radiolaria - Marum

Radiolaria 14 Bibliography - 1993
Aitchison, J.C. 1993b. Devonian (Frasnian) Radiolarians
from the Gogo Formation, Canning Basin, Western Australia.
Palaeontographica Abt. A, 228, 105-128.
A diverse and remarkably well-preserved Frasnian radiolarian
fauna is described from carbonate concretions of the Gogo
Formation, Canning Basin, Western Australia. It is the best
preserved, most diverse Frasnian assemblage yet documented with
57 species (41 new) assigned to 14 genera described. All elements
of the fauna are common but it is dominated by ceratoikiscids of
which 11 are new species. New species described include:
Ceratoikiscum patagiatum n.sp., Ceratoikiscum spiculatum n.sp.,
Ceratoikiscum fragile n.sp., Ceratoikiscum canningense n. sp.,
Ceratoikiscum robustum n. sp., Ceratoikiscum marginatum n. sp.,
Ceratoikiscum echinatum n. sp., Ceratoikiscum torale n.sp.,
Ceratoikiscum stellatum n.sp., Ceratoikiscum pillaraense n.sp.,
Helenifore gogoense n.sp., Entactinia hystricousa n.sp., Entactinia
gogoense n. sp., Entactinia aperticuvas n. sp., Entactinia pillaraense
n. sp., Entactinia profundisulcus n. sp., Entactinia proceraspina n.sp.,
Entactinosphaera australis n.sp., Entactinosphaera aculeatissime
n.sp., Entactinosphaera? robusta n.sp., Spongentactinia concinna n.
sp., Spongentactinia exquisita n. sp., Polyentactinia invenusta n. sp.,
Polyentactinia tenera n. sp., ? Astroentactinia radiata n. sp.,
Helioentactinia stellaepolus n.sp., Helioentactinia aster n.sp.,
Somphoentactinia cavata n.sp., Spongentactinella intracta n.sp.,
Spongentactinella abstrusa n.sp., Seccuicollacta labyrinthica n.sp.,
Secuicollacta araneam n.sp., Palaeoscenidium venustum n.sp.,
Palaeoscenidium robustum n.sp., Palaeoscenidium echinatum n.sp.,
Palaeoscenidium nudum n.sp., Palaeoscenidium daktylethra n.sp.,
Palaeoscenidium tabernaculum n.sp., Palaeoscenidium phalangium n.
sp., Palaeoscenidium delicatum n.sp., Paleotripus gogense n. sp.
Alder, V.A. & Boltovskoy, D. 1993. The ecology of
larger microzooplankton in the Weddell-Scotia confluence
area: horizontal and vertical distribution patterns. J. marine
Res., 51/2, 323-344.
The distribution of microzooplankton >15µm (large
dinoflagellates, foraminifers, radiolarians, tintinnids,
microcrustaceans and various Invertebrate larvae) was studied in
samples retrieved from 10 to 400 m in two overlapping transects
along 49 W, between 57°S and 61°30'S (27 Nov.-12 Dec. 1988, and
27 Dec. 1988-4 Jan. 1989). For each sample approx. 10 litres of
water were concentrated with a 15 µm-mesh sieve and counted
under an inverted microscope. Biomass estimates were based on
measurements of cell dimensions. Dinoflagellates and tintinnids
concentrated at 50-90 m (10-400 m weighted averages,
dinoflagellates: 103 ind./l, 131 mg C/m 2 ; tintinnids: 9.7 ind./l, 53
mg C/m 2 ). Copepod nauplii had a more variable vertical pattern with
maximum numbers at 100-200 m (10-400 m av.: 2.6 ind./l, 27 mg
C/m 2 ). Foraminifers and radiolarians were most abundant in
noticeably deeper waters peaking below 150 m (10-400 m av.,
foraminifers: 0.2 ind./l, 11 mg C/m2; radiolarians: 2.7 ind./l, 12 mg
C/m 2 ). Large dinoflagellates accounted, on the average, for 55% of
the biomass of the heterotrophs considered in the 10-400 m layer,
followed by the tintinnids (23%), Copepod nauplii (11%),
foraminifers (5X), and radiolarians (5X). The 100-400 m layer
hosted up to 87% (mean: 49X) of total 10-400 m integrated
microzooplanktonic biomass, and limited data for depths over 400 m
indicate that these strata can contribute significantly (up to 50%)
to total organic carbon, especially at the less fertile locales. The
distribution of loricate ciliates was strongly correlated with those of
chlorophyll a, and especially dinoflagellates (r=0.832, for logtransformed
data), suggesting close trophic relationships between
these two groups. The northern sites were generally richer in
microzooplankton than the area closer to the ice-edge, and the
southernmost ice-covered zone yielded the lowest microplanktonic
values. This biological pattern, which was but loosely coupled with
the Weddell-Scotia Confluence, with the vertical stability of the
water column, and with near surface concentrations of chlorophyll a,
can at least partly be explained by differential grazing pressure by
crustacean mesozooplankton. The time elapsed between the two
transects did not affect the microzooplanktonic assemblages
noticeably. Comparisons with previous abundance estimated carried
out earlier and later in the growth season suggest that
microzooplanktonic abundances increase toward the late summerfall,
probably In response to enhanced availability of nano- and picosized
producers, characteristic of Antarctic post-bloom conditions.
Amon, E.O. 1993. Cretaceous Radiolaria of the Urals. In:
Radiolaria of giant and subgiant fields in Asia. Nazarov
Memorial Volume. (Blueford, J.R. & Murchey, B.L., Eds.),
Micropaleontology, special Publication vol. 6 .
Micropaleontology Press, American Museum of Natural
History, New York. pp. 66-71.
Radiolarians have a wide distribution in Cretaceous deposits
from the Great Urals region of the Russia eastern slope of the Urals,
and adjacent areas of the West Siberian plate. In the local area there
are 10 preliminary radiolarian zones that can be distinguished.
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Understanding the geologic history of this area requires a more
intense geographic and stratigraphic distribution study of
radiolarians, including correlation with the Russian Platform and
Atlantic Basin with respect to species and assemblage.
Anderson, O.R. 1993. The trophic role of planktonic
foraminifera and radiolaria. Marine Microbial food Webs,
7/1, 31-51.
Planktonic foraminifera and radiolaria are abundant in diverse
oceanic locations and at varying depths in the water column. They
are largely opportunistic feeders and generalists taking a wide
variety of prey spanning monera (eubacteria and cyanobacteria) to
protista and metazoan zooplankton (copepods, Larvacea, etc.).
Juvenile and adults of small species generally consume algal or
protistan prey. Most of the larger species of planktonic foraminifera,
and some radiolaria, are omnivorous based on current evidence. One
planktonic foraminiferan (Hastigerina pelagica) is carnivorous,
consuming zooplankton prey. Data on predators is limited, but based
on digestive tract samples from diverse geographic locations,
planktonic foraminifera and radiolaria have been detected in
tunicates (e.g., salps), crustacea such as copepods and euphausids,
and in certain penaeidae, among others. The co-occurrence of
diverse species of planktonic foraminifera and radiolaria in the same
locale suggests that these species do not differ substantially in
their trophic competitiveness. Furthermore, the presence of algal
symbionts (providing a primary source of nutrition), approximately
similar longevity, and lie-in-wait predatory strategies make them
trophically complementary rather than differentially competitive,
thus possibly accounting for their local diversity and high
abundance.
Bak, M. 1993a. Micropaleontological and Statistical
Analyses of the Albian and Cenomanian deposits based on
Radiolaria, Pieniny Klippen Belt, Carpathians. Bull. pol.
Acad. Sci. (Earth Sci.), 41/1, 13-22.
Fifty three species of Radiolaria from the Upper Albian-Lower
Cenomanian marly deposits of the Czorsztyn and Branisko
successions have been statistically analysed. Interdependence
between diversification of radiolarian faunas and black shale (anoxic
events) deposition was found. These Radiolaria assemblages
represent the Acaeniotyle umbilicata Zone.
Bak, M. 1993b. Late Albian-early Cenomanian Radiolaria
from the Czorsztyn succession Pieniny Klippen Belt,
Carpathians. In: Geology of the Pieniny Klippen Belt,
Carpathians, Poland. (Birkenmajer, K., Eds.), vol. 102.
Studia geologica polonica, Crakow, Poland. pp. 177-207.
Fifty three species of Radiolaria from the Upper Albian-Lower
Cenomanian marly deposits of the Czorsztyn Succession have been
analysed. The species determined belong to the orders Spumellaria
(12 species) and Nassellaria (41 species). The investigated
Radiolaria assemblages represent the Acaeniotyle umbilicata Zone.
Baumgartner, P.O. 1993. Early Creataceous radiolarians
of the Northeast Indian Ocean (Leg 123: Sites 765, 766 and
DSDP Sites 261): The Antarctic-Tethys connection. In:
Interrad VI. (Lazarus, D.B. & De Wever, P., Eds.), vol. 21.
Special Issue: Marine Micropal., Elsevier, pp. 329-352.
During ODP Leg 123, abundant and well-preserved Neocomian
radiolarians were recovered at Site 765 (Argo Abyssal Plain) and
Site 766 (lower Exmouth Plateau). Assemblages are characterized
by the numerical dominance of a small number of non-tethyan forms
and by the scarcity of tethyan taxa. Remarkable contrasts exist
between radiolarian assemblages extracted from claystones of Site
765 and reexamined DSDP Site 261, and faunas recovered from
radiolarian sand layers, only found at Site 765. Clay faunas are
unusual in their low diversity of apparently ecologically tolerant ( or
solution resistant?), ubiquist species, whereas sand faunas are
dominated by non-tethyan taxa. Comparisons with Sites 766 and
261, as well as sedimentological observations, lead to the
conclusion that this faunal contrast resulted from a difference in
provenance, rather than from hydraulic sorting or selective
dissolution.
The ranges of 27 tethyan taxa from Site 765 were compared to
the tethyan radiolarian zonation by Jud (1991) by means of the
Unitary Associations Method. This calculation allows to directly date
the Site 765 assemblages and to estimate the amount of truncation
of ranges for tethyan taxa. Over 70% of the already few tethyan
species of Site 765, have truncated ranges during the Valanginian-
Hauterivian. Radiolarian assemblages recovered from claystones at
Sites 765 and 261 in the Argo Basin apparently reflect restricted
oceanic conditions during the latest Jurassic-Barremian. Neither
sedimentary facies nor faunal associations bear any resemblance to