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On March 11th, 2011 the Mw 9.0 2011 Tohoku-Oki earthquake resulted in a tsunami which caused major devastation in coastal areas. Along the Japanese NE coast, tsunami waves reached maximum run-ups of 40 m, and travelled kilometers inland. Whereas devastation was clearly visible on land, underwater impact is much more difficult to assess. Here, we report unexpected results obtained during a research cruise targeting the seafloor off Shimokita (NE Japan), shortly (five months) after the disaster. The geography of the studied area is characterized by smooth coastline and a gradually descending shelf slope. Although high-energy tsunami waves caused major sediment reworking in shallow-water environments, investigated shelf ecosystems were characterized by surprisingly high benthic diversity and showed no evidence of mass mortality. Conversely, just beyond the shelf break, the benthic ecosystem was dominated by a low-diversity, opportunistic fauna indicating ongoing colonization of massive sand-bed deposits.

The present study describes the distribution patterns of the early life stages of pelagic cephalopods in three different areas of the Arabian Sea, Indian Ocean. Specimens were collected during the Meteor-expedition to the Indian Ocean in 1987 by means of multiple opening/closing nets in the top 150m of the water column. A total of 3836 specimens were caught at 67 stations. The following taxa were prevailing: Sthenoteuthis oualaniensis (Ommastrephidae), Abralia marisarabica and Abraliopsis lineata (Enoploteuthidae), Onychoteuthis banksi (Onychoteuthidae), and Liocranchia reinhardti (Cranchiidae). While the enoploteuthid species dominated the two neritic regions (the stations grids off Oman and Pakistan), the ommastrephid and cranchiid species were most abundant in the oceanic waters of the central Arabian Sea. The geographical and vertical distribution patterns of the taxa were analyzed and are discussed along with hydro graphic features which characterized the different areas. The data provide new and important information on the spawning areas of pelagic tropical cephalopods

Idiosepius thailandicus n. sp. is characterized in having' two rows of tentacle suckers and only 3-4 suckers on the hectocotylized arm (Arms IV of the male). It is a common neritic cephalopod along the coast of the Gulf of Thailand.

The enoploteuthid cephalopod Abraliopsis lineata is re-described and its generic position discussed. Specimens for the present study were captured during the Indian Ocean Expedition of RV Meteor in 1987, where the species occurred in considerable numbers. The geographical distribution of A. lineata is described and discussed. The detailed analysis of the photophore pattern of the present specimens differs from the original description. The diagnostic features in the male, especially the structure of the hectocotylus which separates A. lineata easily from the members of the subgenus Pfefferiteuthis, are outlined. The morphological differences which separate A. lineata from A. gilchristi, the only other member of the subgenus Micrabralia, are summarized.

General biology of cephalopods is described. First, all commercially important cephalopods are classified and the general morphology and distribution of all major families is described in detail. Mating and spawning characteristics of all major families are discussed in detail. This is followed by a discussion on early life history, growth and principal ecoological changes that occur during the growth period. Schooling and migration characteristics are also taken up in considerable detail. The paper closes with a brief discussion on the trophic relation. The author points out that cephalopods are extremely important to mankind due to their unique position in the food chain extending from the oceans to man.