determined. There was a greater percentage of finer, and a smaller percentage of larger, particles than reported in the stomach contents of larger macropods. The chewing and biting activities of four free-ranging tammars fitted with radio-microphone collars were monitored. Chewing rates (chews per minute) were similar to those of other small herbivorous vertebrates. There were significantly lower rates of chewing and higher chew-to- bite ratios when browsing than when grazing. Observations of browsing by three captive tammars showed inefficient handling by mutually opposed palms and digitopalmar grip, resulting in low rates of ingestion. We suggest that tammars lower the time necessary for fermentation of food by reducing the size of food particles, and that their choice between graze and browse is influenced by food handling and chewing investment.

Geodetic strain and the deformational history of the North Island of New Zealand during the late Cainozoic

1987 ◽  
Vol 321 (1557) ◽  
pp. 163-181 ◽  
Keyword(s):  
New Zealand ◽  
Subduction Zone ◽  
East Coast ◽  
Late Quaternary ◽  
Plate Boundary ◽  
Boundary Zone ◽  
Metamorphic Belt ◽  
Volcanic Region ◽  
The North ◽  
Plate Boundary Zone

The subduction zone under the east coast of the North Island of New Zealand comprises, from east to west, a frontal wedge, a fore-arc basin, uplifted basement forming the arc and the Central Volcanic Region. Reconstructions of the plate boundary zone for the Cainozoic from seafloor spreading data require the fore-arc basin to have rotated through 60° in the last 20 Ma which is confirmed by palaeomagnetic declination studies. Estimates of shear strain from geodetic data show that the fore-arc basin is rotating today and that it is under extension in the direction normal to the trend of the plate boundary zone. The extension is apparently achieved by normal faulting. Estimates of the amount of sediments accreted to the subduction zone exceed the volume of the frontal wedge: underplating by the excess sediments is suggested to be the cause of late Quaternary uplift of the fore-arc basin. Low-temperature—high-pressure metamorphism may therefore be occurring at depth on the east coast and high-temperature—low-pressure metamorphism is probable in the Central Volcanic Region. The North Island of New Zealand is therefore a likely setting for a paired metamorphic belt in the making.

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