Japanese Freshwater Planarians in Color
(Dr. M. Kawakatsu)

Last update: 30-DEC-2002


By Gen-yu SASAKI (gen-yu@mtc.biglobe.ne.jp)

The taxonomy and distributional ecology of Japanese freshwater planarians ("Turbellaria": Seriata: Tricladida) have been studied by Dr. M. Kawakatsu and his team members for the past 50 years. In 1969, he published an illustrated list of this animal group with distribution maps and water color paintings of the 19 known species at that time (2 families and 6 genera; including 2 unidentified species of the genus Sphalloplana).

After the 1970s', 5 native species and 3 exotic species have been described and reported by Kawakatsu and his coauthors from Japan. The taxonomic system from the rank of suborder through infraorder, family, subfamily, genus, and subgenus was revised in 1974.

In the present web article a revised list of all the known species of Japanese freshwater planarians is given with their latest Linnean names and Japanese names (see Notes for the Taxonomic List) in the Roman alphabet (1 suborder, 2 infraorders, 4 families, 2 subfamilies, 8 genera, 1 subgenus, 27 species; including 2 undescribed species). Dr. Kawakatsu's (1969) original 2 color plates are also reproduced herein; no paintings of 8 species described after 1970 are included (see the mark "-" in the Taxonomic List).

Notes for the Taxonomic List

In Japan both Japanese and Linnean names of animals (and plants) are employed in usual biology books and encyclopedias. For this custom a complehensive explanation is given in the following English article.

The infraorder Cavernicola Sluys, 1990 (including 1 family and 5 genera), was established in the following publication.

Japanese Freshwater Planarians: Taxonomy

("Turbellaria": Seriata: Tricladida): mainly based on Kawakatsu, 1998.

Dugesiidae Ball, 1974 (SANKAKUATAMA-UZUMUSHI KA*)
Dugesia Girard, 1850 (NAMI-UZUMUSHI ZOKU)
Dugesia japonica Ichikawa et Kawakatsu, 1964Nami-uzumushi1a, b.
D. ryukyuensis Kawakatsu, 1976Ryukyu-nami-uzumushi-
[R]D. izuensis Kato, 1943Izu-uzumishi2.
[ET]D. austroasiatica Kawakatsu, 1985Toonan-ajia-uzumushi(*) -
Girardia Ball, 1974 (AMERICA-NAMI-UZUMUSHI ZOKU**)
[ET]Girardia tigrina (Girard, 1850)America-nami-uzumushi-
Planariidae Stimpson, 1857 (HIRATA-UZUMUSHI KA*)
Phagocata Leidy, 1847 (HOSO-UZUMUSHI ZOKU)
Phagocata vivida (Ijima et Kaburaki, 1916) Miyama-uzumushi3.
Ph. kawakatsui Okugawa, 1956Kogata-uzumushi4.
Ph. teshirogii Ichikawa et Kawakatsu, 1962Toohoku-kogata-uzumushi5.
Ph. iwamai Ichikawa et Kawakatsu, 1962Ezo-kogata-uzumushi6.
[R]Ph. papillifera (Ijima et Kaburaki, 1916) Kantoo-ido-uzumushi7.
Ph. albata Ichikawa et Kawakatsu, 1962Sooya-ido-uzumushi8.
Ph. tenella Ichikawa et Kawakatsu, 1963Hidaka-hoso-uzumushi9.
Ph. suginoi Kawakatsu, 1974Hokuriku-hoso-uzumushi-
Polycelis Ehrenberg, 1831 (KAZUME-UZUMUSHI ZOKU)
Polycelis (Polycelis) sapporo (Ijima et Kaburaki, 1916) Kitashiro-kazume-uzumushi12.
Seidlia Zabusov, 1911 (KITA-KAZUME-UZUMUSHI ZOKU**)
Seidlia auriculata (Ijima et Kaburaki, 1916)Kazume-uzumushi10.
S. schmidti (Zabusov, 1916)Kita-kazume-uzumushi11.
S. akkeshi (Ichikawa et Kawakatsu, 1963)Akkeshi-kazume-uzumushi13.
Dendrocoelidae Hallez, 1892 (OO-UZUMUSHI KA*)
Kenkiinae Hyman, 1937 (HORA'ANA-UZUMUSHI AKA*)
Sphalloplana de Beauchamp, 1931 (HORA'ANA-UZUMUSHI ZOKU)
Sphalloplana sp.1Yautsugadake-izumi-uzumushi14.
Sphalloplana sp.2Himeji-menashi-uzumushi15a, b.
Dendrocoelinae Hallez, 1892 (OO-UZUMUSHI AKA*)
Bdellocephala de Man, 1875 (OO-UZUMUSHI ZOKU)
Bdellocephala annandalei Ijima et Kaburaki, 1916Biwa-oo-uzumushi16.
B. brunnea Ijima et Kaburaki, 1916Izumi-oo-uzumushi17.
B. borealis Kawakatsu, 1978Rishiri-oo-uzumushi-
Dendrocoelopsis Kenk, 1930 (KITA-OO-UZUMUSHI ZOKU)
Dendrocoelopsis ezensis Ichikawa et Okugawa, 1958 Ezo-uzumushi18.
Den. lactea Ichikawa et Okugawa, 1958Kitashiro-uzumushi19.
Den. ichikawai Kawakatsu, 1977Rishiri-uzumushi-
[R] Den. kishidai Kawakatsu, 1978Kyoto-uzumushi-

Dimarcusidae Mitchell et Kawakatsu, 1972 (MEXICO-CHIKASUI-UZUMUSHI KA**)
Rhodax Marcus, 1946 (BRAZIL-UZUMUSHI ZOKU**)
[ET]Rhodax? sp.Brazil-uzumushi(*)-

In the taxonomic list the figures of 8 species with a mark "-" are not presented in this web article.
[R]: Rare species listed in Kawakatsu (1991); [ET]: Exotic species in Japan; *: A new Japanese name was given by Kawakatsu (1998); **: A new Japanese name was given in this web article in cooperation with Dr. Kawakatsu.
The right-side numbers (1-19) given in the taxonomic list are correspond to the number of figures of animals in the next 2 plates (VII and VIII).

Plate VII

Kawakatsu, 1969: Plate VII

Dugesia japonica: 1a. The Matsumoto stock (sexual race). 1b. The Kyûshû stock (asexual race).

Plate VIII

Kawakatsu, 1969: Plate VIII

Sphalloplana sp. 2: 15a. The Himeji stock. 15b. Adhesive organ (an enlarged, ventral view of the head).

Order and Suborders of Japanese Planarians ("Turbellaria")

So-called "planarians" in a narrow sense indicate macroscopic flatworms in the order Tricladida. In a wide sense, however, that word means a general, collective name of animals in a few orders (and suborders) of the class "Turbellaria". The order Polycladida is a large group of marine planarians.

The following tabular list is a summary of the taxa and their numbers listed in a Japanese paper published by Kawakatsu (1998). His list includes flatworms of 8 orders, 20 families, 93 species, and 3 subspecies. According to Dr. Kawakatsu that list was prepared as basic data for the compilation of the Japanese Red Data Book of Endangered Species: The Invertebrates (First Ed., 1991; see the References in the previous section of this web article).

Prorhynchida1f. 2spp.
TRICLADIDA7f. 57spp.
Maricola (=Retrobursalia)Marine planarians1f. 5spp.
Paludicola (=Probursalia)Freshwater planarians3f. 27spp.
TerricolaLand planarians3f. 25spp.
Dalyellioida1f. 10spp.
Typhloplanoida1f. 8spp.
Kalyptorhynchia2f. 2spp.

Kawakatsu's (1998) list of "Turbellarians" includes macroscopic, freshwater and terrestrial species and only a single marine triclad, Ectoplana limuli (Ijima et Kaburaki, 1916), an ectoparasitic species of the Japanese helmet crab (Tachypleus tridentatus). This probably results from T. tridentatus approaching beaches at spring tide to lay their eggs in the sand.

In this list, Rhodax? sp. in the Cavernicola is placed in the Paludicola. Additionally, the class "Turbellaria" is now considered a non-monophyletic group.


Sasaki, the compiler of this web article, wishes to express his hearty thanks to Dr. Masaharu Kawakatsu (Sapporo, Japan) for his kind permission for the opening of this home page mainly based upon his papers as well as for his careful reading and suggestions in an early draft. The compiler is also indebted to Dr. Robert W. Mitchell (Bandera, Texas, U.S.A.) for his kind reading and corrections of English usage in the final draft.


  1. Kawakatsu, M. 1968. An illustrated list of Japanese freshwater planarians. Collect. and Breed. (Saishu-to-Shi'iku), Tokyo, 30 (2): 40-45. (In Japanese.)
  2. Kawakatsu, M. 1969. An illustrated list of Japanese freshwater planarians in color. Bull. Fuji Women's College, (7), Ser. II: 45-91 (+ pls. VII-VIII).
  3. Kawakatsu, M. 1973. Taxonomy and ecology of planarians, 1 and 2. The Nature and Animals (Doubutsu-to-Sizen), Tokyo, 3 (5): prefatory page; (6): 11-16. (In Japanese.)
  4. Kawakatsu, M. 1991. Entry in the Japanese Red Data Book: Ectoplana limuli (Ijima et Kaburaki, 1916), Dugesia izuensis Kato, 1943, Pahagocata papillifera (Ijima et Kaburaki, 1916), and Dendrocoelopsis kishidai Kawakatsu, 1978. In: Environmental Agency of the Prime Minister's Office (ed.), "The Japanese Endangered Species, Invertebrates Other than Insects", pp. 233, 241, 249, 259. The Research Center of Wild Animals and Plants in Japan, Tokyo. (In Japanese.)
  5. Kawakatsu, M. 1998. Plathelminthes: Turbellaria. In: Environmental Agency of the Prime Minister's Office (ed.), "A list of Japanese Wild Species of Plants and Animals: Invertebrates III", Chapt. 42. pp.19-22. (In Japanese.)

Additions and Corrections

(December 30, 2002)

This web article was opened in public on May 5, 2001. According to a suggestion of Dr. Kawakatsu, it becomes clear that some additions and corrections to the present article are necessary.

Maricola:2f. 2sf.6g. 7spp
Paludicola: 3f. 2sf. 8g. 27spp.
Terricola:3f. 3sf.7g. 15spp. ( +12 "unidentifiable" spp. including species inquirendae)
Cavernicola:1f.1g. 1sp.
(f = family; sf = subfamily; g = genus)

Since: 05-MAY-2001