A new contribution to the moss flora of Baltic and Saxon amber

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    Saxon amber (Eocene, 3757 million years B.P.) consisting of 55

    nologBaltic and Saxon amber is a valuable source for

    fossils from many groups of organisms. It originated

    in oakpine forests in Fennoscandia at the north

    shore of a branch of an ocean during Eocene (57

    37 Ma). The amber is attributed to the resin produc-

    quaternary deposits from NE Germany to the Baltic

    Sea. It is not exactly known how the amber accumu-

    lated in the Oligocene and Miocene in Eastern

    Prussia and Saxony (Schlee, 1990; Weitschat and

    Wichard, 1998). There are two hypotheses for the

    origin of the Baltic amber. According to the first1. Introduction grad, also in Saxony (Bitterfeld) and scattered inspecimens is reported. The specimens belong to extant species such as Trachycystis flagellaris (Sullivant and Lesquereux)

    Lindberg, Trachycystis microphylla (Dozy and Molkenboer) Lindberg, Hypnodontopsis conferta (Goeppert and Berendt) J.-P.

    Frahm, Atrichum cf. rhystophyllum (C. Muller) Paris, Haplocladium angustifolium (Hampe and C. Muller) Brotherus,

    Tristichella glabrescens Iwatsuki, Ctenidium capillifolium (Mitten) Brotherus, Campylium cf. squarrosulum (Bescherelle and

    Cardot) Kanda, not specified species of extant genera such as Aptychella, Campylopus, Campylopodiella, Barbella, Brotherella,

    Brachythecium, Bartramia, Drepanocladus, Echinodium, Rhizogonium, and Symphyodon, but also to species described in form

    genera such as Muscites pilifer J.-P. Frahm, Muscites serratus Goeppert and Berendt and Dicranites subflagellare Caspary and

    Klebs. Several fossil mosses could not be identified but are described here as new as Hypnodonopsis pilifer J.-P. Frahm,

    Eurohypnum revolutum J.-P. Frahm, Hypnum palaeocircinale J.-P. Frahm, Hypnites lanceolatus J.-P. Frahm and Hypnites

    complanatus J.-P. The extant species Hypnodontopsis mexicana (Theriot) Robinson has proved to be synonymous with the

    fossil H. conferta (Goeppert and Berendt) J.-P. Frahm, which has priority. T. glabrescens Iwatsuki and C. squarrosulum

    (Bescherelle and Cardot) Kanda from Japan are reported for the first time from the Baltic amber.

    D 2004 Published by Elsevier B.V.

    Keywords: Mosses; Bryophytes; Baltic amber; Saxon amberSo far, the largest collection of mosses from the Baltic andReceived 3 May 2002; accepted 28 November 2003

    AbstractA new contribution to the moss

    J.-P.

    Botanisches Institut der Rheinischen, Friedrich-Wilhelm-U

    Review of Palaeobotany and Palytion of Pinus succinifera (Conwentz) Schubert. Large

    masses of amber are found in marine deposits from

    the upper Eocene or lower Oligocene near Kalinin-

    0034-6667/$ - see front matter D 2004 Published by Elsevier B.V.

    doi:10.1016/j.revpalbo.2003.11.004

    * Fax: +49-228-733-120.

    E-mail address: frahm@uni-bonn.de (J.-P. Frahm).ora of Baltic and Saxon amber

    hm*

    sitat, Meckenheimer Allee 170, D 53115 Bonn, Germany

    www.elsevier.com/locate/revpalbo

    y 129 (2004) 81101hypothesis, the resin was transported by streams into

    the ocean; however, it is not exactly known how the

    resin got into the streams in such masses. According

    to another hypothesis, the amber forests were

    inundated by a transgression (Schubert, 1961) during

    which the trees were drowned, the resin was washed

    out by tides, transported by ocean current and depos-

  • Amain problem with the identification of mosses in

    amber is that relevant characters are only visible in

    single leaves but not in whole plants, where leaf bases

    with alar cells are not visible or laminal cells cannot be

    studied in transmitting light. Therefore, a large number

    of fossils could not be determined or only tentatively

    assigned. Many of these fossils are, however, found

    repeatedly. Therefore, these specimens are described

    here in part as fossil species in extant genera, not

    regarding that the discovery of sporophytes or better-

    preserved specimens could reveal the identity with

    and consists of 13 leaves that are somewhat com-

    planate. The laminal cells are rounded. All these

    J.-P. Frahm / Review of Palaeobotany and Palynology 129 (2004) 8110182ited in clay sediments. Saxon amber is found in

    deposits from the upper Oligocene or lower Miocene.

    It is controversely discussed whether the Saxon

    amber is just a reworked Baltic amber or of indepen-

    dent origin. An argument for an independent origin is

    that the amber was, according to IR-spectographic

    studies, not produced by P. succinifera but by another

    conifer, Cupressospermum saxonicum Mai.

    Besides the amber produced by Pinus succinifera

    (succinite), an amber with a different chemical com-

    position (glesinite, redamite) is also known which

    shows, that other plant families except for Pinaceae

    and Taxodiaceae were also involved in the produc-

    tion of resin.

    The fossil moss flora of the Baltic amber was only

    poorly known for more than 100 years. There were only

    five publications (Goeppert and Berendt, 1845; Goep-

    pert, 1853; Caspary, 1907; Dixon, 1922; Magdefrau,

    1957) dealing with seven species, which all were

    described in form genera. Since 1994, the author, a

    moss taxonomist, started to study mosses from amber

    (Frahm, 1994, 1996a,b, 1999a,b, 2000a,b, 2001a,b)

    and increased our knowledge of the moss flora of the

    Eocene considerably. In total, 150 species of mosses

    are known from the Tertiary of Europe (Jovet-Ast,

    1967; Miller, 1984; Frahm, 2000b) as compared to

    about 1200 species at present. However, most records

    are from the Pliocene (95 species) and Miocene (49

    species). There are only four species recorded from the

    Oligocene and none from the Palaeocene. All records

    except for one from the Eocene are from the Baltic and

    Saxon amber. They concern 47 species (Frahm, 2001a),

    of which 27 species are extant species and the remain-

    ing were described as fossil species or in form genera.

    The authors studies were predominantly based on

    specimens provided by amateur collectors, who con-

    tributed much to the knowledge of the moss flora of the

    amber forest. By courtesy of Christel and Hans-Werner

    Hoffeins (Hamburg), Carsten Grohn (Glinde), Heinrich

    Grabenhorst (Celle),ManfredKutscher (Sassnitz), Jens

    von Holt (Hamburg), Franziska Witsch (Koln) and

    Prof. Dr. Wichard (Bonn) I received again numerous

    mosses from the Baltic and Saxon amber, which are

    described and illustrated here. The Grabenhorst and

    Kutscher collections consist of the Saxon amber (Bit-

    terfeld), all others from the Baltic amber. The speci-

    mens are kept in the private collections of thecollectors.characters refer to the genus Mnium; however, the

    laminal cells are mamillose, which undoubtedly

    places this specimen in the genus Trachycystis.

    In total, six species (three fossil and three extant)

    are known from the genus Trachycystis. Of the three

    Fig. 1. Trachycystis flagellaris (Grohn 2023), plant.

    Fig. 2. Trachycystis flagellaris (Grohn 2023), leaves.

    Fig. 3. Trachycystis microphylla (Wichard 14).

    Fig. 4. Trachycystis flagellaris and T. microphylla (Wichard 14).

    Fig. 5. Hypnodontopsis conferta (Grohn 2031).extant species. In addition, several specimens are listed

    and described, which cannot be determined and not

    even attributed to a genus. They are nevertheless

    included to show the richness and diversity of the

    Eocene moss flora.

    2. Descriptions

    2.1. Trachycystis flagellaris (Sullivant and Lesquer-

    eux) Lindberg (Grohn 2023, Grabenhorst La 3,

    Wichard 14 p.pte.)

    Grohn 2023 (Figs. 1 and 2) consists of a 7-mm-

    long part of an acrocarpous moss with 14 distant

    leaves. The leaves have a percurrent costa, which is

    serrate at the dorsal side. The leaf margin is bordered

    and shows paired teeth. Grabenhorst La 3 is similarFig. 6. Hypnodontopsis conferta (Grohn 2042).

  • J.-P. Frahm / Review of Palaeobotany and Palynology 129 (2004) 81101 83

  • J.-P. Frahm / Review of Palaeobotany and Palynology 129 (2004) 8110184fossil species, two have been reported from the

    Baltic amber (Frahm, 2000a). A key for all extant

    and fossil species of the genus is given by Frahm

    (2001a). The combination of characters of bordered

    leaves with paired teeth refers to the species Trachy-

    cystis flagellaris (Fig. 4), which is still found in

    Eastern Asia. The flagellate branches typical for this

    species have, however, never been found in fossil

    specimens. The fossil Trachycystis microphylla is

    similar with regard to the leaf shape but has no

    leaf-border.

    Trachycystis szaferi Szafran, described as fossil

    species from the Miocene of Poland (Szafran, 1958),

    shall be differentiated by the other species of the genus

    by a costa toothed at the dorsal side. This character also

    concerns, however, Trachycystis flagellaris (Noguchi,

    19871994), and also matches the specimen La 3.

    Therefore, the fossil T. szaferi is probably synonymous

    with the extant T. flagellaris.

    Trachycystis flagellaris was so far recorded once

    from the Baltic amber (Caspary, 1907 as Muscites

    hauchecornei; Frahm, 1994) and exists stillas all

    extant species of this genusin East Asia (Koponen,

    1981).

    2.2. Trachycystis microphylla (Ddozy and Molken-

    boer) Lindberg (Hoffeins 1161.3, Wichard 14 p.pte.)

    Hoffeins 1161.3 consists