The specimens of the five species/subspecies of Tanakia, eleven species/subspecies of Acheilognathus, and eleven species/subspecies of Rhodeus examined belong to the collection of The University Museum, The University of Tokyo (ZUMT), and The National Science Museum, Tokyo (NSMT). They are comprised of 15 species/subspecies from Japan, 12 species/subspecies from China, the only species from Korea, and one subspecies from Europe. Specimen number, standard length (SL), and localities of these are as follows:
- Tanakia himantegus chii (Miao) ZUMT k-187 and k-188, 2 specimens, 45.2-47.8 mm SL, from Qingpu, Shanghai, China
- Tanakia lanceolata (Temminck & Schlegel) ZUMT k-1 and k-2, 2 specimens, 66.3-69.5 mm SL, from Onjuku, Chiba Pref., Japan; ZUMT 59915, 1 specimen, 75.3 mm SL, from Kanzaki, Saga Pref., Japan; ZUMT k-226 and k-227, 2 specimens, 48.0-50.2 mm SL, from Fengcheng, Liaoning, China
- Tanakia limbata (Temminck & Schlegel) ZUMT k-5, k-6, and k-8, 3 specimens, 42.4-45.1 mm SL, from River Yabegawa, Fukuoka Pref., Japan
- Tanakia signifer (Berg) NSMT-P 46879, 1 specimen, 46.8 mm SL, from Chorwon, Kangwon-do, Korea
- Tanakia tanago (Tanaka) ZUMT 57468, 1 specimen, 42.0 mm SL, from River Isumigawa, Chiba Pref., Japan
- Acheilognathus cyanostigma Jordan & Fowler ZUMT k-182 and k-195, 2 specimens, 39.9-50.3 mm SL, from River Yodogawa system, Osaka, Japan
- Acheilognathus longipinnis Regan NSMT-P 27990, 2 specimens, 59.3-60.5 mm SL, from River Yodogawa system, Japan
- Acheilognathus macropterus (Bleeker) ZUMT 41677 and 42520, 2 specimens, 74.7-84.0 mm SL, China
- Acheilognathus melanogaster Bleeker ZUMT 59895-59897 and 59899, 4 specimens, 33.4-53.0 mm SL, from Lake Izunuma, Wakayanagi, Miyagi Pref., Japan
- Acheilognathus omeiensis (Shih & Tchang) ZUMT k-193 and k-194, 2 specimens, 55.5-66.8 mm SL, from Sichuan, China
- Acheilognathus rhombeus (Temminck & Schlegel) ZUMT 59913-59914, 2 specimens, 69.7-71.5 mm SL, from Kanzaki, River Chikugogawa, Saga Pref., Japan; ZUMT 59927, 1 specimen, 53.4 mm SL, from River Yabegawa, Fukuoka Pref., Japan
- Acheilognathus tabira tabira Jordan & Thompson ZUMT k-180 and k-181, 2 specimens, 69.4-73.4 mm SL, from Lake Biwa, Shiga Pref., Japan
- Acheilognathus tabira subsp. (a) (Japanese name: Akahire-tabira) ZUMT k-184 and k-185, 2 specimens, 48.8-60.9 mm SL, from Ami, Ibaraki Pref., Japan
- Acheilognathus tabira subsp. (b) (Japanese name: Seboshi-tabira) ZUMT 59928, 1 specimen, 48.8 mm SL, from River Yabegawa, Fukuoka Pref., Japan
- Acheilognathus typus (Bleeker) ZUMT 59906-59909, 4 specimens, 49.3-60.2 mm SL, from Lake Izunuma, Wakayanagi, Miyagi Pref., Japan
- Acheilognathus yamatsutae Mori ZUMT k-224 and k-225, 2 specimens, 49.6-52.5 mm SL, from Fengcheng, Liaoning, China
- Rhodeus atremius atremius (Jordan & Thompson) ZUMT 59917 and 59920, 2 specimens, 31.1-35.9 mm SL, from Kanzaki, River Chikugogawa, Japan
- Rhodeus atremius suigensis (Mori) ZUMT k-220 and k-221, 2 specimens, 30.9-33.8 mm SL, from Fengcheng, Liaoning, China; ZUMT 57469, 1 specimen, 36.8 mm SL, from River Asahigawa, Seto, Okayama Pref., Japan
- Rhodeus fangi (Miao) ZUMT k-192, 1 specimen, 27.1 mm SL, from Fenghua, Zhejiang, China; ZUMT k-250, 1 specimen, 30.5 mm SL, from Chongyang, Hubei, China
- Rhodeus haradai Arai, Suzuki & Shen ZUMT k-237, 1 specimen, 52.4 mm SL, from Hainan Island, China
- Rhodeus notatus Nichols ZUMT k-238 and k-239, 2 specimens, 35.9-37.1 mm SL, from Tieling, Liaoning, China
- Rhodeus ocellatus ocellatus (Kner) ZUMT 59888, 59891, and k-162, 3 specimens, 41.5-43.5 mm SL, from Lake Izunuma, Wakayanagi, Miyagi Pref., Japan
- Rhodeus ocellatus kurumeus Jordan & Thompson ZUMT 59916, 1 specimen, 41.1 mm SL, from Kanzaki, River Chikugogawa, Japan; ZUMT k-200, 1 specimen, 46.4 mm SL, from Osaka, Japan
- Rhodeus sericeus amarus (Bloch) NSMT-P 13754, 2 specimens, 46.3-52.1 mm SL, from Albina-Uliuc, Roumania
- Rhodeus sericeus sericeus (Pallas) 2 specimens, 41.6-57.2 mm SL, from Qingyuan, Liaoning, China
- Rhodeus sinensis Günther ZUMT k-189 and k-190, 2 specimens, 42.1-43.1 mm SL, from Qingpu, Shanghai, China; ZUMT k-222 and k-223, 2 specimens, 38.3-39.0 mm SL, from Fengcheng, Liaoning, China
- Rhodeus spinalis Oshima ZUMT k-236 and k-238, 2 specimens, 32.6-41.6 mm SL, from Hainan Island, China
As the canals of the lateral line system are formed comparatively late in ontogeny (Disler, 1971; Lekander, 1949), the specimens used for examination were only adult specimens which were identified by an ovipositor in the female and pearl organs on the head in the male. The sensory canals were prepared using the method of Kurawaka (1977) and Potthoff (1984). Illustrations were prepared using a camera lucida attachment on a Leica MZ-8 stereomicroscope. Sensory canal terminology except for the otic and postotic canals followed Coombs et al. (1988).
As the preopercular canal did not connect with the otic-postotic canal in all bitterlings, it was difficult to separate the otic canal from the postotic canal. Therefore, the temporal canal (= the otic canal + the postotic canal) defined by Lekander (1949) was adopted in this paper. Pore counts were made of the supraorbital, infraorbital, temporal, mandibular, preopercular, and supratemporal canals. Definition of the complete and incomplete trunk canals followed Coombs et al. (1988). Scale counts of the complete trunk canal represent the number of scales
on the trunk canal from the scales which contact the shoulder girdle to the scales on the posterior end of the hypural bone (Masuda et al., 1984). Scale counts in longitudinal scale rows were made similarly to that of the trunk canal scales in fishes without a trunk canal or with an interrupted trunk canal (Masuda et al., 1984). The infraorbital bone series consists of the lacrimal to dermosphenotic bones (Cavender & Coburn, 1992; Gosline, 1975).
Phylogenetic polarity of the cephalic sensory canal system, the infraorbital bones, and the trunk canal (the lateral line) was determined by mapping their character states on a molecular tree based on mitochondrial 12S ribosomal DNA sequences (Okazaki et al., 2001).
Generic classification of bitterlings followed Arai & Akai (1988). Akai & Aral (1998) synonymized R. lighti with R. sinensis. Classification of subfamilies followed Chen et al. (1984), except the Squaliobarbinae, which was separated from the Leuciscinae and corresponds to the squaliobarbine group by Howes (1981). As Cavender & Coburn (1992) divided the Leuciscinae into phoxinins (mainly North America) and leuciscins (mainly Eurasia), the Leuciscinae was divided into the Leuciscinae from North America and the Leuciscinae from Eurasia. The Danioninae was placed in the Rasborinae.
Abbreviations Used in Text and Figures
- IOC
- infraorbital canal
- MC
- mandibular canal
- PC
- preopercular canal
- SOC
- supraorbital canal
- STC
- supratemporal canal
- TC
- temporal canal
- TRC
- trunk canal
- an
- anterior nostril
- f
- frontal
- io
- infraorbital
- p
- parietal
- pn
- posterior nostril
- pt
- pterotic