Stygobromus quatsinensis, a new amphipod crustacean (Crangonyctidae) from caves on Vancouver Island, British Columbia, with remarks on zoogeographic relationships

1987 ◽  
Vol 65 (9) ◽  
pp. 2202-2209 ◽  
Author(s):  
John R. Holsinger ◽  
D. Patrick Shaw

Stygobromus quatsinensis, a new species of subterranean, freshwater amphipod crustacean, is described from caves on Vancouver Island, British Columbia, Canada. This is the 3rd stygobiont amphipod recorded from Canada and the 11th member of the genus Stygobromus to be found in localities north of the southern limits of Pleistocene glaciation. Stygobromus quatsinensis is a member of the hubbsi group, an assemblage of closely similar stygobiont species previously recorded from the central and western United States south of British Columbia. Two alternative hypotheses are proposed to explain the presence of S. quatsinensis on a glaciated island separated from the mainland by marine straits. One theory suggests that it evolved from putative ancestors that were present on the island before development of the Juan de Fuca Strait in the Eocene. The other suggests that it gained access to the island from the mainland through interstitial routes in coarse sediments of the Quadra Sand which infilled parts of the Georgia Strait in the late Pleistocene. Both theories assume that this species has survived glaciation in subglacial groundwater refugia.

1979 ◽  
Vol 16 (9) ◽  
pp. 1645-1657 ◽  
Author(s):  
Neville F. Alley ◽  
Steven C. Chatwin

The major Pleistocene deposits and landforms on southwestern Vancouver Island are the result of the Late Wisconsin (Fraser) Glaciation. Cordilleran glaciers formed in the Vancouver Island Mountains and in the Coast Mountains had advanced down Strait of Georgia to southeastern Vancouver Island after 19 000 years BP. The ice split into the Puget and Juan de Fuca lobes, the latter damming small lakes along the southwestern coastal slope of the island. During the maximum of the glaciation (Vashon Stade), southern Vancouver Island lay completely under the cover of an ice-sheet which flowed in a south-southwesterly direction across Juan de Fuca Strait, eventually terminating on the edge of the continental shelf. Deglaciation was by downwasting during which ice thinned into major valleys and the strait. Most upland areas were free of ice down to an elevation of 400 m by before 13 000 years BP. A possible glacier standstill and (or) resurgence occurred along Juan de Fuca Strait and in some interior upland valleys before deglaciation was complete. Glacial lakes occupied major valleys during later stages of deglaciation.


1993 ◽  
Vol 71 (2) ◽  
pp. 401-406 ◽  
Author(s):  
A. Brinckmann-Voss ◽  
D. M. Lickey ◽  
C. E. Mills

A new species of colonial athecate hydroid, Rhysia fletcheri, is described from Vancouver Island, British Columbia, Canada, and from Friday Harbor, Washington, U.S.A. Its relationship to Rhysia autumnalis Brinckmann from the Mediterranean and Rhysia halecii (Hickson and Gravely) from the Antarctic and Japan is discussed. Rhysia fletcheri differs from Rhysia autumnalis and Rhysia halecii in the gastrozooid having distinctive cnidocyst clusters on its hypostome and few, thick tentacles. Most of its female gonozooids have no tentacles. Colonies of R. fletcheri are without dactylozooids. The majority of R. fletcheri colonies are found growing on large barnacles or among the hydrorhiza of large thecate hydrozoans. Rhysia fletcheri occurs in relatively sheltered waters of the San Juan Islands and on the exposed rocky coast of southern Vancouver Island.


1979 ◽  
Vol 36 (10) ◽  
pp. 1223-1227
Author(s):  
D. D. Lemon ◽  
P. H. LeBlond ◽  
T. R. Osborn

Seiche motions observed in San Juan Harbour with a bottom-mounted pressure gauge have been Fourier-analyzed and interpreted in terms of a theoretical model of oscillations in a rectangular basin with an exponential depth profile. Two of the observed periods (at 14.6 and 38.5 min) are identified with resonances of the basin; two other significant low frequency peaks (at 21 and 55 min) do not coincide with resonant periods of the basin and must be due to strong external forcing. Higher frequency fluctuations (20–160 s) are attributed to swell and to its subharmonic interactions with edge waves. Key words: water waves, seiches, mathematical model, Juan de Fuca Strait, British Columbia


1982 ◽  
Vol 39 (5) ◽  
pp. 736-747 ◽  
Author(s):  
Richard J. Beamish

Lampetra macrostoma n.sp., a freshwater parasitic lamprey, is distinguished from related species L. tridentata, L. lethophaga, L. folletti, L. minima, and L. similis by its parasitic habit and very large disc. Other characters distinguishing the species from L. tridentata are its longer prebranchial length, large eye, weakly pigmented velar tentacles, and its ability to remain in freshwater. The recently metamorphosed form readily survives in freshwater and probably is non-anadromous even though it can survive in salt water. The new species has been discovered in two lakes on Vancouver Island, British Columbia, Canada, where it attacks large numbers of resident salmonids. Because of its ability to survive and feed in freshwater, it poses a definite threat to freshwater fishes.Key words: lamprey, new species, non-anadromous lamprey, salmonid parasitism


1964 ◽  
Vol 21 (5) ◽  
pp. 933-939 ◽  
Author(s):  
Richard H. Rosenblatt

A new species, Pholis clemensi, referred to the family Pholidae, is named and described from 12 specimens taken in southern British Columbia waters and the Strait of Juan de Fuca. Pholis clemensi is compared with other members of the genus, and a key is given to the North American species.


Author(s):  
Alessandro Garassino ◽  
Torrey Nyborg ◽  
John Fam ◽  
Dan Bowden ◽  
Raymond Graham ◽  
...  

A new porcellanid crab, Petrolisthes landsendi Garassino & Nyborg n. sp., from the Upper Cretaceous (upper Santonian) Nanaimo Group of Vancouver Island (British Columbia, Canada) is herein described. Petrolisthes landsendi Garassino & Nyborg n. sp. represents the oldest species of Petrolisthes Stimpson, 1858 and is the first species from the northeastern Pacific, thus expanding the stratigraphical age and geographical range of the genus.


1971 ◽  
Vol 8 (7) ◽  
pp. 788-801 ◽  
Author(s):  
M. J. Berry ◽  
W. R. Jacoby ◽  
E. R. Niblett ◽  
R. A. Stacey

Geophysical studies of the crust and upper mantle have been conducted in the Canadian Cordillera for over two decades, but only recently have sufficient data been collected to permit a synthesis and a correlation with the major geological units. The studies have included gravity, heat flow, and magnetotelluric observations, geomagnetic depth sounding, and high level aeromagnetics as well as both small and large scale refraction and reflection seismic surveys.It now appears that major crustal units may be recognized geophysically:(i) Seismic and gravity data suggest that the Plains and Rocky Mountains are underlain by two units of the North American craton with a crustal section 45–50 km thick. The northern unit appears to terminate at the Rocky Mountain Trench while the southern unit may extend to the Omineca Geanticline.(ii) The combined geological and geophysical data suggest that the Rocky Mountain Trench and possibly the Kootenay Arc near the 49th parallel mark the edge of the Precambrian continental margin and that the western Cordillera was formed by a complex succession of plate interactions with repeated reactivation of block boundaries.(iii) A combination of magnetic and heat flow data suggest that the region between the Rocky Mountain Trench and the Fraser Lineament is part of the Cordilleran Thermal Anomaly Zone recognized by Blackwell in the United States.(iv) Seismic data in Central British Columbia suggest that the Pinchi Fault system is a boundary between two crustal blocks.(v) The crustal thickness of the Coast Geanticline appears to increase gradually to the west to approximately 40 km and, at least in southern British Columbia, does not have a root zone below the mountains.(vi) The crustal section beneath Vancouver Island is abnormally thick and there is some paleomagnetic data which suggest that the Island may not have been formed in its present position, contiguous to the Cordillera. The crustal section for the northern part of the Insular Trough is significantly thinner.(vii) The active spreading of the Juan de Fuca Rise – Explorer Trench is now well documented. The geophysical data suggest active subduction of the Juan de Fuca plate beneath Oregon, Washing-ton, and southern Vancouver Island. However, further north there is no evidence for subduction.


1966 ◽  
Vol 23 (6) ◽  
pp. 805-811 ◽  
Author(s):  
Tai Soo Park

A new species Bradyidius saanichi from Saanich Inlet, Vancouver Island, British Columbia, Canada, is described and illustrated in detail. This species is closely related to B. pacificus (Brodsky, 1950) among the six previously known species in the genus, but can be readily distinguished from the latter by the strongly divergent rostral rami in addition to some other differences.


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