Study on morphology, ecology, biogeography and systematics of primitive ostracod Platycopa
| Project/Area Number |
11640693
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
系統・分類
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| Research Institution | Shizuoka University |
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Principal Investigator |
TSUKAGOSHI Akira Department of Biology and Geosciences, Shizuoka University Associate Prof., 理学部, 助教授 (90212050)
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| Project Period (FY) |
1999 – 2001
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| Project Status |
Completed (Fiscal Year 2001)
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| Budget Amount *help |
¥3,600,000 (Direct Cost: ¥3,600,000)
Fiscal Year 2001: ¥1,200,000 (Direct Cost: ¥1,200,000)
Fiscal Year 2000: ¥600,000 (Direct Cost: ¥600,000)
Fiscal Year 1999: ¥1,800,000 (Direct Cost: ¥1,800,000)
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| Keywords | Ostracoda / Crustacea / Living fossil / Evolution / Ontogeny / Comparative anatomy / Ostracoda / ベントス / segmentation / living fossil / Benthos / 個体発生 / Ostraconda / Segmentation / Bonthos |
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| Research Abstract |
This research focused on Keijcyoidea sp. which is a taxon of primitive ostracod Platycopa from Japan.
There is no report on the ecology and habitat of Platycopa at all. In the experience, the largest number of individuals were collected from the sediments which attached around the rhizoid of Eisenia bicyclis. In order to know the habitat and behavior in detail, some living specimens were observed. As a result, the following facts became clear : they use only antennule, antenna and furcae for moving ; their habitat in not surface but between coarse sand grains. It is suggested that other Platycopa species must have almost the same life style because the basic body plan of them is common to the Keijcyoidea sp
The following points of ontogeny and comparative anatomy were made clear. These knowledge will support the understandings of evolution on the primitive ostracod Platycopa.
1) They have 9 instars in ontogeny. 2) Copulatory organs of both sexes appear in A-3 (6th instar) as anlagen and the sexual dimorphism is observed in and after this stage. 3) Diagnostic characters of this taxon e.g. articulate trunk, bi-ramous antenna appear in the early stages. 4) They have nauplius eyes. 5) the anal opening are located at not dorsal side but ventral side. 6) An unit exists after the anal segment ; it is a telson. 7) The telson derives a pair of limb-like organ 'furcae' which is not homologous to 'caudal rami' in Podocopina. 8) furcae continue to develop until the final moult. 9) The copulatory organs of both sexes are derived from the 4th trunk segment.
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Report
(4 results)
Research Products
(6 results)
