Ref ID : 3066
Sudzuki Minoru; [On the General Structure and the Seasonal Occurrence of the Males in Some Japanese Rotifers III.]. Zoological Magazine (Dobutsugaku Zasshi) 64(6):189-193, 1955
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This paper deals with the general structure and the seasonal occurrence of the males in three species of rotifers occurring in the same habitats as mentioned in my previous paper ('50, Zool.Mag. 64. 4). 10) Brachionus (Schizocerca) diversicornis (Daday): This species is a summer stenothermal form. Monocyclic. The Male-Female females appeared in the beginning of September. Total length 122 µm, body length 78-87 µm, width 44-48 µm. Lorica 52-62 µm in length, 44-48 µm in width. The structure of males as well as females of the present species is closely allied to that of Brachionus-species, so that Schizocerca need not be regarded as a distinct genus. 11) Asplanchna priodonta Gosse: The present species is rather perennial. The mictic females occurred in M1 from the end of June to the end of July and appeared again in the end of November. This species, therefore, is considered to be dicyclic. In addition to the relation among three types of females, namely, Female-Female, Male-Female and D-Female, both kinds of mictic eggs (cf. Lehmensick, '26) were recognized in the uterus of the same mother on April 21, and, further, mictic eggs were found in the same uterus on July 8. In the latter case, female-producing one was situated on the lateral side of excretory organ. Body 235-295 µm long, 120-132 µm wide. 12) Pedalia mira (Hudson): All specimens of the species were collected from M1. A monocyclic summer form. The males occurred from the middle of August to the end of September. Body length 27-48 µm, width 27-40 µm. The cloacal copulation has never been observed, but the male often attaches itself to the female at her head.