"Monogenean parasites from fishes of the Nile in Egypt" -

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1 Parasit, hung Monogenean parasites fromfishesof the Nile in Egypt Dr. Kálmán MOLNÁR Dr. Ismail MOSSALAM Veterinary Medical Research Institute, Hungarian Academy of Sciences, Budapest, Hungary Faculty of Veterinary Medicine, University of Zagazig, Zagazig, Egypt Molnár, K. - Mos- "Monogenean parasites from fishes of the Nile in Egypt" - salam, I. - Parasit, hung., _18: ABSTRACT. Four species of Monogenea were found on the gills of Nile fishes in Egypt. Detailed redescription of Jainus nur sei (Ergens, 1973) found on Alestes dentex and Quadriacanthus clariadis Paperna, 1961 from Clarias lazera are given. Data on the incidence and short descriptions of two Gyrodactylus spp. from the latter fish species are also given. KEY WORDS. Monogenea, Fishes, Quadriacanthus, Jainus, Gyrodactylus, Egypt (Nile). Until recently little attention has been paid to Monogenea living in African fishes. The majority of the species have been described from Ghana and Uganda (PAPERNA, 1965, 1968a, 1968b, 1969, 1973 and PAPERNA and THURSTON, 1968, 1969a, 1969b). Studies on fish monogeneans in Egypt have been carried out by FISCHTHAL and KUNTZ (1963) and ERGENS (1973a, 1973b, 1981). The present paper reports the occurrence of four monogenean species in Nile fishes in Egypt. MATERIALS AND METHODS Examinations were made in February and March, 1984 on fishes collected by seine from Bahr Mouis, a branch of the Nile near Zagazig. Forty-two specimens of five fish species were examined (Çlaji_as_lazera 10; AT^es^esjdentex 1; Tilagia_nilotica_20; T. _galilaea 8; T. zielli 3). A complete parasitological examination was performed. The fish were examined under stereomicroscope immediately after extermination. Monogeneans collected from the fish were preserved as slide preparations in ammonium picrate solution under cover slip. GUSSEV's (1983) methods were used for measuring the sclerotised elements. Drawings and measurements were made with the aid of camera lucida. Measurements are presented in micrometers unless otherwise stated, with mean followed by range in parentheses. RESULTS No monogenean infection was found in Tilapia spp. The following parasites were found in Cla Jäzera and Aleste^dentex^ Jainus nursei (Ergens, 1973) - (Fig. 1). syn. : Characidotrema nursei Ergens, 1973 Host: A^e^tes_d_entex Locality: Bahr Mouis near Zagazig.

2 Location: gill filaments Number of species studied: 5 Description: Body elongated, tapering at anterior and posterior ends. Body length 1.0 (0.6- I. 1), width 0.16 ( ) mm. Cephalic lobes present. Four pigmented eye spots on the anterior end. Haptor elongated with 14 hooks and a pair of dorsal and ventral anchors. Dorsal anchors simple with well developed inner roots and an elongated bar. Total length of dorsal anchors (between the inner root and the point) 25 (24-26). Outer length 18 ( ). Inner root 10 (8-11) long. Outer root very short, not extending 2 in length. Point (9.3- II. 2) long. Length of the bar between dorsal anchors ( ), width 2. 0 ( ). Ventral anchors with short blades and well developed roots. Their total length (between the outer root and the point) 18 ( ). The point is fixed by a small sclerotised part of the haptor. Inner length 11.6 (11-12). Roots forming right angle with each other. Inner roots sometimes with a small protrusion. Length of outer root 7.0 ( ), that of inner one 5.6 ( ). Point short, its length 3. 0 ( ). Fig. 1. Sclerotized organs of Jainus nursei da: dorsal anchor, va: ventral anchor, b: bars, co: copulatory organ, v: vagina, h: hooks Horse-shoe shaped bar with two anterio-lateral processes and a small posteriorly directed process in the centre. Length of the bar ( ), width 2. 7 ( ), length of the anterio-lateral processes 12.9 ( ). Hooks similar and of embriónál type, with a length of 17 (15-18). Copulatory organ consisting of a 44 (40-48) long cirrus which originates from an oval solid funnel. One additional plate attached to rim of funnel and another one to distal portion of cirrus. A sclerotised vagina, composed of a long tube, measures 41 (38-43) in length. On the basis of morphological characteristics and the measurements of sclerotised elements we have identified this species as J. nur sei, a monogenean described by ERGENS (1973) from the gills of Ah^^es_nursei in Egypt. The present finding is a new host record.

3 Quadriacanthus clariadis Paperna, (Fig. 2a, b, 3, 4) Host: Cl Laria_s_lazera Locality: Bahr Mouis Location: gill filaments Number of specimens studied: 10 Description: Body elongated, with four groups of head organs, two pairs of eyespots and an opisthaptor well delimited from the rest of the body by a narrow construction. Haptor with 14 hooks and two pairs of anchors of different shapes and sizes. Body length ( ) mm, width ( ) mm. Anchors simple, with sharply bending shafts, without roots but having an appendix which joins the bars. Length of dorsal anchor ( ), width of its base 15.7 ( ). Point very short, 3.4 ( ) long. Appendix 22 (17-30) in length. Dorsal bar with trapezoid base, lateral extensions and a central process. Length of the bar 25 (22-28), width at its centre 17 ( ), width with lateral extensions 36 (30-38). Length of central process 15 ( ). Ventral anchors resembling dorsal ones but small- Fig. 2. Sclerotized organs of Quadriacanthus clariadis er in size and with more developed point. Length of ventral anchors 44 (30-47), base 14 (10-16) wide, point 11.5 (10-14), appendix 9.5 (8-11) long. Ventral bar-consisting of two rods, each 43 (38-46) long and 8.8 ( ) wide, forming a V-shaped structure. Hooks different in size. A pair close to the dorsal anchors 33 (30-36) in size, another pair close to the ventral anchors 21.5 ( ), the rest 15 ( ) in length. Copulatory organ consisting of a 57 (47-60) long, slightly bending tube, and an elongated bilobed accessory piece. The vagina is an elongated tube, measuring 49 (22-52). Three species of Quadriacanthus are known from the gills of Clarias spp. Qu. clariadis was described by PAPERNA (1961) from C^ariasjazera in Israel, Qu. voltaensis by PAPERNA (1965) from Ç^aj^ajj^alkeri in Ghana, while Qu. kobiensis by HA KY (1968) from Clarias batracus in Viet-Nam. The species found by us differs from Qu. voltaensis in the shape of the sclerotised organs, from Qu. kobiensis in the shape of the copulatory organ, but resembles J3u_ 1_c2aj~ijKlis in many respects.

4 On the basis of main their morphological characteristics we classified our specimens as Qu. clariadis. Minor differences between our findings and the original description concern the shape of the ventral bar and the copulatory organ. In our preparations the shape of the ventral bar is about the same as depicted by HA KY (1968) for Qu. kobiensis. The copulatory organ has a well-developed and differentiated accessory piece, more over a solid vagina was detected in the fully mature specimens. In the less developed, juvenile forms, however, a sclerotized vagina was not observable, and the structure of the copulatory organ resembled the ones depicted by PAPERNA (1961). We suppose that the specimens studied by PAPERNA were relatively young stages, and the redescription of Qu. clariadis by us reflects the species characteristics more precisely. Gyrodactylus sp. I. - (Fig. 5) Host: Clarias_lazera Locality: Bahr Mouis Location: gill filaments Number of specimens studied: 1 Description: Body length 1.0 mm, width 0. 3 mm. Anchors 77 long. Length of basal part 52, that of the root 30. Point 27 long. Ventral bar with two lateral processes, 19 long and 6. 3 wide. Dorsal bar 18 long and 2 wide. Hooks 38 long with reflexed hooklets measuring 8 in length. This species seems to be identical with Gyrodactylus rysavyi Ergens, Gyrodactylus sp. II. - (Fig. 6) Host: Çlarias_laz_era Locality: Bahr Mouis Location: gill filaments Number of specimens studied: 2 Description: Body length mm, width mm. Anchors , their basal part , root 14-16, point long. Ventral bar long and 5 wide. Dorsal bar not observable. Hooks long with hooklets of 8 in length. This species seems to be identical with Gyrodactylus groschafti Ergens, MOLNÁR, K. MOSSALAM, I.: Monogenetikus mételyek nílusi halakból Egyiptomban A szerzők Egyiptomban nilusi halakon végzett vizsgálataik nyomán négy Monogenea-fajt mutattak ki. Ezek közül a közleményben az Alej3^e_s_déntex nevü halról gyűjtött Jainus nursei és a n e v ü halról gyűjtött Quadriacanthus clariadis esetében részletes újraleírást adnak. A Ç^ajias^azera-n talált két Gyrodactylus-fajt közelebbről nem határozták meg, bár azok méreteik és a mellékelt fotók alapján valószínűleg a G. rysavyi és G. groschafti fajokkal azonosak. Legend to the figures: Fig. 3. a and b. Microphotographs of the haptoral elements of Qu. clariadis Fig. 4. Microphotograph of the copulatory organ of Qu. clariadis Fig. 5. Microphotograph of the anchors of Gyrodactylus sp. I. Fig. 6. Microphotograph of the anchors of Gyrodactylus sp. II.

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7 REFERENCES ERGENS, R. (1973a): Two species of Gyrodactylus from Clarias lazera (Vermes, Trematoda, Monogenoidea). - Rev. Zool. Bot. Afr., 87: ERGENS, R. (1973b): Characidotrema nursei sp. nov. from the gills of Alestes nurse from River Nile. - Rev. Zool. Bot. Afr., 87: ERGENS, R. (1981): Nine species of the genus Cichlidogyrus Paperna, 1960 (Monogenea: Ancyrocephalinae) from Egyptian fishes. - Folia Paras. (Praha), 28: FISCHTHAL, J. H. - KUNTZ, R.E. (1963): Trematode parasites of fishes from Egypt. Part. 2. Diplozoon aegyptensis (Monogenea: Polyopisthocotylea: Diclidophoroidae) from Labeo forskalii. - Proc. Helminthol. Soc. Wash., 30_: GUSSEV, A. V. (1983): Methods for collecting and processing parasitic Monogenea of fish (in Russian). - Publishing House Nauka. Leningrad. HA KY (1968): New species of monogeneans from freshwater fishes of North Vietnam. I. (in Russian). - Parasitologiya, 2: PAPERNA, I. (1961): Studies on monogenetic trematodes in Israel 3. Monogenetic trematodes of Cyprinidae and Claridae of the Lake Galilee. - Bamidgeh, 13: PAPERNA, I. (1965) : Monogenetic trematodes collected from freshwater fish in Southern Ghana. - Bamidgeh, _17: PAPERNA, I. (1968): Onchobdella n. gen. New Genus of monogenetic trematodes (Dactylogyridae, Bychowski, 1933) from Cichlid fish from West Africa. - Proc. Helminthol. Soc. Wash., 35= PAPERNA, I. (1969a): Monogenetic trematodes of the fish of the Volta basin and South Ghana. - Bull. Inst. Fondam, Afr. Noira (A Sei. Nat.), 31: PAPERNA, I. (1969b): Monogenea of the subfamily Heteronchocleidinae, Price, 1968 (Dactylogyridae) from African freshwater fish. - Parasitology, 59: PAPERNA, I. (1973): New species of Monogenea (Vermes) from African freshwater fish. A preliminary report. Rev. Zool. Bot. Afr., jj7: PAPERNA, I. - THURSTON, J. P. (1968): Monogenetic trematodes in Uganda. - Rev. Zool. Bot. Afr., 78: (Dactylogyridae) from fish PAPERNA, I. - THURSTON, J. P. (1969a): Monogenetic trematodes collected from cichlid fish in Uganda: including the description of five new species of Cichlidogyrus. - Rev. Zool. Bot. Afr., 79: PAPERNA, I. - THURSTON, J. P. (1969b): Annulotrema n. gen., a new genus of monogenetic trematodes (Dactylogyridae, Bychowski, 1957) from African characin fish. - Zool. Anz,, 182: Received: 3 June, 1985 Dr. MOLNÁR, K. Veterinary Medical Research Institute, Hungarian Academy of Sciences, P.O. Box 18. H Budapest HUNGARY Dr. MOSSALAM, I. Faculty of Veterinary Medicine University of Zagazig Zagazig EGYPT