Journal 
Introduction
Testate amoebae are a polyphyletic protozoan group which has a test. This group includes mainly Arcellinida (Amoebozoa) and Euglyphida (Cercozoa), but also it includes other minor groups of protozoans. This group can be further differentiated based on types of pseudopodia and shell materials (Ogden and Hedley 1980).
Testate amoebae are present in a wide range of moist and freshwater environments such as moss, soil, peat, standing water, etc. As testate amoebae can be identified according to their remaining shells even after death, they are useful in evaluating condition of freshwater ecosystem and wetland habitats (Booth 2002). They, therefore, have been used as quantitative proxy for hydrological changes related with climate or human activities (Lamentowicz et al. 2013).
Faunal studies on testate amoebae from Korea have been performed by several researchers (Chung and Choi 1989, 1995; Chung and Cha 1990; Chung and Kang 1991; Chung et al. 1992). As a result, thirty-three species of freshwater testate amoebae have been reported in this country. But many species are still remaining to be discovered. Here I report seventeen unrecorded species of testate amoebae collected from Korea.
Materials and Methods
Specimens used in this study were sampled from several locations in Korea. Water plants, water moss (Sphagnum) or benthic sediments were collected to sample testate amoebae. Specimens were sorted using an inverted microscope, AE2000 (Motic, Hong Kong). Then each specimen was mounted on a hole slide glass using Canada balsam media. A research microscope, BX53 (Olympus, Tokyo, Japan) was used to observe and take picture of specimens. All the specimens are deposited in Nation Institute of Biological Resources (NIBR), Incheon, Korea.
Results and Discussion
Phylum Amoebozoa Lühe, 1913
Subphylum Lobosa Carpenter, 1861
Class Tubulinea Smirnov et al., 2005
Order Arcellinida Kent, 1880
Family Arcellidae Ehrenberg, 1843
Genus Arcella Ehrenberg, 1832
1.Arcella arenaria Greeff, 1866 (Fig. 1A)
Material examined. 1 individual (KOSPIV0000241730): Korea, Jeju-do, Seogwipo-si, Saikdal-dong, The 1100-meter Hill wetland, 33°21′29.27″N, 126°27′47.36″E, 4 July 2015, collected by Jongwoo Jung.
Diagnosis. Shell brown, circular; hemispherical in lateral view. Aperture slightly invaginated, circular, bordered by a lip. Shell always circular in apical view, more or less domeshaped in lateral view; dorsal surface usually with slight folds, but very often flattened. Shell yellowish brown. Aperture small, circular in shape, its diameter barely reaching 1/5~1/6 that of the shell. Many small pores, 8~28 in number, around the aperture. Height of the shell not less than 1/2 diameter of the shell.
Habitat.Sphagnum.
World distribution. Northern hemisphere.
2.Arcella costata Ehrenberg, 1848 (Fig. 1B)
Material examined. 1 individual (KOSPIV0000241731): Korea, Jeju-do, Seogwipo-si, Namwon-eup, Soomang-ri, Mulyeongarioreum, 33°22′08.26″N, 126°41′35.30″E, 3 July 2015 (J. Jung).
Diagnosis. Shell in side view slightly trapezoid, with a flat polygonal top; aperture slightly invaginated, circular and bordered by a collar.
Habitat. Water plants.
World distribution. Cosmopolitan.
3.Arcella hemisphaerica Perty, 1852 (Fig. 1C)
Material examined. Twenty individuals (KOSPIV000024 1732): Korea, Gyeonggi-do, Paju-si, Jori-eup, Janggok-ri, Baekmagyo Br., 37°45′45.92″N, 126°51′20.39″E, 27 June 2015, collected by Jongwoo Jung; 1 individual: Korea, Jejudo, Seogwipo-si, Saikdal-dong, The 1100-meter Hill wetland, 33°21′29.27″N, 126°27′47.36″E, 4 July 2015 (J. Jung).
Diagnosis. Shell brown, circular; hemispherical in lateral view. Shell surface either smooth or with depressions giving the test an undulate appearance. Aperture slightly invaginated, circular, bordered by a lip.
Habitat. Water plants.
World distribution. Cosmopolitan.
Family Centropyxidae Jung, 1942
Genus Centropyxis Stein, 1857
4.Centropyxis constricta (Ehrenberg, 1843) (Fig. 1D)
Material examined. 1 individual (KOSPIV0000241733): Korea, Jeollanam-do, Sinan-gun, Heuksan-myeon, Ye-ri, 36°68′97.52″N, 125°45′45.31″E, 21 September 2015 (Hann Kim).
Diagnosis. Shell yellow, ovoid; aboral region in lateral view spherical but slightly tapering towards the aperture; shell usually smooth on the apertural surface and rough at the aboral region; aperture invaginated, oval with semi-circular apertural rim.
Habitat. Water plants.
World distribution. Cosmopolitan.
5.Centropyxis discoides Penard, 1890 (Fig. 1E)
Material examined. Twenty individuals (KOSPIV000024 1734): Korea, Gyeonggi-do, Paju-si, Jori-eup, Janggok-ri, Janggokgyo Br., 37°45′06.61″N, 126°50′29.59″E, 11 June 2015 (J. Jung).
Diagnosis. Shell brown, circular; discoid in lateral view. Small spines from lateral margin.
Remarks. Variation in presence and absence of spines was reported. The specimen observed has spines.
Habitat. Water plants.
World distribution. Cosmopolitan.
6.Centropyxis spinosa Cash, 1905 (Fig. 1F)
Material examined. 2 individuals (KOSPIV0000241735): Korea, Jeju-do, Seogwipo-si, Seongsan-eup, Onpyeong-ri, Honinji Pond, 33°24′54.74″N, 126°53′37.48″E, 4 July 2015 (J. Jung).
Diagnosis. Shell brown, circular with six lateral spines; lateral view spherical but slightly tapering towards the aperture; shell surface usually rough, and covered with sand grains, but area around aperture smooth; aperture invaginated, oval.
Habitat. Water plants.
World distribution. Cosmopolitan.
Family Difflugiidae Wallich, 1864
Genus Difflugia Leclerc, 1815
7.Difflugia amphora (Leidy, 1874) (Fig. 1G)
Material examined. 1 individual (KOSPIV0000241736): Korea, Jeju-do, Seogwipo-si, Saikdal-dong, The 1100-meter Hill wetland, 33°21′29.27″N, 126°27′47.36″E, 4 July 2015 (J. Jung).
Diagnosis. Shell brown, ovoid, circular in cross-section; fundus rounded aperture surrounded by shallow undulating lip.
Habitat. Bottom sediments of ditches and lakes.
World distribution. Cosmopolitan.
8.Difflugia globulosa Dujardin, 1937
Material examined. 1 individual (KOSPIV0000241737): Korea, Jeju-do, Seogwipo-si, Seongsan-eup, Onpyeong-ri, Honinji Pond, 33°24′54.74″N, 126°53′37.48″E, 4 July 2015 (J. Jung).
Diagnosis. Shell brown, spherical, rough; aperture circular, surrounded by smaller particles.
Habitat. Bottom sediments of ditches and lakes.
World distribution. Cosmopolitan.
9.Difflugia longicollis Gassowsky, 1936 (Fig. 1H)
Material examined. 1 individual (KOSPIV0000241738): Korea, Jeollanam-do, Sinan-gun, Heuksan-myeon, Ye-ri, 36° 68′97.52″N, 125°45′45.31″E, 21 September 2015 (J. Jung).
Diagnosis. Shell yellowish brown, pyriform, rough; fundus rounded; neck tapering evenly to the aperture; aperture circular, surrounded by smaller particles.
Habitat. Bottom sediments of ditches and lakes.
World distribution. Northern hemisphere.
10.Difflugia penardi Hopkinson, 1909 (Fig. 1I)
Material examined. 1 individual (KOSPIV0000241739): Korea, Jeju-do, Seogwipo-si, Andeok-myeon, Gamsan-ri, Andeok Valley 33°15′25.04″N, 126°21′12.23″E, 2 July 2015 (J. Jung).
Diagnosis. Shell transparent, ovoid, circular in transverse section; aperture small and circular.
Habitat. Bottom sediments of ditches and lakes.
World distribution. Cosmopolitan.
Family Heleoperidae Jung, 1942
Genus Heleopera Leidy, 1879
11.Heleopera rosea Penard, 1890 (Fig. 1J)
Material examined. 1 individual (KOSPIV0000241740): Korea, Jeju-do, Seogwipo-si, Andeok-myeon, Gamsan-ri, Andeok Valley, 33°15′25.04″N, 126°21′12.23″E, 2 July 2015, collected by Jongwoo Jung; 1 Individual: Korea, Jeju-do, Seogwipo-si, Saikdal-dong, The 1100-meter Hill wetland, 33°21′29.27″N, 126°27′47.36″E, 4 July 2015 (J. Jung).
Diagnosis. Shell lightly red, ovoid laterally flattened; aperture terminal, angular in outline, having thin, linear slit.
Habitat.Sphagnum and water plants.
World distribution. Cosmopolitan.
Family Hyalospheniidae Schulze, 1877
Genus Hyalosphenia Stein, 1857
12.Hyalosphenia subflava Cash and Hopkinson, 1909
Material examined. 1 individual (KOSPIV0000241849): Korea, Gyeonggi-do, Paju-si, Jori-eup, Janggok-ri, Baekmagyo Br., 37°45′45.92″N, 126°51′20.39″E, 27 June 2015 (J. Jung).
Diagnosis. Shell colourless, ovoid, smooth; elliptical in narrow view; oval in apertural view. Aperture terminal, oval or circular.
Habitat. Water plants.
World distribution. Cosmopolitan.
Family Nebelidae Taranek, 1882
Genus Nebela Leidy, 1874
13.Nebela militaris Penard, 1890 (Fig. 1K)
Material examined. 2 individuals (KOSPIV0000241850): Korea, Jeju-do, Seogwipo-si, Namwon-eup, Soomang-ri, Mulyeongarioreum, 33°22′08.26″N, 126°41′35.30″E, 3 July 2015 (J. Jung).
Diagnosis. Shell colourless, ovoid with a convex aperture in broad view, slightly compressed laterally, composed of a mixture of oval, circular and rectangular shell plates; aper ture elongate, surrounded by a thick organic collar.
Remarks. Specimens observed show variation in shell breadth.
Habitat. Water plants.
World distribution. Cosmopolitan.
14.Nebela penardiana Deflandre, 1936 (Fig. 1L)
Material examined. 1 individual (KOSPIV0000241851): Korea, Jeju-do, Seogwipo-si, Namwon-eup, Soomang-ri, Mulyeongarioreum, 33°22′08.26″N, 126°41′35.30″E, 3 July 2015 (J. Jung).
Diagnosis. Shell pale brown, pyriform; aperture oval, surrounded by a collar of organic cement.
Habitat. Water plants.
World distribution. Cosmopolitan.
Family Lesquereusiidae Jung, 1942
Genus Netzelia Ogden, 1979
15.N etzelia wailesi (Ogden, 1980) Meisterfeld, 1984 (Fig. 1M, N)
Material examined. 2 individuals (KOSPIV0000241852): Korea, Gyeonggi-do, Paju-si, Jori-eup, Janggok-ri, Baekmagyo Br., 37°45′45.92″N, 126°51′20.39″E, 27 June 2015 (J. Jung).
Diagnosis. Test ovoid to nearly globular. Protuberance not clear. Aperture irregular.
Habitat. Water plants.
Phylum Cercozoa
Subphylum Monadofilosa Cavalier-Smith, 1997
Class Imbricatea Cavalier-Smith, 1997
Order Euglyphida Copeland, 1956
Family Cyphoderiidae de Saedeleer, 1934
Genus Cyphoderia Schlumberger, 1845
16.Cyphoderia ampulla (Ehrenberg, 1840) (Fig. 1O)
Material examined. 1 individual (KOSPIV0000241853): Korea, Gyeonggi-do, Paju-si, Wollong-myun, Donae-ri, Juwolgyo Br., 37°48′02.14″N, 126°49′09.70″E, 27 June 2015 (J. Jung).
Diagnosis. Shell colorless, retort-shaped, circular in transverse section; shell plates siliceous, circular, bi-convex, arranged in diagonal rows; aperture circular, surrounded by a row of shell plates.
Habitat. Water plants.
World distribution. Cosmopolitan.
17.Cyphoderia trochus Penard, 1899 (Fig. 1P)
Material examined. 1 individual (KOSPIV0000241854): Korea, Gyeonggi-do, Paju-si, Wollong-myun, Donae-ri, Juwolgyo Br., 37°48′02.14″N, 126°49′09.70″E, 27 June 2015, collected by Jongwoo Jung; 1 individual: Korea, Jeju-do, Seogwipo-si, Saikdal-dong, The 1100-meter Hill wetland, 33°21′29.27″N, 126°27′47.36″E, 4 July 2015 (J. Jung).
Diagnosis. Shell colorless, retort-shaped, circular in transverse section; shell plates siliceous, circular, bi-convex, arranged in diagonal rows; aperture circular, surrounded by a ring of shell-plates.
Habitat. Water plants.
World distribution. Europe, South America.
