Two New Infusoria (Protozoa) from Iowa

Proceedings of the Iowa Academy of Science

Volume 38 Annual Issue Article 95

1931

Robert L. King State University of Iowa

Let us know how access to this document benefits ouy

Recommended Citation King, Robert L. (1931) "Two New Infusoria (Protozoa) from Iowa," Proceedings of the Iowa Academy of Science, 38(1), 241-243. Available at: https://scholarworks.uni.edu/pias/vol38/iss1/95

This Research is brought to you for free and open access by the Iowa Academy of Science at UNI ScholarWorks. It has been accepted for inclusion in Proceedings of the Iowa Academy of Science by an authorized editor of UNI ScholarWorks. For more information, please contact [email protected]. King: Two New Infusoria (Protozoa) from Iowa

TWO NEW INFUSORIA (PROTOZOA) FROM IOWA

Rom<;RT L. Krnc Thecacineta edmondsoni n. sp. (Fig. 1) Test truncated pyriform, widest at the base where it is fixed by a short stalk, truncated at the apical end where there is a definite, free, lip-like border; circular in cross section. Three or four corru gations at the widest part of the base. Body oval or spherical fastened to the base of the test, usually protruding from the test but not completely filling it. Tentacles slightly knobbed, numerous, scattered over the protruding surface of the body. Macronucleus central, oval; micronucleus not observed. One, two or three con •tractile vacuoles, requiring 12-20 minutes at 22° C. for a complete cycle. Size: Test, greatest diameter 40-50 µ, height 30-35 µ. Stalk 7-10 µ. Body 50-70 µ long and 30-40 µ wide. Tentacles 20-30 µ long. Food: Colpoda and other small ciliates. Found in a mixed cul ture of tap water and garden soil, Iowa City, Iowa, February, 1930. One single individual questionably belonging to this species observed in April, 1928, in a mixed soil and creek water culture at Philadelphia, Pa. This form is named for Charles Howard Edmondson whose work "The Protozoa of Iowa" represents the most important con tribution to our knowledge of this group in the state. Thecacineta edmondsoni differs from T. solenophryaformis (Sand) in the shape of the test, its corrugations at the base, its definitely turned lip, its shorter stalk and the distribution of tentacles. Individuals of this new species were observed which showed what might be considered as stages in binary fission but which have been called teratological forms by Collin. One pair in con jugation has also been observed; the union of the individuals tak ing place by the approximation of the orifices of their respective tests. According to Collin there are four genera of Suctoria which have a test with a free border. Two of these Solenophrya and Thecacineta represent a series of forms that may be separated by Published by UNI ScholarWorks, 1931241 1 Proceedings of the Iowa Academy of Science, Vol. 38 [1931], No. 1, Art. 95 242 IOWA ACADEMY OF SCIENCE [VoL.XXXVIII

the presence of a stalk in the latter and its absenc~ in the former. For this reason only the form described here is placed in the latter genus. V orticella echina n. sp. (Fig. 2) Body urn shaped, enlarged medially, forming an elongated cone posteriorly. Surface of the body covered with spines except on the oral disc and base. Transversely striate at the base. Peristome slightly elevated, ciliary disc small. Contractile vacuole near the cytopharynx. Macronucleus long, band shaped, micronucleus not

Figures for two new Infusoria (Protozoa) from Iowa. Robert L. King, Iowa City https://scholarworks.uni.edu/pias/vol38/iss1/95 2 King: Two New Infusoria (Protozoa) from Iowa

1931] TWO NEW INFUSORIA (PROTOZOA) FROM IOWA 243

observed. Stalk contractile. Animal spherical when contracted (fig. 3) cysts (fig. 4) spherical, with short blunt spines. Size: Body 25-50 µ long, 20-35 µ wide. Stalk 70-100 µ long. Spines 10 µ long about 2 µ wide at base. Cysts 10-20 µ. Numerous specimens were found in a culture of green-house soil and pond water August, 1930, Iowa City, Iowa. This species is similar in form and size to V orticella micro~toma but differs from it in the presence of the long spines, which dif ferentiate this species from all others in the genus. Stages of nuclear reorganization have been found in the cysts (fig. 4).

STATE UNIVERSITY oF IowA, lowA CITY, low A.

Published by UNI ScholarWorks, 1931 3