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This paper examines the status and geographic distribution of the genera Hypenetes Loew and Tillobroma Hull; the status of the latter was shifted to generic level by Artigas & Papavero 1991. The genus Clavator Philippi, which is preoccupied, becomes synonymous to Tillobroma Hull, this has been proposed by Artigas & Papavero (1991), and is confirmed here. Hypenetes and Tillobroma have a possible common Gondwanan origin of approximately 180 millions years ago. Even though the external characters barely allow separation between the two genera, the obvious differences in spermathecae structures permit the inference of other internal differences and reinforce the independent status of the genera. This conclusion is also supported by 180 million years of interrupted genetic drift and the 8,500 km distance between the populations. A key to separate the species of Tillobrama is provided. Of a total of 21 species, ten are new for science: aconcaguana, angulata, fucosoides, huasquina, leucoptera, leucotrica, nahuelbutae, purpurea, spinipes and tregualemuensis. The species belonging to this genus are distributed in Argentina, Bolivia, Brazil, Paraguay, Peru and especially Chile (where 19 of 21 are found). A phylogenetic study for the species in the genus was performed. Two South African species, Hypenetes grisescens Engel and Hypenetes stigmatias Loew, were used as external group. The software used was NONA 2.0 (heuristic search). The tree of strict consensus separated the out group by nine synapomorphies from the species H. stigmatias with four autopomorphies Se estudia el estatus y la distribución geográfica de los géneros Hypenetes Loew y Tillobroma Hull, este último elevado al rango de género por Artigas & Papavero (1991). El género Clavator Philippi está preocupado y es sinónimo de Tillobroma Hull, lo que fue propuesto por Artigas y Papavero 1991 y confirmado en el presente trabajo. Se concluye que Hypenetes y Tillobroma tienen un posible origen gondwánico común desde aproximadamente 180 millones de años. Aunque los caracteres externos difícilmente permiten separar las especies de ambos géneros, las notables diferencias en las espermatecas, que permiten inferir otras diferencias internas, aseguran el estatus independiente de ambos géneros, avalado además por 180 millones de años de interrupción del flujo genético y de 8.500 km de distancia entre ambas poblaciones. El estudio filogenético del género Tillobroma, usando dos especies sudafricanas como grupo externo: Hypenetes grisescens Engel e Hypenetes stigmatias Loew, muestra nueve sinapomorfías que sustentan la monofilia de Tillobroma. Se incluye una clave para separar las especies de Tillobroma. De las 21 especies tratadas, diez son nuevas para la ciencia: aconcaguana, angulata, fucosoides, huasquina, leucoptera, leucotrica, nahuelbutae, purpurea, spinipes y tregualemuensis. Las especies del género están distribuidas en: Argentina, Bolivia, Brasil, Paraguay, Perú y, principalmente Chile (19 de 21)

The first record of the defoliating activity of Antandrus viridis (Blanchard) (Orthoptera: Acrididae) and Coniungoptera nothofagi Rentz y Gurney (Orthoptera: Tettigoniidae) on adult stands of Pinus radiata D. Don in Chile, is reported. Some aspects of their biology are also presented., Se reporta, por primera vez, la presencia de Antandrus viridis (Blanchard) (Orthoptera: Acrididae) y Coniungoptera nothofagi Rentz y Gurney (Orthoptera: Tettigoniidae) defoliando plantaciones adultas de Pinus radiata D. Don en un área precordillerana de la VIII Región de Chile. Además, se entregan algunos antecedentes acerca de su biología.

The Queen Charlotte Islands, located within the Insular Belt off the central British Columbia coast, preserve a lithologically diverse group of volcanic, sedimentary, and intrusive rocks ranging in age from Late Paleozoic to Late Tertiary. This study analyzes the deformation history recorded in these rocks through regional and detailed structural analyses of five map areas comprising 20% of the islands' landmass. The structural model constrained by these studies involves at least four distinct deformation events. Earliest formed structures are Middle Jurassic northwest-trending, southwest-verging folds and contractional faults which accommodated approximately 50% regional structural shortening. During the late Middle Jurassic to Early Cretaceous, dip-slip motion along steep faults tectonically elevated northwest-trending fault blocks, exposing uplifted areas to preferential erosion of Middle Jurassic and older strata. In the Late Cretaceous to Early Tertiary, a second episode of northeast-southwest shortening added an additional 10% regional shortening, concentrated in high-strain zones in Cretaceous strata overlying re-activated block faults. Tertiary structural styles were dominated by strike-slip and extensional faulting, coinciding with the onset of syn-tectonic sedimentation in the adjacent Queen Charlotte Basin. Structural styles associated with these events reflect the variable mechanical properties of the deforming units. During periods of crustal shortening, most regional strain was accommodated by movement along steeply-dipping reverse faults in homogeneous, poorly-layered rocks, while well-bedded rocks shortened by mesoscopic to macroscopic folding and movement along shallowly-dipping thrust faults. Strike-slip and extensional faulting episodes were characterized by displacements along steeply-dipping fault surfaces in all units. Penetrative structural fabrics preserved in Mesozoic rocks include axial planar slaty cleavage, mylonitic foliation, and wall-rock foliations adjacent to major fault surfaces, and all can be tied to some aspect of the documented structural history. Spaced cleavage fabrics in Cretaceous mudstones are interpreted to have formed as dilatent fractures during sediment dewatering and lithification. Throughout deformation, strains were accommodated by semi-brittle processes of crystalline plasticity (dislocation glide and dislocation creep, twin gliding), pressure solution creep, and brittle failure (extensional and shear fracturing, microcracking, andcataclastic flow). Regional metamorphic conditions were sub-greenschist grade, except for locallized areas affected by pluton heating. This structural history includes substantial refinements of existing models for the structural evolution of the Queen Charlotte Islands, the most significant of which include: 1. ) the characterization of Mesozoic contractional and extensional deformation events, and the recognition of their significance to the present stratigraphic distribution and structural configuration, 2. ) the delineation of a concentrated strain zone in the central Queen Charlotte Islands, and the recognition that its formation was linked to Mesozoic contraction and extensional events, rather than Tertiary strike-slip faulting as previously interpreted, 3. ) the evolution of a general structural model for the Queen Charlotte Islands region in Tertiary time integrating structural, magmatic, sedimentological, and geophysical constraints.

The boundary between the Omineca Belt and the Intermontane Belt in Central British Columbia represents the suture between autochthonous North America (Barkerville Terrane) and several allochthonous terranes accreted from the west In the Quesnel Lake region allochthonous sedimentary and volcanic rocks of Quesnellia Terrane, accreted in the Jurassic, are in sharp tectonic contact with underlying siliclastic and carbonate metasedimentary rocks. The Ogden Peak study area is located 10 km east of and structurally below this suture zone and is thus well situated for observing deformational styles within the autochthonous package. Rocks exposed near Ogden Peak comprise the Hadrynian(?) to Paleozoic(?) Snowshoe Group and local diabasic intrusions. These rocks record a deformational history involving four phases of folding (D₁-D₄) and later brittle faulting (D₅). Earliest recognizable structures consist of recumbant isoclinal folds with a well-developed transposed foliation. This foliation is tightly folded about northwest trending, southwest verging second phase structures. Northwest trending third phase structures and northeast trending fourth phase structures occur as both crenulations and open buckles. Southeast dipping faults cut all earlier structures with tens of meters of normal offset Phase 1 and Phase 2 fold styles are compatible with a flattened buckle fold mechanism of formation, associated with elevated temperatures and reduced viscosity contrasts across layering. Later fold styles are controlled by higher viscosity contrasts and detachment along layering. All phases of deformation are dominated by semi-brittle mechanisms of dislocation slip and glide, mechanical twinning, and microcracking. Temperature activated diffusional creep is only locally active and does not contribute appreciably to total strain. The mineral assemblage garnet-staurolite-kyanite defines a metamorphic peak late in D₂. Metamorphic temperatures of approximately 530° C at 6.0 kb have been determined using garnet/biotite geothermometry. Extensive retrograde metamorphism spans D₃ and D₄, overprinting prograde assemblages and providing evidence for abundant fluids late in deformation. Late phase 1 diabase dykes locally intruded an area to the southeast of Ogden Peak. Major and trace element analyses of samples from these intrusions suggest a calc-alkaline, volcanic arc affinity.