The University Museum
The University of Tokyo



Bulletin No.35


SUBMARINE CAVE BIVALVIA FROM THE RYUKYU ISLANDS:
SYSTEMATICS AND EVOLUTIONARY SIGNIFICANCE


Itaru HAYAMI and Tomoki KASE


1993 TOKYO





CONTENTS

Abstract
Introduction
Submarine Caves in the Ryukyu Islands
Systematic Description
Solemya (Petrasma) sp.
Huxleyia cavernicola sp. nov.
Pronucula insignis sp. nov.
Acar sp. aff. A. plicata (Dillwyn)
Bentharca tenuis sp. nov.
Bentharca decorata sp. nov.
Bentharca irregularis sp. nov.
Bentharca excavata sp. nov.
Bathyarca sp. indet.
Cosa waikikia (Dall, Bartsch and Render)
Cosa kinjoi sp. nov.
Cosa uchimae sp. nov.
Cosa sp. indet.
Cratis kanekoi sp. nov.
Cratis ohashii sp. nov.
Limopsoidea? gen. and sp. indet.
Brachidontes sp. indet.
Septifer sp. indet.
Crenella sp. indet.
Dacrydium zebra sp. nov.
Urumella concava gen. sp. nov.
Malleus (Malvufundus) sp. indet.
Parvamussium crypticum sp. nov.
Parvamussium decoratum sp. nov.
Cyclopecten ryukyuensis sp. nov.
Chlamydella incubata sp. nov.
Chlamydella tenuissima sp. nov.
Pycnodonte (Pycnodonte) taniguchii Hayami and Kase
Lima sp. indet.
Divarilima elegans sp. nov.
Ctenoides minimus sp. nov.
Isolimea limopsis (Nomura and Zinbo)
Limatula kinjoi sp. nov.
Limaria sp. indet.
Epicodakia pygmaea sp. nov.
Cardita uruma sp. nov.
Cardita sp. indet.
Carditella iejimensis sp. nov.
Carditella shimojiensis sp. nov.
Salaputium unicum sp. nov.
Rochefortina sandwichensis (Smith)
Kelliella japonica sp. nov.
Coralliophaga hyalina sp. nov.
Glossocardia obesa (Reeve)
Irus (Irus) sp. indet.
Irus (Notirus) sp. indet.
Hiatella sp. aff. H. orientalis (Yokoyama)
Halonympha asiatica sp. nov.
General Features of Cave Bivalves
1. Recognition of cryptic bivalves
2. Biased composition of taxonomic groups
3. Stunting of the cave bivalves
4. Species diversity and biomass
5. Affinities with deep-water faunas
6. Paedomorphosis by progenesis
7. Dominance of non-planktotrophic development
8. Dominance of K-selection
9. Fossil records of the cavernicolous bivalves
10. Origin and adaptation of cavernicolous bivalves
Conclusion
Acknowledgments
References




Itaru HAYAMI
Geological Institute, University of Tokyo
Tomoki KASE
National Science Museum




Index page