VERTEBRATA HUN GA RICA M USE I HISTOR ICO-NATUR ALIS HUN GARICI Fase. 1-2.

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VERTEBRATA HUN GA RICA M USE I HISTOR ICO-NATUR ALIS HUN GARICI Fase. 1-2. Ichthyological Notes II. On the Biology of Breeding of Carassius auratus gibelio (Bloch) By L.

1 VERTEBRATA HUN GA RICA M USE I HISTOR ICO-NATUR ALIS HUN GARICI Fase Ichthyological Notes II. On the Biology of Breeding of Carassius auratus gibelio (Bloch) By L. Berinltey Zoological Department of the Hungarian Natural History Museum, Budapest It is a well-known fact that the testicula of Caraasiua auratus gibelio /BLOCH/ transform into ovarla in its second year of age ( to wit, the males become females. And at their subsequent spawning,the spawns are fertilised,by ggpegenese, by other species of the family Cyprlnidae. As it happens,the sperm will penetrate the spawn, and the dividing process of the egg will take place, but the sperm does not unite Itself with the ovulum and thus, in essentials, the offspring comes into being by parthenogenesis. According therefore to our present knowledge, the reproduction of this species happens, after the transformation of the males, in the way described above. The usual course of breeding is truly this, but, in my opinion, it will not infrequently happen that the sperm penetrating the spawn will unite with the ovulum, causing a regular fertilization. This seems the more probable as the frequent hybridization among the species of the family Cyprlnidae ÍB widely known. The correctness of my assumption is substantiated by the following facts.

During the gathering of the fishes of the fish-pond /fed by the waters of the Sárviz channel/ in the state farm of Nagyhörcsökpuszta on 23 October 1958, I captured two hybrid specimens of Carassius

2 During the gathering of the fishes of the fish-pond /fed by the waters of the Sárviz channel/ in the state farm of Nagyhörcsökpuszta on 23 October 1958, I captured two hybrid specimens of Carassius caraeslus L. and Caraeelus auratus gibelio /BLOCH/. No hybrid of the two species were as yet known. That the parent-species of the hybrids examined by me did really belong to the two species mentioned above and that the regular fertilization of the egg /the unison of the sperm and the ovulum/ did actually occur are verified by the fact that the characteristics! features of both parent species were manifest on the hybrids* The parent species differ from each other in several morphological and osteological characters, the most conspicuous ones being the following: the body of the typical form of Carassius carasslua is very high, about half the length of the body. The back is highly arched. The mouth is terminal, but the oral cleft, in a lateral view, turns obliquely upward. The dorsal fin is long and high, its posterior margin strongly convex ; the last undivided ray of the dorsal and anal fins constitutes a strong spine, densely and minutely teethed on its posterior side /number of teeth about 30/. There are regularly 6 divided rays in the anal fin.some scales lie along the lateral line. A vivid dark spot ornaments the caudal peduncle of juvenile specimens.becoming gradually evanescent on adult animals. The number of spines on the first branchial arch is 23-35, usually 26-31; the spines are short.the number of vertebrae vary between The body of Carassius auratus gibelio is lower, its dorsal outline more weakly arched.the mouth is also terminal but the oral cleft, when viewed laterally, is not oblique but straight. The dorsal fin is long and high,but its margin is not convex but straightly truncate. The last undivided ray of the dorsal and anal fins constitute a strong spine each, with rarely spaced, large teeth on its posterior side, the number of teeth may be The scales are large, with

3 pi« Spine of dorsal fin. Fig. 1, CaraBBius carassiub ; fig. 2. Carassius auratus gibelio ; fig. 3. Hybrid. /The figures were drawn by my collègue, L. ESZTERGÁLYOS./

28-31 oblique rows of scales along the lateral line. There is no dark spot on the caudal peduncle of Juvenile specimens. The branchial spines are long, 39-50 on the first branchial arch.

4 28-31 oblique rows of scales along the lateral line. There is no dark spot on the caudal peduncle of Juvenile specimens. The branchial spines are long, on the first branchial arch. There may be vertebrae.usually The two species differs also in several osteological characters, but I will not discuss the differences now. Examining the hybrid specimens from the point of view of finding out in which of their characters they resemble one or the other of the parent species, I was able to establish the followings: they agree with Carassius carasslus in: 1. the situation of the oral cleft, 2. the presence of the conspicuous black spot on the caudal peduncle, 3. the number of the divided raye of the anal fin, 4. the numbers of the branchial spines and 5. the vertebrae, as well as 6. in the shape of the vomer, the frontale, and the hyomandibulare. They conform to the characteristics of Carassius auratus gibello in: l.the shape of the dorsal fin, 2. the number of scales along the lateral line, 3. the length of the branchial spines, and 4. the shape of the besloccipitale the urohyale, and the articulare. ïinally, they occupy an intermediate position in: 1. the number of the teeth on the rays of the dorsal and anal fins, 2. the shape and structure of the operculum, and 3. the shape of the pharyngeal arches /ossa pharyngea inferiors/ /Pig. 1-9./. On the basis of the mutual presence of the characteristlcal features as discussed above of the parent species on the hybrids, it can be shown indubitably that a regular fertilization took place.in my opinion,regular fertilization may occur also in the case of Carassius auratus gibelio, and the hybrids of this species may be as frequent as those of the other species of the family Cyprlnidae.

5 4 S 6 Pig Operculum. Fig. 4. Carassiuo caraselus ; fig. 5. CaraaaiuB auratus gibelioj fig. 6. Hybrid. 7 e» Pig Os pharyngeus inferioris. Pig. 7. Carassiu8 carassius; fig. 8. Carassius auratus gibelio; fig. 9. Hybrid

6 Ichthyológiai jegyzetek II. Az ezüstkárász (Carasssus auratus gibelio BLOCH) szaporodás-biológiájáról Irta: Berinkey László Természettudományi Múzeum, Budapest Szerző a bevezetésben az ezüstkárász szaporodásmódját ismerteti, s közli, hogy e faj hímjeinek testiculumai 2 éves korban ovariummá alakulnak át, azaz a himek nőstényekké válnak. Ezután iváskor ikráikat gynogenezis utján már a Cyprinidae család más fajai termékenyítik meg, melynek megtörténtével a sperma behatol ugyan az ikrába,s ennek eredméayobént meg is indul a pete barázdálódása, de a sperma az ovolummal nem egyesül,s az utód lényegében parthenogenezissel Jön létre. Továbbiakban a szerző leirja, hogy gyűjtései folyamán a Carasslus caraaslus L. és a Carassius auratus gibelio /BLOCH/ 2 hybrid példányára akadt, s ezeket megvizsgálta abból a szempontból, hogy mely tulajdonságaik egyeznek meg a kárász és az ezüstkárász jellegzetes morphológiai és csonttanl bélyegeivel. Kutatásai során megállapította, hogy mivel a hybrideken a két szülőfaj jellegzetes tulajdonságai világosan felismerhetők, a szülők faji hovatartozása kétségtelen, s a pete szabályos megtermékenyítése /a sperma és az ovulum összeolvadása/ megtörtént. Végezetül kijelenti, hogy véleménye szerint az ezüstkárásznál ugyanugy előfordulhat a szabályos megtermékenyítés is, se faj hybridjei legalább olyan gyakoriak lehetnek, mint a Cyprinidae család többi fajainál.

7 R e f e r e n c e s 1. BERG, L.S. : Ryby presznih vod C.C,C.?. i szopredelnih BEtran /Moszkva-Leningrád,1949,1-3, pp.1381/ BERINKEY, L.: Purther Morphological and Osteological Investigations on the Hybrid8 of Hungarian Cyprinids /Ann. Hist. Nat. Mus. Nat. Hung. 52, 1960, p / CARAUSU, S.: Tratat de Ichtiologie /Bucuregti, 1952, pp.802/ GROTE, W. & VOGT, C. k HOPER, B.: Die SUsswasserfIsche von Mitteleuropas /Frankfurt ara M,, 1909, pp.558/ GÜNTHER, A.! Catalogue of the Pishes in the British Museum /London, 1868, 7, pp. 512/ HECKEL, J. & KNER, R.: Die SUsswasserfische der österreichischen Monarchie mit Rücksicht auf die angrfinzenden Länder /Leipzig,1858,pp.388/ SIEBOLD, E.Th.: Die Süsswasserfische von Mitteleuropa /Leipzig, 1863, pp. 430/.

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