• Animal cells and systems
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• 제5권1호
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• pp.37-44
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• 2001

Gonadal development, reproductive cycle, gonad index, meat weight rate, and first sexual maturity of the top shell, Omphalius rusticus were Investigated monthly by histological observations. Specimens were collected from the west coast of Korea during the period from January to December in 1999. O. rusticus is dioecious and oviparous. The gonad is widely situated on the surface of the digestive g1and located in the posterior spiral meat part in the shell. The ovary and the testis were composed of a number of oogenic follicles and several spermatogenic follicles, respectively. Ripe oocytes were approximately 120-130 $\mu$m in diameter. The meat weight rate peaked in June (27.7%), and then rapidly decreased in September (19.5%). Monthly changes in the gonad index in both sexes reached the maximum in June, and then sharply decreased in September. Percentages of first sexual maturity of female and male snails ranging from 9.0 to 9.9 mm in shell heights were 58.3% and 54.5%, respectively, and 100% in those over 11.0 mm in both sexes participated in reproduction. Reproductive cycle of this species can be categorized into five successive stages: in females, early active (October to April), late active (December to June), ripe (April to September), spawning (July to September) and recovery (September to January): in males, early active (November to March), late active (December to June), ripe (April to September), spawning (July to September) and recovery (September to December). Gonadal development, gametogenesis, reproductive cycle, and spawning were closely related to the seawater temperature.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2000년도 추계수산관련학회 공동학술대회발표요지집
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• pp.244-245
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• 2000

The top shell, Omphalius rusticus (Gastropoda: Trochidae), is marine mollusk inhabiting underneath a rock in the intertidal zone of the coasts of Korea and Japan, and it is one of the edible gastropods. This species is a herbivorous animal. Up to now, there have been some reports on the Trochidae: aspects of classification, spawning periodicity, production, growth and size-frequency distribution of living populations, feeding, reproductive cycle, and induction of larval metamorphosis. (omitted)

• 한국패류학회지
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• 제6권1호
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• pp.33-44
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• 1990

A study on the distribution and community structure of benthic molluscan shells of the northern coastal area in Cheju Island was carried out from July 1989 to June 1990. The benthic molluscan shells collected and identified were composed of 3 classes, 9 orders, 29 familes and 81 species. The first dominant species of the wpper intertidal zone of the northern coastal area in Cheju Island was Nodilittorina exigua and second dominant species were Heminerita japonica, Monodenta neritoides, Monodota neritoides, Littorina brevicula, those of middle intertidal zone were Lunella coronata coreensis, Monodonta neritoides and Omphalius rusticus. H. japonica, M. neritoides, O. rusticus, L. coronata coreensis and Niotha livescens were dominant in the lower intertidal zone, and Astralium haematragum was dominant in the infralittoral zone of within 60 feet sea water depth. The benthic molluscan standing biomass of intertidal and infralittoral zones were 145.71-705.55 gr/ /m sup 2 / and 84.57-1645.67 gr/m sup 2/ respectively, But thao among area and zones were apparently differences.

• 환경생물
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• 제30권2호
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• pp.143-150
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• 2012

독도 조간대 해양무척추동물의 공간적인 분포를 밝히기 위해서 2009년부터 2011년까지 10차례에 걸쳐 현장조사를 실시하였다. Bray-Curtis 유사도를 이용한 집괴분석을 통하여 3개의 군집을 밝혔으며, 첫 번째 군집은 자갈해변군집으로 이동성 복족류인 보말고둥과 깜장각시고둥 그리고 밤고둥이 우점종으로 나타났으며, 두 번째 군집은 잔잔한 암반해안으로 보말고둥, 큰뱀고둥 그리고 군소가 우점종으로 나타났으며, 마지막 군집은 두 종의 고착형 절지동물인 검은큰따개비와 거북손이 우점하는 것으로 나타났다. 이들 군집은 독도 암반조간대의 기질의 종류와 수리역학적인 조건에 의해 결정되었으며, 환경적인 조건이 해양생물의 생물다양성을 유지하고 증가시키는데 중요한 역할을 하는 것으로 보인다.