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The type specimens of the Characiformes (Teleostei: Ostariophysi) of the Museum of Natural History of Berlin are listed, investigated and the current status discussed. Each taxon is fi gured with its historical original picture, a lateral view and an xray foto. Herein, first the African taxa (families Hepsetidae, Alestidae, Citharinidae and Distichodontidae) are described after a short historical overview about the development of the collection. There are type specimens of 23 taxa of Characiformes from Africa (represented by 6 holo-, 12 syn- And 4 paralectotypes). 17 taxa are valid and 6 are synonyms of other species. In a second part of this publication the type specimens of South-American Characiformes (other than Characidae) and in a third part the Characidae sensu stricto will be studied and discussed.

Hemigrammus fi lamentosus spec. nov. from the rio Araguaya basin is described. There are a typical and a pathological form of the species. The species is closely related with H. taphorni Benine & Lopez, 2007. Typically are (1) the sexualdimorphism and sexualdichromatism, (2) the development of a humeral spot (no humeral spot in H. filamentosus spec. nov. vs. a humeral spot in H. taphorni), (3) the development of a caudal spot (a longitudinal band in the caudal region of the body and no caudal spot in H. filamentosus spec. nov. vs. a caudal spot in H. taphorni), (4) the number of lateral scales (32 to 35 in H. filamentosus spec. nov. vs. 30 to 32 in H. taphorni).

Kunzmann L.,Senckenberg Naturhistorische Sammlungen Dresden
Review of Palaeobotany and Palynology | Year: 2010

Two conifer species from the Upper Turonian of the Saxonian and North Bohemian parts of the Bohemian Cretaceous Basin are redescribed using the type specimens and additional material from the type horizon. In both cases characters of the gross-morphology of foliage shoots and leaf epidermal cell structure observed by LM and SEM are studied. Geinitzia reichenbachii is characterized by uniform falcate leaves that spread abruptly from the axis. They are 4-sided in cross section and have slightly decurrent leaf bases and a single central resin canal. The amphistomatic leaves show adaxially two properly developed stomatal bands with densely arranged stomata and abaxially two stomatal bands repeatedly interrupted. The apertures of the usually incomplete amphicyclic stomatal apparati are randomly orientated relative to the long leaf axis, but oblique and transversal orientation prevails. G. reichenbachii is typified by a neotype and an emended diagnosis is given. Based on detailed comparison to Geinitzia formosa from the Santonian of Quedlinburg, Germany, G. reichenbachii is assigned to Geinitzia Endlicher, 1847 which is considered a natural genus of extinct conifers and type of the Geinitziaceae. This application becomes legitimate because the conservation of the name Geinitzia has been proposed recently by Zijlstra et al. (2010). Sedites rabenhorstii is only known from two small specimens representing ultimate shoots. It is proved that it is a fossil conifer completely distinct from G. reichenbachii. S. rabenhorstii shows epidermal cell characters that have been hitherto described from the genus Glenrosa, a putative Cheirolepidiaceae. S. rabenhorstii differs from Glenrosa in leaf phyllotaxis. The leaves are arranged in four rows, probably in opposite pairs in decussate phyllotaxis. The free leaf part is spreading, straight, triangular in cross section and has an obtuse apex. The leaf base is decurrent. The leaves are amphistomatic with stomata deeply sunken in communal stomatal chambers containing finger-like processes or trichome papillae across the opening. In conclusion, Sedites is maintained as a morpho-genus for fossil conifers and an emended generic diagnosis is given. © 2009 Elsevier B.V. All rights reserved.

Stefen C.,Senckenberg Naturhistorische Sammlungen Dresden
Palaeontologia Electronica | Year: 2010

A morphologic and morphometric study of teeth of some beavers of the group of Palaeocastorinae is presented in order to demonstrate that statistic analyses of tooth parameters could contribute to a better understanding of this group of beavers. The focus was laid on larger samples of Capacikala gradatus, Palaeocastor nebrascensis and "Capatanka" cankpeopi. Additionally, some cranial measurements are briefly considered. Overall morphology of the teeth is very similar in the three genera and can hardly be used to differentiate the considered taxa. Except for hypo- and mesostriae, striae in general are rare in the available material. Whether their rarity is due to how few unworn or little worn teeth are available, or due to the lack of these structures is unclear. Striae thus cannot be considered of taxonomic value in this group. Likewiese, neither the presence of anterior or posterior fossettes, nor their shape and orientation are taxonomically diagnostic. The discriminant analysis of wear-independent residuals showed some separation of Capacikala gradatus,"Capatanka" cankpeopi and Palaeocastor nebrascensis with reasonable sized samples, but not all statistically significantly. The separation of all studied taxa on the basis of the wear-independent residuals of teeth showed some power to separate groups, but here the influence of the differences in sample seizes might be too strong to make clear statements. Also the comparison of tooth row length did not give a clear size separation between all taxa. Size data on skulls are limited and may not represent the real variation. The data of tooth morphometry indicate similarities between C. cankpeopi and C. magnus thus their taxonomic status should be reviewed. Also the differentiation between Capacikala parvus, Capacikala gradatus and Capatanka minor should be reviewed as well as the species assignments in Palaeocastor. Material assigned to Palaeocastor sp. could be separated into three size forms. P. fossor is clearly separated. © Society for Vertebrate Paleontology March 2010.

Vegliante F.,Senckenberg Naturhistorische Sammlungen Dresden | Hasenfuss I.,Friedrich - Alexander - University, Erlangen - Nuremberg
Annual Review of Entomology | Year: 2012

The morphology of 21 exocrine glands and 13 supposedly exocrine structures recorded for lepidopteran larvae is reviewed. The epitracheal glands, for which a double role (exocrine and endocrine) has been demonstrated, are examined as well. Function is well known for at least 8 glands but completely unknown for 6 glands, for 10 putative glandular structures, and for the exocrine component of the epitracheal glands. Functional studies on the remaining structures are insufficient; in some cases (mandibular gland and adenosma) homologous glands may play a different role depending on the species, and only a few taxa have been examined. The secretions of 13 glandular types have been analyzed chemically. The histology of 11 glands is known at the ultrastructural level, whereas that of 6 glands and 7 putative glandular structures is completely unknown. Comparative anatomical studies of the osmeterium, adenosma, and Verson's glands may yield useful information for phylogenetic reconstructions. © 2012 by Annual Reviews. All rights reserved.

Stefen C.,Senckenberg Naturhistorische Sammlungen Dresden
Vertebrate Zoology | Year: 2011

The hair cuticula structure of guard hairs of Laonastes aenigmamus is briefl y described. On average the hairs are 17.13 mm long and 42.63 μm wide below the shield. The cuticle scales show smooth free edges and are crenate only at the tip of the hairs. Some parameters including height, width and area of scale are measured.

The species Hyphessobrycon bentosi DURBIN in EIGENMANN, 1908, Hyph.jackrbertsi spec. nov., Hyph. paepkei spec, nov., Hyph. sweglesi (GÉRY, 1961) and Hyphessobrycon dorsalis spec. nov. are described after a short historical introduction. Hyph. bentosi and Hyph. "robertsi" are treated as valid species contrary to WEITZMAN & PALMER (1997 ff) and Hyph. "robertsi" is scientifically described for the first time as Hyph. jackrobertsi spec. nov. The name Hyph. "robertsi" is broadly distributed in the literature but no valid description was found. Hyphessobrycon bentosi from the surroundings of Obidos (type-locality) is characterized by its (1) relatively low body. The body depth is 2.85 (2.67 to 3.17) times in SL. (2) Maxillary bone with three to eight (to ten; x̄=5.25) conical or tricuspid teeth. (3) Anal-fin with 23 to 26 branched fin rays (x̄=24.71). (4) 30 to 32 longitudinal scales (x̄=31.54). (5) 5/1/4 transversal scales before the dorsal-fin. (6) The fin rays of the dorsal-fin reach not to the adipose-fin in adults. (7) An sexual dimorphism in the dorsal- and anal-fin as in Hyph. jackrobertsi spec. nov. and Hyph. paepkei spec. nov. is not developed. (8) The basic coloration of the body is plain olive brown and not so intensive red as in Hyph. jackrobertsi spec. nov. Hyph. jackrobertsi spec. nov. from the rio Pastaza basin of Peru is characterized by (1) a relatively high body (body depth 2.48 (2.31 to 2.73) time in SL) and (2) a longer anal- and dorsal-fin rays. There are intersects between Hyph. jackrobertsi spec. nov. and Hyph. bentosi in the body depth in juvenile specimens, adults are well differentiated. Hyph. jackrobertsi spec. nov. is similar to Hyph. bentosi in the number of maxillary teeth (five to nine conical or tricuspid teeth (x̄=6.95)). Hyphessobrycon paepkei spec. nov. from the rio Demini basin of Brazil if differentiated by all known members of the rosy-tetra-group (except Hyph. melanopterus (EIGENMANN, 1915)) by its (1) higher number of maxillary teeth (14 to 21 conical to tricuspid teeth (x̄= 15.98) and (2) the shape of anal-fin. There are two color forms of Hyph. sweglesi (GÉRY, 1961), which are conspecific, similar to Hyph roseus (GÉRY, 1960). Hyphessobrycon dorsalis spec. nov. from the rio Caures basin of Brazil is characterized by the following combination of features (1) a relatively elongated body (body depth 3,59 (3.41 to 3.76) times in SL), (2) basis of caudal-fin with two large scales, (3) praemaxillary bone with two rows of teeth (two tricuspid teeth, seldom one tricuspid tooth in the external row and six tricuspid teeth in the internal row), (4) maxillary bone with three to four tricuspid teeth, (5) anal-fin with iii 21 to 23 rays, (6) scales: 4-5/(5-7)31-32/3, (7) a distinctly developed pseudotympanum, (8) a black spot in the dorsal-fin and (9) no humeral spot. © Senckenberg Gesellschaft für Naturforschung, 2014.

Linnemann U.,Senckenberg Naturhistorische Sammlungen Dresden | Gerdes A.,Goethe University Frankfurt | Hofmann M.,Senckenberg Naturhistorische Sammlungen Dresden | Marko L.,Goethe University Frankfurt
Precambrian Research | Year: 2014

The Cadomian Orogen in the NE Bohemian and the northern Armorican Massifs shows a distinct orogenic zoning from recent NW to SE consisting of (i) an outboard sitting continental crustal unit comprising Neoproterozoic rocks associated with c. 2.0Ga old Icartian Basement, (ii) a magmatic arc and a back-arc basin, (iii) a foreland or retro-arc basin, and (iv) the passive margin of the back-arc basin. New U-Pb zircon ages of detrital zircon of Neoproterozoic to Fortunian siliciclastics from the Schwarzburg Antiform in the Saxo-Thuringian Zone (NE Bohemian Massif) identify the West African Craton as the hinterland for the Cadomian Orogen as demonstrated by zircon populations dated at 1.8-2.2, 2.5-2.7, 3.0-3.1, and 3.4-3.5Ga. The dominant zircon population (c. 50-70% in each sample) is derived from a Cadomian magmatic arc in a time slice of c. 570-750Ma. The magmatic activity of the Cadomian arc stopped at c. 570Ma. Closure of the back-arc basin by arc-continent collision occurred between c. 570 and 542Ma under the formation of a foreland (retro-arc) basin. A short-living remnant basin existed between c.542 and 540Ma. Granitoid plutonism at 539-540Ma documents the final pulse of the Cadomian Orogeny. Hf isotope compositions, calculated e{open}Hfi values and TDM model ages for detrital and magmatic zircon show that during the c. 180Ma long Cadomian magmatic arc activity juvenile arc magmas were contaminated by recycling of Eburnian and Archaean crust. Mixing with an evolved continental crust is always present. The inferred geotectonic setting is a continental magmatic arc during the Neoproterozoic developed on a stretched Archaean and Palaeoproterozoic (Eburnian) crust. In the West African crustal evolution it can be demonstrated that during Eburnian orogenic processes (c. 1.8-2.2Ga) in most cases a 2.5-3.4Ga old basement became reworked. Archaean 2.5-2.9Ga magmas remelted a 3.0-3.4.Ga crust. Zircon grains with an age of 3.0-3.1 and 3.4Ga are derived from juvenile magmas. Two zircon grains dated at 2779±22 and 3542±28Ma imply reworking of pre-existing Eoarchean to Hadean crust and show TDM model ages of 3.98 and 4.29Ga, respectively. © 2013 Elsevier B.V.

Richardt N.,Senckenberg Naturhistorische Sammlungen Dresden | Wilmsen M.,Senckenberg Naturhistorische Sammlungen Dresden
Newsletters on Stratigraphy | Year: 2012

Two cores from two localities (Anröchte and Werl drill-holes) situated at the southeastern margin of the Münsterland Cretaceous Basin (MCB; NW Germany) have been logged bed-by-bed and sampled at 0.5 m-intervals for chemostratigraphic investigation. Detailed studies provide new data for establishing a standard section through the lower Upper Cretaceous (Lower Cenomanian-Middle Coniacian) of the "Haarstrang" area. The Upper Cretaceous succession has a thickness of about 180 m in total - including an overlap of 7.00-8.70 m in the Middle Turonian interval - and overlies strata of Carboniferous age. The Anröchte core contains sediments of the Essen Greensand, Baddeckenstedt and Brochterbeck formations as well as the Büren and the lower part of the Oerlinghausen formations (Lower Cenomanian-lower Middle Turonian), while the Werl core penetrates the middle and upper part of the Oerlinghausen Formation, the Salder Formation developed in Soest Greensand facies, the Erwitte and lower Emscher formations (lower Middle Turonian-Middle Coniacian). The rather proximal depositional position of the cores has resulted in condensed lithofacies and relatively low thicknesses, especially for the Cenomanian. Moreover, new results require minor revisions of the established lithostratigraphic scheme. Based on carbon stable-isotope data, an overlap of the two core sections has been identified. All isotope events reported from contemporaneous successions (e. g., Baddeckenstedt, Halle/Westfalen, Oerlinghausen, Salzgitter-Salder and Dover) have been recognized and correlated inter-regionally. Through the Cenomanian, these are - in ascending order - the vaguely placed LCE I-III, the provisionally located Crippsi and Virgatus Beds events, the MCE I (only MCE Ib peak is present), the MCE sensu Ernst et al. as well as the P/B Break, MCE II, Jukes-Browne, Amphidonte Bed and Monument isotope events. The positive excursions of δ13C values during the Cenomanian Oceanic Anoxic Event MCE I and OAE 2/CTBE is also well represented. Furthermore, the Turonian interval shows the Holywell, Lulworth, Round Down, low-woollgari, Glynde, Pewsey, Lower and Upper Southerham, Caburn, Bridgewick, Hitch Wood and Navigation events. In the Coniacian, the Beeding, Light Point and East Cliff events are developed. Sequence boundaries of major significance are observed as omission and/or erosion surfaces followed by conspicuous, lithoclastic marl layers and are often characterized by abrupt facies changes. Major unconformities (SB Ce 1-5, SB Tu 1-5, SB Co 1) are related to eustatic 3rd-order sea-level falls and are well known from many Cretaceous localities, particularly in Europe. © 2012 Gebrüder Borntraeger, Stuttgart, Germany.

Wilmsen M.,Senckenberg Naturhistorische Sammlungen Dresden
Acta Palaeontologica Polonica | Year: 2012

Palaeontological events, documented by widespread beds or thin intervals of strata with either unusual ("exotic") or acmes of common faunal elements are a characteristic feature of Upper Cretaceous epicontinental shelf sediments in NW Europe. Their importance in stratigraphic calibration has early been recognized and these "bioevents" are widely used as correlation tools. Furthermore, it appears that there is a genetic link between sequence and event stratigraphy as most of the "classic" bioevents developed during specific intervals of a 3rd-order depositional sequence. Early transgressive bioevents (ETBs) are subdivided into two subtypes, i.e., the lag and migration subtype. The lag subtype corresponds to the transgressive surface and develops in response to winnowing and relative enrichment of robust biogenic hardparts. Taphonomic alteration and time-averaging are important features. The migration subtype is related to the disappearance of physical or ecological barriers that triggered faunal migrations. Despite their onlapping character, most ETBs are quasi-isochronous, and their preservation potential is usually high. Thus, they are very useful stratigraphic markers. Maximum flooding bioevents (MFBs) represent autochthonous biogenic concentrations with relatively low shell densities. They are related to habitat stability and ecospace expansion, and develop by population blooms of taxa well adapted to the special maximum flooding conditions of the wide epicontinental shelf of NW Europe (e.g., low food availability). Cenomanian MFBs of NW Europe are not time-averaged and may comprise stratigraphically more expanded intervals with gradational lower and upper boundaries. Their often wide palaeogeographic extent associated with very high chances of preservation results in an excellent inter-basinal correlation potential. Late highstand bioevents (LHBs) are local to regional shell concentrations deposited as a result of increasing winnowing of fines and reworking by storms, currents and waves during late highstands. LHBs usually consist of paucior even monospecific skeletal concentrations with a high degree of fragmentation. Simple shell beds related to a single (storm) event, and composite (multiple-event) shell beds are recognized. LHBs share some features of ETBs, but lack of time-averaging, are laterally restricted and have low preservation potential. Thus, their importance in interbasinal correlation is poor. The time scales of Cenomanian bioevents range through several orders of magnitude (hours-days in LHB storm event concentrations to ∼100 kyr in MFBs). In terms of position within sequences, the three bioevent types correspond to shell concentrations recognized in Mesozoic-Cenozoic formations around the world. Shell beds with similar positions within cycles as well as comparable sedimentologic and taphonomic characteristics have also been described from high-frequency sequences and parasequences, suggesting that the formational processes of shell beds operate in base-level controlled sedimentary cycles of different hierarchies (i.e., 3rd-up to 7 th-order). Copyright © 2012.

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