Minidiscus, a New Recorded Nanodiatom Genus for China

Gao Ya-Hui, Cheng Zhao-Di, Jin De-Xiang (T. G. Chin)

Received:1900-01-01 Revised:1900-01-01 Online:1992-05-18 Published:1992-05-18
Contact: Gao Ya-Hui

Abstract:

Minidiscus trioculatus, M. comicus and M. chilensis are new records for China, and

M. subtilis, is a new species. They differ from Thalassiosira species by their strutted processes

and one single labiate process being distant from valve margin and they differ from each oth-

er by their areola patterns on valves and distribution patterns of strutted processes and the

labiate process. A key to the species of Minidiscus is given.

Minidiscus subtilis Gao, Cheng et Chin sp. nov., figs 7-8

Valves disc-shaped, slightly concave in center, weakly silicified, 3.5-5.5μm in diameter.

Areola unequally radiate-striate, striae 8.5 / lμm. A narrow valve mantle without striae.

Three strutted processes and a single labiate process located in the central area of the valve.

Among them, one strutted process in the very center with the other two adjacent to it, form-

ing an isometric triangle with the labiate process between the two subcentral strutted pro-

cesses. Two small satellite pores in each base of the strutted processes. M. subtilis differs from

M. chilensis mainly by their radiate striae continuously distributed from the valve center to

the margin.

Key words: Minidiscus trioculatus, M. comicus, M. chilensis, M. subtilis

Gao Ya-Hui, Cheng Zhao-Di, Jin De-Xiang (T. G. Chin). Minidiscus, a New Recorded Nanodiatom Genus for China[J]. .

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