Pyramidal spiriferids (brachiopods) from the Middle and Upper Devonian of the Russian Plate: Morphology, systematics, and shell wall structure

The pyramidal spiriferids Thomasaria Stainbrook, 1945 and Pyramina Ljaschenko, 1969 from the collection of brachiopods of Ljaschenko are examined. New data on the shell microornamentation and inner structure support the validity of the genus Piramina and its type species P. oskolensis Ljaschenko. A new species of the genus Thomasaria, T. rotunda is described.     

Systematics and shell microstructure of the spiriferid genera Echinospirifer and Komispirifer from the Upper Devonian of southern Timan

The type species of the genera Echinospirifer Ljaschenko, 1973 Komispirifer Ljaschenko, 1973 and Mennespirifer Ljaschenko, 1973 were revised based on material from the memorial collection of A.I. Ljaschenko. Mennespirifer is recognized as a junior synonym of the genus Komispirifer; the genera Echinospirifer and Komispirifer differ in fine ornament and the structure of the shell wall.     

Shell structure of punctate spiriferids (Brachiopoda) from the East European Platform

The shell structure of the Devonian punctate spiriferids Theodossia Nalivkin, 1925, Pyramina Ljaschenko, 1969, Warrenella Crickmay, 1953, Eoreticularia Nalivkin, 1930, Thomasaria Stainbrook, 1945 from the order Spiriferida Waagen, 1883, and also Cyrtina Davidson, 1858 and Punctospirifer North, 1920 from the order Spiriferinida Ivanova, 1972 from the Devonian and Carboniferous of the East European Platform is described.     

Spiriferid genus Warrenella from the Upper Devonian of Southern and Middle Timan

Nordella orbiculata (Ljaschenko, 1959) and N. subquadrata Ljaschenko, 1973 are revised based on the topotypical material from the collection of A.I. Ljaschenko. Based on data on the morphology, microornamentation, and shell structure Nordella is shown to have characters closely similar to Warrenella Crickmay, 1953 and, therefore, should be considered as its junior synonym. A new species, W. timanimedia sp. nov., is described from the Upper Devonian of Middle Timan.     

Continuing of the revision of Spriferid (Brachiopoda) zonal species from the Frasnian Stage (Upper Devonian) of the Russian Platform

Adolfia siratschoica (Ljaschenko) and Adolfia krestovnikovi (Ljaschenko) are accepted as zonal species of the Petino and Voronezh Horizons of the Frasnian Stage of the Russian Platform. However it was established that these species do not belong to the genus Adolfia. The former species was recognized as the nomenclatural type species of Ljaschenkovia gen. nov. and the latter species was recognized as the type species of Tokmospirifer gen. nov. The comparative analysis provided of the shell structure, microornamentation, and shell interior of the type species of Ljaschenkovia gen. nov., Tokmospirifer brevis gen. et sp. nov., and Adolfia solita Ljaschenko is presented.     

New spiriferids (Brachiopoda) from the Lower and Middle Devonian of northeastern Russia

New spiriferids (Brachiopoda) are described from the Lower and Middle Devonian of northeastern Russia: Tatjanaspirifer iskrensis sp. nov. and T. magnificus sp. nov. (family Reticulariidae); Cyrtina inveterata Baranov, sp. nov. and Blodgettospirifer gen. nov. with type species B. lezhoevi sp. nov. (family Cyrtinidae).     

The genus <Emphasis Type="Italic">Unispirifer</Emphasis> Campbell (Brachiopoda,Spiriferida) in the Early Carboniferous of the Moscow Syneclise

Two new species of the genus Unispirifer Campbell, U. semicircularis and U. parvus, are established as a result of a revision of Early Carboniferous spiriferids from the Moscow Syneclise. These forms have previously been described under Spirifer tornacensis Koninck, 1883 and S. taidonensis Tolmatschow, 1924.     

Sequential function of gene products relative to DNA synthesis in the yeast cell cycle

An experimental rationale for deciphering the relative dependence of steps in a developmental pathway (Jarvik & Botstein, 1973; Hereford & Hartwell, 1974) has been employed to determine the relationship between the hydroxyurea-sensitive step and various temperature-sensitive steps in the cell cycle of Saccharomyces cerevisiae. Since hydroxyurea inhibits DNA replication in yeast (Slater, 1973), the data identify gene products upon whose function DNA replication is dependent (cdc 4, 6, 7, 2, 8, 21) and gene products whose function or synthesis requires DNA replication (cdc 2, 8, 21, 9, 13, 16, 23, 5, 15). Other gene products (cdc 3, 11, 24) function independent of DNA replication. These results suggest that the events of the cell cycle occur in a proscribed order because many of the gene products that mediate these events arc restricted to a prescribed sequence of function.Mutations in two genes (cdc 2 and 6) result in cells that remain sensitive to hydroxyurea after an incubation at the restrictive temperature, despite the fact that both mutants incorporate radioactive precursors into DNA at the restrictive temperature (Hartwell, 1973). It is suggested that cdc 6 specifies a function that is necessary for the proper initiation of DNA replication, and cdc 2 a function that is necessary for correct DNA elongation, and that in the absence of either of these functions the DNA that is made is either faulty or incomplete.     

The stratigraphic distribution of organic-walled dinoflagellate cysts in the Cretaceous and Tertiary

All information concerning the stratigraphic distribution of organic-walled dinoflagellate cysts in the Cretaceous and Tertiary sediments of the world, published prior to 1974, has been critically assessed. Stratigraphically reliable records are presented in tabular form; stratigraphical subdivision to stage or formation is incorporated wherever possible. Records of doubtful authenticity are commented on and questions of stratigraphic and taxonomic interest are discussed in the text.A new family, Family Florentiniaceae nov. fam., is erected, and the following new taxonomic combinations are proposed: Astrocysta ampla (Harland, 1973) nov. comb.; Cooksoniella larjakense (Vozzhennikova, 1967) nov. comb.; ?Florentinia truncigera (Deflandre, 1937b) nov. comb.; Phthanoperidinium pannonium (Lentin and Williams, 1973) nov. comb.; Spiniferites scabrosus (Clarke and Verdier, 1967) nov. comb. and Veryhachium hermesinoides (O. Wetzel, 1940) nov. comb., the latter being now considered to be an acritarch.The rejection is proposed of the following species, which were nomenclaturally superfluous when published: Astrocysta koslowskii (Górka 1963) Davey, 1970; Gonyaulacysta fragosa Brideaux, 1971; Hystrichosphaeridium brideauxi Lentin and Williams, 1973; Oligosphaeridium diastema Singh, 1971 and Pseudoceratium regium Singh, 1971. Reasons are given for the rejection of the following generic reallocations: Hystrichodinium voigti (Alberti, 1961) Corradini, 1973 and Tenua anaphrissa (Sarjeant, 1966c) Benedek, 1972. Rhombodinium Gocht, 1955 is considered to be best treated as a subgenus of Wetzeliella Eisenack, 1938 emend. Williams and Downie, 1966b as originally proposed by Alberti, 1961.     

Four Decades of Forest Persistence,Clearance and Logging on Borneo

The native forests of Borneo have been impacted by selective logging, fire, and conversion to plantations at unprecedented scales since industrial-scale extractive industries began in the early 1970s. There is no island-wide documentation of forest clearance or logging since the 1970s. This creates an information gap for conservation planning, especially with regard to selectively logged forests that maintain high conservation potential. Analysing LANDSAT images, we estimate that 75.7% (558,060 km²) of Borneo''s area (737,188 km²) was forested around 1973. Based upon a forest cover map for 2010 derived using ALOS-PALSAR and visually reviewing LANDSAT images, we estimate that the 1973 forest area had declined by 168,493 km² (30.2%) in 2010. The highest losses were recorded in Sabah and Kalimantan with 39.5% and 30.7% of their total forest area in 1973 becoming non-forest in 2010, and the lowest in Brunei and Sarawak (8.4%, and 23.1%). We estimate that the combined area planted in industrial oil palm and timber plantations in 2010 was 75,480 km², representing 10% of Borneo. We mapped 271,819 km of primary logging roads that were created between 1973 and 2010. The greatest density of logging roads was found in Sarawak, at 0.89 km km⁻², and the lowest density in Brunei, at 0.18 km km⁻². Analyzing MODIS-based tree cover maps, we estimate that logging operated within 700 m of primary logging roads. Using this distance, we estimate that 266,257 km² of 1973 forest cover has been logged. With 389,566 km² (52.8%) of the island remaining forested, of which 209,649 km² remains intact. There is still hope for biodiversity conservation in Borneo. Protecting logged forests from fire and conversion to plantations is an urgent priority for reducing rates of deforestation in Borneo.     

Invasion or retreat? The fate of exotic invaders on the northern prairies, 40?years after cattle grazing

Despite the detrimental impacts of invasive plants on native biodiversity, ecosystem function, and management cost, few studies have focused on the long-term persistence of invaders. Here, we use a unique, long-term dataset to examine the recovery of northern rough fescue prairie communities, 41?years after the removal of livestock from Riding Mountain National Park, Manitoba, Canada. Our 1973 data suggest that summer grazing of plains?? rough fescue (Festuca hallii (Vasey) Piper) leads to its displacement from the plant community and increased dominance by exotic invaders. After 41?years of recovery time, historic grazing intensity remained an excellent predictor of community structure and composition. Areas classified as heavily grazed in 1973 remained characterized by exotic grasses and had significantly lower richness and diversity. While some exotic invaders persisted despite 41?years of community recovery, others were ephemeral. For example, both Poa pratensis (L.) and Bromus inermis (Leyss.) persisted, increasing in abundance across all classes of grazing intensity, suggesting that their control requires active restoration of the invaded areas. In contrast, passive restoration may be possible for a subset of ephemeral exotic species such as Taraxacum officinale, which had virtually disappeared from invaded prairies by 2010. Our long-term data provide a rare perspective into the long-term dynamics of plant invasions. Based on our findings, conservation managers will need to consider the dichotomy between persistent and ephemeral invaders and their impact on the recovery of northern prairie communities as they focus their restoration efforts against the mounting impacts of exotic plant invaders.     

On travelling wave solutions in a model for the Belousov-Zhabotinskii reaction.

DNA fragments partially digested by a 3′- or 5′-specific nuclease to produce single chain ends of opposite polarity will form a ring if the ends contain complementary sequences and are allowed to anneal. The frequency of rings can then be used as an assay to determine where and how identical repetitious sequences are arranged in the DNA. Thomas et al. (1973b) showed that all eucaryote chromosomes studied contain similar if not identical repetitious sequences clustered into regions called g-regions. To account for the observed ring frequency under different experimental conditions Thomas, Zimm &; Dancis (1973c) derived equations for two possible models of g-region organization. In the pure tandem model, the repetitious sequences are contiguous and occupy the entire g-region. In the intermittent repetition model, the repetitious sequences are simple copolymers and are irregularly arranged among non-repetitious sequences which are heterogenous in length. In the present paper, the results of Thomas et al. (1973c) are extended to cover the fractional tandem model. In this model, adjacent repetitious sequences are separated by non-repetitious sequences of uniform length. In addition, the equations for both the pure tandem and intermittent repetition models are shown to be special cases of the fractional tandem model but not vice versa.The capabilities and limitations of an analysis of ring formation are demonstrated using data from Drosophila. Although it is not possible to rule out any of the three models, the analysis can limit the ranges of the parameters describing each of the models that are consistent with the data. Previous conclusions that the data could only be explained by a pure tandem model which lacks any intervening unique sequences (Bick, Huang &; Thomas, 1973; Thomas et al., 1973b), are shown to be incorrect, in part because the equations for the fractional tandem model had not then been derived. Thus ring theory equations can be used to show the presence of clusters of similar if not identical sequences from ring-forming experiments, but they may not be able to determine the exact spacing and arrangement of these sequences within the clusters.     

Towards the integrated control of Korean citrus pests

Research on Korean citrus pests has received little attention in the past. This paper describes studies suggesting that an integrated control system is feasible. Population fluctuations of citrus insects were studied intensively in 1973 and 1974. In unsprayed trees a population outbreak ofPanonychus citri (Mc Gregor) in 1973 declined sharply following the activity ofOligota yasumatsui Kistner (Staphylinidae) and other predators, to remain at low densities for the rest of the season. In 1974 a smaller outbreak was apparently again checked by predators. With negligible rates of parasitism there was a gradual rise in the numbers ofCeroplastes rubens Maskell which is probably a key pest. In a farmer's grove receiving 7–8 annual sprays,P. citri populations were higher at the end of each season than in unsprayed trees.Phyllocnistis citrella Stainton severely attacked the summer flush in sprayed and unsprayed groves equally, no parasitism being observed. Other citrus pests observed were unimportant and many were frequently parasitized. In an experiment in 1973, trunk applications of monocrotophos did not controlP. citri orP. citrella. Flushing rhythm consists of a heavy spring flush followed by a 2nd lighter flush in summer.     

Theoretical approach to the functional optimisation of spiriferide brachiopod shell: Optimum morphology of sulcus

Evidence suggests that biological forms that provide physiological and autecological functions have evolved to adapt to environmental conditions and to optimise requisite morpho-functions. We examined whether shell morphology is functionally optimised to generate passive feeding flow in the Devonian spiriferide brachiopod Paraspirifer bownockeri. This study was based on quantitative results from a computational fluid dynamics simulation and the Lagrangian multiplier method. We estimated the optimum development of the ventral median shell depression, which is called the sulcus, by minimising the pressure difference along the gape. This estimation was made under the constraint that the number of spiral flow rotations must be greater than one, which is effective for spiriferide feeding because of its alignment with the spiral lophophore. During mathematical optimisation, the equation resulted in a suitable flow velocity of approximately 0.1 m/s. At this velocity, the pressure difference was minimised, regardless of sulcus development. The constraint equation showed that the number of spiral flow rotations increased with sulcus development. The optimal solution was similar to the original sulcus form of Paraspirifer under an ambient flow of approximately 0.1 m/s. This result suggests that the variation of shell outline in spiriferids could provide a variety of preferential conditions for ambient flow and that the flow intensity could be adjusted by sulcus development to generate a robust passive feeding flow along the spiral feeding organs.     

Birth of two second generation hybrid macaques

A male infant was born to a hybrid female monkey (Macaca mulatta × M. nemestrina) on 24 May 1973. On 4 July 1973, a second hybrid female macaque (M. nemestrina × M. nigra) also produced a viable female infant. These were the twenty-seventh and twenty-eighth hybrid births in our program, but the first second generation births.     

Revision of the planthopper genus Nycheuma Fennah (Hemiptera,Fulgoromorpha, Delphacidae)

Chinese species in the genus Nycheuma Fennah, 1964a (Hemiptera: Fulgoromorpha: Delphacidae: Delphacinae: Delphacini) are revised to include three species: Nycheuma cognatum (Muir, 1917), Nycheuma dimorpha (Matsumura, 1910) and Nycheuma nilotica Linnavuori, 1973. Nycheuma coctum Yang, 1989 is placed in synonymy with Nycheuma nilotica Linnavuori, 1973. Nycheuma dimorpha (Matsumura, 1910) is newly recorded from China. The generic characteristics are redefined. The main morphological characters, male genitalia of 3 species are described or redescribed and illustrated. A key to Chinese species in the genus is provided.     

A supplement to the grassfly fauna of Japan (Diptera, Chloropidae)

Two new grassfly species, Gampsocera diversicolor closely related to G. tenuisinuosa Kanmiya, 1983 and Conioscinella subdivitis closely related to C. divitis Nartshuk, 1971, are described from Japan. Keys for the new species are given. Oscinisoma ussuriense Nartshuk, 1973, known in Primorskii Territory of Russia and Korea, was found in Japan (Honshu Island) for the first time. The genus Oscinisoma Lioy, 1864 was also first recorded in Japan.     

Seaweed biodiversity in the south-western Antarctic Peninsula: surveying macroalgal community composition in the Adelaide Island/Marguerite Bay region over a 35-year time span

The diversity of seaweed species of the south-western Antarctic Peninsula region is poorly studied, contrasting with the substantial knowledge available for the northern parts of the Peninsula. However, this is a key region affected by contemporary climate change. Significant consequences of this change include sea ice recession, increased iceberg scouring and increased inputs of glacial melt water, all of which can have major impacts on benthic communities. We present a baseline seaweed species checklist for the southern Adelaide Island and northern Marguerite Bay region, combining data obtained during a small number of surveys completed in 1973–1975 and a 6-week intensive diving-based field campaign in 2010–2011. Overall, with a total of 41 macroalgal species recorded (7 brown, 27 red, 6 green, 1 chrysophyte), the region is species-poor compared to the north of the Antarctic Peninsula, and even more so in comparison with the sub-Antarctic. The key canopy-forming species is Desmarestia menziesii, which is abundant in Antarctic Peninsula waters, but lacking in the sub-Antarctic. Himantothallus grandifolius, which is a common species further north in the Antarctic phytobenthos, was absent in our recent collections. This paper also reports the first record of Aplanochytrium sp. (Labyrinthulomycetes) from this part of Antarctica and in association with Elachista sp.     

Batwanema gen. n. and Chokwenema gen. n. (Oxyurida,?Hystrignathidae), new nematode genera?as parasites of Passalidae (Coleoptera) from the Democratic Republic of Congo

Two new genera and species parasitizing passalid beetles from the Democratic Republic of Congo are described. Batwanema congo gen. n. et sp. n. is characterized by having females with the cervical cuticle armed with scale-like projections, arranged initially in rows of eight elements that gradually divide and form pointed spines toward the end of the spiny region, two cephalic annuli, clavate procorpus and genital tract monodelphic-prodelphic. Two Malagasian species of Artigasia Christie, 1934 were placed in this genus as B. latum (Van Waerebeke, 1973) comb. n. and B. annulatum (Van Waerebeke, 1973) comb. n. Chokwenema lepidophorum gen. n. et sp. n. is characterized by having females with the cervical cuticle armed with scale-like projections, arranged initially in rows of eight elements (similar to Batwanema) that divide gradually, forming spines; a single cephalic annule cone-like, truncated, moderately inflated; procorpus sub-cylindrical and genital tract didelphic-amphidelphic.     

New and little-known grylloblattids of the family Geinitziidae (Insecta: Grylloblattida) from the Triassic and Jurassic of Europe,Asia, and South Africa

The fossil history of the family Geinitziidae is reviewed. New taxa are described in the family: Shurabia hissarica, sp. nov. (Lower Jurassic of Tajikistan), Sh. shartegica, sp. nov. (Upper Jurassic of Mongolia), Sh. serrata, sp. nov. and Ginitzia sagulensis, sp. nov. (both Lower Jurassic of Kyrgyzstan). The subfamily Stegopterinae Sharov, 1961 is synonymized under Geinitziinae Handlirsch, 1906. The genera Minesedes Fujiyama, 1973 and Ominea Fujiyama, 1973 (Upper Triassic of Japan) are synonymized under Shurabia Martynov, 1937 and Geinitzia Handlirsch, 1906, respectively. Geinitzia varia Bode, 1953 (Lower Jurassic of Germany) and Fletchizia picturata Riek, 1976 (Upper Triassic of South Africa) are redescribed from their holotypes. F. kapokraalensis Wappler, 2001 and F. aleda Wappler, 2001 (both Upper Triassic of South Africa) are transferred to the genus Shurabia.