Roberto Iannuzzi

A Pre-Glacial, Warm-Temperate Floral Belt in Gondwana (Late Visean, Early Carboniferous)

Abstract Unusual fossil macrofloras from South America (Peru, Bolivia, Brazil), Africa (Niger), India, and Australia are distinctly different from both the Early and Late Carboniferous floras of Gondwana. These floras can be correlated with each other based on macrofloral and palynologic composition, and dated as Late Visean to earliest Serpukhovian through palynologic data from several floras and isotopic data from Australia. The floras are dominated by pteridosperm foliage and characterized by the occurrence of tree-lycopsids, and represent a warm-temperate, frost-free floral belt in Gondwana that reached from 30° to as far as 60° South that existed directly before the onset of the major episode of the Carboniferous glaciation. The plants lived during an interval of very warm climate as indicated by the width and extent of the floral belt, conditions that facilitated the migration of plants into this area from other parts of the globe. The term Paraca floral realm is redefined and extended to include all of these Late Visean-earliest Serpukhovian floras throughout Gondwana.

Floristic migration in South America during the Carboniferous: phytogeographic and biostratigraphic implications

Abstract New data on the Carboniferous flora of northern South America are combined with existing data for Gondwanaland to re-examine the floristic evolution of South America during the Carboniferous. The integration of paleobotanical, palynological, paleomagnetic, paleogeographic and paleoclimatologic data, makes it possible to reconstruct the floristic evolution of South America during the Carboniferous as a dynamic process, that was mainly controlled by the northward movement of the South American plate towards the equator during the Carboniferous. Three Carboniferous floras, the ‘cold’ Archaeosigillaria – Lepidodendropsis – Frenguellia Flora, the temperate Nothorhacopteris Flora and the tropical Euramerican Flora characterize South America. Intra-South American floristic migration is documented by the different age and composition of the Nothorhacopteris Flora. It is of late Early Carboniferous age in northern South America (Bolivia, northeastern Brazil and Peru) whereas it is of Late Carboniferous age in southern South America (Argentina and southern Brazil). The flora was adapted to warm temperate climatic conditions indicating that southern South America moved into this climatic zone during the Late Carboniferous. This migration explains the different ages recorded for the same taxa (e.g., Nothorhacopteris ) in northern and southern South America. Taxonomic differences between the northern and southern Nothorhacopteris Flora reflect Visean–Westphalian evolution.

The Oldest Record of External Foliage Feeding and the Expansion of Insect Folivory on Land

Abstract We describe three specimens from a Late Mississippian (earliest Serpukhovian) pteridosperm (seed fern) Triphyllopteris austrina (Etheridge Jr.) Morris, of probable lyginopterid affinities, which originates from the Sugar Loaf Creek locality of the Sydney Basin, Australia. These specimens provide six examples of folivory assigned to the ichnotaxon Phagophytichnus ekowskii van Amerom 1966. This damage is the earliest example of folivory in the terrestrial fossil record and probably was produced by a “protorthopteroid” or other basal orthopteroid insect, although a more remote possibility is that the culprit was a diplopod. Three important consequences result from this discovery. First, leaves originated 76 million years (m.y.) before the first indication of their folivory. Second, a temporal lag of 6 m.y. is present between the occurrence of T. austrina folivory and the subsequent earliest appearance of herbivorous insect clades in the body-fossil record that could have caused the damage. Third, once the hurdle of folivory was breached, the overwhelming preference of Paleozoic insect folivores was on a taxonomically diverse, paraphyletic spectrum of pteridosperm hosts.

The Triassic taphoflora of the Paraná Basin, southern Brazil: a biostratigraphical approach

Abstract A Triassic taphoflora identified in the Central Region of the State of Rio Grande do Sul, southern Brazil, represents an important biostratigraphical stage in the palaeofloristic succession of the Parana Basin. A megafloristic association composed of compressed leaves, fronds and seeds of a ‘ Dicroidium Flora’ shows a predominance of the Dicroidium genus, with several species and other important taxa like Neocalamites sp., Cladophlebis sp., Tetraptilon aff. heteromerum, Ginkgoites antarctica, Sphenobaiera sp., Podozamites sp., Nilssonia sp., Pteruchus sp. and Carpolithus sp. Taking into account the stratigraphical distribution of different species of the Dicroidium genus, a biostratigraphical framework was established. Considering that the recognition of this ‘ Dicroidium Flora’ was based on limited outcrops belonging to one lithostratiphical level (Santa Maria Formation — Passo das Tropas Facies), it was impossible to established a formal biostratigraphical zonation. Instead, at the present time, an informal floristic interval, named the ‘ Dicroidium odontopteroides Flora’, is proposed (Late Anisian to Late Ladinian, Middle Triassic). An ‘ Araucarioxylon Flora’ composed of secondary woods of the Araucarioxylon type and stems of Rhexoxylon brasiliensis was also identified several km apart. The compressed fossils of the ‘ Dicroidium Flora’ and the petrified stems of the ‘ Araucarioxylon Flora’ could represent different but contemporaneous communities corresponding to fluvial-lacustrine environments.

PALEOBOTANY AND PALYNOLOGY OF THE RIO BONITO FORMATION (LOWER PERMIAN, PARANÁ BASIN, BRAZIL) AT THE QUITÉRIA OUTCROP

Abstract. The sedimentary section at the Quitéria outcrop (Pantano Grande, central portion of Rio Grande do Sul State, Brazil) carries diverse and abundant fossil associations of plants and palynomorphs. This section includes coal deposits of the Early Permian Rio Bonito Formation in the Paraná Basin. This contribution presents a taxonomic re-evaluation on paleobotanical records based on an in-depth revision of available data as well as direct analysis from materials deposited in collections (published and unpublished). A taxonomic list is presented, based on the anlysis of all published data. A stratigraphic framework is offered, showing previous and new records in order to better understand the biostratigraphy of the rocks involved. Accordingt to this re-evaluation, the Quitéria Outcrop carries 14 morphospecies of plant macrofossils —including leaves and seeds of Glossopteridales— constituting a typical coal-forming flora. New palynological data derived from six samples taken in this section reveal diversified and abundant associations, including 29 species of spores, 36 of pollen grains and four taxa related to algae and fungi. Quantitative analysis shows that most samples are closely correlated with the previously known “Lundbladispora-Punctatisporites-Portalites Association”, derived from a hygrophilous environment. The associations are compatible with the Glossopteris-Rhodeopteridium Zone and with the Protohaploxypinus goraiensis Subzone (base of the Vittatina costabilis Zone), related to the Cisuralian (Early Permian). Stratigraphical considerations are based on comparision with neighboring sections and on the regional erosional surface recognized in this outcrop.

Global biostratigraphic comparison and correlation of an early Cisuralian palynoflora from Bolivia

This paper presents new data about Early Permian (Cisuralian) strata, palynostratigraphy and absolute dating from the Copacabana Formation in central Bolivia. Recent stratigraphic and palynologic data from marine and transitional rocks at Apillapampa refine the age of Cisuralian palynomorphs in South America. Twelve samples interbedded with five volcanic ashes (processed and productive) yielded 94 palynomorph species arranged in two informal palynoassemblages: the lower assemblage Vittatina costabilis corresponds to one sample near the base of the Copacabana Formation and the upper Lueckisporites virkkiae assemblage occurs in overlying marine and coal-bearing transitional intervals. Ages were also independently refined by a modern review of conodonts, fusulinids, along with those U–Pb radiometric ages (Isotope Dilution Thermal Ionization Mass Spectrometry [ID-TIMS] of zircon-bearing interbedded tuffs). These data suggest that the lower marine member of the Copacabana Formation at this location is Asselian and Sakmarian. Lueckisporites virkkiae is a key species of palynomorph utilised in South American and global Permian biostratigraphic reconstructions. Hence, a thorough global comparison of these palynofloras and correlations is addressed in this contribution, considering first appearances of mainly cosmopolitan diagnostic taxa. Correlations are established with many similar Permian palynofloras, some also constrained with radiometric data, in South America (Brazil, Uruguay and Argentina) and elsewhere.

Inventary of the Sponge Fauna of the cemitério Paleolake, Catalão, Goiás, Brazil

The Cemitério Paleolake, Catalão, Goiás, is a lacustrine deposit that is rich in spicules of continental sponges. These spicules, which are present in three sections (1-3), were analyzed for the taxonomic identification of the species in order to reconstruct the late Quaternary palaeoenvironment. An indigenous assemblage of lentic sponges was found, consisting of Metania spinata (Carter 1881), Dosilia pydanieli Volkmer-Ribeiro (1992), Radiospongilla amazonensis Volkmer-Ribeiro and Maciel (1983), Trochospongilla variabilis Bonetto and Ezcurra de Drago (1973), Corvomeyenia thumi (Traxler 1895), Heterorotula fistula Volkmer-Ribeiro and Motta (1995), plus Corvoheteromeyenia australis (Bonetto and Ezcurra de Drago 1966), which here has its first record in an assemblage formed by biosiliceous deposits. Furthermore, at the base of the sections, spicules of sponges from lotic environments were detected, including Corvospongilla seckti Bonetto and Ezcurra de Drago (1966), Oncosclera navicella (Carter 1881) and Eunapius fragilis (Leidy 1851), which suggests a contribution from flowing water. We identified 25 spongofacies horizons caused by sponge assemblages typical of a lentic environment, dated from at least 39,700 years BP., and currently occurring in lakes typical of the Cerrado Biome.

Permian plants from the Chutani Formation (Titicaca Group, northern Altiplano of Bolivia): II. The morphogenus Glossopteris

Fossil plants belonging to the morphogenera Glossopteris, Pecopteris and Asterotheca were collected from the upper part of the Chutani Formation (Titicaca Group), near the town of San Pablo de Tiquina, on the southeastern shore of Lake Titicaca (northern Altiplano, Bolivia). This paper presents the first description of specimens of the morphogenus Glossopteris from Bolivia. The Bolivian specimens of Glossopteris consist of poorly-preserved impressions, although they present the diagnostic features of this morphogenus. They are fragments of leaves with secondary veins of taeniopterid-type, typical of glossopterids from Late Permian deposits of Gondwana. The only species ofPecopteris confirmed in the first part of this study, i.e. P.dolianitii Rosler and Rohn (see Vieira et al. 2004), was previously reported from the Late Permian beds of the Rio do Rasto and Estrada Nova formations in the Parana Basin (southern Brazil). Therefore, a Late Permian age is proposed for the fossil plant-bearing beds of the Chutani Formation based on the analyzed assemblage. The phytogeographic implications of this new find are briefly analyzed.

Permian plants from the Chutani Formation (Titicaca Group, Northern Altiplano of Bolivia): I. Genera Pecopteris and Asterotheca

Fossil plants belonging to the morphogenera Glossopteris, Pecopteris and Asterotheca were collected from the upper part of the Chutani Formation (Titicaca Group), near the town of San Pablo de Tiquina, on the southeastern shore of Lake Titicaca (northern Altiplano, Bolivia). Here we report the analysis of fern-type foliage found at this location. Three species of pecopterid fronds are identified: Pecopterisdolianitii Rohn and Rosler, P. cf. P. cadeadensis Rohn and Rosler, and P. cf. P. pedrasica Read. All these species are typically found in Permian deposits of the Parana Basin in southern Brazil. Despite the poor preservation of the material, a fertile specimen could be studied and was determined asAsterotheca sp. The paleoenvironmental and paleoecological implications of this new find are briefly analyzed.

Insect herbivory fluctuations through geological time

Arthropods and land plants are the major macroscopic sources of biodiversity on the planet. Knowledge of the organization and specialization of plant-herbivore interactions, such as their roles in food webs is important for understanding the processes for maintaining biodiversity. A limited number of studies have examined herbivory through geological time. The most have analyzed localities from one restricted interval within a geological period, or a time transition such as the Paleocene-Eocene boundary interval. In the present study, we analyzed the frequency of herbivory and density of damage type (DT) from the Middle Devonian to the early Miocene. The data were compiled from literature sources and focused on studies that describe occurrences of leaves with DTs indicating herbivore consumption as a proportion of the total number of leaves analyzed. The data were standardized based on the DT categories in the Damage Type Guide, and the age of each locality was updated based on the most recent geochronological standard and expressed in millions of years. Temperature and geological age were the best descriptors of the variation in herbivory frequency, which tended to increase at higher temperatures. Two models were equivalent to explain DT density: the interaction between CO2 levels and geological age, and O2 levels and geological age had the same predictive power. The density of DT tended to increase with higher content of atmospheric CO2 and O2 compared to modern values. The frequency of herbivory and the density of DTs appear to be influenced by long-term atmospheric variables.