Bult. Eur. Ass. Fish pathol. Z(t), 15, 1987 Dactylogyrusextensrs MUELLER AND VAN CLEAVE, 1932AND Dactylogyrusvostotor NYBELIN, 1924ON GILLS OF COMMON CARP Cyprinuscorpio L. By D.W. Poor_aNo J.C. CHuss From 1982 to 1985 we studied the using Naled was successfulin eliminatine biology of the Asiatic tapeworm Bothrio- infections. cephalus yamaguti, acheilognathi 1934 Examination of Dactylogyras from the (Pool, 1985). This necessitated the first batchesof carp, after mounting in purchase of batches of cultured carp one part saturated ammonium picrate Cyprinus carpio from an English supplier solution + one part glycerol (Malmberg, for experimental infection with B. 1956),revealed two species:D. extensus acheilognathi. Here we report on the Mueller and Van Cleave, 1932 and D. occurrence of Dactylogyrus extensus vastator Nybelin, 1924. D. vqstator has and D. vastator on two groups of these been recordedin Ireland by Kane (1966) fishes. from carp in a small pond near Clonmel, The first batch of 200 carp was County Tipperary, but not, as far as we obtained in March 1983. These fishes are aware, from Bri{ain. D. extensushas werel5 to 45mmin length.The gillsof all not previously been reported from of the carp were infected with up to 65 anywherein the British Isles. Dactylogyrus per fish. The parasites Dactylogyrus extensu-s(Figs. I and 2) caused considerabledamage to the gill was describedby Mueller and Van Cleave membranesand mortality of the heavily (1932) from carp collected ar Lake infected fishes. Treatment in a bath of Oneida, New York, U.S.A. D. extensus 0.5mI of 4090 formaldehydeper litre of resembles D. vastator in the lack of a water for 40 minutes (Reichenbach- ventral bar connectingthe large median Klinke, 1973)was unsuccessful. hooks of the attachment disc. but the A secondbatch of carp was collectedin copulatoryorgans and the largehooks are June1983. In thisinstance the fisheswere dissimilar in these two species.Optimal l5 to 25mm long. Dactylogyrus were water temperature conditions for D. present on the gills of 16 of 20 fishes extensusin the USSR a.d l3-15"c, but examined(8090) with I to l0 parasitesper Paperna(1964a) discovered that in Israel fish. No mortalities occurred at these this species thrived'at Z4-Z8oC, the intensitiesof infection. Treatment with normal summerwater temperaturein that Naled (Kyldane)was completelysuccess- country. ful in eliminating the Dactylogyrus Dactylogyrus vostotor (Figs. 3 and 4) infections. was described by Nybelin (1924) from Subsequentbatches of carp purchased carp in Sweden.This specieshas also been had very low levels of infections by studiedextensively because it is a serious Doctylogyrus. Preventative treatment threat to cultured carp (Paperna, 1963a, Bull. Eur. Ass. Fish Pathol. Z(l), 16, 1987 b). Optimal water conditions for ,l). References vastatorare 22-24"C (Paperna, 1963a). Gusev, A.l/. (1985). Keys to parasitesof freslr- water fish of the USSR. Volume 2 parasitic It is significantto note the competitive Metazoa (Part One). General editor Bauer, exclusion of D. extenszs by D. vostqtor O.N., Volume editor Gusev, A.V. Leningrad, reported by Paperna (1964b). This USSR; "Nauka" 425 pages.(In Russian.) Kane, M.B. (1966). Parasitesof lrish fishes. Sc.l. phenomenon was not examined in the Procs., Roy. Dub. Soc. Bl (18), 205-220. presentstudy. Malmberg, C. (1956). Om f6rekomsten av Q]ys6lsL-- It seems likely that both D. extensus t),lus pa svenskafiskar. Skr. sdd. Sver. FiskFOr, Arsskrift i,956l9-76. (Published 1957). and D. vastator are widespread on carp in Mueller, J.F. and Van Cleave, H."/. (1932). Para- the British Isles.It is unfortunate that the sitesof OneidaLake fishes.part Il. Descrinrions smaller monogeneans,especially of the of new speciesand some general raxonomic considerations, especially concerning the tre- genera Dactylogyrus and Gyrodactylus, matoda family Heterophyidae. Rooseveli Wild are rarely identified to specific level by Life annals 3(2'),79-137. (1924\. fishery biologists.Undoubtedly the large Nybelin, O. Dactylogyrus vastator n.sp. Ark. Zool., Stockholm l6(3), l-2, number of speciesof thesemonogeneans, Paperna, 1. (1963a). Some observatiolts on the together with the fact that the most biology and ecology of Dact;tlogyrus vastator in lsrael. modernkey (Gusev,1985) is not available Bamidgeh,,Isrzell5(l), 8-28. Paperna, /. (1963b). Dynamics of Dact;,lsgyy115 in English, detersfull identification. We vastator Nybelin (Monogenea) popr.rlations on would urge biologists finding these the gills of carp fry in fish potlds. Bornidgeh, parasitesto submit them to for /sruell5(l),3l-50. experts Paperna, ^L (1964a). Adaptation of Dacrylogyrus determination if they do not wish to extensus (Mueller and Van Cleave, 1932) to tackle this task themselves. Only by ecologicalconditions of artificial pondsin lsrael. Parasit. (l), having comprehensive data J. 50 90*93. about the Poperna, 1. (1964b). Competitive exclusion ol' speciesoccurring in the British Isles can Dactylogyrus extensus by Dac'lylogyrus vastu!or we be aware of the dangers from (Trematoda, Monogenea) on the gills of reared potentiallypathogenic carp. J. Parasit. 50 (l), 94-98. species. Pool, D. ttl. (1985). An experimental study of thc. biology of Bothriocephalusacheilognathi Y ama- Summary guti, 1934 (Cestoda: Pseudophyllidea).Ph.D. The occurrence of Dactylogyrtts exlenstts and, thesis,University of Liverpool. Dactylogyrus vaslator on cultured common carD in Reichenbach-Klinke, H. (1973). Fish pathology. England is described. TFH Publications,Neptune City. 512 pages. Authors'address: Departmenrof Zoology, Universityof Liverpool,P.O. Box 147,Liverpool L69 3BX, England. Bull. Eur. Ass. FishPathol. Z(l), 17, 1987 ry Dac ty logy nts e.\ | ensus. opisthaptorto show hamuli(anchorsor median hooks) and connectingbar Itig. 2: D trt' I_v I o 1g.1,n ts ex l e n s u s. copulalorvorgan. ryr l:ig. 3: Dut'tylogyt.Lt.\vastator: opisthaptor to show hamuli and connectingbar. I'ig. 4: Dut'tyfttg))rusvostutor: copulatory organ. lllack bar on l'iguresecluals 50 um. eedgih*miid*8sii*tcumi{u$!,i{J.