GEOLOGICA CARPATHICA, 52, 5, BRATISLAVA, OCTOBER 2001
301 — 318
NON-MARINE CALCAREOUS ALGAE OF UPPER JURASSIC TO
LOWER CRETACEOUS SEQUENCES FROM THE
WESERBERGLAND (NORTHWEST GERMANY)
and DETLEV K. RICHTER
This paper is dedicated to the Dr. Hans Füchtbauer, Professor Emeritus of the Institute of Geology, Ruhr University Bochum
(Germany) with the occasion of 80
University of Bucharest, Faculty of Geology and Geophysics, Laboratory of Paleontology, Bd. N. Balcescu 1, 70111 Bucharest, Romania
Ruhr-University Bochum, Institute of Geology, Mineralogy and Geophysics, Universitätsstraße 150, 44780 Bochum, Germany
(Manuscript received January 11, 2001; accepted in revised form June 13, 2001)
Abstract: The Upper Jurassic/Lower Cretaceous brackish carbonate sequences of the Weserbergland area (NW Ger-
many) contain numerous calcareous algae and cyanobacteria closely associated with layers dominated by serpulids and
ooids. Algae are an essential tool for the interpretation of brackish environments. Several new taxa of Chlorophyta
(Pseudopenicillus weseri n.sp., Springerella bifurcata n.gen. n.sp., S. fuchtbaueri n.sp., Brachydactylus reisi n.sp.) and
one new species of Cyanobacteria (Ponsella freyteti n.sp.) are described.
Key words: Germany, Jurassic—Cretaceous, non-marine, calcified, cyanobacteria, algae.
Little is known about fossil fresh or brackish water algae (e.g.
Toomey & Nitecki 1985). Furthermore, specific data about
chlorophytes and cyanobacteria of the serpulid containing se-
ries of Upper Jurassic to Lower Cretaceous age in NW Germa-
ny do not exist. This seems surprising because the series often
contain deposits of non-marine environments within the wide-
spread area of the so-called Portland Trough (Fig. 1).
Recently, Freytet (1997, 1998, 2000) and Freytet et al.
(1999) reviewed the record of non-marine algae from the Per-
mian to the present-day – some of them found in travertine
and tufa – establishing 16 new genera and 56 new species.
The study of the fossil non-marine algae has long been ne-
glected, altough Reis (1923) published and described new taxa
from the Miocene of Rheinpfalz (Donnerberg Sheet) as fol-
lows: Ternithrix compressa – a girvanelloid cyanobacterium
(Oscillatoriaceae), Dimorphostroma palatinum, D. diffusum
(Rivulariaceae), Chlorellopsis coloniata, Microchorton clav-
iger, Dendractis brevis, D. compacta, Brachydactylus radia-
lis, Cladophorites incrustans and C. dubius (Chlorophyta).
More recently, Chlorellopsis coloniata was also found in the
Miocene of the northern Rhine Valley by Stapf (1988) and in
the Ries Crater by Arp (1995). Cladophorites incrustata was
decribed from the Miocene of the Ries Crater by Riding
(1979) and Arp (1995).
Uppermost Jurassic to Lower Cretaceous sequences con-
taining serpulids are typical of the final carbonate facies of the
E-W striking Portland Trough in northwestern Germany
(Fig. 1). This facies characterizes the more or less marine parts
of the so-called Malm group (Fig. 2) until the non-marine
Wealden facies extends with the Bückeberg Formation far
over the coastline of the Upper Jurassic basin (Gramann et
al. 1997). Compilations (Gramann et al. 1997) emphasize that
the < 100 m thick Serpulit Formation correlates with the
youngest bed (OM 6) of the Malm group. Biostratigraphically,
the Serpulit Formation is assigned to ostracod zones 22/23 and
charophyte zones 7/8 (Berriasian of Gramann et al. 1997).
The “Serpulit” sensu stricto corresponds with the Upper Ser-
pulid Limestone of Casey et al. (1975) and Schonfeld (1979).
The Münder Marl ranges from Tithonian (OM 3 and OM 4) to
Lower Berriasian (OM 5) (Gramann et al. 1997).
The first description of serpulid limestones from the south-
ern coast of the Portland Trough (Fig. 1) was published by
Blumenbach (1803). Hoyer (1965) interprets these as a near-
coastal facies with serpulid biostromes, while Huckriede
(1967) explains the same sedimentary succession by transpor-
tation and sedimentation of tubes of the phytal living Serpula
coacervata. According to the Huckriede (1967), serpulid fa-
cies of Hannover reflects meio- to pleiomesohaline conditions
of brackish water (3—18 ‰ salinity) and only the marly inter-
calations were oligohaline (0.5—3 ‰). For the Upper Serpulid
Limestone in the area south of Hannover, Schonfeld (1979)
supposes a predominant alternation of limnic (partly subaerial
with desiccation) and brackish/marine (10—18 ‰) conditions,
whereas some local celestine intercalations probably indicate
episodically higher salinity environments. Based upon well-
known anhydrite and halite layers in the deepest parts of the
sedimentary basin (Brand 1954), Gramann et al. (1997) as-
sume a salinity stratification during sedimentation of the ser-
pulid (OM 6) sensu Schott (1951) and Jordan (1971). Due to
increasing humidity of the climate the limnic to terrestrial
Wealden facies finally overlaps the dominantly carbonate ma-
rine facies with variable salinity within the Portland Trough of
The paleoecology of serpulid outcrops in northwestern Ger-
many are described by Jahnke & Ritzkowski (1980), focusing
on the uppermost Jurassic deposits, and by Ten Hove & Van
Den Hurk (1993) dealing with lowermost Cretaceous.
The localities of our study represent the serpula-dominated
facies of the southern coastal zone of the Portland Trough situ-
ated southwest/south to Hannover (Fig. 1). The bulk of the
samples was taken from three disused quarries in the Deister
Mountains north of Springe:
Locality 1 – Lower Serpulid Limestone (samples Bre 1—2)
overlain by marls and fine-grained siliciclastic sediments con-
taining thin and partly nodular limestone intercalations (sam-
ple A3); map and Gauss-Krüger coordinates – MTB 3723
Springe, H 5789800, R 3538160; the locality corresponds to
Loc. 142 of Hoyer (1965), Loc. 1 of Schönfeld (1979) and
Loc. 132 of the geological tourist map of the rural district of
Locality 2 – Upper Serpulid Limestone (samples 835 and
38/1—5); MTB 3723 Springe, H 5790210, R 3538480; the lo-
cality corresponds to Loc. 143 of Hoyer (1965) and Loc. 38 of
Locality 3 – Upper Serpulid Limestone (samples 37/1—5);
MTB 3723 Springe, H 5790370, R 3538070; the locality cor-
responds to Loc. 141 of Hoyer (1965) and Loc. 37 of Schön-
A minor part of the samples was taken from an active quarry
(Schütte Company) situated ESE of Thüste village (about 20
km SSE of Springe):
Locality 4 – Oolitic Serpulid Limestone (samples F1—3);
MTB 3923 Salzhemmendorf, H 5765650, R 3545100; the lo-
cality corresponds to Loc. 21 of Herrmann (1968 – calcare-
Fig. 1. Sketch map showing the position of the localities 1—4. A – Paleogeographic distribution of the Portland Trough in northwestern
Germany according to Betz et al. (1987). B – Geological map for the eastern part of the Deister area, north of Springe (Geologische
Wanderkarte 1:100,000-Landkreis Hannover, 1977).
NON-MARINE CALCAREOUS ALGAE OF JURASSIC TO CRETACEOUS SEQUENCES 303
Fig. 3. Schematic facies pattern for the Upper Jurassic to Lower Cretaceous coastal area, south of Hannover following the models of Logan
et al. (1970) and Jahnke & Ritzkowski (1980) – with supplements. The positions of the localities 1—4 correspond to the horizontal and verti-
cal facies pattern but not to the stratigraphical position.
Fig. 2. Stratigraphic column for the Jurassic to Lower Cretaceous
in the investigated area (Jordan 1979; Gramann et al. 1997).
ous facies of the Münder Marl) and Loc. 57 of Jordan (1979 –
Upper Jurassic “Serpulit”). According to Jahnke & Ritzkowski
(1980) all sampled limestones can be assigned to the middle
part of the Münder Marl (OM 4) below a stromatolitic horizon
and, consequently, they are assumed to be stratigraphically
lower than the Serpulit Formation. Gramann et al. (1997)
place the serpulid limestones from the Hils Syncline near
Thüste in ostracod zone 19, which corresponds to lithostrati-
graphic position OM 4.
Microfacies and diagenesis
In order to understand microfacies and diagenesis of the
samples some information is necessary concerning the envi-
ronmental and stratigraphic situation at the southern coast of
the Portland Trough (Fig. 3). We assume a restricted sea with
tidal effects influenced by deltaic sedimentation. Normally,
the supratidal flats were followed in a seaward direction by
stromatolitic to oncolitic facies, mud facies (wacke/mud-
stones), bar facies (grain/packstones) and mud facies wacke/
mudstones). Furthermore, we assume channels as a connec-
tion between river and basin areas (Fig. 3). This sedimento-
logical scenario moves with transgression and regression cor-
responding to the rule of Walther (see Jahnke & Ritzkowski
1980). This simple paleogeographic situation was complicat-
ed by changing salinities caused by deltaic influence and
The Lower Serpulid Limestone at Loc. 1 and the limestone
facies of the Münder Marl at Loc. 4 consist predominantly of
grain/packstones rich in bioclasts and/or ooids (bar facies in
Fig. 3). In some cases elongated clasts of serpulids, bivalves
and algae trace plane and cross bedding. At the top the Ser-
pulid Limestone of Loc. 1 a remarkable velocity of flow is im-
pressively indicated by current ripples. This typical feature for
near coastal sedimentary environments is in good agreement
with the paleogeographic position of the investigated localities
at the margin of the Portland Trough (see Fig. 1).
More or less broken tubes of serpulids (Serpula coacervata
according to Schönfeld 1979 and Ten Hove & Van Den Hurk
1993) are the main bioclasts. Often, these tubes show tele-
scope-like interlocking (Fig. 8.3) so that using only a band-
lens they can be misinterpreted as ooids. In addition, there are
thalli and fragments of green algae and cyanobacteria (see pa-
leoalgological description) as well as different types of shells.
Monolayered prismatic shells and doublelayered shells – pri-
marily calcitic as well as formerly aragonitic layers – can be
assigned to bivalves, whereas shells which are completely
composed of calcitic fibres or formerly aragonitic shells can-
not be clearly identified. Particularly the samples from Loc. 4
(Thüste) contain gastropods and ostracods in addition to bi-
valves. Foraminifers and ostracods in the samples from Loc. 4
seem to be reworked from older beds (see paleogeographic
situation in Fig. 1) because of their distinctive diagenetic
composition – e.g. Fe-calcites in skeletons and intraparticle
pores which differ from those of the surrounding particles
Ooids are common in all studied microfacies types from Ti-
thonian to Berriasian and in some layers they can be regarded
as rockforming (Fig. 8.4). This is especially the case at Loc. 2
and Loc. 4 as well as in the marly beds between the Lower and
Upper Serpulid Limestones (Loc. 1) according to Schönfeld
Aside from normally structured ooids with spherical nucleus
and cortex (Fig. 8.4), more complex ooids (Fig. 8.5) and hiatus
ooids (broken and regenerated ooids; Fig. 8.4) occur (see
Richter 1983). Within the beds of Loc. 4 with its relatively
high proportion of formerly aragonitic bioclasts, “eggshell di-
agenesis” (Wilkinson & Landing 1978 – dissolution of ara-
gonitic nuclei before compaction of the sequence) can be ob-
served in some cases (Fig. 8.6). Generally, all ooids of the
studied localities have a radialcalcitic structure which is typi-
cal for marine ooids in the “calcite time” from Lower Jurassic
to Upper Cretaceous sensu Sandberg (1983). Fe-calcitic ooid
cortices point to a primary composition of radially structured
Mg-calcite (according to Richter & Füchtbauer 1978; Richter
1984). However, an exact value of the primary Mg portion
cannot be determined. But, taking into account the abundant
non-marine green algae and cyanobacteria, and the (brackish)/
marine serpulids, brackish conditions with oscillating salinity
(fine cathodoluminescence zonation in the ooid cortices indi-
Fig. 4. Distribution of algae and the paleocommunities during the Upper Jurassic and Lower Cretaceous in Weserbergland, NW Germany.
NON-MARINE CALCAREOUS ALGAE OF JURASSIC TO CRETACEOUS SEQUENCES 305
cating a primary geochemical fluctuation) seems likely. This
interpretation is further supported by the distribution of radial-
calcitic ooids in the Neogene/Quaternary sequences of the
Isthmus of Corinth (Richter & Neuser 1998) where ooids oc-
cur within a Neogene/Quaternary cyclic sequence of glacial-
eustatic origin – marine conditions with seawater highstands
and lacustrine-brackish conditions with sea-level lowstands
and isolation of seas neighbouring the Mediterranean (in this
case, the Gulf of Corinth). Ooids with aragonitic cortices (re-
placed by secondary isometric calcite) are limited to marine
episodes whereas radial Mg-calcitic cortices (often replaced
by Fe-calcite) occur in lacustrine-brackish periods.
The groundmass of the grain/packstones is predominantly
formed by cement, whereas matrix – a. micritic, b. pelmicrit-
ic (clotted limestone sensu Bathurst 1971, peloidal structure
due to crystallization with participation of bacteria according
to Chafetz 1986) – can be exclusively observed in pack-
stones. The first cement generation consists of calcitic pali-
sades, which can be observed, mostly in intraparticle pores –
especially in serpulids. This was probably an early cement, but
it is impossible to reconstruct the primary Mg content or the
salinity. The normal sequence of cements is formed by isomet-
ric calcite with an ideal succession calcite I, Fe-calcite, calcite
II. The same cement succession can also be observed in disso-
lution pores of formerly aragonitic particles if they were not
previously calcitized in situ (compare Fig. 8.7).
Wacke/mudstones are common especially in the Upper Ser-
pulid Limestone of localities 2 (Fig. 8.2) and 3, and also in the
marly sequences between Lower and Upper Serpulid Lime-
stone at locality 1 and in the upper part of the calcareous facies
of the Münder Marl at locality 4 (mud to stromatolite facies in
Fig. 3). The wacke/mudstones occur as beds and as intraclasts.
With respect to ooids and biogenic components the wacke/
mudstones are similar to the grain/packstones, but the predom-
inantly micritic facies contains a distinctly higher proportion
of green algae and cyanobacteria (see paleoalgological de-
scription). Partly, the wacke/mudstones have a strongly in-
creased proportion of intraclasts and oncoids. At locality 3
these oncoids can reach diameters in the range of decimeters
(Fig. 8.1) and in some cases are composed of a complex algal
community. Detrital quartz grains complete the component
spectrum of the wacke/mudstones. Few of these grains show
authigenic rims of quartz.
The groundmass is dominated by a micritic to peloidal,
sometimes microsparitic matrix (according to Füchtbauer &
Richter 1988). Often the calcareous content of the matrix is
more or less substituted by clay and silt, so that the petro-
graphical composition corresponds to marls or marly clays.
Residual spaces of interparticle pores, intraparticle pores (es-
pecially in serpulid tubes) and shrinkage cracks were mostly ce-
mented by calcite. Normally, a sequence of calcite I, Fe-calcite
and calcite II can be observed corresponding to the cementation
sequence in the grain/packstones. Rarely, in some intraparticle
pores (serpulid tubes, completely preserved ostracod shells) an
initial palisade-shaped cement generation may occur.
Figs. 5—6. Springerella bifurcata nov. gen. nov. spec., thallus with
long Y-shaped dichotomously branched tubes and swellings in the
area of branching, also rare swellings between the successive di-
In thin sections of the Upper Serpulid Limestone of locali-
ties 2 and 3 the blocky calcite cement is often pigmented by
opaque material and exhibits internal zones of calcite and Fe-
calcite. The presence of lentil-shaped calcite pseudomorphs
after gypsum in the matrix, showing the same features as the
calcite mentioned above, a pseudomorph origin also seems to
be probable for the blocky calcite areas in the inter- and intra-
particle pores. This blotchy distribution of calcite can be ex-
plained by changes of the redox conditions in the pore fluid
during calcification of gypsum.
Paleoecology of non-marine algae
The communities recorded at the Jurassic-Cretaceous
boundary within the Weserbergland region, NW Germany, in-
cluded marine and non-marine algae, serpulids, bivalves, gas-
tropods, ostracods and coprolites. These occurred in shallow
basins at coast lines with a varied morphology: subtidal, inter-
tidal with limnic pools and supratidal, crossed by tidal or fluvi-
atile channels (Fig. 3).
In an attempt to reconstruct the paleoecological conditions
of this time interval, correlated with the depositional environ-
ments, three characteristic communities can be recorded:
a) Community dominated by Halimedaceae (Pseudopeni-
cillus weseri) confined to the subtidal, marine realm, corre-
sponding to the depositional environment of the Oolitic Ser-
pulid Limestone (locality 4) of the Münder Marl Formation
(= OM 4), Upper Tithonian in age.
The occurrence of broken algal segments, as elongate, paral-
lel bioclasts, indicates that they were transported by “tidal
streams” especially within the channel facies where they accu-
Fig. 7. Reconstruction of a stromatolitic nodule built by various algae and microbes: in the basal part algal-micrite, microbialite, covered by
Chlorellopsis coloniata Reis composed of spherical cells, then Broutinella arvernensis Freytet, mainly represented by monostrata crust, in-
terlayered with Ponsella freyteti nov. spec. and in the upper part, laminated layers with protuberances of Brachydactylus reisi nov. spec. and
NON-MARINE CALCAREOUS ALGAE OF JURASSIC TO CRETACEOUS SEQUENCES 307
Fig. 8. 1: Megaoncoid of the Upper Serpulid Limestone (Lower Berriasian), Loc. 3. Sample courtesy of Hans Füchtbauer. 2: Wackestone
with debris of serpulids and some ostracods (arrows) – Upper Serpulid Limestone (Lower Berriasian), Loc. 2. 3: Grainstone containing
calcitized bivalves, ooids (o) and tubes of serpulids with telescope-like interlocking – Lower Serpulid Limestone (Lower Berriasian), Loc.
1. 4: Oolitic grainstone – normal ooids (no) and hiatus ooids (ho). Münder Marl (OM 4), Loc. 4 (Upper Tithonian). 5: Packstone contain-
ing a complex ooid – Lower Serpulid Limestone (Lower Berriasian), Loc. 1. 6: Ooids with eggshell diagenesis (ed) – Lower Serpulid
Limestone (Lower Berriasian), Loc. 1. 7: In situ calcitized molluscan fragment (see residual structures) – Lower Serpulid Limestone (Low-
er Berriasian), Loc. 1.
Fig. 9. 1—3: Pseudopenicillus weseri n.sp., 1. Holotype, Coll. L.P.B. V, No. 1120, sample F3A, vertical, axial section in cylindrical segments
of thallus; 2—3. Thallus morphology with cylindrical segments separated by constrictions and type of cortical utricle siphons. 4: Pseudopen-
icillus weseri n.sp., Isotype, debris in a broken thallus showing the shape and ramification of the utricle siphons in the cortical area (see ar-
rows). 5—6: Pseudopenicillus weseri n.sp., Isotypes, vertical axial sections; thalli cylindrical with constrictions between segments (see ar-
rows), sometime broken between tubes of serpulids or fixed on one side of the thallus. 7: Pseudopenicillus weseri n.sp., Isotype, broken
thallus, which preserves only one side of the cylindrical segment. 8—9: Oolite with ooids, oncoids, debris of Pseudopenicillus weseri n.sp.,
gastropods, bivalves and serpulids, sample F2. Upper Tithonian, Oolitic Serpulid Limestone (Münder Marl = OM 4), Salzhemmendorf, Wes-
erbergland, NW Germany.
NON-MARINE CALCAREOUS ALGAE OF JURASSIC TO CRETACEOUS SEQUENCES 309
mulated during slow sedimentation, as a function of their
shape, dimensions and weight. They produced bioclastic accu-
mulations as micro-rhythmites.
The marine deposits with normal salinity reached the interi-
or by repeated marine “invasions” along the tidal channels,
generating “micro-rhythmitic” deposits of thallus fragments
(only cortical parts), together with rare serpulid tubes, benthic
foraminifers (Lenticulina, Epistomina, Nautiloculina) and bi-
valve shells (Fig. 4).
Small oncoids, 0.2—0.4 mm in diameter occur rarely and al-
gal pellets were deposited in “quiet” environments, after their
b) Community dominated by Serpula coarcervata, tubes
embedded in micrites (locality 1) (Ten Hove & Van Den Hurk
The matrix is made of pure micrites and biogenic micrites
resembling algal pellets and stromatolites, fine quartz grains
(0.010—0.10 mm) and clasts (clay, marls or micrite).
In addition to serpulid tubes, the community includes shells
and shell fragments of bivalves, ostracods and rare charophyte
gyrogonites, together with coprolites deposited in shallow in-
tertidal, bar and limnic pool areas. In these “ponds” oncoids
formed with dimensions of 2—10 mm.
From a paleoalgological point of view, 4 morphospecies are
identified: Chlorellopsis coloniata Reis, Broutinella arvernen-
sis Freytet, Ponsella freyteti n.sp. and Brachydactylus reisi
n.sp. (Fig. 7).
Two types of stromatolites can be observed: homogenous
and heterogenous sensu Freytet (2000). Both categories are
abundant, reflecting the growth of flat laminae, hemispheres,
small domes and columns, like Broutinella arvernensis.
The microbial encrustation B. arvernensis is initially micrit-
ic, followed by radial sparite palissades type in laminated mi-
cro-build-ups. The microlaminations are interpreted as a result
of bacterial activity with a daily rhythm and a fabric made of
The homogenous stromatolites have nodular-ellipsoidal
shapes, 2.5—3.0 mm in diameter, enclosing gastropod shell
fragments and, in the outer part, microbial crusts of Broutinel-
The heterogenous stromatolites are larger (4.5—10.0 mm in
diameter) and have nodular-ellipsoidal shapes bearing external
protuberances with a vertical growth tendency, initially tempo-
rarily fixed to the substrate, finally generating in place build-
There are oval-ellipsoidal algal nodules with cerebroid ex-
ternal surfaces and diameter of 3.0—4.0 mm. They include a
core of Chlorellopsis coloniata, covered by microbial laminae
and an external succession of crusts made by Broutinella arv-
ernensis and small protuberances of Brachydactylus reisi.
These compound nodules are typically formed by the super-
position of 2—4 algal-microbial generations. At the base of the
nodular build-ups, Chlorellopsis coloniata is common fre-
quent, composed of isolated, spheroidal cells embedded in a
bacterial micritic mass, generating microlaminations. In the
middle part of the nodules, crusts of Broutinella arvernensis
occur coated by or intermingled with Brachydactylus reisi. To-
wards the exterior, the successive microlaminations contain a
biocoenosis of Broutinella arvernensis, Ponsella freyteti and,
at the outer margin, many small protuberances made by
Brachydactylus reisi (Fig. 7).
The occurrence of these algal-stromatolite structures with-
in the Lower Serpulid Limestone is recorded here for the first
They represent lacustrine stromatolites accumulated on the
lacustrine shores. The stromatolitic nodules incorporate ser-
pulid tubes, disrupted ostracod valves, gastropod coprolites
(0.3—0.4 mm in length), and microbial pellets. At the top, or
between the algal nodules, occur clay and limestone clasts,
3.0—4.0 mm in length, elongated and flattened in shape, to-
gether with abundant detritic quartz, 0.010—0.10 mm in di-
The Lower Serpulid Limestone (LSL) includes tubes of
Serpula selectively transported and deposited in monospecif-
ic banks, some of them being incorporated in stromatolite
nodules or serving as substrates for other algal-microbial
The community belonging to the LSL indicates a fluctuat-
ing salinity, from hypersaline to limnic, in the peritidal envi-
ronment (Fig. 4).
c) Stromatolite community (localities 2, 3) of the inter-
tidal and proximal supratidal zones.
This community was dominated by algae and represented
by spheroidal or ellipsoidal nodules with or without a core of
1—2 tubes of serpulids on which were fixed thalli crossed by
dichotomous tubes with swellings of Springerella bifurcata
n.sp. or rarely S. fuchtbaueri n.sp.
The majority of these algal nodules were free on the sub-
stratum or were temporarily anchored when larger.
The spheroidal thalli of Springerella bifurcata (Figs. 5—6),
with or without a core, never surpassed 2.5—3.0 mm. The
thalli had ellipsoidal shapes, when the substratum or the core
was made of two serpulid tubes, and dimensions larger than
The majority of the nodules of the Upper Serpulid Lime-
stone can be regarded as homogenous, monospecific stromat-
olites. Nodules larger than 6.0—10.0 mm, with an irregular
outline, with small external protuberances, occur rarely.
They are constructed by Springerella bifurcata to the central
part followed externally by laminated crusts of Broutinella
arvernensis. In most cases, the serpulid tubes provided the
better substratum for algae, such as dichotomously ramified
tubes of Springerella. The Springerella nodules incorporate
serpulid tubes, and angular quartz grains with a diameter of
In addition to Springerella and Broutinella, the community
includes bivalve shells, ostracod valves and microgastropods
(4.0—5.0 mm). The gastropod shells were filled with numer-
ous small serpulid tubes. Ooids also occur with cores of an-
gular quartz (0.05—0.06 mm in diameter) or of well rounded
quartz grains with a diameter larger than 0.80—1.0 mm.
Clusters of dead serpulids provided the initial substrates
for the nodules and laminated crusts. These crusts incorpo-
rate empty tubes of serpulids, algal pellets, ostracods, gastro-
pod shells, and quartz grains with a reduced diameter.
This community belonging to the Upper Serpulid Lime-
stone can be compared with the spirorbid algal stromatolites
and Recent stromatolites in hypersaline (50—70 ‰) lagoons
near Shark Bay, W. Australia (Ten Hove & Van Den Hurk
1993). The algal nodules of the Upper Serpulid Limestone in-
corporated re-deposited tubes of serpulids generated in la-
goons fringing an inland sea, within the intertidal and lower
Family Udoteaceae Endlicher 1834 emend. Agardh 1887
Genus Pseudopenicillus Dragastan, Richter, Kube, Popa,
Sârbu et Ciugulea 1997
Pseudopenicillus weseri nov. spec.
Derivatio nominis: from the Weser River, Germany.
Holotype: Fig. 9.1, Coll. L.P.B. V, No. 1120, Upper Titho-
nian, sample F3A, Oolitic Serpulid Limestone (Münder Marl
= OM 4) Salzhemmendorf.
Isotypes: Fig. 9.4—8, Coll. L.P.B. V, No. 1121, No. 1122, No.
1123, No. 1124, Upper Tithonian, Oolitic Serpulid Limestone.
Diagnosis: Thallus composed by cylindrical segments sepa-
rated by constrictions. The segments have a central medullary
hollow, without preserving siphons, and a thin cortex crossed
by cylindrical primary, secondary and tertiary siphons. Prima-
ry siphons have in the proximal part an inflated swollen “vesi-
cle”, and the secondary siphons also have small “vesicles” in
the distal parts. Tertiary siphons, dichotomic, are very short
Description: Thallus formed by small narrow, cylindrical
segments separated by deep constrictions (Fig. 9.1,6). The
segments, entire or broken, have an axial cavity with an un-
even and sinous contour. The central cavity is narrow and cor-
responds to the medullary zone, in which the siphons are not
preserved. The cortex is not thick, and partially is only incom-
plete preserved. It was not strongly calcified and sometimes is
broken (Fig. 9.4—8).
The cortical zone is crossed by very fine, cylindrical, prima-
ry siphons continued by secondary siphons, both dichoto-
mously branched. The vesiculiferous inflated proximal part of
primary, and of the distal part of secondary siphons, are clearly
visible on the Fig. 9.4 (see arrow).
Dimensions in mm: length of thallus: 2.0—3.0; diameter of
thallus: 0.90—0.95; diameter of thallus between segments:
0.70—0.75; diameter of the axial cavity or medulla: 0.50—0.55;
thickness of cortex: 0.15—0.20; length of primary cortical si-
phons: 0.080—0.10; length of secondary cortical siphons:
0.040—0.060; length of tertiary siphons: 0.020—0.030; diameter
of primary cortical siphon: in the proximal part 0.030 and in
the median and distal part: 0.020; diameter of secondary corti-
cal siphons in the distal part 0.010—0.015; diameter of tertiary
Discussion: Pseudopenicillus weseri n.sp. differs from P.
jurassicus (Dragastan), P. orientalis (Dragastan), P. elongatus
(Dragastan), P. texana (Johnson) and P. dragastani (Bucur) of
Late Jurassic—Early Cretaceous age, by the small size of the
segments and by the presence of “vesicle” in the proximal
parts of the primary siphons and in the distal parts of the sec-
ondary cortical siphons.
P. peloponnesiacus Dragastan et Richter from Tithonian,
Corinth area (Grecee), is similar in the small segment size and
presence of cylindrical primary and secondary cortical si-
phons, but lacks “vesicle” in the proximal and distal parts of
Springerella nov. gen.
Derivatio nominis: from Springe locality and from the
Type species: Springerella bifurcata nov. gen. nov. spec.
Diagnosis: Nodular thallus crossed by only one kind of
long tube, open or Y-shaped, dichotomously branched, hav-
ing a strong calcified swelling in the area of branching. Due
to the reduced number of swellings (1—2) between the suc-
cessive dichotomies and in the branching area, the thallus is
Discussion: The new taxon is comparable with non-ma-
rine genera Purserella Freytet 1997 (Oligocene), Ponsinella
Freytet 1998 (Ludian—Recent) and Sarfatigirella Freytet
Purserella has erect filaments, regular, flexuously sinuous,
dichotomous branches diverging at 30°, but lacks swellings
in the branching area and along the filament tubes.
Ponsinella has two types of filaments, prostrate, then in-
clined and erect, rarely branched with a lateral tube making
an angle of 60° (Freytet 1998, p. 21).
Sarfatigirella shows intricate filaments, arcuate, flexuous,
having a “pinch and swell” aspect, forma torulata, which dif-
fers in shape and thickness from the new taxon.
The new taxon is also comparable with the Jurassic species
of the marine Mitcheldeania Wethered 1886 and with
Pseudomitcheldeania Schlagintweit 1990 (Jurassic—Creta-
ceous) and Perachoraella Dragastan, Richter, Gielisch et
Kube 1998 (Late Jurassic—Early Cretaceous). These genera
also have dichotomously branched tubes (siphons) with a
small angle of divergence (mainly 10°) and variable swell-
ings, occurring in number, higher than two, and another
shape of swellings, which differ from the new genus.
The taxonomic attribution of the new genus within the
Chlorophyta remains open. The presence of swellings in the
tube siphons is a characteristic feature of Bryopsidophyceae.
Posinella is considered close to modern Scytonemataceae
(Cyanobacteria) and Purserella still remains in an open tax-
onomy (Freytet 1997 and 1998).
The genera Mitcheldeania, Pseudomitcheldeania and Per-
achoraella belong the Family Avrainvilleaceae, Class Bry-
NON-MARINE CALCAREOUS ALGAE OF JURASSIC TO CRETACEOUS SEQUENCES 311
Fig. 10. 1: Springerella bifurcata nov. gen. nov. spec., Holotype, Coll. L.P.B. V, No. 1125, cross-section of a nodular oval—ellipsoidal thal-
lus, sample 835. 2: Springerella bifurcata nov. gen. nov. spec., Isotype, a vertical section of a nodular, spheroidal thallus attached to a ser-
pulid tube, showing the characteristic dichotomic branched tubes with swellings separated by constrictions. 3: Springerella bifurcata nov.
gen. nov. spec., Isotype, cross-section of an ellipsoidal thallus, showing the distribution pattern of the tubes, locally with large, circular
swellings, strongly calcified. Lower Berriasian, Upper Serpulid Limestone, Springe locality, Weserbergland, NW Germany.
Fig. 11. 1—4: Springerella bifurcata nov. gen. nov. spec., Isotypes; 1—3. Thalli variously sectioned with or without nuclei, mainly occurring
on serpulids tubes, showing the Y-shaped dichotomic tubes, like Ortonella, slightly moniliformous, with marked swelling, in the branching
area; 4. Two generations of thalli covering the serpulids tubes: normal thalli growing to the extremities (n) and small, young thalli (s) occu-
pying the “depression” formed between the tubes of serpulids, sample 835. 5—7: Springerella fuchtbaueri nov. spec.; 5. Holotype, Coll.
L.P.B. V, No. 1132, vertical axial section, in bushes attached to serpulid tubes and showing characteristic shape of swellings, sample 38; 6.
Isotype, horizontal cross-section, showing the shape of thallus and characteristic distribution pattern of the tubes; tubes disposed in a peta-
loid – subpolygonal structure with large diameter (light spots); 7. Isotype, oblique cross-section in thallus composed of strongly calcified,
dichotomously branched tubes. Lower Berriasian, Upper Serpulid Limestone, Springe locality, Weserbergland, NW Germany.
NON-MARINE CALCAREOUS ALGAE OF JURASSIC TO CRETACEOUS SEQUENCES 313
Springerella bifurcata nov. spec.
(Fig. 10.1—3, Fig. 11.1—4)
Derivatio nominis: from the open dichotomously branched
Holotype: Fig. 10.1, Coll. L.P.B. V, No. 1125, Lower Berri-
asian, sample No. 835, Upper Serpulid Limestone, locality
Isotypes: Fig. 10.2—3, Coll. L.P.B. V, No. 1126, No. 1127;
Fig. 11.1—4, Coll. L.P.B. V, No. 1128, No. 1129, No. 1130, No.
1131, Lower Berriasian, Upper Serpulid Limestone.
Diagnosis: Nodular thallus composed of Y-shaped, open,
dichotomously branched tubes, having in the area of branching
a strongly calcified swelling and 1—2 swellings along the tubes
in the area between two successive dichotomous branches.
Description: Nodular spheroidal or ellipsoidal thallus. The
shape of the thallus reflects the shape of the core or substra-
tum. If the alga is attached on a serpulid tube, the shape of
thallus is spheroidal (Fig. 10.2). When it is attached on an
elongate ooid, the shape of thallus becomes ellipsoidal or if is
embedded on a double serpulid tubes, the shape of thallus is
also ellipsoidal (Fig. 11.4). The thallus is crossed by long, Y-
shaped open dichotomously branched tubes, which present an
angle of divergence of 30°—40°. In vertical (Fig. 10.1—2) and
horizontal sections (Fig. 10.3) the Y-shaped, dichotomous
tubes present in the branching area a strong swelling and also
1—2 swellings along the tubes, between two successive dichot-
omously branched areas (Fig. 10.2; Fig. 11.3). The shape of
swellings is ovoidal to ellipsoidal between the dichotomies
and subtriangular in the branching area (Figs. 5—6).
The pattern of distribution of the tubes is another character-
istic feature of this species. In cross-section, the tubes are dis-
posed in a regular network, round, quadrangular or polygonal
in shape, separated from each other by coarsely crystalline cal-
cite (Fig. 10.3). The distribution of tubes is in a more or less
regular sparitic “muff”, represented by 4 (quadrangular) or 8
tubes, when the shape of “muff” is round to polygonal, the
tubes having a petaloid disposition (Fig. 10.3). Sometimes in
horizontal section, the swellings appear circular with a large
diameter, like white sparitic spots (Fig. 10.3).
Dimensions in mm: maximum diameter of thallus: 3.5—4.0;
normal diameter of thallus: 2.20—3.0; diameter of tube in the
dichotomous branching area: 0.075—0.080; diameter of tube
after the dichotomous branching area: 0.035—0.040; diameter
of swellings along the tube: 0.040—0.050; angle of divergence:
Discussion: Springerella bifurcata n.sp., differs from Purse-
rella gracilis Freytet (Oligocene) by the presence of swellings
in the branching area and in other kinds of dichotomy. From
Ponsinella rupestris Freytet (Recent), it differs in the absence
of two kinds of filaments, prostate and then erect.
Sarfatigirella fallacia Freytet from the Campanian differs in
its small diameter of more or less erect filaments, that are not
undulose. In common with the new species swellings are
present, but these are not distributed in the branching area, and
they also have a spheroidal shape.
The marine species Mitcheldeania americana (Johnson)
from the Jurassic differs from the new taxon by the presence of
siphons, dichotomously branched after an angle of divergence
of less than 10°, and by the presence of many swellings along
The marine species of Pseudomitcheldeania such as P. dra-
gastani Schlagintweit (Upper Aptian), P. akrokorinthica Dra-
gastan et Richter (Tithonian) and P. sp. (Valanginian) are dif-
ferent from S. bifurcata, in their shape and in the number of
swellings along the tube. The first of these species has many
swellings along the tube and the second species has long, large
swellings arranged at different levels. The third species has el-
lipsoidal swellings, distributed at irregular intervals along the
tubes. The species of Pseudomitcheldeania belongs to the
Family Avrainvilleaceae, Class Bryopsidophyceae.
Springerella fuchtbaueri nov. spec.
Derivatio nominis: Species dedicated to Dr. Hans Fücht-
bauer, Professor Emeritus of the Institute of Geology, Ruhr
University Bochum, who first studied the algal-microbial nod-
ules of Weserbergland, NW Germany.
Holotype: Fig. 11.5, Coll. L.P.B. V, No. 1132, Lower Berri-
asian, sample No. 38/1, Upper Serpulid Limestone, Springe
Isotypes: Fig. 11.6—7, Coll. L.P.B. V, No. 1133 and No.
1134, Lower Berriasian, Upper Serpulid Limestone.
Diagnosis: Thallus ellipsoidal, composed of several fan-
shaped bushes. Each bush crossed by short, dichotomously
branched tubes with strongly calcified sub-triangular or clavi-
form swellings, before the branching zone (Fig. 11.5c). The
tubes show many spheroidal swellings between successive di-
chotomies (Fig. 11.5, see arrows). The angle of divergence
varies from 10° to 40°.
Description: Thallus irregular ellipsoidal, formed by sever-
al spheroidal or fan-shaped bushes fixed on the serpulid tubes
(Fig. 11.6). Thallus is crossed by dichotomously branched
tubes, having a subtriangular or claviform swellings (Fig.
11.5). In the horizontal and oblique-horizontal sections (Fig.
11.6—7), the arrangement of tubes is subpolygonal, composed
of over 8 circular tubes (Fig. 11.7). The swellings before the
branching area have a large diameter.
Dimensions in mm: height of thallus: 0.30—0.70; width of
thallus: 0.40—0.90; tube diameter, in the dichotomic branching
area: 0.040—0.060; tube diameter after dichotomic area:
0.020—0.030; diameter of basal swelling before branching:
Discussion: Springerella fuchtbaueri nov. spec. differs from
the non-marine species, Purserella gracilis Freytet, Ponsinella
rupestris Freytet and Sarfatigirella fallacia Freytet by the
presence of dichotomic tubes which in the branching area have
a strong calcified swelling and many small swellings separated
by constrictions along the tubes crossing the thallus. S. bifur-
cata nov. spec. is different in the shape of thallus, pattern dis-
tribution of tubes, angle of divergence and pattern of distribu-
tion of swellings along the thallus.
In comparison with marine species, the new species is com-
parable with Mitcheldeania americana (Johnson) of the Upper
Jurassic, but differs in having a different kind of branching and
fewer swellings along the tubes. It differs from Pseudomitch-
eldeania dragastani Schlagintweit (Upper Aptian), in the
shape of the thallus and the shape and distribution of swellings
crossing the thallus.
Genus Chlorellopsis Reis 1923
Chlorellopsis coloniata Reis 1923
1923 Chlorellopsis coloniata n.gen. n.sp., Reis, p. 107, Tafel III,
2, 9; Tafel IV, Figs. 3,6; Tafel V, Figs. 2
6 and Fig.
Text 1, p. 105
1997 Chlorellopsis coloniata, Freytet, p. 13, Pl. 1, Figs. a
2000 Chlorellopsis coloniata, Freytet, p. 9, Pl. I, Fig. c
Paratype: Fig. 12.2, Coll. L.P.B. V, No. 1135, Lower Berri-
asian, sample A3, Lower Serpulid Limestone, Deister Mts,
Weserbergland, NW Germany.
Description: Thallus small, nodular, in biomicritic masses
or included in laminations. Thallus is composed of spherical
bodies (cells), 0.060—0.110 mm in diameter. The spherical
“cells” are preserved in coarsely crystalline calcite surrounded
by microcrystalline calcite, polygonal in shape (Fig. 12.2).
The microcrystalline calcite “layer” is covered by coarse crys-
talline calcite like a “muff” which preserves the polygonal
shape of the cells (Fig. 12.1/c—2).
Dimensions in mm: diameter of thallus: 1.0—2.0; diameter
of spherical bodies or cells: 0.060—0.110.
Remarks: Chlorellopsis coloniata is a frequent alga in the
brackish and freshwater facies mainly associated with stroma-
A discussion and interpretation of Ch. coloniata was well
presented by Freytet (2000) who shows that Chlorellopsis is
never free in the sediment when building stromatolitic masses
showing diverse aspects and morphologies.
The systematic position of Ch. coloniata is and remains
– Reis (1923) considered that the species belongs to Chlo-
rophyta, Order Protococcales and compared it with the Recent
marine genus Halosphaera and with freshwater genera Eremo-
sphaera and Chlorella;
– Lindqvist (1994) considers that these thalli with spheres
are “endogonaceous fungal spores” and
– Freytet (1997) shows that a precise attribution of Chlo-
rellopsis coloniata remains open.
Genus Brachydactylus Reis 1923
Brachydactylus reisi nov. spec.
(Fig. 12.1, Fig. 13.1—6)
Derivatio nominis: Species dedicated to Otto M. Reis, who
was the first to discover and describe the Miocene non-marine
Holotype: Fig. 13.1, Coll. L.P.B. V, No. 1138, Lower Berri-
asian, sample A3, Lower Serpulid Limestone, Deister Mts,
Weserbergland, NW Germany.
Isotypes: Fig. 13.4—6, Coll. L.P.B. V, No. 1139, No. 1140
and No. 1141, Lower Berriasian, Lower Serpulid Limestone,
Weserbergland, NW Germany.
Diagnosis: Thallus crossed by a bunch of filaments grouped
in fascicles composed of finger-like, short dichotomic fila-
ments. The fascicles grow over each-other. They have a fan-
shape, being cauliflower-like in structure, and minidigitate at
the distal part of the fascicles.
Description: Thallus nodular with many small, spheroidal
protuberances. The thallus is crossed by grouped filaments
with microdigitate distal ends of the fascicles (Fig. 13.1—6).
Each filament fascicle is strongly calcified with a fan-shaped
aspect and comprise many, small, dichotomic filaments at the
distal part (Fig. 13.3—6). The fascicle filaments form spherical
nodules (Fig. 13.1,4) or planar laminated crusts (Fig. 13.6).
Dimensions in mm: diameter of the thallus nodule: 2.0—
2.5; diameter of isolated protuberances: 1.0—1.5; width of the
filament fascicles: 0.70—0.75; height of the filament fascicles:
0.40—0.50; diameter of minidigitate filaments in the distal part:
Discussions: Brachydactylus reisi n.sp. differs from the Mi-
ocene B. radialis Reis in the shape and size of filament fasci-
cles, which contain dichotomic filaments at the distal parts of
B. reisi n.sp. is one the most important builders of the stro-
matolitic nodules, being associated with and a generator of
crusts (protuberances), together with Chlorellopsis coloniata
Reis, Broutinella arvernensis Freytet and Ponsella freyteti
n.sp. (Fig. 7).
Genus Ponsella Freytet 1997
Ponsella freyteti nov. spec.
Derivatio nominis: Species dedicated to Dr. Pierre Freytet
for his contributions in the field of non-marine algae.
Holotype: Fig. 12.3, Coll. L.P.B. V, No. 1136, Lower Berri-
asian, sample A3, Lower Serpulid Limestone, Deister Mts,
Weserbergland, NW Germany.
Isotype: Fig. 12.5, Coll. L.P.B. V, No. 1137, Lower Berri-
asian, Lower Serpulid Limestone, Weserbergland, NW Ger-
Diagnosis: Thallus laminated, crustose, composed of fila-
ments grouped in fascicles at the base, inclined, then erect, be-
ing slightly dichotomously branched; adjacent fascicles form-
ing layers or lamination.
Description: Thallus crustose, laminated, not very thick,
formed by fascicles. The filaments disposed at the base, pros-
tate short, then erect (Fig. 12.4—5). The fascicles are wide, cy-
lindrical, composed of 2 or 4 slightly dichotomic branched fil-
Dimensions in mm: thickness of thallus: 0.30—0.50; width
of the fascicles: 0.070—0.10; diameter of filament tubes:
Discussion: Ponsella freyteti nov. spec. is close to P. castel-
landonica Freytet 1997 from Ludian, in filament size, but dif-
fers in the shape and the size of the fascicles, which are not so
wide. The species P. sezanensis Freytet 1997 and P. cupulata
Freytet 1997 from the Eocene have different size and shape of
NON-MARINE CALCAREOUS ALGAE OF JURASSIC TO CRETACEOUS SEQUENCES 315
Fig. 12. 1: Stromatolitic nodule formed by algal crusts and different generations of algae as follows: at the base Chlorellopsis coloniata Reis
(c), in the middle and up to the upper part of the nodule Brachydactylus reisi nov. spec. (b), Broutinella arvernensis Freytet (br), Ponsella
freyteti nov. spec. (p) appear successively and at the top of the nodule some protuberances with Brachydactylus reisi nov. spec. (b). 2: Chlo-
rellopsis coloniata Reis, Paratype, thallus subspheroidal formed by spherical cells (c), which shows a polygonal, microcrystalline calcite in-
ter-space and a sparitic outer “muff”. 3—5: Ponsella freyteti nov. spec.; 3. Holotype, Coll. L.P.B. V, No. 1136, vertical section, a laminated
crust, crossed by micritic tubes filaments (p), homogenous, slightly inclined to the base, subsequently erect, grouped in fascicles. Ponsella
grew over Brachydactylus reisi nov. spec. (b); 4. Detail in Holotype, typical aspect of the base with micritic filaments (b) and very narrow
fascicles (f) with erect coarsely crystalline calcite filaments; 5. Isotype, thallus laminated at the base, prostate with micritic filaments and subse-
quently erect filaments grouped in fascicles. Lower Berriasian, Lower Serpulid Limestone, Dreister Mts., Weserbergland, NW Germany.
Fig. 13. 1—3: Brachydactylus reisi nov. spec.; 1. Holotype, Coll. L.P.B. V, No. 1138, vertical section, thallus nodular built by small, cauli-
flower, spheroidal fascicles overgrowing each other, sample A3; 2—3. Detail of Holotype showing the distribution of cauliflower-like, sphe-
roidal fascicles; fascicles appear dichotomic short fingers, tubular filaments. 4—6: Brachydactylus reisi nov. spec.; 4. Isotype, cross-section
in a nodule formed by radially disposed cauliflower-like fascicles which have distal finger-like short, dichotomic filaments; 5—6. Vertical
section, in laminated nodule showing the overgrowing of the cauliflower-like, filamentous fascicles. Lower Berriasian, Lower Serpulid
Limestone, Dreister Mts, Weserbergland, NW Germany.
NON-MARINE CALCAREOUS ALGAE OF JURASSIC TO CRETACEOUS SEQUENCES 317
fascicle, and also are different from the new taxon in filament
Genus Broutinella Freytet 1998
Broutinella arvernensis Freytet 1998
(Fig. 12.1/br, Fig. 7)
1998 Broutinella arvernensis n.gen. n.sp. Freytet, p. 11, Pl. XII,
Paratype: Fig. 12.1/br, Coll. L.P.B. V No. 1142, Lower
Berriasian, sample A3, Lower Serpulid Limestone, Weserber-
gland, NW Germany.
Description: Thallus crustose, laminated, formed by only
one layer (forma monostrata) with fascicles various in shape,
including diverse shapes of coarse crystalline calcite (sparite
radial, palisadic). The crust shows frequent intervals of micro-
laminations. Filaments very thin, 3—5
m in diameter.
Remarks: Broutinella arvernensis is the main organism of
the stromatolitic build-ups, forma monostrata, and it is fre-
quently associated with Chlorellopsis coloniata, Ponsella
freyteti nov. spec. and Brachydactylus reisi nov. spec.
Freytet (2000) shows that the three discriminating charac-
ters of B. arvernensis are the scarce presence of erect, more or
less radiating filaments; lamination of radial, palisadic sparite;
and the frequent presence of microlaminations in the light lam-
inae. The presence of radial palisadic type of calcite in fresh-
water facies suggests travertines or sinter crusts with periodic
proliferation of population of cyanobacteria or other bacteria.
Acknowledgments: The authors wish to express their grati-
tude to Dr. P. Freytet (France) and to Dr. R. Riding (England)
for their valuable comments and criticism.
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