Korean Journal of Ichthyology, Vol. 28, No. 2, 93-99, June 216 ISSN: 122-898 (Print), 2288-3371 (Online) Received: March, 216 Revised: May 23, 216 Accepted: June 23, 216 낙동강유곡천에서식하는수수미꾸리 Kichulchoia multifasciata (Pisces: Cobitidae) 의산란시기와산란특성 김형수 * 양현 1 전북대학교자연과학대학생물학과, 부설생물다양성연구소, 1 생물다양성연구소 Spawning Period and Spawning Characteristics of Kichulchoia multifasciata (Pisces: Cobitidae) in the Yugokcheon (stream) of Nakdonggang (river) from Korea by Hyeong Su Kim* and Hyun Yang 1 (Department of Biological Science and Institute for Biodiversity, College of Natural Sciences, Chonbuk National University, Jeonju 4896, Korea; 1 Institute of Biodiversity Research, Jeonju 494, Korea) ABSTRACT Spawning period and spawning characteristics of Kichulchoia multifasciata (Pisces: Cobitidae) inhabiting the Yugokcheon (stream) of Nakdonggang (river) were investigated in the area of Segangyo (bridge), Yugok-myeon, Uiryeng-gun, Gyeongsannam-do, Korea from November 28 to October 29. The total length of population indicated that 4~ mm group is one year old, ~7 mm group is two years old and longer than 7 mm is regarded over three years old in males and 4~ mm group is one year old, ~7 mm group is two years old, 7~9 mm group is three years old and longer than 9 mm is considered over four years old in females (January 29). It has predicted that the spawning period is from May to June (water temperature in the range 21.~26.6 C). Sexually matured individuals appeared over the two years old. The number of eggs in the ovaries was 22~747 (491±4.). Key words: Kichulchoia multifasciata, spawning period, Yugokcheon, gonadosomatic index (GSI) 서 잉어목 (Cypriniformes) 미꾸리과 (Cobitidae) 어류는유럽과 아시아의담수지역에널리분포하는저서성어류로서전세계에 26속 177종 (Nelson, 26) 이보고되어있고우리나라에는 속 16종이분포하는것으로알려져있다 (Kim, 29). 이중수수미꾸리 Kichulchoia multifasciata는전장 1 cm 내외의소형어로낙동강상류의물이맑고유속이빠르며큰자갈이많은곳의바닥에서부착조류를먹고사는한국고유종이다 (Kim, 1997). 수수미꾸리는 Wakiya and Mori (1929) 가낙동강의대구부근에서채집한표본을근거로 Cobitis속의별종으로보고하였다. 이후 Sawada and Kim (1977) 은입모양, 가슴지느러미형 론 * Corresponding author: Hyeong Su Kim Tel: 82-63-27-3447, Fax: 82-63-27-3362, E-mail: kimk2k@jbnu.ac.kr 태, 등지느러미위치및척추골수의특징을기준으로 Cobitis 속으로전속하였으나 Kim (29) 은한국산미꾸리과어류의속명을재검토하면서뒷지느러미불분지기조수 4개, 등지느러미불분지기조수 6개, 수컷의가슴지느러미에골질반 (lamina circularis) 이없는점을근거로 Kichulchoia속으로정리하였다. 본종에대한연구는형태및생태 (Uchida, 1939; Chong, 1986), 핵형 (Nam et al., 1991), 초기발생 (Kim and Lee, 199), 난막구조및생식주기 (Kim et al., 211; Kim and Park, 213) 가수행된바있었으나구체적인산란생태에관한연구및논의는부족한실정이다. 일반적인미꾸리과어류의산란시기는 4~7월이며일부종의수컷은가슴지느러미골질반으로암컷의복부를압박하여암컷이산란하도록유도하는산란행동을보이는것으로알려져있다 (Bohlen, 23; Lee, 29). 수수미꾸리수컷은골질반이없고산란시기는겨울인 11~1월사이로알려져있었으나 (Kim and Lee, 199; Kim, 1997), Chong (1986) 과 Kim and 93 http://www.fishkorea.or.kr
94 김형수 양현 Park (213) 은생식소성숙도와조직학적분석을근거로본종의산란시기를 4~월로제안한바있다. 본연구는일반적인어류의산란기추정에이용되는생식소성숙도지수를 Kim and Park (213) 의연구보다더많은개체를대상으로매월분석하여정확한산란기를추정하고수컷의생식소성숙도지수가국내다른미꾸리과어류의수컷보다높고골질반이없는특징을바탕으로본종의산란습성을예측하고자하였다. 재료및방법 수수미꾸리의연구는 28년 11월부터 29년 1월까지경상남도의령군유곡면세간교일대유곡천에서족대 ( 망목, 3 3 mm) 를사용하여매월 2~2일사이에조사하였고수온과기온은오후 1~2시사이에디지털온도계를이용하여측정하였다. 채집한어류의전장은 dial caliper로.1 mm까지계측하였고체중과생식소무게는.1 g까지측정하였다. 조사지점의수심과하상구조는줄자를이용하여조사하였고하상구조는 Cummins (1962) 의기준에따라분석하였다. 연령을추정하기위해서매월채집된모든개체를대상으로전장빈도분포법 (Ricker, 1971) 에따라연령구분이가능했던 29년 1월을기준으로분석하였다. 산란시기조사를위해서만 2년생이상으로추정되는전장 9 mm 이상의개체를대상으로매달생식소성숙도지수 (gonadosomatic index, GSI= gonad weight/body weight 1) 를구하였다. 산란시기에채 집된 GSI 값이 13% 이상인암컷 1개체를대상으로해부현미경 (HA8, HITEX, Japan) 하에서포란수를계수하였다. 수수미꾸리는성적이형이나타나지않기때문에암수구분은복부를절개하여생식소를직접확인한후구분하였다. 1. 서식지환경 결과및고찰 본연구를실시한세간교일대는낙동강으로유입되는소하천으로주변은주로농경지로이용되고있었다. 하천의하폭은 ~2 m, 유폭은 ~7 m, 수심은.2~1. m였고인공보로인하여보상방은소, 하방은잔잔한여울부가이어졌다. 하상은돌 (B, C) 과자갈 (P, G) 의비율이높아 (B : C : P : G : S : SC = 1 : 2 : 3 : 3 : 1 : ) 수수미꾸리가서식하기에매우양호한환경을보였다 (Fig. 1; Table 1). 기온과수온은 29년 1월부터상승하기시작하여 7월에는각각 33.1, 31. 로가장높았 Table 1. The environmental characters at the habit of Kichulchoia multifasciata in the Yugokcheon (stream), Korea Study site Stream width (m) Water width (m) Water depth (m) Bottom structure (%)* B C P G S SC ~2 ~7.2~1. 1 2 3 3 1 *Cummins (1962): B (bolder, >26 mm), C (cobble, 26~64 mm), P (pebble, 64~16 mm), G (gravel, 16~2 mm), S (sand, 2~.6 mm), SC (silt and clay, <.6 mm) 3 3 3 27 128 18 128 21 128 24 Fig. 1. A map showing the study site of Kichulchoia multifasciata in the area of Segangyo (bridge), Yugok-myeon, Uiryeng-gun, Gyeongsannam-do, Korea.
수수미꾸리의산란시기와산란특성 9 으며 1월에는 3., 4.1 로가장낮게나타났다 (Fig. 2). 본종은미꾸리과어류중수심이얕고빠른여울부의돌및자갈바닥에서주로서식하고있어여울부의돌및자갈하상에서주로활동하는참종개 Iksookimia koreensis (Kim, 1978), 새코미꾸리 Koreocobitis rotundicaudata (Byeon, 27) 와유사하였다. 수수미꾸리의서식환경은일본산 Niwaella delicata와비슷하였는데 (Hiramatsu, 24) 최근까지두종은형태적특징이유사하여 Niwaella속에포함되어있었던유연관계가매우가까운종들로 (Sawada and Kim, 1977) 산란시기가겨울또는봄이며수컷생식소가특이적으로발달하는특징이나타나고있어형태와생태적특성이유사하게진화한것으로추정된다 (Kim and Lee, 199; Nakabo, 22). 2. 연령추정본종의연령을추정하기위해서암수를구분하여전장을측 정하였고전장빈도분포법에의해분석한결과는 Fig. 3와같다. 가장다양한크기가채집되었고연령구분이가능한 29년 1 월조사를기준으로연령을비교한결과암컷과수컷의전장은유사하게나타났다. 수컷은전장 4~ mm 군은 1년생, ~ 7 mm 군은 2년생, 7 mm 이상군은 3년생이상으로추정되었고암컷은전장 4~ mm 군은 1년생, ~7 mm 군은 2년생, 7~9 mm 군은 3년생, 9 mm 이상군은 4년생이상으로추정되었다. 채집된개체중가장큰개체는수컷 121.9 mm (7.92 g), 암컷 131.4 mm (9.2 g) 이었다. Chong (1986) 은 7월기준으로본종의연령을추정한결과 ~7 mm 군은당년생, 8~1 mm 군은만 1년생, 1~13 mm 군은만 2년생, 13 mm 이상은만 3년생군으로추정한바있는데본조사의결과와는차이가있었다. 이는조사지점, 조사시기, 환경적요인및분석결과의해석차이로인한것으로사료되며이석과비늘을이용한정확한연령분석이추가되어야할것으로생각된다. Kano (2) 는일본산 N. delicata의이석과비늘을분석하여연령을추정한결과수컷이 2.년생까지는더성장이빠르나이후암컷이더크게성장한다고언급하였는데본종의전장분포도에서도 7 mm 이하의개체에서는작은암컷개체가다수확인되고조사기간별 Fig. 2. Monthly changes in the air and water temperature in the Yugokcheon (stream) of Nakdonggang (river), Korea from November 28 to October 29. Fig. 3. Total length frequency distribution of Kichulchoia multifasciata in the Yugokcheon (stream), Korea on January 29. 2 A Female 2 B Male Gonadosomatic index (GSI) 1 1 Nov. Dec. Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec. Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. 28 29 28 29 Month Fig. 4. Monthly change of gonadosomatic index (GSI) of Kichulchoia multifasciata (A: female, B: male) in the Yugokcheon (stream), Korea from November 28 to October 29. Vertical lines show SD.
96 김형수 양현 2 January (n=7) Female 2 January (n=64) Male 1 1 3 2 February (n=77) 2 February (n=) 1 1 2 March (n=6) 2 March (n=6) 1 1 Gonadosomatic index (GSI) 2 2 1 April (n=9) 2 1 April (n=114) 2 May (n=44) 2 May (n=2) 1 1 2 June (n=49) 2 June (n=4) 1 1 2 4 6 8 1 12 14 2 4 6 8 1 12 14 Total length (mm) Total length (mm) Fig.. Relationship between gonadosomatic index (GSI) and total length of Kichulchoia multifasciata ( : female, : male) in the Yugokcheon (stream), Korea from January to June 29.
수수미꾸리의산란시기와산란특성 97 Table 2. Comparisons of ecological characters in Cobitidae fishes by each investigator Species Spawning period Water temperature ( ) Egg number *GSI in spawning period (female/male) Authors Cobitis tetralineata June to July 22~26 1,288±83 (474~2,976) 14.1/2.3 Kim et al. (26) C. lutheri July 24~26 1,127±43 (47~2,8) 2.6/2.6 Ko and Park (211) Iksookimia hugowolfeldi June to July 21~22 933±4 (731~1,249) 14.7/2.2 Park (216) I. koreensis June 2~26 1,138±431 (9~2,23) 23.3/. Kim (1978) I. longicorpa June 2~24 2,42±944 (1,4~,4) 17.8/6.3 Kim and Ko (2) I. pacifica June to August 2~27 89±29 (27~1,26) 6./.6 Choi and Byeon (29) I. pumila May 2 328±23 (142~878) 2.3/2. Kim and Lee (1984) Kichulchoia multifasciata March to May 14~21 491±4 (22~747) 16.8/9.2 Present study Koreocobitis naktongensis May to June 17~2 22,643±4,629 (,99~3,323) 13.2/- Hong et al. (211) K. rotundicaudata May to June 2~23 1,36±72 (439~2,9) 8.8/.7 Byeon (27) *GSI: gonadosomatic index 로수컷보다전장이큰암컷개체가지속적으로출현하고있어두종은유사한성장패턴을보이는것으로판단된다. 3. 산란시기수수미꾸리의산란시기를추정하기위하여 GSI를분석한결과암컷은 6월에.13~7.9% (2.±1.4) 로가장낮았고 2 월에 4.4~24.89% (13.7±4.97) 로가장높았다. 수컷은 7월에 2.2~2.9% (2.43±.32) 로가장낮았으며 1월에 6.22~ 14.1% (11.14±2.34) 로가장높게나타나암컷과유사하였다. 특히, 암컷과수컷은모두 12월부터이듬해 월까지평균 8.% 이상의높은 GSI를보였고암컷은 1월부터 월까지 1.% 이상의값을나타냈다 (Fig. 4). 3월에는 GSI가일부감소하는경향을보였으나전반적으로높게유지되었고 6월이후급격히감소하는것으로미루어본종의산란시기는 ~6 월로추정된다 (Fig. ). Kim and Lee (199) 는본종의초기생활사연구에서 12월과 1월에채집된개체를사용하여인공수정하였고발생과정을보고하면서산란기를 11월부터 1월로추정한바있다. 본연구결과와비교하여추론해보면이전연구 (Kim and Lee, 199) 가가능했던이유는본종이 12월겨울부터이듬해봄 월까지성숙한난모세포와정모세포를가지고있었기때문에산란성기가아니었지만호르몬처리로인한인공수정이가능했던것으로추정된다. 겨울부터이듬해봄까지높은 GSI 가유지되는점, 조직학적분석을통해 4~월에성숙한난모세포가대부분나타나는점, 6월이후급격히감소하는점을종합적으로고려하면수수미꾸리의산란시기는 ~6월로추정되며이때의수온은 21.~26.6 범위였다. 이는본종의산란기를 4~월로추정한 Chong (1986) 과 Kim and Park (213) 의결과보다 1달정도느린것으로나타났고환경적요인에의한차이라고생각된다. 산란시기가 월로알려진부안종개 I. pumila (Kim and Lee, 1984), ~7월로알려진줄종 Table 3. The sex ratio of Kichulchoia multifasciata in the Yugokcheon (stream), Korea from January to October 29 Month Female Male Total Sex ratio χ 2 Jan. 7 64 134.91.27 Feb. 77 127.6.74 Mar. 6 6 112 1.. Apr. 9 114 173 1.93 17.49 May 44 2 96 1.18.67 Jun. 49 4 94.92.17 Jul. 47 12.8.63 Aug. 2 4 97.87.1 Sep. 7 43 1.7 1.96 Oct. 64 3 99. 8.49 Total 83 1 1,134.9.9 The critical value for χ 2 goodness-of-fit test of equal numbers of females and males (1 df) at 9% significance is 3.84 개 C. tetralineata (Kim et al., 26), 점줄종개 C. lutheri (Ko and Park, 211), 남방종개 I. hugowolfeldi (Park, 216), 참종개 (Kim, 1978), 왕종개 I. longicorpa (Kim and Ko, 2), 북방종개 I. pacifica (Choi and Byeon, 29), 얼룩새코미꾸리 K. naktongensis (Hong et al., 211) 등국내미꾸리과어류와유사한것으로판단된다 (Table 2). 4. 성비, 성숙연령, 포란수 수수미꾸리는조사기간중암컷이 83개체, 수컷이 1개체가채집되어성비는 1 :.9로나타나암수간의성비는유의한차이가없는것으로조사되었다 (χ 2 =.9, P>.; Table 3). 그러나 Chong (1986) 은본종의성비 ( 암컷 : 수컷 ) 는 1 :.73 로암컷이수컷에비해많다고보고하여결과차이가나타났다. 다른국내미꾸리과어류의성비는줄종개 1 :.7 (Kim et al., 26), 점줄종개 1 :.78 (Ko and Park, 211), 참종개 1 :.7 (Kim, 1978), 왕종개 1 :.6 (Kim and Ko, 2) 로암컷이다소많은상태의성비를보여주고있었고추후여러지역의성
98 김형수 양현 Table 4. The relationship among the total length, body weight, gonadosomatic index (GSI) and egg number in the ovaries of Kichulchoia multifasciata in the Yugokcheon (stream), Korea from April to May 29 No. of individuals Total length (mm) Body weight (g) Gonadosomatic index (GSI) Egg number 1 89.32 2.76 13.77 22 2 97.4 4.23.13 336 3 1.28. 17.8 4 4 13.82.81 17.9 468 17.71.79 16.6 481 6 112.6 6.3 18.89 4 7 117.14 8.68 2.62 747 8 12.8 7. 14.3 463 9 122.79 8.61 17.6 668 1 126.63 8.2.84 41 Mean±SD 19.86±12.19 6.27±1.9 16.82±2.12 491.49±4.2 비를조사하여야정확하게나타날것으로생각된다. 수수미꾸리의생식소가발달하기시작하고성적으로성숙하여산란에참여하는개체군의전장범위와연령을조사하였다. GSI는암컷과수컷모두전장 8 mm 내외에서 1월부터 월까지높게유지되었고 6월부터는급격하게감소하는바만 2년생부터성숙하는것으로판단되며일부만 1년생개체도조기성숙하는것으로판단된다 (Fig. ). 이는줄종개 (Kim et al., 26), 참종개 (Kim, 1978), 왕종개 (Kim and Ko, 2), 북방종개 (Choi and Byeon, 29) 와유사하게나타났다. 다만일부전장 8 mm 이하의일부개체에서도 GSI가높게나타났는데만 2년생이하의개체가조기성숙에의한스니커행동으로산란에참여하는지에관해서는면밀한조사가요구된다. 4~월에 GSI가 13.% 이상인전장 8 mm 이상의성숙한암컷 1개체의난소를적출하여포란수를계수한결과 22~ 747개 (491±4.) 였고전장이커질수록포란수가증가하는경향이나타났다 (Table 4). 이는부안종개 328개 (142~878), 동일속의좀수수치 K. brevifasciata 69개 (18~16) 보다는많았으나 (Ko and Bang, 214) 다른미꾸리과어류보다는적었다 (Table 2).. 산란유형추정일부어류에서는다수의수컷과다수의암컷이산란에참여하는다부다처제 (polygynandry) 의산란습성을이용하는것으로알려져있다 (Moyle and Cech, 24). 미꾸리과의미꾸리 Misgurnus anguillicaudatus (Kim, 1997), C. taenia (Bohlen, 1999), 미호종개 C. choii (Lee, 29) 는수컷이가슴지느러미골질반을암컷의복부에고정하고압박하여산란하는일부일처제 (Monogamy) 의산란습성을이용하는것으로알려져있다. 담수에서은어 Plecoglossus altivelis (Ko et al., 27), 쏘가리 Siniperca scherzeri (Lee et al., 212) 와같은어류의수컷은 GSI가각각 8.% 내외, ~12% 로높은편이며이들종은다부다처제의집단산란에참여하는것으로알려져있다 (Kim, 1997). 현재까지미꾸리과어류가운데다부다처제의산란에대한보고는없었다. 본연구에서는수수미꾸리의산란을직접확인하지못하였고본종이다른미꾸리과어류보다체고에대한체장의비가높아골질반이없어도몸을감아서산란할가능성도있지만수컷가슴지느러미골질반이없고수컷의 GSI 가 8~1% 로높으며산란시기에자연상태에서수컷의정액이매우쉽고진하게나오는점으로판단하면본종은다부다처제의집단산란습성을이용할가능성도있을것으로추정된다. 요 본연구는 28년 11월부터 29년 1월까지경상남도의령군유곡면세간교일대유곡천에서수수미꾸리의산란시기와산란특성에대해조사하였다. 수수미꾸리의연령을분석한결과수컷은 1년생전장 4~ mm, 2년생 ~7 mm, 3년생 7 mm 이상, 암컷은 1년생 4~ mm, 2년생 ~7 mm, 3년생 7~9 mm, 4년생 9 mm 이상으로추정되었다 (29년 1 월기준 ). 산란시기는 ~6월사이로추정되었고 ( 수온 21.~ 26.6 ) 성적으로성숙하는연령은만 2년생이상으로판단되었으며포란수는 22~747개 (491±4.) 로나타났다. 사 본연구기간동안현장조사와시료분석에도움을준홍양기박사님, 장준호, 고재근, 이강식연구원에게감사드립니다. 약 사 REFERENCES Bohlen, J. 1999. Reproduction of spined loach, Cobitis taenia, (Cypriniformes; Cobitidae) under laboratory conditions. J.
수수미꾸리의산란시기와산란특성 99 Appl. Ichthyol., : 49-3. Bohlen, J. 23. Spawning habitat in the spined loach, Cobitis taenia (Cypriniformes, Cobitidae). Ichthyol. Res., : 98-11. Byeon, H.K. 27. Ecology of Koreocobitis rotundicaudata (Cobitidae) in the Naerin stream, Korea. Korean J. Ichthyol., 19: 299-3. (in Korean) Choi, J.K and H.K. Byeon. 29. Ecological characteristics of Cobitis pacifica (Cobitidae) in the Yeongok stream. Korean J. Limnol., 42: 26-31. (in Korean) Chong, D.S. 1986. Morphological and bionomical studies of Niwaella multifasciata (Wakiya et Mori). Master thesis, Chonbuk Nat. Univ., 37pp. (in Korean) Cummins, K.W. 1962. An evaluation of some techniques for the collection and analysis of benthic samples with special on lotic waters. Amer. Midl. Nat., 67: 477-4. Hiramatsu, K. 24. Habitat analysis of Ajime-loach (Niwaella delicata) in the Ai river. Bull. Agric. Food. Environ. Res. Ctr. Osaka., 4: 34-4. (in Japanese) Hong, Y.K., H. Yang and I.C. Bang. 211. Habitat, reproduction and feeding habit of endangered fish Koreocobitis naktongensis (Cobitidae) in the Jaho stream, Korea. Korean J. Ichthyol., 23: 234-241. (in Korean) Kano, Y. 2. Age and growth of the Ajime-loach, Niwaella delicata, in the Yura river, Kyoto, Japan. Ichthyol. Res., 47: 183-186. Ko, M.H., I.S. Kim, J.Y. Park and Y.J. Lee. 27. Distribution and ecology of a land-locked ayu, Plecoglossus altivelis (Pisces: Osmeridae) in lake Okjeong, Korea. Korean J. Ichthyol., 19: 24-34. (in Korean) Ko, M.H. and J.Y. Park. 211. Growth and spawning ecology of Cobitis lutheri (Teleostei: Cobitidae) in the Mangyeong river, Korea. Korean J. Ichthyol., 23: 8-162. (in Korean) Ko, M.H. and I.C. Bang. 214. Spawning character and early life history of the endangered Korean dwarf loach, Kichulchoia brevifasciata (Teleostei: Cobitidae). Korean J. Ichthyol., 26: 89-98. (in Korean) Kim, C.H., J.G. Kim and J.Y. Park. 211. Structure of egg envelope and oogenesis of Kichulchoia multifasciata (Pisces, Cobitidae). Korean J. Microscopy, 41: 189-196. (in Korean) Kim, I.S. 1978. Ecological studies of cobitid fish, Cobitis koreensis in Jeonju-cheon creek, Jeonrabug-do province, Korea. J. Eoc. Environ., 2: 9-14. (in Korean) Kim, I.S. 1997. Illustrated encyclopedia of fauna and flora of Korea. Vol. 37. Freshwater Fishes. Ministry of Education, 629pp. (in Korean) Kim, I.S. 29. A review of the spined loaches, family Cobitidae (Cypriniformes) in Korea. Korean J. Ichthyol., 21: 7-28. Kim, I.S. and M.H. Ko. 2. Ecology of Iksookimia longicorpa (Cobitidae) in the Seomjin river, Korea. Korean J. Ichthyol., 17: 112-122. (in Korean) Kim, I.S., M.H. Ko and J.Y. Park. 26. Population ecology of Korean sand loach Cobitis tetralineata (Pisces; Cobitidae) in the Seomjin river, Korea. J. Ecol. Field Biol., 29: 277-286. (in Korean) Kim, I.S. and E.H. Lee. 199. Studies on early embryonic development of Niwaella multifasciata (Pisces: Cobitidae). Korean J. Limnol., 28: 4-462. (in Korean) Kim, I.S. and W.O. Lee. 1984. Morphological and ecological aspects on the population of Cobitis koreensis Kim (Pisces, Cobitidae) in the Begchon stream, Puan-gun, Cholla-bugdo, Korea. Korean J. Ecol., 7: 1-2. (in Korean) Kim, J.G. and J.Y. Park. 213. Reproductive cycle of the Korean loach, Kichulchoia multifasciata (Pisces: Cobitidae). Korean J. Ichthyol., 2: 216-221. (in Korean) Lee, I.R. 29. Studies on the conservation biology of an endangered freshwater fish, Iksookimia choii. Doctoral dissertation, Soonchunhyang Univ., 167pp. (in Korean) Lee, W.O., J.M. Back, J.H. Lee, K.H. Kim, C.H. Kim and S.W. Yoon. 212. Sexual maturation and feeding habit of Korean mandarin fish, Siniperca scherzeri (Perciformes, Centropomidae) in the Seomjin river and Imjin river, Korea. Kor. J. Env. Eco., 26: 7-66. (in Korean) Moyle, P.B. and J.J. Cech. 24. Fishes: an introduction to ichthyology ( th ed.). Benjamin Cummings, USA, 744pp. Nakabo, T. 22. Fishes of Japan. Tokai Univ. Press, Tokyo, 18pp. Nam, M.M., H.J. Yang and B.S. Chae. 1991. The karyotypic analysis of Niwaella multifasciata Wakiya et Mori (Cobitidae), an endemic species in Korea. Korea J. Ichthyol., 3: 36-41. (in Korean) Nelson, J.S. 26. Fishes of the world (4 th ed). John Wiley and Sons, Inc., Canada, 61pp. Park, C.W. 216. Ecology of the endemic Korean southern king spine loach, Iksookimia hugowolfeldi. Master thesis, Chonbuk Nat. Univ., 6pp. (in Korean) Ricker, W. E. 1971. Methods for assessment of fish production in freshwater. IBP hand book, 3: 112-113. Swada, Y. and I.S. Kim. 1977. Transfer of Cobitis multifasciata to the genus Niwaella (Cobitidae). Jpn. J. Ichthyol., 24: - 16. Uchida, K. 1939. The fishes of Tyôsen (Korea). Part 1. Nematognathi and Eventognathi. Bull. Fish Exp. Sta. Government-General Tyôsen, 6: 1-8+1-48. (in Japanese) Wakiya, Y. and T. Mori. 1929. On two new loaches of the genus Cobitis from Korea, Chosen Nat. Hist. Soc., 9: 31-33.