STUDIES ON THE GENUS GANEO KLEIN, 1905 (TREMATODA

Kloin (1905) proposed the genus Galleo with G. glottoides as the type species obtained from a frog, Rana hexadactyla from Tamil Nadu, India. He tentatively placed this genus under subfamily Pleurogenetinae Looss (1899). Odhner (1911) discussed its systematic position and assigned this genus to the subfamily Pleurogenetinae of the family Leclthodendriidae. Since the description of G. glottoides by Klein, G. glotlo;cles var. africana Skrjabin (1922), G. tigrinum Mehra & Negi (1928), G. giotlo;des var. madrasensis Mehra ~ Negi (1928), G. gastlicus Srivastava (1933), G. attelluatum Srivastava (1933), G. korkei Bha]erao (1936), G. kllmaonensis Pande (1937), G. lingnanensis Li (1938), G. Iri1lllgarensis Kaw (1950), G. gobindiu Dayal & Gupta (1953), G. panjabensis Gupta, N. K. (1954), G. bufonis fotedar (1959) and G. ga=ipurmsu Pandey & Chakrabarti (1968) have been added to the genus Ganeo. Some workers have also extended the distribution of certain species.

Genus Ganeo Klein, 19051905. Ganeo Klein,Zool. Jahrb. Syst.,pI. 41,fig. 50S. In differentiating the species of the genus Ganeo various authors ave used different characters. Some workers have considered certain 8haracters as variations rather thall' of any specific value. A short rc-IU1De of earlier workers follows.
Records of the Zoologlcal Survey 0/ India Skrjabin (1922) does not consider the eJ(itension of intestinal caoca of any specific value. Mehra and Negi (1928) do not consider the dIfference in the position of gonads of any importance because of the variations in the arrangement of gonads in G. glottoides var. madrasens;l and G. glottoides var. a/ricanq. According to Mehra and Negi (1928) the shape of seminal vesicle is variable depending on the contents and condition at the time of preservation. According to Fotedar (1959) twisting of seminal vesicle brings about different shapes even among th~ members of the same species. Fotedar has recorded presence of metra-te~ in G. tigrinum although no mention of this structure was made by Mehra and Negi (1928), further he also agrees with MehTa and Negi in not assigning any value to slight variations in the position gonads.

• I
A careful study of the shape of excretory vesicle in various specios of Ganeo has revealed valuable information. Earlier workers havo' described it as 'U', 'V' and 'V' shaped but a close scrutiny of this stniQ" ture shows a remarkable resemblance. It is found in all cases to bs 'V' shaped, having either a very short (sometimes almost negIigil?le ) or slightly to fairly long median stem. In species having a broad posterio~' end, showing maximum contraction, the excretory vesicle is reporte~ as 'U' shape<;l. e.g. G. gastricus and G. Iinganensis. In specimens with moderate stage of extension the excretory vesicle is variously described 'U', 'V'and 'Y' Shaped with or without a median stem-'U' shaped in G. tigrinum, G. panjabensis, G. kumaonensis and -G. Some species of the genus Ganeo have been distingui~hed 0_ the basis of position and distribution of vitellaria in relation to gonads; ventral sucker and terminii of intestinal caeca. Views of Me.l1ra and Negi (1928) and Fotedar (1959) have been stated above for not giving importance to slight variations in the position of gonads. Similarly these .. ~pecies should not be differentiated on the basis of distribution of vitel·· laria in relation to gonads and the ventral sucker. It is observ~d that distribution of vitelline follicles in relation to body length provides a fairly stable character.
Text- fig. 1 A-C shows some of the variations occurring in G. tigrinum obtained from Rana cyanophlyctis from Jaisalmer and Jodhpur districts of Rajasthan in India. In two specimens (Text- fig. lA  Here rolative size of oral and ventral suckers, position of gonads in relation to the vontral sucker, laterality of testes and extension 0 f vitelline foellclcs in relation to body length have been utilized as stable chara~ters for differentiating species of the genus Ganeo.   Srivastava (1933) differentiated G. attenuatum from G .. tigrinum on the basis of attenuated shape of body, position, shape and size of luckers, shape of receptaculum seminis, shape of vesicula seminalis length of vitellaria, presence or metraterm and configuration of uterine coils. The omission of m~traterm in the description by Mehra and Negi (1928) should not be treated as a positive statement about its absence in G. tigrinflm. Further, Ganeo bu/onis, G. panjabensis and G. lingna-Remis which will be discussed below and are treated synonyms of G. ligrinum, give an indication about presence of metraterm. A few specimens in Dr. G. S. Thapar's collection, obtained from the gut of Rana cYQ1Jophlyctis ~t Lucknow and identified by this author as G.· tigrinum, show presence of metraterm. The receptaculum seminis is flask shaped both in G. tigrinum and G. attenuatum. As mentioned above, Mehra and Negi (1928) consider shape of vesicula seminalis as a variablo character. The vitelLaria occupy 1/5th instead of 1/4th of body 1ength as reported by Mehra & Negi in case of G. tigrillum. The extended condition of the specimen described by Srivastava appears ~o have resulted in the characteristic shap~ and configuration of uterine ccils, The ventra1 sucker is larger than the oral sucker, although not in "tho ratio of exactly 3: 2 asin the case orG. tigrinum. In view of the similaritios between tha two species it will be better to treat G. attenuatum as synonym of G. tigrinum. Li (1938) differentiated G. lingnanensis from G. tigrinum on the bas~ of presence of metraterm, shape of pars prostatica and position of an .. terior testis. The presence of metraterm in G. tigrinum has been mentioned while dealing with G. attenuatum. The remaining characters are· not sufficient to distinguish G. /ingnanensis from G. ligrinum. Fotedar (1959) has also inferred similarly. Dayal and Gupta (1953) distinguished Ganeo gobindia on the basis of diifer6nces in the structure of the excretory vesicle which is stated to be 'V' shap~d in G. gobindia and 'u' shaped (actually "Y' shaped) in G. tigrinum. The occurr~nce of G. gob india in Wal/ago attu (Bloch), a piscine host appears to be accidental since the hitherto known . . otb01' species are fro~ amphibian host with the' exception of another case when Simha (1958) has reported occurrence of G. tigrinum from tho intestine of Chamaeleon zeylanicus. The difference in the shape of excretory vesicle could ba ex.plained by the observations made above. Of the ten spJcimens studied by Da.yal and Gupta, only one. is mlture but its stunted gr()wth is apparent from the extremely small number of ova in the uterus. The stunted gr\lwth due to accidental nature of infection' is a common phenomenon. One spacimen (Z.S.1. registration number W 4165/1) collected from a toad, closely' resembles G. gobindia but differs from it in the shape of testes and vescicla seminalis. Therefore on the basis of other resemblances between the two species, G. gobinllia should be treated as a synonym of G. tigrinum.
Ganeo panjabensis Gupta, (N. K.) 1954 has 'U' shaped excretory vesicle with a median stem, vitelline follicles extending to caecal terminii and occupying the third quarter of body length, covering less than 1/4th of the body length and intestinal caeca extending behind the vitellaria. The 'U' shaped excretory vesicle with a median stem-basically 'V' shaped, has been described by Mehra and Negi in case of G. tigrinum. Singh (1954) has recorded ·the variation of caeca not extending behind vitellaria in case of G. kumaonensis. The vitelline follicle.s in G,. panjabensis show a range of distribution resembling that of G. tigrinum. Ganeo panjabensis so closely resembles G. tigrinum in having oral sucker smaller than the ventral, absence of pseudocirrus sac, position' of genital .,oning, arrangement of gonads and iheir position in relation to the ventral sucker and vitelline follicles commencing behind the ovary, that it will be desirable to treat' G. panjabensis as a synonym of G. ligrinum. Ganeo bufonis Fotedar (1959) is based on a single specim6Jl. It is distinguished from other species on the basis of both the vitellaria being situated on left sido of body. Fotedar (1959) has cited a numbel' of examples to justify creation of this species. Ciurea (1933) has reported atrophy of both the testes and vitellarium of the left side in case) of Metagonilnus yokogawa;. A similar case with vitellaria on one side has been reported by Kaw (1950) in case of Ganeo .sp. Dawes (1946) has stressod that such abnonnalities should not be treated as of any systematic value. Since G. bufonis resembles G. tigrinum in other characters, it is· considered as a synonym of the latter species.
2. Ganeo korkei Bhalerao, 19361936 J. Bhalerao (1936) has described vitelline follicles arranged in fivo groups on the left side and seven groups on the right side. Mehra and Nogi (1928) have stated in case of G. tigrinum that the veitellaria are not arranged in groups. No other species of this genus has viteIJine rolli .. icJes arranged in groups. It is felt that Bhalerao (1936) has possibly IIl8de an erroneous statement about grouped arrangement of vitelline follicles. Also the position of ventral sucker has not been shown by Bhalorao (1936) in the figure for G" korkei.

Ganeo komaonensis Pando, 1937
1937. GaIJfO klllnaonenJis Pande, Proc. Indian Acad. Sci., B, 6 : 109-120. 1950. Ganeo sp. Kaw, India" J. Helminthl, 1 : 91, 92. New synonyms 1959. Ganeo tigrillllnJ, Fotedar, J. Heltninth., 33 : 151-160. 1968. Ganeo gazipllre',sis Pandey and Chakrabarti,Sci. & Cult.,34 : 218,219. The distribution of vitelline follicles in G. kumaonens;s, ~ing about l/lrd in relation to body length, is most extensive. In Ganeo korkel they occupy slightly less than 1/3rd of body length. The excretory vosicle has a median stem in both the sp~cies but it is described as 'U' shaped in G. kUlnaonensis and 'V' shaped in G. korkei. These two species resemble each other so closely in the extension of intestinal caeca, arrangement of testes, position of ovary, the basic 'Y' shaped excretory vesicle and ventral sucker being larger than the oral sucker that slight difference in the distribution of vitelline follicles may not be sufficient to distinguish G. kUI1JaOllel1Sis and G. korkei. A study of the life history of these p:trasites may further elucidate this point. However, the two apecies are tentatively treated here distinct from each-other. Singh (1954) has reported 'occurrence of G. kumaonensis from Lucknow (U.P.). These fonns show certain interesting variations or caeca not extending behind vitelline follicles, size of testes and ovary, absence of spines from the metraterm. However, Singh's foim resembles G. korkei in the distribution of vitelJaria compared to body length. Fotedar (1959) has reported the occurrence of G. tigri~um from Bufo viridis in Kashmir. This"form resembles G. kumaonensis of Singh (1954). Fotedar's material show the extension of vitelline follicles to approximately 1/3 rd of body length whereas it is l/?th in G. tigrinum. These specimens support the similarity between G. korkei and G. kumao .. ' ensis as mentioned above. It is helpful to consider this point in viewof the occurrence of G. kumaolJensis in Kashmir reported by Kaw (1950), who has observed variations in the shape of body, size of testes, ovary, vitel1aria and excretory vescile. Pandey and Chakrabarti (1968) has been distinguished "by its authors from G. bufonis which has been shown above as a synonym of G. tigrinum. Simil(lJly G. gazipurensis is to be treated as a synonym of G. kumaonensi~ due to their similarjty in the extension of vitelline follicles, location and arrangement of gonads and length of intestinal caeca. Kaw (1950) had similarly treated Ganeo sp. in considering the location of vitellaria on one side only as an abberation.

Ganeo gazipurensis
In view of the synonymies of G. tigrinum indicated above, the emended diagnosis of this species is given below.
Emended diagnosis of Ganeo tigrinum Mehra & Negi : Body, 0.9-3. 7 mm. in length and O. 53-1 . 63 mm. in width, is highly contractile Cuticle spinose. Suckers nearly spherical or slightly transversely elongated. Oral sucker smaller than the ventral sucker. Prepharynx very small. Intestinal caeca extending 3j4th to 4j5th of body length in mature specimens and about 5/6th in immature specimens. They mayor may not extend behind the vitelline follicles. Sometimes caecum of one side may be slightly longer than the other. Gonads very closely situatod; their position greatly variab1e in relation to one another. Testes obliquely situated and ovary is post-testicular. Vesicula seminaIis variously coiled. Uterus intercaecal and post acetabular, metratenn present. Vitellaria occupying middle portion of body, covering 1/5th to 1/4th body length. ExcretorY'vesicle 'Y' shaped, capable of changing with contraction or extension of body. Host and Geographical distribution of the genus Ganeo.
Almost aU the species are parasites 0 f frogs (Rana: Ranida~). In a few cases they have been reported from toads (Bufo : Bufonidae). Ganeo tigrinum has been recorded once from a piscinL host, Wallago attu and on another occasion from a reptilian host, Chamaeleon zeylanicus.
Geographically the genus Ganeo is known practically from the Oriental Region (Text- fig. 2) with the exception of G. africana and G. glotloides occuring in Africa (Ehtiopian Region). The report of G. glottoides from Athieme (Dahomey) on the south western coast of Africa is interesting as this species is known from Tamil Nadu (southem India) and Sri Lanka. Ganeo tigrinum is the most wideiy distributedspeci. occurring from eastern to the western limits of the Oriental Region.
Certain descrepancies in the description of, G. korke! Bhalcrao., 1926 have been pointed out. Probabi1ity of synonym} between G. korkei and G. kumaonensil has been hinted.
Host and Geographical distribution of the genus Ganeo have been studied. ACKNOWLEDGEMENT The author is than~ful to the Director, Zoological Survey of India, Calcutta for the facilities and suggestions during this work.