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ABSTRACTS
Anne C. Cohen, Louis S. Kornicker, and
Thomas M. Iliffe,
2000, Jimmorinia, a new genus of myodocopid ostracoda (Cypridinidae)
from the Bahamas, Jamaica, Honduras, and Panama: Smithsonian Contributions to Zoology, 605: 1-46.
A new genus and two new species of marine Ostracoda (Myodocopina:
Cypridinidae), collected mostly from baited traps in the waters of the
Bahamas and Caribbean Sea, are described and illustrated.
Jimmorinia gunnari, the type species, is
non-luminescent, and was captured at 88-99 m depth on a submarine
escarpment in Exuma Sound near Lee Stocking Island and Great Exuma
island, Exuma Cays, Great Bahama Bank, Bahamas, and from shallower
depths (3-15 m) off Discovery Bay, Jamaica, Roatan Island, Honduras,
and the San Blas Islands, Panama, whereas J. gamma was
collected only near Lee Stocking Island.
Descriptions for adult females are given for both species, and
descriptions of adult males and some juvenile stages are given for J.
gunnari. Some sexual
and geographic variation is described.
A table of generic comparisons is presented. Some specimens of the new genus were tested and found to be
non-luminescent. Jimmorinia
has an upper lip with fewer glandular processes (nozzles) than are
present on the lips of Caribbean bioluminescent species.,
This paucity of nozzles may be related to a lack of
bioluminescent capacity. The
reduced number of ommatidia, very unusual in a cypridinid from shallow
depths, may be related to the lack of luminosity, or perhaps it
indicates an ancestral relationship to cypridinids from greater depths
or from an anchialine cave.
Sanad A. Al-Khashab,
Lower Cretaceous Ostracoda from selected boreholes in Central Iraq.
Ostracoda of Zangura, Garagu, Ratawi, and Zubair
Formations from boreholes Makhul-2, Balad-2 and East Baghdad-1 have
been studied in detail. One
hundred and siz species and subspecies belonging to 28 genera are
described, including 5 new species and one species were renamed.
These 28 genera are: Asciocythere,
Bairdia, Candoniella, Centrocythere, Curfsina, Cythereis, Cytherella,
Cytherelloidea, Dolocytheridea, Eocytheropteron, Euryitcythere, Indet.
Gen., Isocythereis, Macrocypris, Matronella, Metacytheropteron,
Neocythere, Paijenborchellina, Paracypris, Pontocyprella,
Protobuntonia, Pseudophanasymmetrica, Pterygocythere, Rehacythereis,
Schuleridea, Spinoleberis, Strigosocythere, Veenia.
Three biozones (assemblage biozones) were established
on the basis of the ostracod species occurrence.
These are:
1—Schuleridea cf. punctatula Biozone (Zangura
Formation) which confirmed late Berriasian-Early Valanginian age in
the studied section;
2—Schuleridea cf. obtabilis Biozone (Garagu and
Ratawi Formations) which confirmed Late Valanginian- Hauterivian
age in the studied section;
3—Cythereis libanensis Biozone (Zubair Formation)
which confirmed Barremian-Early Albian age in the studied sections. The paleoecology of Zangura Formation is shallow
marine environment with interference of brackish representing littoral
to inner sublittoral environments, warm water under normal sea water
salinity. Garagu
Formation representing by shallow marine environment with warm water
and normal salinity. Ratawi
Formation indicates an inner platform with redox environment.
While Zubair Formation representing different types of deltaic
environment. The
ostracode genera migrated from east to west as well as from west to
east and we concluded that the Trans-Sahara seaway has been present
since Pre-Albian age, and some of the genera use the deep-sea barrier
to migrate between Iberia and North Africa. The affinities of the described species are discussed from a
paleogeographical viewpoint, indicating that there are three
bio-provinces in south Europe, north Africa, and the Middle East (Iraq
and Iran).
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