Dermeval Aparecido do Carmo

On the Validity of Two Lower Cretaceous Non-marine Ostracode Genera: Biostratigraphic and Paleogeographic Implications

Abstract The taxonomic status of the Lower Cretaceous non-marine ostracode genera Hourcqia Krömmelbein and Pattersoncypris Bate is discussed. From a detailed analysis of the type species of these genera, and several other species attributed to them, it was possible to conclude that both genera are invalid. Hourcqia africana Krömmelbein, the type species of this genus, has an antero-ventral beak, and it is in all other respects identical to Cypridea Bosquet, and therefore should be transferred to this genus. The subspecies originally referred to as Hourcqia africana confluens Krömmellbein and Weber, 1971 is subsumed within Cypridea africana. Secondly, the genus Pattersoncypris, as the result of a study of its type species, P. micropapillosa Bate, is shown to be a junior synonym of Harbinia Tsao. Both, Hourcqia and Pattersoncypris must therefore be suppressed. Cypridea africana (Krömmelbein) occurs in Brazil, Congo, and Gabon in strata deposited during the rift stage, restricted to the late Barremian to early Aptian interval. Harbinia micropapillosa (Bate) occurs in Brazil and Liberia, but it is restricted to the gulf stage, i.e. the late Aptian to early Albian interval. Amended diagnoses for the genus Cypridea and species Cypridea africana and H. micropapillosa are given.

Late Cenozoic sea level changes evidenced by ostracodes in the Pelotas basin, southernmost Brazil

Abstract Ostracodes recovered from sediments in seven onshore boreholes within the Pelotas basin, State of Rio Grande do Sul, indicate several continuous nearshore environments and at least four brief transgressive-regressive cycles are present. This interpretation is based on the distribution throughout upper Neogene and Quaternary sequences of species that characterize one or more biofacies depending on the borehole position in the basin. Bradleya pelotensis, Krithe coimbrai, Henryhowella kempfi and H. rectangulata are considered shelf-upper bathyal species whereas the shelf species are represented by Ambostracon crucicostatum, Argenticytheretta variabilis, A. laevipunctata, Brasilicythere reticulispinosa, Caudites posdiagonalis, Costa riograndensis, Coquimba bertelsae, C. tenuireticulata, Cytheretta punctata, Quadracythere eichlerae and Protocytheretta sp. Species with lagoon-estuarine shelf affinities include Callistocythere litoralensis, C. marginalis and Perissocytheridea kroemmelbeini whereas Cyprideis maxipunctata, C. mostardensis, C. posteroinflata, C. salebrosa and C. sparsopunctata represent a lagoon or estuarine environment, and Cypris cassinensis and Limnocythere sp. are freshwater species. Correlation of the ostracode biozones places the four maximum regressive events in the Late Pliocene and Pleistocene (1250-485 ka, 185 ka and 15 ka), whereas the maximum transgressive events occur in the Late Miocene and Pleistocene (1.6 Ma, 423–400 ka and 120 ka), in a barrier-lagoonal depositional system controlled by glacio-eustatic sea level changes.

Taxonomy, Ontogeny and Paleoecology of Two Species of Harbinia TSAO, 1959 (Crustacea, Ostracoda) from the Santana Formation, Lower Cretaceous, Northeastern Brazil

Abstract The Araripe Basin is the most extensive interior basin in northeastern Brazil, comprising areas of Ceará, Piauí and Pernambuco states. The Santana Formation, attributed to the Aptian–?lower Albian age of the basin, is subdivided into two members, Crato and Romualdo, which bear an abundant fossil record of plant fragments, arthropods and vertebrates, especially 3D-preserved fishes. The present study focuses on the taxonomy, ontogeny and paleoecology of two ostracode species from the Romualdo Member and the top section of the Crato Member (Ipubi layers), Harbinia salitrensis (Krömmelbein and Weber, 1971) emend. and H. alta new species. The ontogenetic series for both species are illustrated, except for the A-8 instar; H. salitrensis is also redescribed. The present work is also the first to produce quantitative information about the paleoecology of the Santana Formation based on ostracode populations. The results obtained from analyses of the population age-structure of both species, in addition to dominance (Simpson) and diversity index (Shannon) values, corroborated previous data on the studied sequence. According to these results, the strata were deposited in a limnic, low-to-moderate energy environment with salinity levels varying from oligohaline to mesohaline. The new data indicate the possibility of these environments also being hypersaline.

Taxonomy of limnic Ostracoda (Crustacea) from the Alagamar Formation, middle–upper Aptian, Potiguar Basin, northeastern Brazil

Abstract Fifteen limnic ostracodes species have been recorded in the Alagamar Formation, Potiguar Basin: Cypridea araripensis Silva, 1978a; Cypridea? sp., Harbinia sinuata (Krömmelbein and Weber, 1971); Harbinia crepata n. sp., Harbinia dimorphica n. sp., Harbinia alta Antonietto et al., 2012; Paracypria? elongata n. sp., Ilyocyprimorpha berthoui (Colin and Dépêche, 1997); Ilyocypris? sp., Brasacypris subovatum n. sp., Candona? sp., Theriosynoecum colini n. sp., T. guzzoi n. sp., T. silvai (Silva, 1978b) diagnosis emended by Do Carmo et al. (2004b); and Darwinula martinsi Silva, 1978c diagnosis emended by Do Carmo et al. (2004b). Nine of these species have also been recorded outside of the Potiguar Basin, either in other Cretaceous basins in Brazil or coeval strata in western Africa. Despite the controversy about dating the local Alagoas Stage and the relatively large range of the Zone Harbinia spp. 201–218, the material studied in this paper belongs to the interval corresponding to the well-defined palynological zone coded as P-270, which is mid-upper Aptian in age.

The effects of the inception of Amazonian transcontinental drainage during the Neogene on the landscape and vegetation of the Solimões Basin, Brazil

ABSTRACT Amazonia covers nearly 50% of Brazil. The history of this biome is marked by many changes in the landscape caused mainly by the Central and Northern Andes uplift. This event has influenced the palaeogeography of the Amazon and therefore its biogeography and possibly biodiversity. Herein we present palynological and lithostratigraphical results from the Solimões Formation in the well 1AS-33-AM. It was drilled in the Solimões Basin, Amazonas State, Brazil, reaching 405 m in depth. We identified 152 palynomorphs, in 32 samples, among them some biostratigraphical markers, such as Crassoretitriletes vanraadshoovenii, Fenestrites spinosus, Cichoreacidites longispinosus, Ladakhipollenites? caribbiensis and Echitricolporites mcneillyi, allowing us to recognise four biozones sensu Lorente (1986): Crassoretitriletes Interval Zone (399.10–276.70 m), Asteraceae Interval Zone (276.70–262.00 m), Psilatricolporites caribbiensis Interval Subzone (239.90–70.00 m) and Echitricolporites-Alnipollenites Interval Subzone (70–32 m). The palynological and lithostratigraphical results indicate two environmental phases. The palynomorph association presents a change marked by the sudden appearance and predominance of Grimsdalea magnaclavata from 239.90 m upwards and a general increase in the number of species. The lithostratigraphy shows from approximately the same depth greater amounts of sandstones towards the top of the well, suggesting a change from a paralic to a fluvial environment of higher energy. The first phase can be associated with the Pebas/Acre depositional systems, wetlands composed by lakes and swamps with seasonal floods that existed from 23 to 7–5 Ma. The second phase indicates a fluvial system that may be interpreted as a record of the modern Amazon transcontinental fluvial system, which was already established in the Pliocene.

Taxonomy of limnic Ostracoda (Crustacea) from the Quiricó Formation, Lower Cretaceous, São Francisco basin, Minas Gerais State, Southeast Brazil

Abstract. The present work presents a detailed taxonomic study on Ostracoda from the Quiricó Formation, Areado Group, São Francisco Basin, Brazil. The samples were collected from three outcrops in the Minas Gerais State: Tereza Farm (João Pinheiro Municipality), and from the banks of the São José and Quiricó creeks (Presidente Olegário Municipality). Sixteen ostracode species were recovered: Harbinia alta, Harbinia aff. H. angulata, Harbinia aff. H. crepata, Harbinia aff. H. salitrensis, Harbinia symmetrica, Brasacypris fulfaroi, Brasacypris ovum, Cypridea conjugata, Cypridea hystrix, Cypridea infima, Cypridea jequiensis, Neuquenocypris (Protoneuquenocypris) antiqua, Penthesilenula martinsi, Penthesilenula pintoi new species, Alicenula longiformis new species, and Timiriasevia sanfranciscanensis new species. With the recovery of well-preserved specimens, it was possible to observe new characteristics in Brasacypris ovum, Cypridea conjugata, C. hystrix, and C. infima, and propose emendments to them. Additionally, three new species are described: Penthesilenula pintoi n. sp., Alicenula longiformis, n. sp., and Timiriasevia sanfranciscanensis n. sp. To date, the genus Timiriasevia had not been recorded in strata from Brazil. Also, Darwinula martinsi is reassigned to the genus Penthesilenula. Several species herein recorded are also found in other Brazilian continental basins, as well as in African and Argentinian basins, contributing to the knowledge of Brazilian Cretaceous continental deposits.

Preface: Ostracoda: biostratigraphy and applied ecology

The series of International Symposia on Ostracoda started in 1963, when ISO1 was organised in the historic Zoological Station of Naples by Dr Harbans Singh Puri. Matzke-Karasz et al. (2007) analysed the content of the 15 first ISO proceedings and grouped the 906 papers published in the various proceeding volumes (in stand-alone books and in journals) into several categories. Biostratigraphy and (palaeo-) ecology have always constituted strong components in this series of proceedings, and this inspired the organisers of the ISO16 to determine biostratigraphy and applied ecology as the main themes of their symposium. The 16th International Symposium on Ostracoda was held in Brasilia, Brazil, between 26 and 30 July 2009. The scientific communities from 25 different countries had representatives among the 107 participants, who brought to the meeting an amount of 102 contributions: 46 oral communications, 52 poster presentations and four keynote lectures given by invited speakers. The present proceedings volume comprises ten papers, a small selection of these contributions, and will serve as a legacy to the memory of this highly successful event. As always, the communication of scientific results is of prime importance, but the personal contacts with distant colleagues often leads to fertilisation of ideas and to successful collaborations. The ISO16 meeting scored on both accounts! Furthermore, by holding an ISO for the first time in South America, we hope to have helped foster ostracodology on this continent. In spite of the emphasis given in the current version of the symposium to biostratigraphy and applied ecology, contributions comprised also other research lines, such as Taxonomy, Morphology, Biogeography, Systematics and Evolution. In terms of geological time, the present proceedings contain six papers on Recent faunas, one on Tertiary, two on Mesozoic and one on Palaeozoic Ostracoda. The papers in this volume are loosely organised to follow this chronological sequence. The volume opens with the paper by Decrouy et al. (this volume), who studied the Sediment Penetration Depth of epiand infaunal ostracods in the Swiss Lake Geneva. The relevance of this paper is clear: ostracods have to moult 8–9 times during their development and each time have to calcify their valves using chemical Guest Editors: D. A. Do Carmo, R. L. Pinto & K. Martens / Ostracoda – Biostratigraphy and Applied Ecology