English  |  正體中文  |  简体中文  |  Items with full text/Total items : 28611/40652
Visitors : 772869      Online Users : 63
RC Version 4.0 © Powered By DSPACE, MIT. Enhanced by NTU Library IR team.
Scope Adv. Search

Please use this identifier to cite or link to this item: http://ntour.ntou.edu.tw:8080/ir/handle/987654321/46279

Title: Distribution, adult morphology and larval development of Sacculina sinensis Boschma 1933 (Cirripedia: Rhizocephala: Kentrogonida) in Hong Kong.
Authors: Benny Kwok Kan Chan;David Yiu Nam Poon;Graham Walker
Contributors: 國立臺灣海洋大學:海洋生物研究所
Date: 2005
Issue Date: 2018-05-14T06:31:11Z
Publisher: Journal of Crustacean Biology
Abstract: Abstract: Sacculina sinensis (Cirripedia: Rhizocephala) is a parasitic barnacle first reported in Hong Kong by Boschma (1933) to infect the intertidal crab, Leptodius exaratus. Since then, no studies have been conducted to investigate its distribution and morphology, which are important in providing background information for further taxonomic and ecological studies. In the present study, S. sinensis has shown to have a limited distribution in Hong Kong, being confined to only four out of the nine sheltered boulder shores sampled and with a mean infestation rate of

percent. The localized distribution of S. sinensis in Hong Kong is probably due to its short larval development times (four naupliar stages and one cypris stage, completed in about six days) and hence limited larval dispersal distance. The externa of S. sinensis is ovoid in shape with two distinct shoulders, and the outer cuticle surface is spinous. From histological studies, the male receptacles are located posteriorly in the visceral mass, and each male receptacle is globular in shape. The receptacle duct is folded and connected to the receptacle via a small tube with a thick cuticle lining. The larval morphology of S. sinensis was investigated using a scanning electron microscope. The appendages bear setulate setae in all naupliar stages. In the cyprid, segment III of the antennule consists of the attachment disc in both sexes, and the male has a large posterior aesthetasc which is absent in females. On segment IV, male cyprids have a large terminal aesthetasc, a subterminal aesthetasc, and three terminal setae. Segment IV of female cyprids has a subterminal aesthetasc which is smaller than that on the male cyprids. The larval sex ratio showed seasonal variation with 100 percent males in summer and 80 percent females in winter. Such seasonal variation in sex ratio would allow the female cyprids to infest the host crabs in winter, producing virgin externae by summer for the male cyprids to settle, and allow the externae to mature.
Relation: 25(1) pp.1-10
URI: http://ntour.ntou.edu.tw:8080/ir/handle/987654321/46279
Appears in Collections:[海洋生物研究所] 期刊論文

Files in This Item:

File Description SizeFormat

All items in NTOUR are protected by copyright, with all rights reserved.


著作權政策宣告: 本網站之內容為國立臺灣海洋大學所收錄之機構典藏,無償提供學術研究與公眾教育等公益性使用,請合理使用本網站之內容,以尊重著作權人之權益。
網站維護: 海大圖資處 圖書系統組
DSpace Software Copyright © 2002-2004  MIT &  Hewlett-Packard  /   Enhanced by   NTU Library IR team Copyright ©   - Feedback