NEIHPID

Diplodiscus amphichrus (Tubangui Tubangui) Back

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Taxonomy

Platyhelminthes »
       TREMATODA »
              Digenea »
                     Paramphistomidae Fischoeder, 1901 »
                            Diplodiscinae Cohn, 1904 »
                                   Diplodiscus Diesing, 1836 »
                                           Diplodiscus amphichrus, Tubangui 1933

Synonyms

(D. sinicus Li, 1937; D. amphichrus magnus Srivastava, 1934; D. mehrai Pandey, 1975 nee Pande, 1937)

Host

Chirixalus (vitattus), Polypedates (leucomystax), Rana (Sp.), Rhacophorus (maximus (=R. nigropalmatus))

Habitat

Intestine, Rectum

Locality

Shillong (Meghalaya), Mokokchung (Nagaland)

Description

Body stout, conical, aspinose, tapering anteriorly, border posteriorly, 1.78-3.19 mm in length, 0.84-1.66 mm in maximum width in front of acetabulum. Mouth sub-terminal, followed by fairly well developed, sub-terminal, spherical or oval pharynx (=oral sucker), latter with a pair of pharyngeal (=oral) diverticula arising from its base. Ventral sucker or acetabulum extremely large, conspicuous, cup shaped, located at posterior extremity, provided with an additional sucker with depression in center. Oesophagus long, tubular, dilated posteriorly to form bulb, throughout its course surrounded by oesophageal glands. Intestinal caeca more or less straight, running laterally, extending up to or little in front of anterior border of acetabulum. Testis single, situated roughly horizontally near middle half of body, oval, irregularly notched, pre-ovarian and equatorial; two vasa efferentia arising from antero-lateral border of testis, later uniting to form vesicula seminalis externa. Cirrus sac elongated or sub-globular, containing vesicula seminalis interna, pars prostatica and ejaculatory duct. Genital pore just behind oesophageal bulb or extra-caecal, post-bifurcal. Ovary globular, inter-caecal, to right of median axis. Receptaculum seminis absent. Uterus travelling posteriorly on right side of ovary, on reaching anterior border of acetabulum turning forward to fill most of inter-caecal space, running ventrally to vesicula seminalis externa and circus sac, terminating into thick convoluted metraterm. Vitellaria large, forming compact masses of follicles extending from little distance in front of intestinal bifurcation posteriorly to acetabulum, partly overlapping its anterior border, mainly lateral in position but meeting medially in acetabular part to form a dorsally placed row. Eggs few, large, 0.099-0.113 x 0.05-0.072 mm. Excretory pore dorsal, pre-acetabular.

Remarks

The genus Diplodiscus is well represented among anuran amphibians in India. Many controversies exist in the literature regarding the status of the species described under the genus from India. Tubangui,(1933) described D. amphichrus from Rana sp.in the Philippines. Srivastava (1934) described a new variety of this species D. amphichrus var. magnus from E. cyanophlyctis in Uttar Pradesh and Pande (1937b) added another new species, D. mehrai, from the same host in Kumaon Hills, differentiating it from the earlier known species in the presence of pre-bifurcal genital pore. Singh (1954), considering the position of genital and excretory pores only minor variations, regarded D. amphichrus var. magnus and D. mehrai as synonyms of D. amphichrus. While also suggesting the same, Mukherjee (1966) further synonymised D. japonicus (Yamaguti, 1936) with D. amphichrus. Agrawal (1966, 1968) re- described the latter from Bufo sp.in Lucknow and D.lalli and supported the earlier suggested synonymy. Fischthal and Thomas(1968) raised the variety magnus of Srivastava to species rank and considered that D. amphichrus of Agarwal and Singh,(1979)were synonyms of magnus and so were D. amphichrus japonicus and D. mehrai. Pandey and Chakraborty, (1968) and Pandey (1969) described two new species, D. lalli and D. chauhani from Rana tigrina and R. cyanophlyctis, respectively and Pandey and Jain (1974) upheld the validity of D. mehrai. Nama and Khichi (1973) described a new sub species, D. amphichrus brevis from R. cynophlyctis and disagreed to the synonymy of D. mehrai to D. amphichrus. Srivastava (1982), based on his observations on the material collected from Orissa, suggested that D. lali and D. chauhani are synonymous with D. amphichrus. Srivastava (1982) also considered that the genus is represented by two distinct species D.amphichrus and D.mehrai in India.Â

D. amphichrus appears to have a wide distribution in India. It has been reported from many localities, such as Uttar Pradesh, West Bengal, Maharashtra, Tamil Nadu, Kerala etc. (Agarwal, 1966; Mukherjee and Ghosh, 1972; Nama and Khichi, 1973; Pandey, 1969.) with frogs as its common hosts. From North-East India, D. amphichrus was first reported by Diengdoh (1989) in Meghalaya.

Helminthological collections record

NEHU/Z - TA/6

Specimen Type

Holotype: W7783/1 in Zoological Survey of India, Kolkata.

References

Tubangui, M. A. (1933). Trematode parasites of Philippine Vertebrate. VI. Description of new species and classification. Phillipine Journal of Sciences . 52(2) : pp  167-197

Srivastava, H .D. (1934). On new trematodes of frogs and fishes of the United Provinces, India. Part IV. The occurrence and seasonal incidence of infection of certain trematodes in the above hosts. Bulletin of Academy of  Science U.P.  Agra & Oudh. 4(1):pp 113-119.

Pande, B. P. (1937b). On the morphology and systematic position of a new bladder fluke from an Indian frog. Annals and Magazine of Natural History. 20: pp 250-256.

Singh, K. S. (1954). Some trematodes collected in India, Transactions of American Microscopical Society. 73:pp 202-210.

Mukherjee, R. P. (1966b). On some amphistomes of India. Indian Journal of Helminthology. 28(2):pp  94-103.

Yamaguti, S. (1936). Studies on the helminth fauna of Japan. 14. Amphibian trematodes. Japanese Journal of Zoology .6(4): 551-576.

Agarwal. V. (1966 a) Studies on some trematodes of frogs from Lucknow. Indian Journal of Helminthology. 28 (1):pp 82-90.

Agarwal, V. (1968) Two reptilian trematodes from Lucknow. Annals of

Fischthal, J. H. and Thomas, J.D. (1968). Digenetic trematodes of amphibians and reptiles from Ghana. Proceedings of Helminthological Society of Washington. 35:pp 1-15.

Pandey, K .C. and Chakrabarti , K. K. (1968). On a new trematode Diplodiscus lali n. sp. from the common Indian frog  Rana tigrina Daud. Ceylon Journal of Science (Biological Science). 8:pp 38-41.

Pandey, K. C. (1969). On a new trematode Diplodiscus chauhani n. sp. from the common Indian frog, Rana cyanophlyctis Schneider. Proceedings of Indian Academy of Sciences. 69(4): pp 203-206.

Pandey, K. C. and Jain, K. M. (1974). Diplodiscus mehrai Pande, 1937 from the common apple snail Pila globusa Seainson, at Lucknow. Journal of Zoological Society of India. 26(1-2): 145-147.

Nama, H. S. and Khichi, P. S. (1973). A new trematode and a new nematode from the frog, Rana cyanophlyctis Schneider. Proceedings of  Zoological Society  Calcutta. 26: pp 15-19.

Srivastava, C. B. (1982). The fauna of India and the adjacent countries -- Platyhelminths. Vol. I (Supplement): Trematoda -- Digenea. Zoological Survey of India. pp 163.

Mukherjee, R .P. and Ghosh, R .K. (1972). Studies on some amphibian trematodes from West Bengal and Maharashtra (Part II). Records of Zoological Survey of India. 66:pp 273-276.

Diengdoh, C.R.(1989). Helminth Parasite Spectrum of Amphibian Hosts in Meghalaya. Ph.D. thesis. North-Eastern Hill University (N.E.H.U.) Shillong. pp 129.