Studies on the Structure of Three New Species of Strigeids Metacercariae from Indian Freshwater Food Fishes

Available online at www.ijpab.com Gupta, B.K. Int. J. Pure App. Biosci. 4 (4): 221-228 (2016) ISSN: 2320 – 7051 DOI: http://dx.doi.org/10.18782/2320-7051.2347 ISSN: 2320 – 7051 Int. J. Pure App. Biosci. 4 (4): 221-228 (2016) Research Article

Barrister Kumar Gupta* Department of Zoology, Vardhaman College, Bijnor, 246701, Uttar Pradesh, India *Corresponding Author E-mail: [email protected] Received: 7.08.2016 | Revised: 15.08.2016 | Accepted: 18.08.2016

ABSTRACT The author extensively studied on digenetic trematode larvae of Indian freshwater food fishes during research tenure. Three new species of strigeid metacercariae belonging to genus Neascus Hughes14, 1927 and Tetracotyle Faust10, 1918 were collected from Anabas testudineus, Channa punctatus and Xenentodon cancilla and named Neascus kaisarbaghensis, Tetracotyle bhopalensis and Tetracotyle mauensis from different location respectively.

Key words: Metacercaria, Neascus, Tetracotyle, Strigeids, Trematode.

INTRODUCTION million people suffer from insecure food India is the seventh largest country in the supplies and malnutrition globally. The Pattern world and Asia's second largest nation. It and determinants of inadequate nutrition are contains a great wealth of biological diversity. changing. People world over faces interrelated As we know that over half of all vertebrates, malnutrition burden leads to under-nutrition, are fishes (Approx.11.7%, 2546 Indian sp. out and micronutrient deficiencies. To push the of 21,730 world sp.). Fish provides nutritious sustainable development agenda as per the food and are important source of fresh animal United Nations in case of food, nutrition and proteins. But almost all fishes carry infections environmental security such research fills the of adult trematodes or metacercariae. They lacunae hence my commitment is to work on infect all the body parts and cause diseases it. thus reducing their food value. In case of heavy infections, mortality is also caused, MATERIAL AND METHODS which in turn is a great loss to fish industry. During study here fish specimens were They can also transfer infections to man when collected from different water bodies of India infected with trematodes larvae i.e. especially north India including Eastern U.P., metacercariae. They are dangerous parasites, and Jhansi, with the help of fishermen or primarily of carps and siluroids, causing purchased from the fish markets. massive epizootics. Currently about 800

Cite this article: Gupta, B.K., Studies on the Structure of Three New Species of Strigeids Metacercariae from Indian Freshwater Food Fishes, Int. J. Pure App. Biosci. 4(4): 221-228 (2016). doi: http://dx.doi.org/10.18782/2320-7051.2347

Gupta, B.K. Int. J. Pure App. Biosci. 4 (4): 221-228 (2016) ISSN: 2320 – 7051 Fishes were identified by Fish Base11. and opens outside terminally through an Trematode metacercariae were isolated from excretory pore, at hind body region. Two main various parts of their hosts namely Anabas collecting canals of reserve excretory system testudineus, Channa punctatus and originate, one of each side, from cornua of Xenentodon cancila (especially Kaisarbagh, excretory bladder, run through lateral body Bhopal and Mau respectively). Larval margins upto level of pharynx where they trematodes were identified in live conditions unite with each other by an anterior transverse under binocular microscope and observed canal. A median reserve excretory canal under a phase-contrast microscope. A few originates from anterior transverse canal, runs specimens of each worms were fixed in posteriorly upto holdfast organ and joins formalin- alcohol- acetic acid (FAA) (2:17:1) posterior transverse canal which further opens under light pressure and stained overnight in into two main canals. Two lateral canals, on an Aceto-carmine, whole mounts were made for each side of median canal also originate from taxonomic study. anterior transverse canal, runs upto holdfast organ and form posterior transverse canal. RESULT Two median longitudinal canals, originate at Neascus kaisarbaghensis n. sp. junction of fore and hind body. These major Host: Anabas testudineus (Bl.) canals are joined together by short transverse Site of infection/Location: Cranium/Branchial canals but their arrangement could be observed region in detail. Small, black, excretory corpuscles Locality: Kaisarbagh fish market, Lucknow flow freely in canals. No. of host examined: 05 No. of host found infected: 02 DISCUSSION No. of metacercariae collected: 07 The Indian species of strigeid metacercariae of Description: Cyst (Fig.1) oval, transparent, group Neascus14 are N. vetastai17, N. chelai18, 1.13 - 1.33 mm x 0.90 - 1.20 mm. Body N. indicus32, N. cirrhinus32, N. elongates29,30, (Fig.2) aspinose, foliaceous, well N. hepatica9, N. channi26, N. xenentodoni26, N. differentiated into fore and hind body, fore komiyai Pandey28, N. hoffmani28, N. gussevi8, body 0.47 - 1.03 mm x 0.19 – 0.21 mm and N. nanaksagrensis5, N. chauhani3, N. hind body 0.19 - 0.22 mm x 0.13 - 0.19 mm. hanumanthai3, N. simhai3, N. moghei3, N. Oral sucker terminal, 0.03 - 0.04 mm x 0.02 - shahjahanpurensis23, N. ramalingami23, N. 0.03 mm. Ventral sucker smaller than oral vedi23 and N. bhopalensis13 & N. sucker, elongate-oval, 0.03 - 0.04 mm x 0.02 - dohrighatensis13. The present larva closely 0.03 mm. Pharynx absent. Intestinal caeca resembles with N. vetastai, N. hepatica, N. reaching upto posterior end of hind body. Hold xenentodoni, N. hoffmani, N. hanumanthai, N. fast organ strongly developed, situated behind simhai, N. moghei, N. ramalingami and N. vedi ventral sucker, 0.13 - 0.15 x 0.17 - 0.20 mm. in shape of body and number of genital Hold fast gland bilobed, transversely rudiments but differs from them in shape of elongated, located behind holdfast organ, 0.28 holdfast organ and holdfast gland. It further - 0.30 mm x 0.02 - 0.04 mm. Gonads differs from N. vetastai, N. xenentodoni, N. represented by three dark stained cell masses; hoffmani, N. simhai and N. moghei in ratio of two large masses appear to be testes, 0.02 - suckers, from N. hepatica and N. vedi in ratio 0.07 mm x 0.06 - 0.12 mm and 0.02 - 0.08 mm of fore and hind body, from N. hanumanthai x 0.10 - 0.16 mm and one small elongated and N. ramalingami in absence of pharynx. mass in between two testes, 0.01 - 0.03 mm x Besides this it differ from N. bhopalensis13, 0.05 - 0.09 mm, could be future ovary. 2015 in ratio of suckers, presence of Copulatory bursa, oval and located in hind esophagus & intestinal caeca and shape of body. Excretory bladder (Fig.3) ‘V’ shaped holdfast organ holdfast gland and lastly from Copyright © August, 2016; IJPAB 222

Gupta, B.K. Int. J. Pure App. Biosci. 4 (4): 221-228 (2016) ISSN: 2320 – 7051 N. dohrighatensis13, 2015 in ratio of sucker, present. Genital rudiment represented by two ratio of fore and hind body, shape of genital tandem, elongated cell masses, at hind region rudiments and pattern of reserve excretory of body. Excretory bladder (Fig.6) ‘V’ shaped, systems. located at posterior end of body, opening Among the species described from foreign outside by terminal excretory pore. Main land, it comes closer to Neascus of reserve excretory canals, one on each lateral Ornithodiplostomum ptychocheilus, Neascus side, run anteriorly upto pseudosuckers and of Posthodiplostomum minimum, Neascus of join fellow canal by a transverse canal. A Posthodiplostomum cuticola, Neascus grandis, median excretory canal, runs posteriorly, in Neascus rhinichthysi, Neascus ellipticus, and median region of body, upto gonads and joins Neascus pyriformis in shape of body but main canal. Canals are filled with free floating, differs in absence of pharynx and ratio of round to oval corpuscles. body. It further differs from Neascus grandis, Neascus pyriformis and Neascus ellipticus in DISCUSSION number of genital rudiments, from Neascus of To the best of my knowledge, the following Ornithodiplostomum ptychocheilus, Neascus species of metacercariae are known under of Posthodiplostomum minimum and Neascus strigeid group Tetracotyle10 from India viz. T. of Posthodiplostomum cuticola in ratio of ranae17, T. sophorensis31, T. indicus31, T. suckers and from Neascus rhinichthysi in ujjainensis33, T. szidati7, T. xenentodoni6, T. shape of holdfast organ and holdfast gland. aglandulata5, T. muscularis6, T. glossogobii6, Therefore, the larva is regarded a new species T. lali29, T. lucknowensis25, T. singhi27, T. and named Neascus kaisarbaghensis n. sp. baughi27, T. tandani27, T. bufoi2, T. lymnaei21, after the locality wherefrom the host was T. gyanpurensis4, T. pandei1, T. srivastavi1, T. procured. ramalingi1, T. simhai24, T. sanjivi 24, T. 24 20 22 fotedari , T. kawi , T. kalyani , T. Tetracotyle bhopalensis n. sp. satyapalii22, and T. multilobulata12 & T. Host: Channa punctatus (Bloch) madhubanensis12. Of the above species, the Location: Gut present larva closely resembles with T. ranae, Locality: Fish market, Bhopal T. indicus, T. ujjainensis, T. lali, T. singhi, T. No. of host examined: 20 gyanpurensis, and T. satyapali in position of No. of host found infected: 05 pseudosuckers and holdfast organ but differs No. of metacercaria collected: 10 from them in the number of genital rudiments Description: Cyst (Fig.4) oval, thin, transparent, 1.02 - 1.05 which is two in the present larva. It further mm x 0.66 - 0.68 mm. Body (Fig.5) elongated, differs from T. indicus, T. singhi, and T. aspinose, 1.25 - 1.27 mm x 0.63 - 0.64 mm. satyapalii, T. ujjainensis and T. gyanpurensis Suckers well developed and muscular. Oral in the shape of holdfast organ, and from T. sucker sub-terminal, more or less circular, 0.10 ranae and T. lali in shape of body which is mm - 0.11 mm. Ventral sucker pre-equatorial, elongate-oval. Besides this the present larva larger than oral sucker, 0.11 - 0.12 mm x 0.12 differ from T. multilobulata in ratio of sucker, - 0.13 mm. Prepharynx absent. Pharynx shape & position of pseudosuckers, absence of elongate-oval, 0.04 - 0.05 mm x 0.04 - 0.06 esophagus and intestinal caeca, shape of mm. Pseudo-suckers situated on each side of holdfast organ and holdfast gland and number intestinal bifurcation, 0.15 - 0.17 mm x 0.09 - and shape of genital organ. While from T. 0.10 mm. Hold fast organ well developed, 0.36 madhubanensis the present larva differs in - 0.38 mm x 0.21 - 0.27 mm, elongate, 3 lobed, ratio of suckers, shape and position of with a distinct ‘U’ shaped cavity. A ‘U’ pseudosuckers, absence of esophagus and shaped holdfast gland, behind holdfast organ intestinal caeca, shape of holdfast organ and Copyright © August, 2016; IJPAB 223

Gupta, B.K. Int. J. Pure App. Biosci. 4 (4): 221-228 (2016) ISSN: 2320 – 7051 holdfast gland, number of genital rudiments shaped. Inner and outer longitudinal canals are and pattern of reserve excretory system. joined in region of pseudo-suckers. 9 - 11 Among the species described from foreign transverse canaliculae join to outer 15 land, it differs from Tetracotyle diminuta , in longitudinal canals. Reserve excretory system ratio of sucker and position of pseudosuckers, filled with round excretory corpuscles. Tetracotyle of Apatemon fuligulae Yamaguti, DISCUSSION 1933 and Tetracotyle of Apatemon pellucidus The present larva closely resembles with T. Yamaguti, 1933 in shape of body, absence of glossogobii, T. lucknowensis, T. kawi, T. prepharynx, esophagus and intestinal caeca, from Tetracotyle of Cotyluris communis sanjivi, T. pandei and T. satendri in shape of Hughes, 1928, Tetracotyle biwaensis body and shape and position of pseudosuckers Yamaguti, 1942 and Tetracotyle tahoensis but differs from them in ratio of suckers. It Haderlie, 1953 in number of genital rudiments, chiefly differs from T. glossogobii, T. shape of holdfast organ and holdfast glands. lucknowensis, T. sanjivi, T. pandei and T. Therefore, the larva is regarded new to science satendri in the number of genital rudiments, and named T. bhopalensis n. sp. after the from T. kawi in shape of holdfast organ and locality where from the host was obtained. holdfast gland. It also differs from T. bhopalensis n. sp. described in earlier pages, in Tetracotyle mauensis n. sp. shape, size and position of pseudosuckers, and Host: Xenentodon cancila (Ham.) also in the number of genital rudiments. Location: Liver/Gut Besides this the present larva differ from T. Locality: Mau (U.P.) multilobulata in ratio of sucker, shape & No. of host examined: 18 position of pseudosuckers, presence of No. of host found infected: 02 esophagus and intestinal caeca, shape and No. of metacercaria collected: 05 position of holdfast organ and holdfast gland Description: and number, position and shape of genital Cyst (Fig.7) oval, thick, 1.22 - 1.24 mm x 0.75 organ. It also differ from T. madhubanensis in - 0.76 mm., two layered, outer layer thick, ratio of suckers, shape and position of fibrous, tough, pigmented and inner layer thin, pseudosuckers, absence of pharynx, shape and transparent. Body (Fig.8) undivided, aspinose, position of holdfast organ and holdfast gland, with narrow anterior and broad posterior ends, number and shape of genital rudiments and in 0.33 - 0.43 mm x 0.24 - 0.29 mm. Oral sucker pattern of reserve excretory system. 0.09 - 0.11 mm x 0.09 - 0.10 mm. Ventral Among the species described from foreign land, it comes closer to Tetracotyle of sucker smaller than oral sucker, 0.04 - 0.05 Cotyluris communis, T. diminuta, Tetracotyle mm x 0.04 - 0.05 mm. Pseudo-suckers large, of Apatemon pellucidus, Tetracotyle biwaensis muscular, somewhat triangular, located at and Tetracotyle tahoensis by the absence of lateral sides of pharynx, 0.09 - 0.15 mm x 0.09 prepharynx and position of pseudosuckers but - 0.10 mm. Esophagus and intestinal caeca not differs in shape of holdfast organ and holdfast visible. Hold-fast organ well developed, pear gland. It further differs from Tetracotyle of shape, posterior to ventral sucker, having a Cotyluris communis, T. diminuta, Tetracotyle distinct cavity. A dark mass of cells, biwaensis and Tetracotyle tahoensis in representing holdfast gland, at hind end of absence of esophagus and intestinal hold fast organ present. Genital rudiment, bifurcation and ratio of suckers, from represented by an elongate-oval, dark stained Tetracotyle of Apatemon fuligulae in absence cell mass at hind region of body, overlap the of prepharynx and shape of holdfast organ and holdfast gland. Excretory bladder (Fig.9) ‘V’ holdfast gland and from Tetracotyle of Copyright © August, 2016; IJPAB 224

Gupta, B.K. Int. J. Pure App. Biosci. 4 (4): 221-228 (2016) ISSN: 2320 – 7051 Apatemon pellucidus in the presence of Tetracotyle mauensis n. sp. after the locality pharynx and ratio of body. Therefore, the larva wherefrom the host was procured. is regarding as new to science and named

Gupta, B.K. Int. J. Pure App. Biosci. 4 (4): 221-228 (2016) ISSN: 2320 – 7051

Fig. 1, 4, 5 Encysted metacercariae Fig.2, 5, 8 metacercariae Fig.3, 6, 9 metacercariae, showing reserve excretory system (drawn from live specimens)

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