Oryzias latipes, (TEMMINCK & SCHLEGEL, 1846)

Parenti, Lynne R., 2008, A phylogenetic analysis and taxonomic revision of ricefishes, Oryzias and relatives (Beloniformes, Adrianichthyidae), Zoological Journal of the Linnean Society 154 (3), pp. 494-610 : 550-553

ORYZIAS LATIPES ( TEMMINCK & SCHLEGEL, 1846)

MEDAKA

FIGURE 37

Poecilia latipes Temminck & Schlegel, 1846: 224 , pl. 102, fig. 5 [type locality: Japan, Nagasaki].- Boeseman, 1947: 167–168 [characters, lectotype designation].

Haplochilus latipes .- Günther, 1866: 311 [Nagasaki]. Aplocheilus latipes .- Jordan & Snyder, 1901: 57 [checklist, Yokohama, Japan].

Oryzias latipes .- Jordan & Snyder, 1906: 289–290 [ Poecilia latipes Temminck & Schlegel as type species of new genus, Oryzias ].- Oshima, 1919: 256–257 [report from Taiwan, characters].- Oshima, 1926: 1–25 [comparison with Oryzias from Hainan Is.].- Jordan & Tanaka, 1927: 264 [report from Amami- Oshima and Okinawa, Japan].- Smith, 1938: 166 [classification, characters].- Briggs & Egami, 1959: 363–380 [annotated bibliography].- Magnuson, 1962: 313 [reproductive biology; behaviour].- Rosen & Bailey, 1963: fig. 3c [skull].- Iwai, 1964: 31 [neuromast structure].- Rosen, 1964: 227 [classification in family Oryziatidae ].- Wiley & Collette, 1970: 190 [contact organs]. - Arai, 1973: 173 [chromosomes].- Satoh & Egami, 1972: 385–394 [sex differentiation of germ cells].- Ali & Lindsey, 1974: 959–976 [heritable and temperature-induced meristic variation].- Egami & Yamamoto, 1975: 276–365 [bibliography].- Yamamoto, 1975 [biology, comparisons].- Grier, 1976: 419–431 [testis structure].- Schrey, 1978: 335 [taxonomy of Oryzias ].- Hensley & Courtenay, 1980: 490 [status of introduced population in New York].- Sakaizumi et al., 1980 [genetic differentiation of populations in Japan].- Sakaizumi et al., 1983 [genetic differentiation of populations in Japan].- Liu, 1984: 418–419 [characters; report from Fujian Prov.].- Sakaizumi, 1984: 795–800 [genetic differentiation of northern and southern Japanese populations].- Iwamatsu et al., 1984b: 653–663 [hybridization with O. celebensis ; characters].- Sakaizumi, 1985: 521–522 [electrophoretic comparisons].- Uwa, 1985a: 3 [photograph of live specimens; distribution].- Uwa, 1986: 867–875 [cytogenetic comparisons].- Langille & Hall, 1987 [developmental osteology].- Parenti, 1987: 561 [characters; comparisons].- Sakaizumi & Jeon, 1987: 13–20 [allozyme divergence among Korean populations].- Uwa & Jeon, 1987: 139–147 [karyotypes of Korean populations].- Langille & Hall, 1988 [development of neural crest].- Uwa & Parenti, 1988: 159 [morphometric and cytogenetic comparisons].- Zhang, 1989: 295–296 [report from Pearl R., China].- Chen et al., 1990: 171–172 [distribution in Qiantang R., China].- Zhang, 1990: 219–220 [distribution in Shanghai region].- Fujita, 1990: 343 [caudal skeleton].- Fujita, 1992: 107–109 [caudal skeleton ontogeny].- Iwamatsu, 1993 [biology, comparisons].- Ishikawa, 1994: 17–24 [lateral line innervation].- Iwamatsu, 1994: 825–839 [stages of normal development].- Zhou, 1994: 494–496 [distribution in Sichuan Prov.].- Coad, 1995: 25 [listed from Iran as an introduction].- Hamaguchi, 1996: 757–763 [description and comparison of testis structure].- Seegers, 1997: 19, 20 [photographs].- Roberts, 1998: 221 [characters; relationships].- Yuma, Hosoya & Nagata, 1998: 111, 122 [distribution in Japan].- Anken & Bourrat, 1998: 1–92 [brain atlas].- Albert et al., 1999: 650 [brain weight].- Fuller et al., 1999: 285–286 [status of introduced populations in the United States].- Hosoya, 2000: 135–139 [conservation status in Japan].- Ishikawa, 2000: 487–495 [model system for vertebrate developmental genetics].- Matsuura, Doi & Shinohara, 2000: 189–192 [distribution in Japan].- Matsuura et al., 2000: 64 [reported as an endangered species living in a moat of the Imperial Palace, Tokyo].- Winn et al., 2000 [detection of mutations in transgenic individuals].- Naruse et al., 2000 [genome size]- Parenti, 2000b: 600 [listed].- Teather, Boswell & Gray, 2000: 813–818 [early life-history parameters].- Tatsuzawa, Sakaizumi & Kano, 2001: 89 [report from Mage-Shima Island, Japan, as a possible introduction; conservation status].- Kim & Park, 2002: 300 [ Korea].- Youn, 2002: 219 [ Korea].- Jang, Lucas & Joo, 2003: 119 [distribution in South Korean national parks].- Matsuda et al., 2003: 159–161 [genetics of sex determination and comparison with O. curvinotus ].- Parenti & Grier, 2004: 336 [atherinomorph testis type, listed].- Takehana et al., 2005: 417–428 [phylogenetic relationships inferred from molecules].- Kasahara et al., 2007: 714–718 [draft genome].

Oryzias latipes latipes .- Chen et al., 1989: 239–246 [comparisons with O. latipes sinensis ].- Uwa, 1991a: 361–367 [karyology, relationships].- Seegers, 1997: 15 [listed].- Sakai, Sato & Nakamura, 2001: 89–90 [conservation status; listed from Ryukyus, Japan].- Wittbrodt et al., 2002: 53–64 [status as model organism].

Differential diagnosis: Oryzias latipes is a member of the biarmed chromosome group of Uwa (1986), along with O. luzonensis , O. curvinotus and the miniatures O. sinensis and O. mekongensis , that have anal-fin rays of approximately the same length, forming a ‘parallelogram-shaped’ fin (as opposed to a subtriangular-shaped fin that tapers posteriorly) and chromosome arms numbering 58 or more (as opposed to 48 or fewer). Oryzias latipes and O. luzonensis are the largest species of this group that also share a mesethmoid ossification that is indented anteriorly in some specimens, and a genome size of 1.9 pg per nucleus or greater. They are like O. curvinotus and differ from the two miniatures by having the first pleural rib on the third, rather than the second, vertebra in most specimens, and paired, bilaterally asymmetric, as opposed to single lobed, testes. They are like the miniatures, and differ from Oryzias curvinotus by having bony processes on the pectoral-fin rays. Oryzias latipes has a dorsal fin that is posterior (opposite vertebrae 22–23 as opposed to vertebrae 20–21) and an ethmoid margin that is straight, rather than irregular, relative to O. luzonensis . Chromosome arm number is reported as 68 in O. latipes from southern Japan and 70 from northern Japan, and 96 in O. luzonensis ( Table 2).

Description: Small, maximum size of specimens examined 35.6 mm SL. Body compressed laterally, body depth 19–24. No pronounced abdominal concavity between pelvic fins and anal fin. Mouth terminal, jaws subequal or lower jaw projecting slightly beyond upper jaw. Dorsal body profile relatively straight from head to dorsal-fin origin; ventral body profile somewhat convex from head to anal-fin origin. Dorsal surface of head slightly convex just anterior to orbits. Head length 25–27 [25]; snout length 5–7; eye moderate, 8–9, orbits do not project beyond dorsal surface of head. Basal portion of dorsal and anal fin does not project significantly beyond primary body profile. Scales relatively large, cycloid; 28–32 [31] in a lateral series. Elongate, filamentous dorsal- and anal-fin rays in males; medial pectoral-fin rays and posterior analfin rays with large, bony contact organs. Medialmost pelvic-fin ray connected to body via a membrane along its proximal portion. Pelvic-fin rays of some female specimens elongate, nearly meeting anal-fin origin. Caudal fin truncate. Males with a short, tubular urogenital papilla; females with enlarged, slightly bilobed urogenital papilla.

Premaxilla short and broad with distinct ascending process; premaxilla and dentary with two irregular rows of caniniform teeth; males with two or three enlarged posterior teeth on the premaxilla and dentary; tooth tips project through lips. No preethmoid cartilage; ossified portions of mesethmoid discshaped; anterior border of ethmoid cartilage straight. No flanges on the ventral surface of the palatine and the quadrate. Dorsal ramus of hyomandibula not distinctly bifid, single cartilage articulates with sphenotic and pterotic. Lacrimal sensory canal carried in open bony groove. First pleural rib on parapophysis of third vertebra, rarely second; first epipleural bone attaches to parapophysis of first vertebra dorsal to, and not in horizontal line with, posterior epipleural bones; lateral process of pelvic bone attaches to fourth pleural rib. Caudal skeleton with two epural bones; one ventral accessory bone and one accessory cartilage. Fifth ceratobranchial toothplates subtriangular, with teeth in irregular rows anteriorly, followed by six discrete rows of unicuspid teeth, including a small, incomplete posterior row. Basihyal bone relatively short and triangular, basihyal cartilage extremely elongate and rectangular. Epibranchial elements fully ossified; epibranchial two notably smaller than the other epibranchial elements.

Dorsal-fin rays 5–7 [6]. Anal-fin rays 17–22. Pelvicfin rays 5–7 [6]. Pectoral-fin rays 9–11. Principal caudal-fin rays i,4/5,i. Procurrent fin-rays, dorsal 5, ventral 6. Vertebrae 27–32 (11–13 + 17–20). Branchiostegal rays 5–6.

Cytogenetic data: Oryzias latipes is a highly variable species with a biarmed chromosome constitution ( Table 2). Populations from southern Japan are reported to have 48 diploid chromosomes, including two metacentric, eight submetacentric, one subtelocentric and 13 acrocentric pairs. There are no populations with large metacentrics. Chromosome arm number (NF) totals 68 in populations from southern Japan and Korea and 70 from northern Japan.

Colour in life: Body translucent, and with melanophore pattern as described below in alcohol. Females with a subrectangular, males with a smaller, subtriangular silvery peritoneum and both sexes with a silvery operculum. Caudal fin with yellowish dorsal and ventral submarginal band in some populations.

Colour in alcohol: A diffuse to discrete row of melanophores from the dorsal surface of the head to the dorsal-fin origin, a midlateral black line from the head to base of the caudal fin that continues onto the caudal fin on the membrane just dorsal and ventral to the first ray above and below the midline, respectively. Females with a subrectangular, males with a smaller, subtriangular black peritoneum. A faint to discrete black line along the anal-fin base. Dorsal and anal fin interradial membranes with scattered melanophores. Specimens examined from Korea are dark brown above the midline; each dorsal scale is nearly filled with brown pigment.

Distribution and habitat: Widely distributed throughout eastern China, Hong Kong and Hainan Is., east Korea, the Japanese Archipelago from Honshu Island to the Ryukyu Islands in fresh to brackish water habitats (see Uwa & Parenti, 1988; Matsuura et al., 2000: 189) and Laos ( Roberts, 1998). The type locality of Poecilia latipes Temminck & Schlegel, 1846 is Nagasaki, Kyushu Is., southern Japan. Identification of Chinese and Laotian populations requires further study. Some of the material referred to here as O. latipes may be re-identified as O. sinensis . The Chinese specimens referred here to O. sinensis are miniature by the definition adopted here, not reaching more than 26 mm SL. The Laotian specimens are not miniature, reaching a reported 31.3 mm SL. Furthermore, the Laotian specimens have the first pleural rib on the third, not the second, vertebra, agreeing with O. latipes , not O. sinensis . Reports of O. latipes from localities throughout China (e.g. Zhang, 1990, Shanghai) may be of specimens referable to O. sinensis .

Remarks: Morphometric and meristic data are supplemented by those in Boeseman (1947), Iwamatsu et al. (1982), Iwamatsu (1986) and Uwa & Parenti (1988).

Jordan & Snyders’ (1906: 289) diagnosis of the genus Oryzias includes an illustration of a specimen of Oryzias latipes that is approximately 41 mm TL, or 33 mm SL. They also state that many specimens were collected at Wakanoura and Kawatana in 1900. One large collection of O. latipes, CAS-SU 9866, from Wakanoura, includes a 32.5-mm SL specimen in a vial with a label that reads ‘drawn’. I conclude that this is the specimen illustrated by Jordan & Snyder (1906).

Some local common names for O. latipes in Japan are tayu (in Amami-Oshima) and takami or takamigua (in Okinawa; Jordan & Tanaka, 1927: 264). Another common name for O. latipes in English is the Japanese ricefish, and, in Chinese, qing jiang yu (J. Song, pers. comm., 2004).

Material examined: 1321 specimens (7.5–35.6 mm SL).

Lectotype of Poecilia latipes . JAPAN. RMNH 2713 a, 1

(35 mm), designated by Boeseman (1947: 168).

Paralectotypes of Poecilia latipes . JAPAN: RMNH

2713b, 1 (33 mm), RMNH 2713c, 1 (31 mm), RMNH

2714a–c, 3, (24–31 mm).

Non-type specimens. JAPAN. HONSHU IS.: Aomori

Pref., Aomori, CAS 58021, 4 (28.2–30.0 mm), M .

Sakaizumi, viii.1979.

Aichi Pref., Nagoya, Kichi R., AMNH 26760, 44 (16.5–26.7 mm, 6 of which have been cleared and counterstained, 10 of which have been cleared and stained solely with alizarin), USNM 152491, 38 (18.5– 29.1 mm), D. S. Jordan, 1922.

Iwate Pref., Ichinoseki, CAS-SU 20123, 1 (26.5 mm), D. S. Jordan & J. O. Snyder.

Fukui Pref: Lake Ichinoseki, Mikato-cho , Mikatagun , CAS 56259, 2 (21.7–30.0 mm), 20.iv.1978 .

Nagano Pref., Suwa , CAS 58024, 77 (16.5– 22.6 mm), W. Magtoon & H. Uwa, 9.viii.1985 .

Ibaraki Pref., Lake Kasumigaura, USNM 152514, 7 (19.5–27 mm), K. Hattori, 1922.

Shiga Pref., Lake Biwa Aquarium, Ohtsu City , CAS 57464, 7 (juveniles, 5 of which have been cleared and counterstained, 1 of which was removed for histological preparation), pres. 1.x.1985, CAS 57465, 8 (2.5–8.5 mm) .

Kyoto Pref., Isazu R., Maizuru City , CAS 56258, 1 (28.5 mm), 15.vii.1974 .

Miyagi Pref., Shiuhara (= Shiogama?) CAS-SU 23865, 2 (19.0–28.0 mm, both specimens dehydrated), FMNH 55559, 6 (21–27 mm), D. S. Jordan; Shiogama Rikuzen, USNM 71305, 36 (16.7–30.6 mm), J. O. Snyder & M. Smith, 1938.

Ishikawa Pref., Nanao, ricefields, USNM 71188, 20 (11.5–34.2 mm), D. S. Jordan, J. O. Snyder & M. Sindo, 20.vii.1906.

Wakayama Pref., Kii Suido, Wakanoura, CAS-SU 9866 , 101 (18.8–32.5 mm; one specimen, 32.5 mm, in vial with label that reads ‘drawn’), BMNH (1923.2.26: 160–169, 97 (18–34 mm), USNM 62334 , 31 (19.4– 29.5 mm), D.S. Jordan & J. O. Snyder, possibly 1900.

Shimane Pref., Oki Is., Saigo, USNM 71195, 48 (16.5–35.0 mm), D. S. Jordan, J. O. Snyder & M. Sindo, vii.1906.

KYUSHU IS.: Kagoshima Pref.; Kagoshimawan, CAS-SU 24663, 1 (18.5 mm), Akune, Satsuma, USNM 70779, 254 (13.5–33.5 mm, 2 of which have been cleared and counterstained), J. O. Snyder & M. Smith, 1938.

Nagasaki Pref., Iki Is., Tasou R., Ashibe-cho, CAS 56257, 4 (16.6–24.9 mm), 2.viii.1976, Kawatana , CAS-SU 20125 , 77 (12.2–35.6 mm, 3 of which have been cleared and counterstained), D. S. Jordan & J. O. Snyder .

RYUKYU ISLANDS, OKINAWA IS.: Okinawa Pref., southern half of island, CAS 54866, 4 (18.3– 26.1 mm), T. D. White,. vii.1947 , CAS-SU 23664 , 5 (13.5–18.0 mm), H. Kuroiwa, Tingan , USNM 164237 , 6 (13–30 mm), Hanashito, 25.ii.1954 .

CHINA. Shandong (Shantung) Prov.: Jinan (Tsinan), Da Ming Hu, ANSP 51944 , 6 (16.0– 18.0 mm), A. P. Jacot, 1.x.1926, ANSP 51950 , 1 (7.5 mm), A. P. Jacot, 21.xi.1924; North Gardens in rice and lotus fields, ANSP 51951 , 2 (19.0–21.0 mm), A. P. Jacot, autumn 1927–1928 (field no. APJ27-NG- F). Jinan (Tsinan), BMNH 1928.1.16: 4–6, 5 (17– 20 mm), E. Hindle .

Beijing Prov., Xinan, USNM 337323 , 20 (17– 25 mm), ex. ASIZB 44193 ; Huairou, Huairou Reservoir , boat launch at observatory, USNM 337325 , 1 (24.2 mm), L. R. Parenti & C.-G. Zhang, 24.iii.1995 .

Gansu Prov., upper Huang He (Yellow R.), ASIZB 52348, 6.

Hebei Prov., outside Beijing: Yenching University , USNM 89214 , 5 (12.3–15 mm, distorted), Y. Ching, 1.vii.1928 , AMNH 14469 , 3 (23.3–26.5 mm), Reinke, viii.1927 .

Shanxi Prov., lower Huang He (Yellow R.), ASIZB 42666, 7.

Guangxi (Kwangsi) Autonomous Region, Wo Chow , CAS-SU 30247 , 56 (12.5–25.0 mm), A. W. Herre, 14.ii.1934 .

Zhejiang (Chekieng) Prov., Zhoushan (Choushan) Is., CAS-SU 32587 , 84 (13.5–23.7 mm), CAS-SU 68377 , 1 (15.9 mm), A. W. Herre, 2.x.1936 .

Fujian (Fukien) Prov., Gangken , CAS-SU 39569 , 1 (25 mm), J. L. Gressitt, 25.vii.1936 . Among (Gi-Mei), USNM 336717 , 2 (25.5–27 mm), 9.ix.1963 . SFU uncat, 5 (20–27 mm), 9.vii.1963 .

SOUTH KOREA. Busan ( Fusan ), USNM 45266 , 37 (24–33 mm), P. Jouy, 28 May 1886 , Masan, small rocky creek 1.25 mi S of Masan, USNM 163873 , 3 (29–31 mm), R. MacEwan , 4.vii.1951 , near Chayo (35°17′08″N, 128°42′54″W), USNM 162685 , 6 (18– 26 mm), V. G. Springer , 11.iv.1952 ; Kyongsangnamdo: Ulsan-shi, Song’am-dong, Ch’ongniang R., eastern Korean drainage emptying into Sea of Japan, CAS 60708, 15 (25.9–28.9 mm), S.- R. Jeon , 29.xi.1986 , laboratory specimens fixed 7.vii.1987.

TAIWAN. Kizanto : ANSP 76433 , 28 (20–30.5 mm), M. Oshima, 9.iv.1917 (field no. MO17-K-4–9), CAS-SU 23166 , 9 (24.4–31.5 mm), M. Oshima; Taiko, CAS-SU 23115 , 5 (12.2–21 mm), M. Oshima .

LAOS. Nam Theun watershed : ricepaddy near Tha Bac, CAS 92323, 125 (14.6–29.6 mm, 9 of which, 16.0– 24.3 mm, have been cleared and stained solely with alizarin), T. R. Roberts & P. Vongsay, 20.xi.1995 ; roadside ditches and paddy on road from Laksao to Tha Bac, CAS 92324, 2 (27.7–31.3 mm), T. R. Roberts, 8–17 Jun 1995 .

Figures

Figure 37. Oryzias latipes (Temminck & Schlegel, 1846), Kagoshima Prefecture, Japan, USNM 70779, male, 28.2 mm SL.