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A survey of didymozoid trematodes of the barracuda Sphyraena obtusata from Kuwait Bay
InrernarionolJournal/or Parasitolo~_y Vol. 23, No. 5, pp. 665-669, 1993 Printed m Grear Briram 6
002&7519/93 $6.00 + 0.00 Pergomon Press Lid I993 Ausrralim Society/or Porosmlog?:
RESEARCHNOTE A SURVEY
OF DIDYMOZOID TREMATODES OF THE BARRACUDA SPHYRAENA OBTUSATA FROM KUWAIT BAY J. ABDUL-SALAM Department
of Zoology,,
University
and B. S. SREELATHA
of Kuwait,
P.O. Box 5969, Safat, Kuwait
13060
(Received 23 February 1993; accepted 3 May 1993)
Abstract-ABowL-SALAM J. and SREELATHA B. S. 1993. A survey of didymozoid trematodes of the barracuda Sphyraena obtusata Cuvier from Kuwait Bay. International Journal for Parasitology 23: 665669. Examination of 120 yellow-fibned barracudas, Sphyraena obtusata, from Kuwait Bay revealed 8 species of didymozoid trematodes encapsulated in pairs in the tissues. Four species of the didymozoids, Allodidymozoon operculare, Didymocylindrus sp., Didymocystis sp., and Didymocystoides sp., were found in the head region, 3 species, C)idymoroon tetragynae, Lepidodidymozoon sinicum and Platocystoides polyaster, in external surfaces and 1 specks, Allodidymozoon sp., in stomach wall. The didymozoid species collected constitute new geographic distribution records and occurrence of D. tetragynae and L. sinicum are new host records. INDEX
KEY WORDS:
Digenea;
Didymozoidae;
Kuwait
ADULT trematodes of the family Didymozoidae (Poche, 1907) are recorded in more than I!0 fish species representing 32 families in tropical and subtropical waters (Nikolaeva, 1985). In contrast to other trematodes, didymozoids are usually found encapsulated in tissues or body cavity of the host species rather than free in the lumen of the various organs. Although many surveys have been conducted on the didymozoid fauna of the various geographic regions of the Indo-West Pacific waters, no work as such has been done in the Arabian Gulf with the exception of description of an adult and a larval didymozoid species by Abdul-Salam, Sreelatha & Farah (1990a, b). The tissues of 120 barracudas, S. obtusata, between 20 and 30 cm in length, were examined for didymozoid trematodes. The fish were caught by line fishing or netting, in Kuwait Bay, northern Arabian Gulf from February through May 1992. Didymozoids were teased out of host tissue, fixed in acetic acidformalin-alcohol and stored in 70% ethanol. Representative specimens of each didymozoid species collected were stained with Harris’ haematoxylin and permanent slides were prepared for identification purposes. Didymozoids species were tentatively keyed according to Yamaguti (1971) in conjunction with descriptions from the literature. Representative specimens of each didymozoid species recovered were deposited in the helminthological collection of the Department of Zoology, University of Kuwait.
Bay; fish trematodes;
Sphyraena obtusata.
The 120 S. obtusata examined harboured 8 species of adult digenetic trematodes. The occurrence of the trematodes in pairs in the tissues of a marine fish and the general features of their anatomy place them in the family Didymozoidae Poche 1907, subfamily Didymozoinae (Ishii, 1935) as defined by Yamaguti (1971). Didymozoines morphology is characterised by two prominent regions; a slender forebody containing the anterior portion of the digestive tract and terminal genital ducts, and a broader elongate hindbody which may be globular, cylindrical or lobular, containing reproductive organs, the posterior portion of intestine and excretory vesicle. Light micrographs of the didymozoid species collected are shown in Figs. 1-8. Table 1 lists site, prevalence and intensity of infection of each species. Of the total barracudas, 70.0% (84) were infected with at least one species of didymozoid. The number of didymozoid species per infected fish varied from 1 to 6 (mean 2.5). Allodidymozoon operculare and Lepidbdidymozoon sinicum were the most commonly occurring didymozoid species found in 60.8 and 43.3% of the barracudas, respectively. Didymozoid larvae were also common in tissues of the barracudas, particularly in stomach wall and skin scrapings. Several species of didymozoines have been recorded from barracudas from the Indian (Job, 1961a; 1961b; 1962; 1964; 1966; Madhavi, 1982) and western Pacific Oceans (Yamaguti, 1959; Gu & Shen,
665
666
1
Research
Note
FIGS. 5-6. FIGS. 1-8. Light micrographs of didymozoid trematodes from the barracuda Sphyraena obrusafa from Kuwait Bay. (1) Allodidymozoon operculare. Scale bar = 0.3 mm. (2) Allodidymozoon sp. Scale bar = 1.0 mm. (3) Didymocylindrus sp. Scale bar = 0.6 mm. (4) Didymocystis sp. Scale bar = 1.1 mm. (5) Didymocystoides sp. Scale bar = 1.0 mm. (6) Didymozoon tetragynue. Scale bar = 0.3 mm. (7) Lepidodidymozoon sinicum. Scale bar = 0.5 mm. (8) Platocystoidespolyaster. Scale bar = 1.O mm.
J. ABDUL-SALAM and B. S. SREELATHA
668 TABLE I-SITE
01. INFECTION. PREVALENCE AND INTENSITY OF DIDYMOZOIDTREMA~ODESIN
120 YELLOW-FINNED BARRACUDAS
Sphyraena obtusata CUVIERFROMKUWAIT BAY
Didymozoid species
Site of infection
Prevalence (X)
Intensity (mean)
Allodidymozoon operculare Madhavi, 1982 Aiiodi~~mozoon sp. Yamaguti, 1959 Didymocylindrus sp. Ishii, 1935 Didymocysiis sp. Ariola, 1902 Didymocystoides sp. Yamaguti. 1970 Didymozoon tatrag_vnae Job. 1961 Lepidodidymozoon sinicum Shen. 1984 Platocystoides polyaster Job, 1962
Head muscles Stomach muscle Pharyngeal muscle Opercular
60.8
l-9 (5.1)
30.0
I-1
(Forskal)
from
grouper
(Abdul-Salam
Epinephelus
et a/.. 1990a).
3.3
l-2 (2.1)
6.1
l-2 (4.3)
13.3
IL2 (2.3)
31.7
5-25 (9.0)
43.3
3-12 (1.8)
Il.7
2-8 (1.3)
muscle Head muscles Between fin rays Under the skin Beneath scales
1965; Shen, 1984). Barracudas from Kuwait Bay harboured 3 species of didymozoids, A. operculare, Didymozoon tetragynae and Platocystoides polyaster, found in the Indian Ocean and 1 species, L. sinicum, found in the Pacific Ocean while the remaining 4 species appear to be new. Although the life histories of didymozoids are not completely known, it would seem that the reported variation in species composition is probably due to barracudas utilizing different intermediate hosts as food items in each locality. As suggested by Nikolaeva (1965), fish probably acquire didymozoids by ingesting infected planktonic invertebrates or small fishes, potential paratenic hosts. The high intermediate or prevalences, intensities and species diversity of didymozoids recorded in barracudas from Kuwait Bay reflect favourable physical and biological conditions for the propagation of didymozoid life cycle. The Bay is known for its high nutrient loads due to organic enrichment from Shatt Al Arab. The combination of nutrient enrichment and mild temperature and salinity regimes increases the productivity of the Bay (Clayton, 1986) which in turn increases the numbers of potential intermediate and paratenic hosts for didymozoids. new All didymozoids collected constitute geographic distribution records for the Arabian Gulf and occurrences of D. tetragynae and L. sinicum are new host records. The only other adult didymozoid reported from this region is Gonapodasmius epinepheli
I (3.5)
tauvinu
REFERENCES ABDUL-SALAM J., SREELATHA B. S. & FARAH M.
1990a.
Gonapodasmius epinepheli n. sp. (Didymozoidae) from the grouper Epinephelus tauvina from the Arabian Gulf. Systematic Parasitology 17: 67-14. ABDUL-SALAM J., SREELATH~ B. S. & FARAH M. 1990b. Surface topography and description of a larval Didymozoid (Trematoda, Didymozoidae) from the threadfin bream Nemipterus peronii. Japanese Journal of Parasitology 31: 369-375. CLAYTON D. A. 1986. Ecology of mudflats with particular reference to those of the northern Arabian Gulf. In: Marine Environment and Pollution (Edited by HALWAG\ R., CLAwoN D. & BEHBEHANIM.). pp. 83-96. Kuwait University. Gv C. & SHEN J. 1965. Taxonomic study on the family Didymozoidae Poche, 1907 (Trematoda) from some marine fishes in China. Acta Scientiarum Naturalinunr Universitatis Nan Kaiensis 6: 2148. IWII N. 1935. Studies on the family Didymozmdae (Monticelli, 1888). Japanese Journal of Zoology 6: 279-~ 335. JOB S. V. 196la. Didymomozoon tetragynac: a digenetic trematode of the family Didymozoidae. Journal of the Madras University 31: 3 1 l-3 14. JOB S. V. 196lb. New record of a digenetic trematode of the family Didymozoidae. Prcsrdenc~~, Co/&, %oolo~~~ Magazine 8: 12- 14. JOB S. V. 1962. A new record of a dlgenetic trematode of the genus Platocystis (Family: Didymozotdae). Journal o/ /hc Zoological Society of India 13: 143%147. Joe S. V. 1964. Description of a new species of digenetic trematode (Fam: Didymozoidae) and some histochemical observations on the same. Proceedings of’ the Indiun Academy of’Science.v 60: 128-I 34.
Research JOB S. V. 1966. Didymoeystis sin&a& n. sp. a digenetic trematode from barracuda. Zoolo~~sc~~r Anzeiger 177: 316318. MADHAVI R. 1982. Didymozoid trematodes (in&ding new genera and species) from marine fishes of the Waltair Coast, Bay of Bengal. Systematic Parasitology 4: 99-124. NIKOLAEVAV. M. 1965. The life cycle of trematodes of the family Didymozoidae (Monticelli, 1888) Poche, 1907. Zoologicheskii Zhurnal44: I3 17-I 327. [In Russian.] NIKOLAEVAV. M. 1985. Trematodes-Didymozoidae fauna, distribution and biology. In: Parasitology and Pathology
Note
669
of Marine Organisms of the World &ear2 (Edited by HARGIS W. J.), pp. 67-72. National Oceanic and Atmospheric Administration, Seattle, U.S.A. SHEN J. 1984. Digenetic trematodes of Didymozoidae Poche, 1907 from marine fishes in the East China Sea. Studia Marina Sinica 23: 121-129. YAhiAcrirl S. 19.59. Studies on the helminth fauna of Japan. Part 54. Trematodes of fishes XIII. Publications of the Seto Marine Biological Laboratory 7: 241-262. YAMAGUTI S. 1971. Synopsis of Digenetic Trematodes of Vertebrates. Keigaku Publishing Company, Tokyo.
002&7519/93 $6.00 + 0.00 Pergomon Press Lid I993 Ausrralim Society/or Porosmlog?:
RESEARCHNOTE A SURVEY
OF DIDYMOZOID TREMATODES OF THE BARRACUDA SPHYRAENA OBTUSATA FROM KUWAIT BAY J. ABDUL-SALAM Department
of Zoology,,
University
and B. S. SREELATHA
of Kuwait,
P.O. Box 5969, Safat, Kuwait
13060
(Received 23 February 1993; accepted 3 May 1993)
Abstract-ABowL-SALAM J. and SREELATHA B. S. 1993. A survey of didymozoid trematodes of the barracuda Sphyraena obtusata Cuvier from Kuwait Bay. International Journal for Parasitology 23: 665669. Examination of 120 yellow-fibned barracudas, Sphyraena obtusata, from Kuwait Bay revealed 8 species of didymozoid trematodes encapsulated in pairs in the tissues. Four species of the didymozoids, Allodidymozoon operculare, Didymocylindrus sp., Didymocystis sp., and Didymocystoides sp., were found in the head region, 3 species, C)idymoroon tetragynae, Lepidodidymozoon sinicum and Platocystoides polyaster, in external surfaces and 1 specks, Allodidymozoon sp., in stomach wall. The didymozoid species collected constitute new geographic distribution records and occurrence of D. tetragynae and L. sinicum are new host records. INDEX
KEY WORDS:
Digenea;
Didymozoidae;
Kuwait
ADULT trematodes of the family Didymozoidae (Poche, 1907) are recorded in more than I!0 fish species representing 32 families in tropical and subtropical waters (Nikolaeva, 1985). In contrast to other trematodes, didymozoids are usually found encapsulated in tissues or body cavity of the host species rather than free in the lumen of the various organs. Although many surveys have been conducted on the didymozoid fauna of the various geographic regions of the Indo-West Pacific waters, no work as such has been done in the Arabian Gulf with the exception of description of an adult and a larval didymozoid species by Abdul-Salam, Sreelatha & Farah (1990a, b). The tissues of 120 barracudas, S. obtusata, between 20 and 30 cm in length, were examined for didymozoid trematodes. The fish were caught by line fishing or netting, in Kuwait Bay, northern Arabian Gulf from February through May 1992. Didymozoids were teased out of host tissue, fixed in acetic acidformalin-alcohol and stored in 70% ethanol. Representative specimens of each didymozoid species collected were stained with Harris’ haematoxylin and permanent slides were prepared for identification purposes. Didymozoids species were tentatively keyed according to Yamaguti (1971) in conjunction with descriptions from the literature. Representative specimens of each didymozoid species recovered were deposited in the helminthological collection of the Department of Zoology, University of Kuwait.
Bay; fish trematodes;
Sphyraena obtusata.
The 120 S. obtusata examined harboured 8 species of adult digenetic trematodes. The occurrence of the trematodes in pairs in the tissues of a marine fish and the general features of their anatomy place them in the family Didymozoidae Poche 1907, subfamily Didymozoinae (Ishii, 1935) as defined by Yamaguti (1971). Didymozoines morphology is characterised by two prominent regions; a slender forebody containing the anterior portion of the digestive tract and terminal genital ducts, and a broader elongate hindbody which may be globular, cylindrical or lobular, containing reproductive organs, the posterior portion of intestine and excretory vesicle. Light micrographs of the didymozoid species collected are shown in Figs. 1-8. Table 1 lists site, prevalence and intensity of infection of each species. Of the total barracudas, 70.0% (84) were infected with at least one species of didymozoid. The number of didymozoid species per infected fish varied from 1 to 6 (mean 2.5). Allodidymozoon operculare and Lepidbdidymozoon sinicum were the most commonly occurring didymozoid species found in 60.8 and 43.3% of the barracudas, respectively. Didymozoid larvae were also common in tissues of the barracudas, particularly in stomach wall and skin scrapings. Several species of didymozoines have been recorded from barracudas from the Indian (Job, 1961a; 1961b; 1962; 1964; 1966; Madhavi, 1982) and western Pacific Oceans (Yamaguti, 1959; Gu & Shen,
665
666
1
Research
Note
FIGS. 5-6. FIGS. 1-8. Light micrographs of didymozoid trematodes from the barracuda Sphyraena obrusafa from Kuwait Bay. (1) Allodidymozoon operculare. Scale bar = 0.3 mm. (2) Allodidymozoon sp. Scale bar = 1.0 mm. (3) Didymocylindrus sp. Scale bar = 0.6 mm. (4) Didymocystis sp. Scale bar = 1.1 mm. (5) Didymocystoides sp. Scale bar = 1.0 mm. (6) Didymozoon tetragynue. Scale bar = 0.3 mm. (7) Lepidodidymozoon sinicum. Scale bar = 0.5 mm. (8) Platocystoidespolyaster. Scale bar = 1.O mm.
J. ABDUL-SALAM and B. S. SREELATHA
668 TABLE I-SITE
01. INFECTION. PREVALENCE AND INTENSITY OF DIDYMOZOIDTREMA~ODESIN
120 YELLOW-FINNED BARRACUDAS
Sphyraena obtusata CUVIERFROMKUWAIT BAY
Didymozoid species
Site of infection
Prevalence (X)
Intensity (mean)
Allodidymozoon operculare Madhavi, 1982 Aiiodi~~mozoon sp. Yamaguti, 1959 Didymocylindrus sp. Ishii, 1935 Didymocysiis sp. Ariola, 1902 Didymocystoides sp. Yamaguti. 1970 Didymozoon tatrag_vnae Job. 1961 Lepidodidymozoon sinicum Shen. 1984 Platocystoides polyaster Job, 1962
Head muscles Stomach muscle Pharyngeal muscle Opercular
60.8
l-9 (5.1)
30.0
I-1
(Forskal)
from
grouper
(Abdul-Salam
Epinephelus
et a/.. 1990a).
3.3
l-2 (2.1)
6.1
l-2 (4.3)
13.3
IL2 (2.3)
31.7
5-25 (9.0)
43.3
3-12 (1.8)
Il.7
2-8 (1.3)
muscle Head muscles Between fin rays Under the skin Beneath scales
1965; Shen, 1984). Barracudas from Kuwait Bay harboured 3 species of didymozoids, A. operculare, Didymozoon tetragynae and Platocystoides polyaster, found in the Indian Ocean and 1 species, L. sinicum, found in the Pacific Ocean while the remaining 4 species appear to be new. Although the life histories of didymozoids are not completely known, it would seem that the reported variation in species composition is probably due to barracudas utilizing different intermediate hosts as food items in each locality. As suggested by Nikolaeva (1965), fish probably acquire didymozoids by ingesting infected planktonic invertebrates or small fishes, potential paratenic hosts. The high intermediate or prevalences, intensities and species diversity of didymozoids recorded in barracudas from Kuwait Bay reflect favourable physical and biological conditions for the propagation of didymozoid life cycle. The Bay is known for its high nutrient loads due to organic enrichment from Shatt Al Arab. The combination of nutrient enrichment and mild temperature and salinity regimes increases the productivity of the Bay (Clayton, 1986) which in turn increases the numbers of potential intermediate and paratenic hosts for didymozoids. new All didymozoids collected constitute geographic distribution records for the Arabian Gulf and occurrences of D. tetragynae and L. sinicum are new host records. The only other adult didymozoid reported from this region is Gonapodasmius epinepheli
I (3.5)
tauvinu
REFERENCES ABDUL-SALAM J., SREELATHA B. S. & FARAH M.
1990a.
Gonapodasmius epinepheli n. sp. (Didymozoidae) from the grouper Epinephelus tauvina from the Arabian Gulf. Systematic Parasitology 17: 67-14. ABDUL-SALAM J., SREELATH~ B. S. & FARAH M. 1990b. Surface topography and description of a larval Didymozoid (Trematoda, Didymozoidae) from the threadfin bream Nemipterus peronii. Japanese Journal of Parasitology 31: 369-375. CLAYTON D. A. 1986. Ecology of mudflats with particular reference to those of the northern Arabian Gulf. In: Marine Environment and Pollution (Edited by HALWAG\ R., CLAwoN D. & BEHBEHANIM.). pp. 83-96. Kuwait University. Gv C. & SHEN J. 1965. Taxonomic study on the family Didymozoidae Poche, 1907 (Trematoda) from some marine fishes in China. Acta Scientiarum Naturalinunr Universitatis Nan Kaiensis 6: 2148. IWII N. 1935. Studies on the family Didymozmdae (Monticelli, 1888). Japanese Journal of Zoology 6: 279-~ 335. JOB S. V. 196la. Didymomozoon tetragynac: a digenetic trematode of the family Didymozoidae. Journal of the Madras University 31: 3 1 l-3 14. JOB S. V. 196lb. New record of a digenetic trematode of the family Didymozoidae. Prcsrdenc~~, Co/&, %oolo~~~ Magazine 8: 12- 14. JOB S. V. 1962. A new record of a dlgenetic trematode of the genus Platocystis (Family: Didymozotdae). Journal o/ /hc Zoological Society of India 13: 143%147. Joe S. V. 1964. Description of a new species of digenetic trematode (Fam: Didymozoidae) and some histochemical observations on the same. Proceedings of’ the Indiun Academy of’Science.v 60: 128-I 34.
Research JOB S. V. 1966. Didymoeystis sin&a& n. sp. a digenetic trematode from barracuda. Zoolo~~sc~~r Anzeiger 177: 316318. MADHAVI R. 1982. Didymozoid trematodes (in&ding new genera and species) from marine fishes of the Waltair Coast, Bay of Bengal. Systematic Parasitology 4: 99-124. NIKOLAEVAV. M. 1965. The life cycle of trematodes of the family Didymozoidae (Monticelli, 1888) Poche, 1907. Zoologicheskii Zhurnal44: I3 17-I 327. [In Russian.] NIKOLAEVAV. M. 1985. Trematodes-Didymozoidae fauna, distribution and biology. In: Parasitology and Pathology
Note
669
of Marine Organisms of the World &ear2 (Edited by HARGIS W. J.), pp. 67-72. National Oceanic and Atmospheric Administration, Seattle, U.S.A. SHEN J. 1984. Digenetic trematodes of Didymozoidae Poche, 1907 from marine fishes in the East China Sea. Studia Marina Sinica 23: 121-129. YAhiAcrirl S. 19.59. Studies on the helminth fauna of Japan. Part 54. Trematodes of fishes XIII. Publications of the Seto Marine Biological Laboratory 7: 241-262. YAMAGUTI S. 1971. Synopsis of Digenetic Trematodes of Vertebrates. Keigaku Publishing Company, Tokyo.