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Flower visitation of fungus gnats from the genera Antlemom, Asindulum and Macrorrhyncha (Diptera: Keroplatidae): published data and a new record  [PDF]
Dimitar Bechev
ZooNotes , 2010,
Abstract: The literature data about flower visitation of species from the fungus gnats genera Antlemon, Asindulum and Macrorrhyncha are summarized and a new record for Macrorrhyncha flava on Heracleum verticillatum is given.
Estado del conocimiento taxonómico de la fauna de Chironomidae (Diptera: Nematocera) de la Patagonia Current state of the taxonomic knowledge of the Chironomidae fauna (Diptera: Nematocera) from Patagonia  [cached]
Mariano Donato,Julieta Massaferro,Stephen J. Brooks
Revista de la Sociedad Entomol?3gica Argentina , 2009,
Abstract: La familia Chironomidae (Diptera: Nematocera) es uno de los grupos de insectos más ampliamente distribuidos y abundantes en cuerpos de agua dulce. Los representantes de esta familia pueden explotar áreas con amplios gradientes ambientales. La información que se presenta está basada en la recopilación de datos distribucionales bibliográficos, del estudio del material tipo de las especies de Chironomidae depositadas en el Natural History Museum (UK) y del material de colección del Museo de La Plata (Argentina). En la Patagonia, se registran 9 subfamilias, la subfamilia monotípica Chilenomyiinae es endémica de esta área. Dentro de estas subfamilias, 53 de los 111 géneros conocidos para América del Sur están presentes en la Patagonia. Del total de géneros de la Patagonia, el 20 % es endémico y 7 de ellos muestran relaciones transantárticas. En la Patagonia, se registran 177 especies de Chironomidae, el 98% de éstas son endémicas, el 3 % son consideradas nomina dubia y el 17% requiere revisión ya que su ubicación sistemática es dudosa. Las descripciones originales de las especies patagónicas de Chironomidae están basadas principalmente sobre machos (n=58) y machos y hembras (n=43), ambas representan el 57% del total; el resto de las especies han sido descriptas con diferentes combinaciones de estadios del ciclo de desarrollo. The Chironomidae (Diptera: Nematocera) family is one of the most widely distributed group of insects and often the most abundant in freshwater environments. Representatives of this family can exploit a wide range of environmental gradients. The information here presented is based on the compilation of distributional data obtained from bibliography, the study of the type material deposited in the Natural History Museum (UK) and the collection material from Museo de La Plata (Argentina). Nine subfamilies are recorded from Patagonia, being the monotypic subfamily Chilenomyiinae endemic for the area. From the 111 known genera from South America, 53 are present in the studied area. Aproximately 20 % of the genera recorded from Patagonia are endemic and 7 of them have transantarctic relationships. In Patagonia there are 177 species of Chironomidae, out of which 98% are endemic, 3 % are considered nomina dubia and ca. 17 % requires revision since their systematic position is doubtful. The original descriptions of the chironomid species from Patagonia are based mainly on males (n=58) and males and females (n=43) both amounting to 57 % of the total, the rest of the species have been described using different combinations of stages from their lif
Estado del conocimiento taxonómico de la fauna de Chironomidae (Diptera: Nematocera) de la Patagonia
Donato,Mariano; Massaferro,Julieta; Brooks,Stephen J.;
Revista de la Sociedad Entomol?3gica Argentina , 2009,
Abstract: the chironomidae (diptera: nematocera) family is one of the most widely distributed group of insects and often the most abundant in freshwater environments. representatives of this family can exploit a wide range of environmental gradients. the information here presented is based on the compilation of distributional data obtained from bibliography, the study of the type material deposited in the natural history museum (uk) and the collection material from museo de la plata (argentina). nine subfamilies are recorded from patagonia, being the monotypic subfamily chilenomyiinae endemic for the area. from the 111 known genera from south america, 53 are present in the studied area. aproximately 20 % of the genera recorded from patagonia are endemic and 7 of them have transantarctic relationships. in patagonia there are 177 species of chironomidae, out of which 98% are endemic, 3 % are considered nomina dubia and ca. 17 % requires revision since their systematic position is doubtful. the original descriptions of the chironomid species from patagonia are based mainly on males (n=58) and males and females (n=43) both amounting to 57 % of the total, the rest of the species have been described using different combinations of stages from their life cycle.
TAXONOMICSTUDIESONTHESCIARIDAE(PIPTERA:NEMATOCERA)OFGUIZHOU  [PDF]
昆虫分类学报 , 1993,
Abstract: ThefamilySciaridaeofGuizhouProvincecontains10generaand57species,ofwhich1genusand43speciesarenewtoscience.Thenewtaxaaredescribedintaxonomickeys.ThetypespecimensarekeptintheInsectCollectionofBeijingAgriculturalUniver-sity.Thelettersgivenherearelocalityabbreviationsusedinthegenusandspecicslistthatfollows.
Two New Species of Fungus Gnats of the Genus Apemon  [cached]
Charles W. Johnson
Psyche , 1931, DOI: 10.1155/1931/74510
Abstract:
The Jurassic of Denmark and Greenland: The Jurassic of the Netherlands  [PDF]
Herngreen, G.F. Waldemar,Kouwe, Wim F.P.,Wong, Theo E.
Geological Survey of Denmark and Greenland Bulletin , 2003,
Abstract: A recent revision of the lithostratigraphy of the Netherlands has triggered an extensive re-evaluation of existing ideas on the Jurassic structural and depositional history. Significant advances can be attributed to the incorporation of sequence stratigraphic concepts. In the course of the Triassic and Jurassic, structural complexity increased progressively. The Jurassic sedimentary succession can be subdivided into three depositional megasequences. Megasequence I (Rhaetian- Aalenian) reflects the period between the so-called early and mid-Cimmerian tectonic phases. Megasequence II (Aalenian - Middle Callovian) covers the period of activity of the mid-Cimmerian phase. Megasequence III (Middle Callovian - Ryazanian) corresponds with the period between the mid-Cimmerian and late Cimmerian phases (particularly after pulse II). In this latter megasequence, six stages (IIIa-f) are recognised. Sediments deposited during the Rhaetian and Ryazanian bear a stronger affinity with the Jurassic succession than with Triassic and Cretaceous sediments respectively. These stages are thus treated here as an integral part of the Jurassic succession. During the Rhaetian-Bajocian the area subsided relatively uniformly. A sheet of predominantly fine-grained marine sediments of great lateral uniformity was deposited. During the Toarcian, in particular, basin circulation was largely restricted. The cooling that followed the thermal Central North Sea dome uplift triggered an important extensional phase during the Aalenian-Callovian. The rift phase resulted in the formation of several smaller basins, each with its own characteristic depositional succession. The basins fall into three structural provinces: the eastern province (Lower Saxony Basin, E-W-striking); the northern province (Central Graben, N-S-striking); and the southern-central system (Roer Valley Graben - Broad Fourteens, with a strong NW-SE strike). The mid-Cimmerian event started to affect the Dutch basins during the Bajocian. Sedimentation ceased in the Dutch Central Graben while it persisted in a predominantly coarse-grained, shallow marine facies in the southern basins (Roer Valley Graben, West Netherlands Basin). Extensional tectonics in the Central Graben were initiated during the Middle Callovian, with the deposition of continental sediments. During the Oxfordian-Kimmeridgian, marine incursions gradually became more frequent. Marine deposition in the other basins in the south persisted into the Oxfordian, at which time deposition became predominantly continental. Marine conditions gradually returned in the s
New records of Simuliidae (Diptera, Nematocera) in the State of S?o Paulo, Brazil
Pepinelli, Mateus;Trivinho-Strixino, Susana;Hamada, Neusa;
Revista Brasileira de Entomologia , 2003, DOI: 10.1590/S0085-56262003000400020
Abstract: adult and immature simuliidae were studied in 31 streams of 8 regions of the state of s?o paulo. among the 25 species collected, seven are new records for the state of s?o paulo, and one of them, simulium shewellianum coscarón, 1985 for brazil as well.
Estado actual del conocimiento de la familia Ceratopogonidae en la Patagonia (Diptera: Nematocera) Current knowledge of the family Ceratopogonidae in Patagonia (Diptera: Nematocera)  [cached]
Gustavo R. Spinelli,Pablo I. Marino
Revista de la Sociedad Entomol?3gica Argentina , 2009,
Abstract: Ceratopogonidae incluye peque os dípteros nematoceros que crían en hábitats acuáticos o semiacuáticos. Hasta los '80, el conocimiento de su taxonomía en la Patagonia se hallaba limitado a la contribución de los comienzos de los '30 de Ingram y Macfie, sobre la base de material capturado en 1926-27, en el área del Parque Nacional Nahuel Huapi y zonas vecinas de Chile. En los últimos 25 a os, se pusieron en marcha diferentes proyectos, resultando la descripción o registro de numerosos taxones para la región. Si se contabilizan los datos publicados, 102 especies habitan en la Patagonia, de las cuales 86 (84,31%) son endémicas para la región. Este alto porcentaje es evidente en los bosques de Nothofagus, con 71 especies endémicas de este bioma, nueve lo son de la estepa y seis presentan registros en bosque y estepa. Datos aún no publicados concuerdan con este esquema. Diecinueve géneros están representados en la Patagonia, diez de ellos con amplia distribución, tres de distribución transantártica y seis son endémicos para el área. Para la misma, se hallan publicadas las revisiones de Forcipomyia, Atrichopogon, Borkenthelea, Macrurohelea y Paradasyhelea; se han finalizado y aún no publicado aquellas de Dasyhelea y Palpomyia, está muy avanzada la de Stilobezzia y se prevé comenzar con las de Austrohelea, Austrosphaeromias, Physohelea y Bezzia. Se calcula que estos datos no divulgados contienen al menos 55 especies todavía no descriptas. Con respecto a los aspectos biogeográficos se pueden destacar estudios que tienden a establecer relaciones entre las áreas reconocidas en esquemas biogeográficos propuestos para la región andina. Ceratopogonidae includes small nematoceran Diptera which breed in aquatic and semiaquatic habitats. Until the 80′s its taxonomic knowledge in Patagonia was limited to the early 30′s contribution of Ingram and Macfie, from material collected in 1926-27 in the area of the Nahuel Huapi National Park and neighboring sites of Chile. During the last 25 years several projects were performed, many new taxa were described or firstly recorded from the mentioned area. Considering the published data, 102 especies inhabit Patagonia, out of which 86 (84,31%) are endemic. This high percentage is evident in the Nothofagus forests with 71 endemic species, nine are endemic from the steppe and six occur in both biomas. Unpublished data is consistent with this squeme. Nineteen genera are represented in Patagonia, ten widely distributed, three exhibiting transantarctic distribution and six endemic of Patagonia. Revisions of Forcipomyia, Atrichopogon, Bork
Serine protease Jurassic Park
Cathy Holding
Genome Biology , 2003, DOI: 10.1186/gb-spotlight-20030903-01
Abstract: Wouters et al. inferred ancestral sequences from parsimony analysis of a multiple alignment of 56 immune defense protease (IDP) sequences and constructed a synthetic gene to express the recombinant protein that they called Stemzyme-IDP-β. Using angiotensin II as substrate for kinetic and binding studies, the authors observed high catalytic efficiency and broad substrate specificity and a tolerance to mutation at the binding site, with different mutations resulting in activities similar to some of the synthetic enzyme's descendents. They suggest that a form of reverse evolution must have occurred that provided a mechanism for enzymes with narrow specificity to evolve from enzymes with already narrow specificity."Our findings... suggest that once a narrow primary specificity had become established, the further generation of diversity required a reversion to the presumed original state. That is, despecialization or evolution-in-reverse was required for further diversification," the authors conclude.
Ammonite biostratigraphy of the jurassic of Tanzania
S Kapilima
Tanzania Journal of Science , 2003,
Abstract: The present paper summarizes the previous biostratigraphical researches and incorporates the recent research findings on the Jurassic rocks in the coastal basin of Tanzania. The ammonites used for the biostratigraphical classification are from two sub-basins along the coastal belt of Tanzania: Mandawa (south) and Ruvu- Tanga (north). The oldest known ammonites from these basins are of Aalenian age. The biostratigraphical classification of the Jurassic sequence, on the basis of the vertical and horizontal distributions of the ammonite assemblages, permits the erection of eight sub stages of Jurassic: Upper Aalenian (Concavum-Zone), Bajocian (Humphrieasianum-Zone), Middle Callovian (Coronatum-Jason Zone), Upper Callovian (Lamberti-Athleta Zone), Lower Oxfordian (Cordatum-Mariae Zone), Middle Oxfordian (Transversarium-Zone), Lower Kimmeridgian (Tenuilobatus-PlatinotaZone)and Upper Kimmeridgian-Tithonian (Beckeri-Zone). This fauna assemblage forms an intergral part of the Indo-Madagascar Province and the Trans-Erythraean-Trough. Tanz. J. Sci. Vol.29(2) 2003: 27-34
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