著者

大塚 攻 宮川 千裕 平野 勝士 近藤 裕介

出版者

日本動物分類学会

雑誌

タクサ:日本動物分類学会誌 (ISSN:13422367)

巻号頁・発行日

vol.45, pp.48-60, 2018-08-31 (Released:2018-08-31)

参考文献数

89

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Ecto- and meso-parasitic copepod basibionts harbor a wide variety of epibionts. The basibionts belong to the families Caligidae, Pandaridae, Trebiidae, Pennellidae, Sphyriidae, Bomolochidae, Ergasilidae, and Lernaeidae. Epibionts consist of bacteria, suctorian and peritrich ciliates, hydrozoan polyps, udonellid monogeneans, stalked barnacles, and algae. Udonellids and hydrozoan polyps seem to correspond to hyperparasitism, while attachment of some algae is regarded as accidental phoresy. These fish parasites provide unique substrates for epibionts, due to (1) no molting in the adults, (2) provision of relatively long-live and stable attachment sites, and (3) protection from fish immune responses, in addition to advantages of high mobility and dispersal of primary host fish.

著者

大塚 攻 平野 勝士 宮川 千裕 近藤 裕介 菅谷 恵美 中井 敏博 高田 健太郎 福島 英登 大場 裕一 三本木 至宏 浅川 学 西川 淳

出版者

日本プランクトン学会

雑誌

日本プランクトン学会報 (ISSN:03878961)

巻号頁・発行日

vol.66, no.2, pp.86-100, 2019-08-25 (Released:2019-09-03)

参考文献数

94

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In marine ecosystems, bacterial interactions with zooplankters are highly complex, and much attention has recently been given to these interactions. Bacteria not only play the role of food and symbionts for zooplankters, but also function as decomposers for their carcasses, exuviae and feces. Free-living bacteria are involved as major producers in microbial loops, and form the diet of nanoplanktonic flagellates, ciliates, appendicularians and thaliaceans. Epibiotic and enteric bacteria use zooplankters as refuges to avoid predation and/or as food sources. However, aggregations of epibiotic bacteria or biofilms may function as “a second skin,” sensu Wahl et al. (2012), to modulate hosts metabolism and behaviors. Because they contain rich nutrients, low pH and low oxygen, copepod guts provide a unique environment for bacteria in which anaerobes can survive. Bacterial communities on copepods vary seasonally and among species, depending on the physiology of the host. The conveyor-belt hypothesis implies that bacteria vertically, and presumably horizontally, hitchhike in different water masses in accordance with the migrations of zooplankters. Bioluminescent bacteria are likely used as biomarkers of detrital foods for some planktonic copepods belonging to the Bradfordian families and as obligate symbionts for bioluminescent ichthyoplankters. Tetrodotoxin-producing bacteria are associated with chaetognaths that may use toxins to capture prey animals. Colonial cyanobacteria provide substrata for miraciid harpacticoid copepods. Hyrdomedusae play a role as vectors of pathogenic bacteria, causing lesions in farmed fish. Modern genetic analysis is a powerful tool that will be the first step in revealing the physiological and functional interactions between bacteria and zooplankton.