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Schmelzmikrostruktur in Den Inzisiven Alt· Und Neuwel Tlicher Hystricognather Nagetiere

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Schmelzmikrostruktur in Den Inzisiven Alt· Und Neuwel Tlicher Hystricognather Nagetiere SCHMELZMIKROSTRUKTUR IN DEN INZISIVEN ALT· UND NEUWEL TLICHER HYSTRICOGNATHER NAGETIERE von Thomas MARTIN* INHALT Seite Kurzfassung, Abstract, Resume ............. , ................................................ , 5 Einleitung. 7 Technisches ................ , .................................................. , . 8 Untersuchungsmethoden .......................................... ,..................... 8 Anschliffe fur Auflicht- und Raster~Elektronenmikroskopie ............... , . .. 9 Spezielle Vorbereitung für die Raster-Elekronenmikroskopie .... , ................ , . 10 Auflichtmikroskopie . 11 Schmelzbeschreibung und Messungen ..................................................... 11 Abkürzungen und spezielle Begriffe .......................................... ,............ 12 Problemstellung. 15 Bemerkungen zur Systematik ................... , . , ........... , .................... , . 18 Hystricomorphie und Hystricognathie ...... , ............. , .. '. .. .. .. .. .. 19 Gliederung der untersuchten Nager ......... , . 22 Zahnschmelz ................. , ...................... ,., ... ,.............................. 22 Untersuchungsebenen für den Zahnschmelz. , ................ " .............. , ........... ' . 22 Bauelemente des Zahnschmelzes ..... , ............................. , , . 23 Prismen ........... ,., ............ , ............................................ , .. 23 Interprismatische Matrix (!PM) ....................................................... 23 Schmelztypen in den Nagerinzisiven .. , ................... , . " ......................... , . 24 Hunter-Schreger-Bänder (HSB) ........................ " .......... , ............... , . 24 Pauciseriale HSB ' , , ........ , ....... , .................................. , .. , . 25 Neudefmition pauciserialer HSB .................... , . 25 Multiseriale HSB . 26 Neudefinition multiserialer HSB ...... , ............. " ... , ...... , .......... , . 26 Uniseriale HSB . 28 Radialschmelz . 29 Radialschmelz im pauciserialen Schmelzmuster ...................................... 29 Radialschmelz im multiserialen Schmelzmuster ,..................................... 30 "Innerer radialer Schmelz" ..... , ............... ' ..... , .................. ,........ 30 Prismenlose externe Lage (PLEX) .............. , ....... , ............. , . 31 * Institut für Paläontologie der Freien Universität, Malteserstraße 74-100, D-l000 Berlin 46. Schlüssel-Wörter: Schmelzmikrostruktur, pauciserial, multiserial, Hunter-Schreger-Bänder, Inzisiven, Rodentia, Hystricognathi, Caviomorpha, Phiomorpha, Ctenodactyloidea, Ischyromyoidea, Südamerika, Afrika, Deseadense, Paläobiogeographie. Key-words: Enamel microstructure, pauciserial, multiserial, Hunter-Schreger bands, Incisors, Rodentia, Hystricognathi, Caviomorpha, Phiomorpha, Ctenodactyloidea, Ischyromyoidea, South America, Africa, Deseadan, Paleobiogeography. Mots-eles: Microstructure de l'email, pauciserie, multiserie, Bandes d'Hunter-Schreger, Incisives, Rodentia, Hystricognathi, Caviomorpha, Phiomorpha, Ctenodactyloidea, Ischyromyoidea, Amerique du Sud, Afrique, Deseadien, Paleobiogeographie. Palaeovertebrata, Montpellier, Mem. extra.: 1-168, 181 fig., 12 pI. (Re~u le 13 Novembre 1991, accepte le 16 Janvier 1992, publie le 15 Decembre 1992) Schmelzmuster in den Nagerinzisiven , , , ,. , . , , , ...... , ............................. , .. , .. , , 31 Neudefinition des pauciserialen Schmelzmusters ..... , ............................. , .. ,.. 31 Merkmalskatalog für das pauciseriale Schmelzmuster nach der neuen Defmition , .. " ..... , . 32 Neudefmition des multiserialen Schmelzmusters ........... , .. , ... , ..... , .... , ... , .... , . 32 Merkmalskatalog für das multiseriale Schmelzmuster nach der neuen Deflllition ." ... ,.,....... 33 Der Inzisivenschmelz der untersuchten Sciurognatbi ..... , , , ...... , , .. , , . , , . 34 Paramyidae M1LLER & GIDLEY 1918 . 34 Acritoporamys KORTH 1984 ........................ ' . .. .. 36 Franimys WOOD 1962 .............................................................. 36 Leptotolm" MAlTHEW 1910 ......................................................... 37 Reithroparamys MATI1-IEW 1920 ........ , .. , .......................... " ..... , .. , ... , 37 Thisbemys WOOD 1959 ............................................................. 38 Sciuravidae M1LLER & GIDLEY 1918 . .. .. .. .. 39 Knightomys GAZIN 1961 ............................................................ 39 '?Sciuravidae Prolapsus WOOD 1973 ........ , ...... , ............... , ....... ,........... 40 Ischyromyidae ALSTON 1876 . 40 Ischyromys LEIDY 1856 ............................................................. 40 Cylindrodontidae MILLER & GIDLEY 1918 .... ' . .. .. .. 41 DawsonomysGAZIN 1961 .... , ... , ... , ....... , ..... " ....... , .......... ,............ 41 Mysops LEIDY 1871 ................................................................ 41 Ardynomys MATTHEW & GRA>'IGER 1925 .............................................. 43 Protoptychidae WOOD 1937 ............ ' . .. .. .. 43 Protoptychus SCOlT 1895 ........................................................... 43 Cocomyidae DAWSON, LI & Q11984 .......... ..... .... ... .. ..... .... ...... ...... .. ..... 44 Cocomys DAWSON, LI & QI 1984 ..................................................... 44 Chapattimyidae HUSSAIN, BRUIJN & LE1NDERS 1978 ......................................... 45 Chapattimyidae gen, et sp. indet. 45 cf. Birbalomys SAHNI & KHARE 1973 . .. .. .. .. .. .. 46 Baluchimyinae FLYNN, JACOBS & CHEEMA 1986 gen. et sp. indel. .. .. .. .. 46 Ctenodactylidae ZITTEL 1893 . 46 Leptotataromys BOHLIN 1946 ........................................................ 47 Sayimys WOOD 1937 ............................................................... 49 Sardomys BRUJJN & RÜMKE 1974 ....................................... ,............ 49 Pellegrinia GREGORIO 1887 ......................................................... 50 Ctenodoctylus GRAY 1830 ........................................................... 50 Felovia LATASTE 1886 ............................................................. 51 Massoutiera LATASTE 1885 ......................................................... 51 Pedetidae OWEN 1847.. .. .. .. .. .. .. .. 52 Pedetes ILLIGER 1811 .............................................................. 53 Der Inzisivenschmelz der untersuchten Hystricognathi ...................................... ,..... 53 Tsaganomyidae MATmEW & GRANGER 1923 ............................................... 53 Tsagallomys MA TTHEW & GRAN GER 1923 ............................................. 54 Cyc/omylus MAlTHEW & GRANGER 1923 .............................................. 55 BathyergidaeWATERHOUSE 1841......................................................... 55 Bathyergus ILLIGER 1811 ........................................................... 56 Cryptomys GRAY 1864 ............................................................. 58 Georychus ILLIGER 1811 ............................................................ 59 Heliophobius PETERS 1846 .......................................................... 61 Heterocephalus RÜPPELL 1842 ....................................................... 63 Hystricidae BURNElT 1830 . .. .. .. ... .. .. .. .... .. .... .. .... .. .... .. .. .. .. .. 63 Hystrix LINNAEUS 1758 ............................................................ 64 Athen/rus F. CUVIER 1829 .......................................................... 65 Phiomyidae WOOD 1955 ................................................................ 66 Gaudeamus WOOD 1968 ............................................................ 67 Metaphiomys OSBORN 1908 ......................................................... 67 Phiomys OSBORN 1908 ............................................................. 68 Paraphiomys ANDREWS 1914 ........................................................ 68 Diamantomyidae SCHAUB 1958.. .. .. .. .. 70 Diamantomys STROMER 1922 ........................................................ 70 Thryonomyidae POCOCK 1922. .. .. ... .. .. .. .. 70 ThryoMmys FITZINGER 1867 ........................................................ 70 2 Petromuridae TULLBERG 1899 .......................................................... 71 Petr01J1US A. S~TH 1831 ...... , ........................ , ........................... 71 Erethizontidae THOMAS 1897 ........................................................... 73 Steiromys AMEGHINO 1887 ......................................................... 73 Coendou LACEPEDE 1799 .......................................................... 74 Erethizon F. CUVIER 1822 .......................................................... 74 Chinchillidae BENNEIT 1833 .................................................. " ........ 77 Scotamys LOOMIS 1914 ............................................................ 77 Perimys A..\lEGHINO 1887 .......................................................... 77 Lagostomopsis KRAGLIEVICH 1926 ....................................... '" ........ 78 Chinchilla BENNEIT 1829 .......................................................... 79 Lagidium MEYEN 1833 ............................................................ 80 Eocardiidae AMEGHINO 1891 ........................................................... 80 Eocardia AMEGHINO 1887 ......................................................... 80 Dinomyidae ALSTON 1876 .............................................................. 81 Eumegamys KRAGLIEVICH 1926 ...................................................
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