The agnostoid arthropod Lotagnostus Whitehouse, 1936 (late Cambrian; Furongian) from Avalonian Cape Breton Island (Nova Scotia, Canada) and its significance for international correlation

AbstractNew and archival collections from the Chelsey Drive Group of the Avalon terrane of Cape Breton Island, Nova Scotia, Canada, yield late Cambrian trilobites and agnostoid arthropods with full convexity that contrast with compacted, often deformed material from shale and slate typical of Avalonian Britain. Four species of the agnostoid Lotagnostus form a stratigraphic succession in the upper Furongian (Ctenopyge tumida–Parabolina lobata zones). Two species, L. ponepunctus (Matthew, 1901) and L. germanus (Matthew, 1901) are previously named; L. salteri and L. matthewi are new. Lotagnostus trisectus (Salter, 1864), the type species of the genus, is restricted to compacted material from its type area in Malvern, England. Lotagnostus americanus (Billings, 1860) has been proposed as a globally appropriate index for the base of ‘Stage 10’ of the Cambrian. All four species from Avalonian Canada are differentiated clearly from L. americanus in its type area in Laurentian North America (i.e., from debris flow blocks in Taconian Quebec). In our view, putative occurrences of L. americanus from other Cambrian continents record very different species. Lotagnostus americanus cannot be recognized worldwide, and other taxa should be sought to define the base of Stage 10, such as the conodont Eoconodontus notchhpeakensis.

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PREVALENCE OF SPHAERULARIA BOMBI (NEMATODA: TYLENCHIDA: SPHAERULARIIDAE) IN BUMBLE BEE QUEENS (HYMENOPTERA: APIDAE) ON CAPE BRETON ISLAND, NOVA SCOTIA, CANADA

The Canadian Entomologist ◽

10.4039/ent130877-6 ◽

1998 ◽

Vol 130 (6) ◽

pp. 877-882 ◽

Cited By ~ 9

Author(s):

D.B. McCorquodale ◽

R.G. Beresford ◽

J.M. Francis ◽

C.E. Thomson ◽

C.M. Bartlett

Keyword(s):

Nova Scotia ◽

North America ◽

First Record ◽

Nematode Parasite ◽

Bumble Bee ◽

Cape Breton Island ◽

Cape Breton ◽

Dramatic Variation ◽

Nest Parasite ◽

Nesting Season

AbstractSphaerularia bombi Dufour is an internal nematode parasite of bumble bee queens in North America and Europe. Infection functionally castrates the bee. Here we document the prevalence and intensity of S. bombi infections in seven species of Bombus and three species of Psithyrus on Cape Breton Island, Nova Scotia, Canada. We found dramatic variation in prevalences among Bombus spp., and some evidence that prevalence increased as the nesting season progressed. Also, we report S. bombi in the bumble bee nest parasite Psithyrus insularis (Smith), the first record for the genus in North America.

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The Ainslie Detachment: a regional flat-lying extensional fault in the Carboniferous evaporitic Maritimes Basin of Nova Scotia, Canada

Canadian Journal of Earth Sciences ◽

10.1139/e96-016 ◽

1996 ◽

Vol 33 (2) ◽

pp. 169-181 ◽

Cited By ~ 14

Author(s):

Gregory Lynch ◽

Peter S. Giles

Keyword(s):

Nova Scotia ◽

Hanging Wall ◽

Cape Breton Island ◽

Fine Grained ◽

Cape Breton ◽

Westerly Direction ◽

Maritimes Basin ◽

Highly Strained ◽

Planar Fabric ◽

Stratigraphic Succession

The Ainslie Detachment occurs near the base of the Carboniferous Windsor Group, forming a regional flat-lying extensional fault distributed across 10 000 km2. New mapping has delineated the structure through southwestern Cape Breton Island and into central Nova Scotia. Shearing is concentrated at the top of the basal Macumber limestone along its contact with overlying evaporites and younger allochthonous units. The highly contrasting rheologies of the formations created an anisotropic zone of weakness which acted as an upper crustal stress guide, stratigraphically controlling the trajectory of the detachment through the basin. The detachment is characterized by an approximately 3–10 m thick calc-mylonite zone, with an intense planar fabric featuring alternating very fine grained shear planes and coarser annealed layers. Coarser layers are boudinaged into pinch and swell structures, locally producing segmented augen. Highly strained intraclasts, ooids, and peloids, recrystallized carbonate boudins, and carbonate vein segments are included in the calc-mylonite as semirigid inclusions and rotated porphyroclasts. Thick zones of fault breccia straddle portions of the detachment and overprint the mylonite, demonstrating an evolution to brittle conditions during progressive shear. Listric faults in the hanging wall of the detachment feature a ramp and flat geometry, with an upper detachment occurring along the upper contact of the Windsor Group with the overlying Namurian Mabou Group. Locally up to 2 km of the stratigraphic succession has been removed, with faults cutting downsection in a westerly direction producing rollover in the hanging wall.

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The First Record for Altai Fescue, Festuca altaica (Poaceae), in Nova Scotia, from an Eastern Alpine Site on Cape Breton Island

The Canadian Field-Naturalist ◽

10.22621/cfn.v131i2.1861 ◽

2017 ◽

Vol 131 (2) ◽

pp. 164-169

Author(s):

Stephen Darbyshire ◽

Sean Blaney ◽

Sean Basquill

Keyword(s):

Nova Scotia ◽

North America ◽

First Record ◽

Grass Species ◽

Southern Limit ◽

Cape Breton Island ◽

Northeastern North America ◽

Alpine Habitat ◽

Cape Breton

Altai Fescue, Festuca altaica Trinius, is an amphi-Beringian grass species also known from isolated, but widespread, locations in northeastern North America. The occurrence reported here, at the southern limit of eastern alpine habitat in Canada, represents the first for Nova Scotia.

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DESCRIPTIONS OF NEW SPECIES REPRESENTING NEW OR UNREPORTED GENERA OF LEBERTIOIDEA (ACARI: HYDRACHNIDA) FROM NORTH AMERICA

The Canadian Entomologist ◽

10.4039/ent123811-4 ◽

1991 ◽

Vol 123 (4) ◽

pp. 811-825 ◽

Cited By ~ 8

Author(s):

Ian M. Smith

Keyword(s):

New Species ◽

Nova Scotia ◽

North America ◽

Northern California ◽

Coast Range ◽

Cape Breton Island ◽

Cape Breton ◽

Adult Females ◽

Three New Species

AbstractAdult females of Rutripalpus canadensis sp.nov. (family Rutripalpidae) from Cape Breton Island, Nova Scotia, Canada, adults of both sexes of Scutolebertia trinitensis gen.nov., sp.nov. (family Lebertiidae) from the Coast Range in northern California, USA, and adults of both sexes of Pseudotorrenticola chiricahua sp.nov. (family Torrenticolidae) from Arizona, USA, are described. The three new species represent the first members of their respective genera to be reported from North America, and their discovery provides new perspectives on the phylogeny and biogeography of mites in these genera.

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Taxonomic revision of the long-tailed shrew, Sorex dispar Batchelder, 1911, from the Appalachian Region of North America, with the description of a new subspecies

Journal of Mammalogy ◽

10.1093/jmammal/gyz127 ◽

2019 ◽

Vol 100 (6) ◽

pp. 1837-1846 ◽

Cited By ~ 1

Author(s):

Victor E Diersing

Keyword(s):

Nova Scotia ◽

North America ◽

New Brunswick ◽

Geographic Variation ◽

Skull Morphology ◽

Connecticut River ◽

Cape Breton Island ◽

New Subspecies ◽

Morphological Studies ◽

Cape Breton

Abstract The long-tailed shrew, Sorex dispar Batchelder, 1911, and Gaspe shrew, S. gaspensis Anthony and Goodwin, 1924, from the Appalachian Mountains of North America have been characterized as genetically highly similar, and that one is morphologically a clinal variate of the other, i.e., there is a single species. I measured 24 characters of the skull on 196 shrews from throughout the range of the species. Geographic variation in skull shape and size was not gradual or continuous, but abrupt. These abrupt changes in morphology are associated with major water barriers, primarily the Connecticut River, middle Saint John River, and the Strait of Canso, which separates mainland Nova Scotia from Cape Breton Island. The morphological analyses presented here and previous genetic studies indicate that S. dispar and S. gaspensis are likely conspecific. Shrews with the largest skull occur from North Carolina north to Vermont and are referable to S. d. dispar with S. d. blitchi as a synonym. Shrews from New Hampshire northeast to southern New Brunswick and mainland Nova Scotia have a medium-sized skull and are referable to a new subspecies. Those from northern New Brunswick, Gaspe Peninsula of Quebec, and Cape Breton Island have a small skull and are referable to S. d. gaspensis. The skull morphology of S. d. gaspensis and the new subspecies are more similar to each other than to S. d. dispar. Results of this study differ from those of previous morphological studies because measurement error and within-group variation were reduced, which allowed for visibility of otherwise “hidden” between-group differences, or geographic variation.

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