inhabited mainly by freshwater species such as Carbonita scalpellus and C. rankiniana. Foraminifera were recorded only in the coastal marsh, and they were
represented exclusively by agglutinated species of Trochammina sp., as the dominant species, and by Ammobaculites sp., Ammotium sp. and Ammodiscus sp. which
were less abundant.
A similar ecological system in Nova Scotia was studied by Calder (1998). The
Blue Beach Member was interpreted as a near-shore basin periodically connected to
the sea. During the onset and peak of marine transgression diverse species of Fusulinina and Miliolina foraminifers were recorded in association with marginal marine
ostracod species belonging to the Palaeocopida and Bairdiacea. With the gradual
withdrawal of the marine influence a retreat of marine fusulinids and increasing
dominance of agglutinated Textulariidae (mainly Trochammina, Ammobaculites and
Ammodiscus) occurred. Under low salinity conditions the ostracod assemblage also
changed. Marine species were replaced with euryhaline Paraparchites and Cavellina,
the brackish Geisina, and by freshwater species of Carbonita.
In the Devonian to Permian deposits of the Brabant Massif in Belgium the
shallow near-shore environment was inhabited by a mixed marine ostracod
assemblage represented mainly by rare bairdiacean ostracods (notably Bairdia and
Acratia) (Bless et al. 1988). However, because of the absence of fusulinid foraminiferans this environment was interpreted as “less open marine environment”. The
brackish water setting of the deltaic system under marine incursion was inhabited
by brackish Geisina and freshwater Carbonita species associated with agglutinated
forms of Foraminifera (Ammodiscus and Hyperammina). Generally, the majority of
Early Carboniferous fossil evidences of both, agglutinated and Fusulinida Foraminifera come from North America, Canada and Western Europe, with fewer records
from Asia and Australia (Fig. 1).
In modern environments a similar pattern is observed. Hedberg (1934) recorded
arenaceous (agglutinated) and calcareous Foraminifera in freshwater habitats in
Venezuela. Foraminifera were collected from Lake Maracaibo which is connected
with Caribbean Sea by a narrow neck, although salinity of this water body was low
(≈1 ‰). In freshwater habitats Hedberg (1934) found three groups of Foraminifera:
agglutinated (arenaceous) forms belonging to the Lituolidae, Trochamminidae and
Textulariidae; pelagic and benthic forms (Globigerina, Bulimina and Uvigerina),
the occurrence of these marine species was viewed as a result of transportation by
tidal currents; and euryhaline species (Rotalia beccari, Elphidium sp.) with Quinqueloculina fusca as a dominant species. Quinqueloculina fusca has also been
reported in Tertiary sediments together with brackish water molluscs as an associated group, and in the absence of marine fauna.
Holzmann and Pawlowski (2002) found naked forms of allogromids in Lake
Geneva and two other freshwater bodies in Switzerland. Authors obtained foraminiferal DNA sequences which clustered with a clade of saccamminid Foraminifera. Holzmann and Pawlowski also examined the 19th-century collection of
Eugene Penard. Five freshwater species of Penard’s Gromia could be distinguished
according to type of agglutinated test (covered with small, siliceous particles).
The Adaptations of the Foraminifera and Ostracoda …
95
represented exclusively by agglutinated species of Trochammina sp., as the dominant species, and by Ammobaculites sp., Ammotium sp. and Ammodiscus sp. which
were less abundant.
A similar ecological system in Nova Scotia was studied by Calder (1998). The
Blue Beach Member was interpreted as a near-shore basin periodically connected to
the sea. During the onset and peak of marine transgression diverse species of Fusulinina and Miliolina foraminifers were recorded in association with marginal marine
ostracod species belonging to the Palaeocopida and Bairdiacea. With the gradual
withdrawal of the marine influence a retreat of marine fusulinids and increasing
dominance of agglutinated Textulariidae (mainly Trochammina, Ammobaculites and
Ammodiscus) occurred. Under low salinity conditions the ostracod assemblage also
changed. Marine species were replaced with euryhaline Paraparchites and Cavellina,
the brackish Geisina, and by freshwater species of Carbonita.
In the Devonian to Permian deposits of the Brabant Massif in Belgium the
shallow near-shore environment was inhabited by a mixed marine ostracod
assemblage represented mainly by rare bairdiacean ostracods (notably Bairdia and
Acratia) (Bless et al. 1988). However, because of the absence of fusulinid foraminiferans this environment was interpreted as “less open marine environment”. The
brackish water setting of the deltaic system under marine incursion was inhabited
by brackish Geisina and freshwater Carbonita species associated with agglutinated
forms of Foraminifera (Ammodiscus and Hyperammina). Generally, the majority of
Early Carboniferous fossil evidences of both, agglutinated and Fusulinida Foraminifera come from North America, Canada and Western Europe, with fewer records
from Asia and Australia (Fig. 1).
In modern environments a similar pattern is observed. Hedberg (1934) recorded
arenaceous (agglutinated) and calcareous Foraminifera in freshwater habitats in
Venezuela. Foraminifera were collected from Lake Maracaibo which is connected
with Caribbean Sea by a narrow neck, although salinity of this water body was low
(≈1 ‰). In freshwater habitats Hedberg (1934) found three groups of Foraminifera:
agglutinated (arenaceous) forms belonging to the Lituolidae, Trochamminidae and
Textulariidae; pelagic and benthic forms (Globigerina, Bulimina and Uvigerina),
the occurrence of these marine species was viewed as a result of transportation by
tidal currents; and euryhaline species (Rotalia beccari, Elphidium sp.) with Quinqueloculina fusca as a dominant species. Quinqueloculina fusca has also been
reported in Tertiary sediments together with brackish water molluscs as an associated group, and in the absence of marine fauna.
Holzmann and Pawlowski (2002) found naked forms of allogromids in Lake
Geneva and two other freshwater bodies in Switzerland. Authors obtained foraminiferal DNA sequences which clustered with a clade of saccamminid Foraminifera. Holzmann and Pawlowski also examined the 19th-century collection of
Eugene Penard. Five freshwater species of Penard’s Gromia could be distinguished
according to type of agglutinated test (covered with small, siliceous particles).
The Adaptations of the Foraminifera and Ostracoda …
95