Japanese Journal of Ichthyology 魚 類 学 雑 誌 Vol.19,No.4 December 25,1972 19巻4号1972年12月25日

Variations of Spinal Curvature and Vertebral Number in

Hirotoshi Asano and Yoshikazu Kubo Received July 28,1972) (

Abstract The spinal curvature and the vertebral counts were investigated in fifteen races of the gold- fish(Carassius carassius auratus),as compared with five forms of the crucian carps.On the basis of the spinal curvature,the examined fishes were roughly classified into the following three groups. The first group with Kin-buna type curvature,which includes all forms of the crucian carps is characterized by having the abdominal vertebrae always located above the base line and the majority of the caudal vertebrae are situated bellow the line(the degree of spinal curvature is generally small in its value).The second group with Wakin type curvature,which includes five races of the gold- fish is closely related to the first group,but the degree of spinal curvature is comparatively large in its value.The third group with type curvature,which includes other ten races of the goldfish is characterized by the vertebral column always situated above the base line(the degree of spinal curvature shows comparatively larger value).The total vertebral counts show relatively high values in the crucian carps,while the counts are somewhat reduced in most of the goldfish. And also it is presumed that there exists a negative correlation between the degree of spinal curvature and the total number of vertebrae.

The goldfish is commonly believed to be Material and methods derived from the crucian carp,Carassius carassius auratus(Linnaeus),by artificial selec- The goldfish and the crucian carps examined tion,originally in China.In Japan,about in this investigation are as follows:the Wakin twenty or more races of the goldfish are (Jap),,,Jikin(Peacock- established for a long time(Matsui,1934). tail),Ryukin(Nymph),Tetsuonaga(Iron Those races of the goldfish have distinctive fringetail),( nymph),Aka- external features respectively,such as the demekin(Red telescope),Kuro-demekin(Black body form,the eye shape,the fin form,the telescope),Chotengan(Celestail),Sanshiki- coloration,etc.,although they show individual demekin(Calico telescope),-shishi- variations in some extent.With regard to gashira(Oranda),Azumanishiki(Calico the body form,they vary from the Wakin Oranda),(),Chinese Hana- (Jap)with a moderately slender body to the fusa(Red velvetyball),Kin-buna(Carassius Ranchu(Lionhead)with a short and round auratus subsp.),Nigoro-buna(C.auratus body.Such variations of the body form grandoculis Temminck and Schlegel),Gin- seem to be correlated with the curvation of buna(C.auratus langsdorfi Temminck and vertebral column and the number of vertebrae. Schlegel),Gengoro-buna(C.auratus cuvieri From such points of view,we investigated Temminck and Schlegel),and Kawachi-buna the curvation of vertebral column and the (the cultured form of the Gengoro-buna). vertebral number of fifteen races of the gold- Outline drawings of races of the goldfish and fish,comparing them with five forms of subspecies of the crucian carps(except for the crucian carps. Kawachi-buna)are shown in Fig.1.For the present study,we used specimens of normal

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Fig.1.The outline drawings of the examined races of the goldfish and subspecies of the crucian carps(except for Kawachi-buna).A,Kin-buna;B,Nigoro-buna;C,Gin-buna;D,Gengoro buna;E,Wakin(with simple caudal fin);F,Wakin(with trilobed caudal fin);G,Shubun kin;H,Comet;I,Jikin;J,Ryukin;K,Tetsuonaga;L,Calico;M,Aka-demekin;N,Kuro demekin;O,Chotengan;P,Sanshiki-demekin;Q,Oranda-shishigashira;R,Azumanishiki; S,Ranchu;T,Chinese Hanafusa. external appearance for each form,and those Vertebral number and degree of the curva- with extremely deformed vertebral column were tion of the vertebral column were examined avoided.The localities where samples were ob- on X-ray photographs in lateral view.The tained were as follows:the Gin-buna from the vertebral counts include the Weberian verte Ichigi River,Mie Pref.;the Gengoro-buna and brae,counted as four,and the urostylar ver the Kawachi-buna from the fishponds of the tebra,counted as one.Hereafter,instead of "the curvation of the vertebral column Osaka Prefectural Freshwater Fish Experiment ,"we Station in Neyagawa,Osaka Pref.;the Kin shall use"the spinal curvature,"the term used buna from Jonuma,Gunma Pref.;the Nigoro- by Ford(1937:14).In the present investi- buna from Lake Biwa,Shiga Pref.;the Jikin gation,the spinal curvature was indicated by from a fish culturist in Ise,Mie Pref.;and a curve traced on the X-ray photograph by other races of goldfish from several fish- joining the center of each centrum.The culturists in Koriyama,Nara Pref. specimens were preserved in 10%formalin in

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Table 1.The list of crucian carps and goldfish,with the number of samples,counts,and measure- ments of specimens.

*The value of the area restricted above the base line+the area restricted below the line =the sum of these two value. **The values in parentheses indicate the mean . their most natural posture so as to prevent Results twisting or bending. For the study of the spinal curvature,the Spinal curvature:Fig.2 indicates indivi- body axis(the tip of the snout to the center of dual variations of the spinal curvature in 4 the penultimate vertebra)was found un- specimens of the Jikin,against the body axis. suitable.The line drawn from the anterior In the case of the Jikin,the position of the end of the first vertebra to the posterior end first vertebra that is at the left end of each of the penultimate vertebra was mainly used curve varies considerably against the body as the base line for comparison of the spinal axis. curvature.To evaluate the degree of spinal Among 10 examined specimens of the curvature,we measured with the planimeter Jikin,5 had their first vertebra located above the area enclosed between the standardized the body axis,1 just on the line,and remaining base line of 20cm and the mean curve of 4 below the axis.In all specimens of this spinal curvature.The mean curve in each race,however,the posterior segment of the race of the goldfish and subspecies of the spinal curvature was located below the axis, crucian carps was drawn through connecting varying in its length from individual to indi- representative five points,each of which was vidual.Except for the Jikin,in all of the a mean of the intersecting points of curves of examined goldfish and crucian carps their individual specimen on each of five vertical anterior segments of the spinal curvatures are lines spaced at regular intervals on the base usually located above the axis and also their line. posterior segments are located above or,at

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Fig.2.Individual variations of the spinal curvature of the Jikin,against the body axis.An oblique dash on each curve indicates the boundary between abdominal and caudal vertebrae. The body length of four specimens are:1,10.4 cm,2,12.8 cm;3,10.1 cm;4,7.0 cm.

Fig.3.Variations of the spinal curvature(against the base line)of the examined fishes which are classified into three groups.A,Kin-buna type;B,Wakin type;C,Ryukin type.The numbers labeled to each curve corresponds to the number at the first column in Table 1. An oblique dash on each curve indicates the end of the abdominal vertebrae. most,on the axis.Thus,in the correlation of each form is also indicated in Table 1. between the spinal curvature and the body The first group,which has the Kin-buna axis,the Jikin alo ne is distinguished from type curvature,includes all examined crucian other forms. carps(Fig.3A).They are characteristic in The body axis,however,is unsuitable for having the abdominal vertebrae always located comparison of the spinal curvature,because above the base line,while the majority of the the length of the vertebral column varies from caudal vertebrae are situated below the line. individual to individual as shown in Fig.2. Moreover,the maximum distance of each Fig.3 indicates the mean spinal curvatures curve from the base line is smaller than that of goldfish and crucian carps,in relation to of the other two groups. Therefore, the the base line defined above.Each form had degree of spinal curvature is usually smaller its characteristic spinal curvature,as shown in in its value and is not so much different among Fig.3 A-C.The degree of spinal curvature five members of this group(Table 1).

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The second group,which has the Wakin from the base line.In the remainders the type curvature,includes the Wakin,Jikin, curves are similar and difficult to distinguish Shubunkin,Comet,and Azumanishiki(Fig. from each other.The races of the third 3B).As to the Wakin,we treated two subforms group had comparatively larger values of the separately,the Funao-shaped Wakin with a degree of spinal curvature,as compared with simple caudal fin and the Mitsuo-shaped forms of the above-mentioned two groups Wakin with a tri-lobed caudal fin.This type Table 1).The Chotengan has the smallest is closely related to the above-mentioned value in this group,while the Ranchu has Kin-buna type.In this group of fishes,the the largest value.The Chinese Hanafusa, anterior segment of the spinal curvature Sanshiki-demekin,Tetsuonaga,and Calico located above the base line is relatively longer have the smaller value for the members of and the maximum distance between each curve this group.Even in these races,the degrees and the base line is usually much larger than of spinal curvature are subequal to those of that of the Kin-buna type.Considerable the Mitsuo-shaped Wakin and Azumanishiki variations were observed among the races of of the Wakin type.The Ryukin has a large the second group.The spinal curvature of value which is next to the Ranchu.And. the Funao-shaped Wakin is very similar to other three races,the Oranda-shishigashira, that of Kin-buna type.On the contrary,in Kuro-demekin,and Aka-demekin,had mod the Azumanishiki the spinal curvature is rather erately large value,and intermediate between similar to the Ryukin type which will be the above-mentioned two extremities of the mentioned later.Between the Funao-shaped third group. Wakin and Mitsuo-shaped Wakin,there exists Vertebral counts:As shown in Table 1, a considerable difference:the latter has its the number of vertebrae considerably varies own curve which is rather similar to that of among the examined fishes and also individual- the Azumanishiki.In the Jikin and the ly to some extent.Fig.4 indicates the varia- Shubunkin,the spinal curvature resembles tion of the total vertebral counts and those of each other,and the curve is relatively similar the abdominal and caudal vertebrae.Here to that of the Funao-shaped Wakin.The those counts are expressed as the mean values Comet has its own curve intermediate be- for each race and form. tween the above-mentioned two extremities. In the case of the crucian carps(Fig.4:1-5), As shown in Table 1,the fish of this group had the total vertebrae are about 30-32 and com- the higher values of the degree of spinal paratively numerous.They are similar in. curvature than the fish of the Kin-buna type. their constitution of vertebral counts, having Among the members of this group,the Azuma- about 17-18 abdominal and about 13-14 nishiki has the largest value,while the Funao- caudal vertebrae.The Nigoro-buna was a shaped Wakin has the smallest value,and the exception in having about 1 less abdominal Mitsuo-shaped Wakin has its value much and about 1 or 2 more caudal vertebrae than larger than that of the Funao-shaped Wakin. the other crucian carps.Among the Wakin The third group,which had the Ryukin type goldfish,two subforms of the Wakin, type curvature,includes other ten goldfish, Shubunkin,and Comet(Fig.4,6 and 8 to 10) two-thirds of the examined races of the gold- had about 30 vertebrae in total. And also fish(Fig.3C).The most remarkable feature they had the abdominal and caudal vertebral of this type is that the whole vertebral column counts similar to the crucian carps.The is situated above the base line.Among the Mitsuo-shaped Wakin slightly differs from the members of this group, the chotengan has the Funao-shaped Wakin in having about 1 less curve with the smallest maximum distance and abdonimal vertebra. Most of the remaining, the Ranchu with the largest maximum distance goldfish have comparatively fewer vertebrae,

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totaling about 29.They are composed of about 16 abdominal and 13 caudal vertebrae in the former,and 15 abdominal and about 14 caudal ones in the latter.The Sanshiki-deme- kin,Calico,Kuro-demekin,and Ryukin had a similar constitution of vertebral counts, namely about 14 abdominal and 12-13 caudal vertebrae(Fig.4:14,16,19 and 20).Ac- cordingly,their total vertebral counts are reduced to about 26.In the Oranda-shishi- gashira,the vertebrae were reduced to about 24 in total,and composed of 13 abdominal and about 11 caudal vertebrae(Fig.4:17). The Ranchu had the fewest total vertebrae with about 12 abdominal and about 10 caudal vertebrae(Fig.4:21).In two remaining races,the Chinese Hanafusa and Tetsuonaga (Fig.4,13 and 15),number of caudal vertebrae was equal to or more than that of abdominal vertebrae,and unique among examined fishes. Fig.4.Variations of the total vertebral counts and the constitution of abdominal and caudal Especially in the specimen of the Tetsuonaga, vertebrae.Open circles,the Kin-buna type; the abdominal vertebrae were reduced to 13, crosses,the Wakin type;semi-open circles, while the caudal ones were 15. the Ryukin type.The numbers labeled to each mark correspond to the numbers at the rst column in Table 1. fi Discussion which is due to the diminution of the abdomi- As already mentioned above,the spinal nal and/or the caudal vertebral number.The curvature and vertebral counts of the goldfish constitution of abdominal and caudal verte- considerably vary among the examined races. bral counts largely varies from race to race. The races of goldfish are,however,different Of the second group(with Wakin type curva from crucian carps in the following points: ture),the Jikin and Azumanishiki(Fig.4:7 and (1)the spinal curvature is either the Wakin 11)are different from each other in the total type or Ryukin type;(2)the degree of spinal vertebral counts and the vertebral constitution, curvature is comparatively large in its value; and also from other members.In the case of and(3)the vertebral counts are somewhat the Jikin,the abdominal vertebral counts were reduced in most of the examined races. same with that of the Mitsuo-shaped Wakin, The degree of spinal curvature and the verte- but the caudal vertebral counts were about 2 bral counts have a negative correlation as a fewer than that of the Mitsuo-shaped Wakin; whole(the correlation coefficient:-0.8147), accordingly the total vertebral counts were as shown in Fig.5.Nevertheless,in the about 28.The Azumanishiki had the lowest correlation between these features,the Jinkin total vertebral counts of about 22,in the group and the Azumanishiki(Fig.5,7 and 11)of of this type,which was composed of 12 abdo- the second group with Wakin type spinal minal and about 10 caudal vertebrae. curvature seem to be different from the rest In the third group with Ryukin type curva- of the members of this group.In the Azuma- ture,the Chotengan and Aka-demekin(Fig. nishiki,emphasis was put on the situation of 4,12 and 18)had higher counts of vertebrae, the posterior segments of vertebral column,

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the body cavity is much larger and shorter than the slender bodied goldfish.In our examination of goldfish,the short bodied goldfish included all of the races of the Ryukin type(except for the Chotengan)and the Azumanishiki of the Wakin type.Their body cavity is larger and shorter than the slender bodied goldfish which includes the rest of the members examined.And the degree of spinal curvature of the former is comparatively large in the value as compared with the latter. In the goldfish,the form and size of the caudal fin largely vary from race to race(Fig. 1).Fraser-Brunner.(1931)reported that the proportion of the two lobes of the swim- bladder is correlating with the size of the caudal fin in the ,for the adjustment of the altered center of gravity. However,Kawamoto(1960)stated that the Fig.5.Correlation between the number of total vertebrae and the degree of spinal curvature. lobes of the swimbladder of the Ryukin are Three kinds of marks and the numbers labeled not always correlated with the altered center to each mark,are same as in Fig.4 and Table 1. of the body gravity.In our examination,it may be roughly said that the races of the when the race was grouped in the second goldfish with the simple caudal fin,such as group on the basis of the status of the spinal the Funao-shaped Wakin,Shubunkin,and curvature(Fig.3:11).However,when we Comet,had the smaller values of the degree of regarded the degree of the spinal curvature spinal curvature and the larger number of (Table 1),the number of vertebrae(Table 1) vertebrae,as compared with other races of and the constitution of vertebral counts(Fig. the goldfish with the complex tails,which will 4:11),the race was adequate to be included in be discussed later in relation to the genealogy. the third group(Ryukin type).The Jikin Among the goldfish,the structure of the which belongs to the second group showed a caudal skeleton that is specialized to support distinct constitution of vertebral counts(Fig. and operate the caudal fin,varies not only 4:7).The race was distinguished from all of from race to race but also individually(Matsui, other examined forms in having the curvations 1935). particularly correlated with the body axis In many races of the examined goldfish, (Fig.2).Furthermore,the race is provided the number of vertebrae largely varied from with a characteristic tetra-lobed caudal fin: individual to individual.It has been experi- each lobe is separated from others and is mentally proved that the change of tempera- situated vertically against the body axis(Fig. ture has effects on the number of vertebrae in 1:I). fishes,such as the Medaka, Oryzias latipes Kawamoto(1960)observed that in the (Temminck and Schlegel)(Lindsey and Ali, slender bodied goldfish(Wakin and Shubunkin) 1951)and the ninespine stickleback,Pungitius the body cavity is narrow and the swimbladder pungitius(Linnaeus)(Lindsey,1962):Un- is situated almost horizontally,and that in fortunately,we do not know the tempera- the short bodied goldfish(Ryukin),the swim- ture in which our examined specimens were bladder is inclined downward posteriorly and raised.It is remarkable,however,that the

―229 ― 魚類学雑誌 Japan.J.Ichthyol.19(4) December 25,1972 extreme variations of the vartebral number crucian carp);the Ryukin,Jikin,and Aka- can be observed in all of the hybrid races demekin,from the Wakin;the Oranda-shishi- with the complex tails,such as the Azuma- gashira and Tetsuonaga,from the Ryukin; nishiki,Calico,and Ranchu(Table 1). the Sanshiki-demekin,Kuro-demekin,and

Gosline(1971)stated that"the progressively Chotengan,from the Aka-demekin;and the increasing emphasis on caudal locomotion in Ranchu,from the Maruko.Excepting the teleostean evolution is associated with the Tetsuonaga,all races examined are character- istic in having fewer vertebral number in the general trend toward reduction in the number of vertebrae•cthe relatively stiff bodied, mean value than their respective ancestral tail-swinging higher teleosts often have 24 or forms,though the relation between the Ranchu fewer."The crucian carps have fewer number and the Maruko is uncertain because of the

of vertebrae among the Japanese cyprinid lack of data.In the Chinese Hanafusa,the fishes,(Nakamura,1969).In the goldfish, geneological relationship between the race and

though the matters are not quite similar to the Japanese goldfish is unknown,and it has the case of higher teleosts,the reduction of not been possible to prove the point discussed

the number of vertebrae seems to be favorable above. to the fish with the complex tail for tail-swing- Thus,the variations of the spinal curvature

ing. and the vertebral number of the goldfish seem Referring to the Matsui's diagram(1934)of to be correlated,in relation to their functions,

the genealogical relationship among the Japa- with the change of the body form of the races

nese goldfish,we regarded the status of spinal which were artificially selected from a number curvature and the variation of the vertebral of hybrids and mutants.However,as stated

number in the examined races about half of by Ford(1937),if a vertebral character is to total races of the Japanese goldfish.Firstly, be of any use in taxonomy or phylogeny,it

the Funao-shaped Wakin and Shubunkin are must show a reasonable degree of intraspecific

provided with the simple caudal fin which is constancy.In our examined goldfish,either the spinal curvature or the vertebral number genetically dominant character against the com- plex tail.The former is considered to be the somewhat varied from individual to individual, and their extent of variation was different from prototype of the goldfish and the latter to be the hybrid between the crucian carp and the race to race.Therefore,it may be unable to

Sanshiki-demekin.In these two races,the overrate these features in taxonomic and

spinal curvature and the constitution of phylogenetic importance.A general trend of vertebral counts are similar to the crusian variations in these features,however,among

carps.In the Comet which can be produced the examined fish could be traced.In the by crossing the crucian carp with the Ryukin present investigation,we have not examined the size and form of the vertebral elements, (Matsui,1935),these features can be also observed.Secondly,the Calico(Sanshiki- which were left for future investigations. demekin•~Ryukin)and the Azumanishiki (Sanshiki-demekin•~Oranda-shishigashira)are Acknowledgments the hybrid between two different races to the

goldfish.In these two races,the degree of We wish to express our appreciations to spinal curvature is intermediate of those of Dr.Yoshiichi Matsui,Professor of Kinki

their parents,and the vertebral counts are University,for his pertinent criticism and somewhat fewer in the mean value than those helpful advice.Thanks are also due to Mr.

of their parents.Thirdly,the following races Koichi Ueno and students of our university are considered to be the matants:the Wakin who helped us in collecting the samples.

to be a mutant derived from the Hibuna(red

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Literature cited Nakamura, M. 1969. Cyprinid fishes of Japan (Stu- dies on the life history of cyprinid fishes of Japan) . Ford, E. 1937. Vertebral variation in teleostean Res. Instl Nat. Res., Tokyo, ii+455 pp., 19 figs, fishes. J. Mar. Biol. Assoc. U. K. 22: 1-60, figs. 2 color pls., 149 pls. In Japanese. 1-8, pls. 1-16. Fraser-Brunner, A. 1931.Exhibition of specimens (Department of Fisheries, Faculty of Agriculture, demonstrating a correlation between the air-bladder Kinki University, Higashiosaka, Osaka, Japan) and caudal fin in the common goldfish,(Carrassius auratus). Proc. Zool. Soc. London.(not seen). キ ンギ ョの 品 種 間 に お け る脊 柱 の 彎 曲状 況 と脊 椎 骨数 Gosline, W. A. 1971. Functional morphology and classification of teleostean fishes. Univ. Press of の 変 異 に つ い て 浅 野 博 利 ・久 保 喜 計 Hawaii, Honolulu. ix+208 pp., 29 figs. キ ンギ ョ15品 種 と フナ5型 に つ い て,第1脊 椎 骨 と Kawamoto, N. K. 1960. On the form and size of 尾 端 部 よ り第2番 目の 脊 椎骨 とを結 ぶ 直線 を基 準 と し, the swimbladder of goldfish (Carassius auratus L .) 各 椎 体 中央 部 を通 る よ うに描 い た脊 柱 の彎 曲 状 況 を比較 in special reference to its body equilibrium. Rep. Fac. Fish., Pref. Univ. Mie, 3 (3): 553-564, pls. 18 した.ま た 脊 柱 の 彎 曲状 況 と脊 椎 骨 数 と の 関 係 も 調 べ 22. - た. Lindsey, C. C. 1962. Observations on meristic varia- 脊 柱 の 彎 曲 状 況 は キ ン ブナ 型(フ ナ5型)で は基 準 線 に tion in ninespine sticklebacks, Pungitius pungitius, 対 して 腹椎 骨 部 は上 方 に,尾 椎 骨 部 は 下方 に 位置 し,全 reared at different temperatures. Canadian J. Zool ., 40: 1237-1247, figs. 1-3. 般 に 脊 柱彎 曲度(基 準 線 と曲 線 で 囲 まれ る 部 分 の 面 積)が Lindsey, C. C. and M. Y. Ali. 1965. The effect of 小 さい.キ ンギ ョで は,ワ キ ン型(5品 種)と リ ュ ウキ ン alternating temperature on vertebral count in the 型(10品 種)に 大 別 さ れ,前 者 は キ ンブ ナ型 に近 い が, medaka (Oryzias latipes). Canadian J. Zool ., 43: 脊 柱彎 曲 度 が幾 分 大 き い.リ ュ ウキ ン型 は脊 椎 骨 がす べ 99-104, fig. 1. て 基準 線 よ り上 方 に 位 置 し,脊 柱 彎 曲 度 も さ ら に 大 き Matsui, Y. 1934. Genetical studies on goldfish of Japan. I. On the varieties of goldfish and varia- い.ラ ンチ ュ ウで は そ の 傾 向 が 特 に著 しい. tion in their external characteristics. J. Imp. Fish. 平均 脊 椎 骨 数 は フ ナ で は全 般 的 に 多 く,キ ンギ ョで は Inst., 30 (1): 1-26, pls. 1-16. In Japanese. 一般 に脊 柱 彎 曲度 が大 き くな る に従 っ て,次 第 に減 少 す Matsui, Y. 1935. Studies of Goldfish. Kodokaku, る 傾 向 が み られ る. Tokyo, 421+27 pp., 96 figs., 12 color pls. In Japa- nese. (東大 阪 市 小 若 江321近 畿 大 学 農 学 部 水 産 学 科)

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