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A possible episode of coevolution between galling insects and plants is reported. It was identified by a high infestation (density) of fossil gall found on the compressed Dicroidium Flora from the Triassic (Ladinian–Carnian) Passo das Tropas Member, Santa Maria Formation, Parana Basin. The galls were found on phytofossils in 2.2 m thick mudstones with horizontal lamination, intercalated between coarse and medium-grained sandstones with clasts and cross-lamination at the base and top of the section. The associations were identified with a stereomicroscope, after which they were quantified within each botanical group, along with their type, in order to calculate the average number of galls per leaf (density). The overall density found was 4.018. Corystospermales was the predominant botanical group (87.81%), with a gall density of 4.281, followed by Ginkgoales, Equisetales, and Incertae sedis. Current ecological studies indicate that a xerophytic paleoenvironment correlates with high infestations of galling insects. However, many taphonomic, biological, and ecological factors may be involved, resulting in different hypotheses from the same data. On the other hand, they support the interpretations of this record in other aspects discussed. Furthermore, the identified gall density can be interpreted from a paleobiogeographical perspective, showing dispersion at low altitudes and intermediate subtropical latitudes (25o to 38o S or N).

Fil: Cabral Kloster, Adriana. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Nordeste. Centro de Ecologia Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecologia Aplicada del Litoral; Argentina

The analysis of insect-plant interaction can be provide paleoecological and paleoenvironmental important data for understanding the co-evolution between plants and insects. Since the appearance of ...

Malacostracan crustaceans of the fossil order Pygocephalomorpha are conspicuous elements in brackish to freshwater faunas in the upper Carboniferous of Laurentia and lower Permian of Gondwana. A pronounced sexual dimorphism is recognizable within its members, with Pygocephalomorpha females bearing oostegites: modified epipodites that hold a brood pouch where the eggs develop until juvenile stage, with no planktonic dispersal of larvae. The preservation of oostegites is quite rare and is described here for the first time from the American continents. The specimens, ventrally preserved Liocaris huenei females bearing oostegites, come from the Irati Formation, a lower Permian sequence of the Parana Basin, from an outcrop in southern Brazil. The oostegites are similar to those previously described for Pygocephalomorpha, displaying seven pairs of overlapping epipodites that cover the whole cephalothorax. The scarcity of these structures in the fossil record may be explained by taphonomic bias (it requires ventrally preserved crustaceans) but more likely by palaeobiological aspects, such as preservation of an ovigerous moult. The record from the Irati Formation suggests that pygocephalomorphs had seasonal reproduction, with females maturing at the same time and acquiring oostegites that would be lost after the release of juveniles. This record confirms the relationship of the Brazilian Liocaris Beurlen to the English Pygocephalus Huxley and South African Notocaris Broom pygocephalomorphs and provides an insight into its palaeoecological significance.

This paper reports the first record of Triassic insect oviposition scars from southern South America. These scars are found on Late Triassic leaves and leaf fragments from Heidiphyllum elongatum Retallack and Pseudoctenis harringtoniana Bonetti, from the La Ternera Formation, and Taeniopteris sp. B from the Las Breas Formation, in northern Chile. The morphology of these traces is described in detail and comparisons are made with other worldwide records. The identified scars from the Triassic of Chile are: Paleoovoidus contactus isp. nov., P. megaovoidum isp. nov. and P. rectus (Vasilenko) Sarzetti, Labandeira, Muzón, Wilf, Cuneo, Johnson, Genise. Additionally, P. midribum isp. nov., P. marginatum isp. nov., and P. oppositum isp. nov. are established, based upon a detailed analysis of descriptions in the literature. A synthesis of the geological records and ichnotaxonomic considerations is given. The five new species are defined based on the ichnotaxonomic characters suggested by various authors, with the objective of standardizing the different schemes under a single binomial ichnotaxonomical proposal, including all records from the Carboniferous to the Cenozoic, and establishing the corresponding synonymy. Ichnofossils from the Triassic of Chile are tentatively assigned to the Order Odonatoptera based upon morphological characteristics their host plants, and palaeoenvironmetal interpretations. Fil: Gnaedinger, Silvia Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentina Fil: Adami-Rodrigues, Karen. Universidade Federal de Pelotas; Brasil Fil: Gallego, Oscar Florencio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentina. Universidad Nacional del Nordeste. Facultad de Ciencias Exactas Naturales y Agrimensura; Argentina

This study provides the first evidence for plant- insect associations from fossil leaf impressions of the San Jose and Palo Pintado formations, dated as middle and upper Miocene age, from northwestern Argentina. The size, shape and arrangement of leaf damage on several plant hosts consists of various chew marks made by mandibulate insects occurring along the leaf blades of Malvaciphyllum quenquiadensis Anzotegui and Cristalli (Malvaceae), hole feeding along the leaf edge of Nectandra saltensis Anzotegui (Lauraceae), mines within the internal tissues of M. quenquiadensis, and oviposition scars in Cedrela sp. (Meliaceae). Based on specific, identifiable features of the plant damage, the likely producers responsible for this damage include external foliage feeders such as Orthoptera, Phasmoptera and Coleoptera; leaf miners from the Lepidoptera but possibly Hymenoptera and Diptera; and ovipositing insects representing the Odonata. Many of these insect groups were previously known from earlier Paleogene deposits of Argentina, and similar ovipositional damage has been documented from the early Eocene of Rio Negro and middle Eocene of Chubut in Patagonia, indicating geochronological continuity and occurrence in marsh and open woodland plant communities under warm and seasonal climatic conditions.

Detailed descriptions are provided for specimens of a new genus Zygiaxylon nov. gen. et sp. and Swartzioxylon naraense Delteil-Desneux from the Solimões Formation (Miocene), Acre Basin, western Amazon, Brazil. These fossil woods present an affinity with the family Leguminosae. Anatomical characteristics of the woods show a resemblance with the extant genera Swartzia Schreb and Zygia P. Browne, respectively. These genera currently have a wide distribution in Brazil and throughout the entire Amazon region, and their presence in the outcrop tops of the Solimões Formation supports the idea that these morphogenera might have been important components of the Miocene mesomorphic flora in the Amazon forests. Descrições detalhadas são fornecidas para os espécimes de um novo gênero e espécie de Mimosoideae e Swartzioxylon naraense Delteil-Desneux emend. (Papilionoideae) da Formação Solimões, Mioceno, bacia do Acre, Brasil. Características anatômicas das madeiras mostram uma semelhança com os gêneros viventes Zygia P. Browne e Swartzia Schreb, respectivamente. Esses gêneros têm atualmente uma ampla distribuição no Brasil e em toda a região amazônica, sua presença nos afl oramentos da Formação Solimões suporta a ideia de que poderiam ter sido importantes componentes e indica a sua importância no registro fóssil, tanto para estabelecer sua distribuição e evolução do passado ao presente da flora amazônica. Fil: Cabral Kloster, Adriana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentina Fil: Gnaedinger, Silvia Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Centro de Ecología Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecología Aplicada del Litoral; Argentina Fil: Adami Rodrigues, Karen. Universidade Federal de Pelotas; Brasil Fil: Urbam, Camile. Universidade Federal de Pelotas; Brasil

A new record of fossil wood to the Valley of Jurua, Solimoes Formation, Southwestern Amazon, is analyzed. The fossil material came from one of the countless outcrops found along the Jurua River. The wood described presents anatomical affinities with the Fabaceae and more specifically with Zollernioxylon tinocoi Mussa. This new record confi rms the presence of the Fabaceae in the past vegetation of Amazon and by its comparison with modern vegetation contributes to the paleoenvironmental reconstructions of the region. Key words: fossil wood, Fabaceae, Miocene, Jurua Valley, Acre Basin, Brazil.

A análise quantitativa de 16.291,29 cm² de superfície foliar de 352 espécimes da "Flora Glossopteris" coletados na Formação Rio Bonito (Artinskiano/Kunguriano da bacia do Paraná) revelou que 8,24% destes foram atacados por insetos herbívoros. Os valores das áreas herbivorizadas e das áreas preservadas foram utilizados na obtenção, por táxon e afloramento, da proporção da área removida por herbivoria e do índice de herbivoria, cujos resultados variam entre 0,24 – 2,97% e 0,25 – 2,95%, respectivamente. Folhas notófilas de glossopterídeas, especialmente do morfo-gênero Glossopteris, foram os tipos foliares mais atacados, seguidos de megáfilos de Cordaites. Nas três localidades estudadas (afloramentos de Quitéria, Mina do Faxinal e Mina do Morro do Papaléo), os diferentes índices de herbivoria detectados permitiram estabelecer relações entre as paleofloras e os paleoambientes deposicionais associados, além de comparações com os padrões das floras modernas. Entre os paleoambientes identificados, os de vegetação desenvolvida em área pantanosa, margem de corpos lacustres e de planície de inundação foram os únicos que apresentaram indícios de herbivoria. The quatitative analysis of 16,291.29 cm² of foliar surface of 352 specimens of the "Flora Glossopteris" recorded from the Rio Bonito Formation (Artinskian/Kungurian of the Paraná basin) revealed that 8,24% of the leaves were attacked by herbivorous insects. The values of foliar herbivorized and preserved areas were utilized to obtain, by taxa and outcrop, the proportion of herbivorized removed area and the herbivory index, whose results range between 0.24 – 2.97% and 0.25 – 2.95% respectively. Notophylls of glossopterids were the most attacked of the foliar types, in special the morphogenus Glossopteris followed by the megaphylls of Cordaites. Different rates of herbivory were found from the three outcrops studied (Quitéria, Faxinal Quarry and Morro do Papaléo Quarry) and suggested relationship between the paleofloras and the associated depositional paleoenvironments as well as comparison with current herbivory standards. Among the identified paleoenvironments, the ones developed in swampy areas, lacustrine margins and inundation plains were the only ones presenting signs of herbivory.

New data on Pygocephalomorph Crustacea is provided, together with a historical analysis of previous work on the group. Pygaspis brasiliensis Beurlen, 1934, from the Permian Iratí Formation of Brazil is redescribed and compared with South African pygocephalomorphs.