• The Korean Journal of Zoology
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• v.35 no.4
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• pp.484-488
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• 1992

Three species of Archaeogastropoda were found new to the fauna of Korea, and are described in this paper. These include Emarginulo crossicostato Sowerby, 1863, Collisello cassis (Eschscholtz, 18331, and Collonista umakusaensis Habe, 1950. As the result, the Korean marine Archaeogastropod fauna comprises 10 families, 67 species and 9 subspecies.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.10a
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• pp.247-248
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• 2002

원시복족목 (Archaeogastropoda) 밤고둥과 (Trochidae)에 속하는 서해비단고둥(Umbonium thomasi)은 우리나라의 서해안과 중국연안에만 서식한다. 비단고둥 (U. costatum)보다 소형으로 낮은 원추형이고, 조간대의 모래사장에 살며 간조 때에는 모래 속으로 파고 들어간다. 껍질은 약간 푸르스름하고 꾸불꾸불한 회색 무되가 방사상으로 덮여 있으며 내부는 진주층으로 광택이 있다 (Yoo, 1976; Kwon et al., 1993). (중략)

• Animal Systematics, Evolution and Diversity
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• no.nspc3
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• pp.23-28
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• 1992

Two new subspecies of Gastropoda, Scelidotoma vadososinuata hoonsooi(Archaeogastropoda) and Buccinum mirandum koreanum (Neogastropoda) are reported in this paper.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.6
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• pp.702-708
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• 2002

Although Umboniunm thomasi is one of marine mollusc (Archaeogastropoda: Trochidae) inhabiting the sands in the intertidal zone of the west coast of Korea, aspects of its reproductive biology are still not too well known. Reproductive cycle, gametogenesis, and first sexual maturity of U. thomasi collected at the west coast of Buan-gun, Jeollabuk-do, Korea were investigated monthly from January to December 1999. U. thomasi was dioecious, and an oviparous. The gonad was placed in the rear of the flesh part in the spiral shell. The external colors of the ripe ovary and testis appeared to be green and milk-white or yellowish white, respectively. Meat weigh rate peaked in July ($37.5\%$). And then the value sharply decreased in September ($28.3\%$), thereafter, gradually increased in November ($31.7\%$). Fully ripe oocytes were approximately 100$\~$110 $/mu$m in diameter, and their cytoplasm contained a great number of yolk Branules. Based on the monthly changes of the Bonadal development, gametogenesis, and meat weight rate, the reproductive cycle of U. thomasi could be devided into five successive stages: early active (November to April), late active (February to May), ripe (April to August), spawning (July to October), and recovery (September to February). Gonadal development and spawning were closely related to the seawater temperature, the main spawning occurred in September when the temperature reached above 24.2$^{\circ}C$. Individuals of 4.4 mm and less in shell height could not take part in reproduction in both sexes. Percentages of first sexual maturity of female and male shells ranging from 5.5 to 6.4 mm were $55.0\%$ and $61.9\%$, respectively, and $100\%$ of those over 7.5 mm in shell heights in both sexes participated in the reproduction.