Biol. Bull. Sign up for etocs!
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via ISI Web of Science (2)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Yamashita, K.
Right arrow Articles by Fusetani, N.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Yamashita, K.
Right arrow Articles by Fusetani, N.
Related Collections
Right arrow Behavior
Right arrow Cnidarians
Right arrow Development
Right arrow Larval Biology
Biol. Bull. 204: 256-269. (June 2003)
© 2003 Marine Biological Laboratory

Larval Behavioral, Morphological Changes, and Nematocyte Dynamics During Settlement of Actinulae of Tubularia mesembryanthemum, Allman 1871 (Hydrozoa: Tubulariidae)

Keiji Yamashita1, Satoru Kawaii2, Mitsuyo Nakai and Nobuhiro Fusetani3

Fusetani Biofouling Project, ERATO, JST (formerly Research & Development Corporation of Japan), Isogo-ku, Yokohama 235-0017, Japan

1 To whom correspondence should be addressed. Present address: Biofouling Group, Himeji EcoTech Co., Ltd., 841-49 Koh, Shirahama-cho, Himeji-shi, Hyogo 672-8023, Japan. E-mail: keiji-y{at}cb3.so-net.ne.jp

The marine colonial hydroid Tubularia mesembryanthemum produces a morphologically unique dispersive stage, the actinula larva. Detailed observations were made on the behaviors and nematocyte dynamics of actinula larvae during attachment and morphogenesis by employing microscopic and time lapse video techniques. These observations produced four primary results. (1) Actinula larvae demonstrated two forms of attachment: temporary attachment by atrichous isorhiza (AI)—nematocysts discharged from the aboral tentacle (AT) tips—and permanent settlement by cement secretion from the columnar gland cells of the basal protrusion. (2) During larval settlement, numerous AIs were discharged from the AT tips with sinuous movement and rubbing of the tentacles onto the substrata, leading to "nematocyte-printing" around the settlement site. (3) Simultaneous with the discharge of the AIs, migration of stenoteles, desmonemes, and microbasic mastigophores occurred, resulting in a dramatic change of nematocyte composition in the ATs after larval settlement. This was in parallel with changes in larval behavior and the tentacle function. (4) Nematocyte-printing behavior during settlement could be recognized as metamorphic behavior responsible for irreversible changes in AT function, from attachment to feeding and defense.

Abbreviations: AI, atrichous isorhiza • AT, aboral tentacle • D, desmosome • MM, microbasic mastigophore • S, stenotele






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 2003 by the Marine Biological Laboratory.