8 RES. BULL. MEGURO PARASIT. MUS. No.7, p. 8- 11 , 1973

STATUS OF THE GENUS GLOSS/METRA MEHRA, 1937 (FAMILY-PLAGIORCHIDAE (L(fHE, 1901) WARD, 1917) IN

STYPHLOTREMATINAE BAER, 1924, ASTIOTREMATINAE BAER, 1924 AND STYPHLODORINAE DOLLFUS, 1937 COMPLEX

A. N. GUPTA and P. N. SHARMA

(Department of Zoology, University of Udaipur, Udaipur, Rajasthan, India)

ABSTRACT: YAMAGUTl and SKRJABIN differ vitally regarding the assignment of Glossimetra MEHRA, 1937 along with other common and uncommon genera under the subfamilies Astiotrematinae BAER, 1924 ; Styphlotrematinae BAER, 1924 and Styphlodorinae DOLLF US, 1937. Recognition of Astiotrematinae by YAMAGUTl and not by SKRJABIN, recognition of Styphlotrematinae by SKRJABIN and not by YAMAGUTI on one hand and recognition of Styphodorinae by both lends complication in the taxonomy. Exclusion of Neomicroderma PARK, 1940 and Parallopharynx CABALLERO, 1946 from Astiotrematinae along with a suggestion that Astiotrematinae, Styphlodorinae and Plagiorchinae of the family Plagiorchidae LUHE, 1901 do not differ much in their diagnostic characters.

This is the second paper of the current series on this genus. The first being "Re­view of the genus Glossimetra MEHRA, 1937 and proposed synonymy of G. narmadi DWIVEDI, 1967 and G. tamiensis DWIVEDI, 1967 with G. orientalis MEHRA, 1937" (1970). In the third paper an attempt has been made to discuss the validity of different genera assigned under these subfamilies.

The genus Glossimetra was erected by MEHRA(1937). YAMAGUTI in his monumental memoir Systema Helminthum (1958) inclu­des this genus in Astiotrematinae BAER, 1924. He along with Glossimetra includes the following genera, these being, Astio­trema Looss, 1900; Allopharynx STROMA, 1928; Glossidiella TRA v ASSOS, 1927; Micro­derma MEHRA, 1931 ; Neomicroderma PARK, 1940 ; Parallopharynx CABALLERO, 1946 and Spinometra MEHRA, 1931. However, SKRJ­ABIN instead of agreeing with Y AMAGUTI in assigning the genus Glossimetra in Asti­otrematinae differs in recogmzlllg the validity of this subfamily. He rather as­signs it under a separate subfamily Sty­phlotrematinae BAER,1924 of family Plagior­chidae recognized by SKRJABIN and others (1964) (see Key to trematodes of Animals and Man, Translated by R. W. DOOL Y) not recognized by YAMAGUTI (1958). SKRJABIN includes Glossimetra MEHRA, 1937 along Received for publication Dec. 15, 1970

with genera Pachypsolus Looss, 1901; Sty­phlotrema ODHNER, 1911 ; Styphlodora Looss, 1899; Glossidium Looss, 1899. Thus SKRJ­ABIN includes the three genera of Astio­trematinae recognized by YAMAG UTI only under this subfamily-viz., Glossimetra, Spi­nometra and Glossidiella. Naturally, this poses a question whether Astiotrematinae BAER, 1924 and Styphlotrematinae BAER, 1924 are synonyms though either of the two authors recognized only one of the two . Since both these subfamilies were created by BAER in 1924 they must have been done on distinction from one another. The dif­ferences between the two subfamilies main­ly are in the shape of the seminal vesicle and pars prostatica. Neither SKRJABIN nor Y AMAG UTI ever mentioned that one is synonymous to the other. The inclusion of uncommon genera in the list of the genera included under these two subfami­lies, makes it further complicated. This reflects whether these uncommon genera are valid and recognized by both of them, if so reasons for these being assigned under separate subfamilies . Y AMAGUTI recognizes all these four genera viz., Pachypsolus Looss, 1901 ; Styphlotrema ODHNER, 1911; Styphlodora Looss, 1899 and Glossidium Looss, 1899. But he assigns all except Pachypsolus under another subfamily Sty-

GUPT A, A. N. & SHARMA, P. N. 9

phlodorinae DOLLFUS, 1937 belonging to the family Plagiorchidae. Pachypsolus is assign­ed under a new family Pachypsolidae Y AMAGUTI, 1958. This family is not rec­ognized by SKRJABIN and he has made the problem all the more complicated by in­cluding Glossidiella TRAvAssos, 1927 in two distinct subfamilies viz., Styphlotrematinae BAER, 1924 and Styphlodorinae DOLLFUS, 1937. SKRJABIN keeps the genus Allopharynx in Styphlodorinae while the two genera assigned by YAMAGUTI under Astiotrema­tinae viz., Parallopharynx CABALLERO, 1940 and Neomicroderma PARK, 1940 are not recognized by SKRJABIN. SKRJABIN further complicates the issue by assigning the genus Astiotrema under two subfamilies namely Lepodermatinae Looss, 1899 and Plagiorchinae PRATT, 1902. The assign­ment of the same genus under two distinct and recognized subfamilies belonging to Plagiorchidae naturally takes ones to a fix. Lopodermatinae Looss, 1899, however, is not recognized by YAMAGUTI.

The genus Microderma MEHRA, 1931 assigned by Y AMAGUTI under Astiotrema­tinae is instead kept by SKRJABIN under Lepodermatinae Looss, 1899 and Plagior­chinae PRATT, 1902. The subfamily Lepo­dermatinae apart from Astiotrema includes Haplometra Looss, 1899; Haplometrana LUCKER, 1931; Microderma MEHRA, 1931; Lepoderma Looss, 1899; Neolepoderma PARK, 1940 and Glypthelmins STAFF., 1905 according to SKRJBIN. Here again comes the same question - inclusion of the same genera under two distinct subfamilies be­longing to Plagiorchidae LUHE,1902. Besides Astiotrema and Microderma the genera Haplometra, Haplometrana and Glypthelmins are also included in two separate subfami­lies Lepodermatinae Looss, 1899 and Plagi­orchinae PRATT, 1902.

The status of the genus Glossimetra is further highlightened because of its another placing when one looks into the different genera assigned under the subfamily Sty­phlodorinae DOLLFUS, 1937. SKRJABIN as­signs this genus Glossimetra MEHRA, 1937 in this subfamily also and along with it

are included Spinometra , Allopharynx and Glossidiella too. So except for Astiotrema all other genera included under Astiotrem­atinae by Y AMAGUTI figure under this subfamily Styphlodorinae according to SKRJABIN who does not recognize Paral­lopharynx and Neomicroderma. Thus only Microderma is not included under Styphlo­dorinae by SKRJABIN. This instead has got its placement under two subfamilies viz., Lepodermatinae Looss, 1899 and Plagi­orchinae PRATT, 1902 as discussed earlier.

It appears there could be a little bit unanimity of opinion between the taxonomic position of these genera if the two sub­families viz., Astiotrematinae and Styphlo­dorinae could be synonymized. But SKRJ­ABIN recognizes Styphlodorinae and not Astiotrematinae while Y AMAGUTI recognizes both as distinct. The practical difficulty about the placement of the same genera under two distinct subfamilies by SKRJABIN remains inexplicable. A comparison of the genera included by SKRJABIN under sub­families Styplotrematinae and Styphlodo­r inae reflects this aspect. Except Glos­sidioids Y AMAGUTI, 1958 and Allopharynx STROMA, 1928 which are kept in Styphlodo­rinae and Pachypsolus Looss, 1901 and Sty­phlotrema ODHNER, 1911 which are included in Styphlotrematinae. There are common genera included under the two subfamilies viz., Styphlotrematinae and Styphlodorinae. A detailed study of the above mentioned genera and the species included them might help solve this tangle and in that case both may be attempted to be declared synony­mous. A next step would then be to com­pare Styphlodorinae of SKRJABIN concept and Astiotrematinae of Y AMAGUTI concept, and because of near closeness in the inclu­sion of most of the similar genera by the two wizzards of trematode taxonomy, at­tempts would be made to overhaul and then suppress Astiotrematinae and uphold Styphlodorinae. But this venture faces one more hurdle as Y AMAGUTI also recognizes Styphlodorinae. In Y AMAGUTI's concept of Styphlodorinae only such genera viz., Sty­phlodora; Glossidioides and Glossidium which

10 RES. BULL. MEGURO PARASIT. MUS. No.7, 1973

are slso included in Styphlodorinae of SKRJ­RBIN concept are common among the list containing 14 genera which have been in­cluded by YAMAGUTI in subfamily Styphlo­dorinae.

The present authors are, however, also of the view that inclusion of the genera Neomicroderma and Parallopharynx by YAM­AGUTI under the subfamily Astiotrema­tinae is not justified in view of the tandem position of their testes apart from few other characters for example postequatorial position of the ovary in case of Paral­lopharynx.

On looking into the three subfamilies of the family Plagiorchidae namely Astiotrem­atinae, Styphlodorinae and Plagiorchinae, it is clear that there are not much points significant enough on which the distinctive characters of the three subfamilies could be maintained. When these three sub­families viz., Astiotrematinae, Styphlodo­rinae and Plagiorchinae are compared from points of view of their diagnostic chara­cters appears that except in the location of ventral sucker, testes and ovary from the anterior end, the three subfamilies appear very similar in their diagnostic characters. The dissimilarities appear either superficial, artificially created or not worth of a sub­family rank. All the three resemble in shape of body, spinose or unspinose chara­cters of their body wall, in having oesophagus, generally small . Oral sucker small or moderately developed, caeca ex­tending to posterior end mostly. Testes mostly oblique to diagonal vitelline follicles extending laterally in hind body. Whatever little difference do these have can hardly form characters of subfamily distinction.

The characters of ventral sucker regard­ing its location from the anterior end, position of genital opening in relation to ventral sucker; position of testes from anterior end, position of ovary from ventral sucker are characters of phylogenetic signi­ficance. The present authors, however, feel that there are clear indications for the disposition of testes to be oblique, diagonol then symmetrical being situated in poste-

rior half of middle third of body, mid region or posterior half of body or poste­rior half of body or posterior half to middle third of body. The testes being separated by uterine coils.

Further there is a tendency for cirrus sac to be elongated and then extend as far as beyond ventral sucker or to be nearer ovary.

The ovary progressively shows a ten­dency to move away from the anterior testis and come to be nearer ventral sucker. In Astiotrematinae, the ovary is widely separated from ventral sucker and anterior testis . In Styphlodorinae it is nearer ven­tral sucker and anterior testis while in Plagiorchinae it is posterior or posterolat­eral to acetabulum.

Similarly the position of the genital opening shows a drift from the preace­tabular position to a position anterior to acetabulum then to be immediately pre­acetabular as one passes from Astiotrema­tinae to Styphlodorinae and Plagiorchinae.

ACKNOWLEDGEMENT

The authors feel grateful to Prof. M. YOKOGAWA for critical analysis of the manuscript and also owe to C. S. 1. R., India.

REFERENCES

1) CABALLERO, Y. C. E. (1946) : Estudios hel­mintologicos de la region Onchoceracosa de Mexico Y de la republica de Guatemala. Trem­atoda II Presencia de Pm·agonimus en reser­vorios naturales Y descripcion de un nuevo genero. An. Inst. Bioi., 17 (1-2), 137-165.

2) DWIVEDI, M. P. (1967): Description of two new species of the genus Glossimetra MEHRA, 1937 (Plagiorchidae : Trematoda.) Proc. Indian Acad. Sci. Sec. B, 65 (5), 200-209.

3) Looss, A. (1899): Weitere Beitrage zur ken­ntnis der trematoden fauna Aegyptens zugleier versuch einer naturlichen Gliederung des genus Distomum RETZIUS. Zool. Jahrb. Syst., 12, 521-784.

4) Looss, A. (1900): Nachtragliche Berner Ku­ngen zu den Namen der von mir vorgeschla­genen distomidengattungen. Zool. Anz., 23, 601-608.

5) LUCKER, J. T. (1931) : A new genus and new species of trematode worms of the family Plagiorchidae. Proc. U. S. Nat. Mus. , 79 (19),

GUPTA, A. N. & SHARMA, P. N . 11

1- 18. 6) MEHRA , H. R. (1931) : On a new trematode

Microder ma elinguis. Parasit. , 23 , 191-195. 7) MEHRA, H. R. (1931) : A new genus (Spino·

metra ) of the family Lepodermatidae ODHNER (Trematoda) from a tortoise, with a systematic discussion a nd classification of the famil y. Parasit., 23, 157- 178.

8) MEHRA, H. R. (1928): On a new genus Spinomet1'a belonging to the family Lepoder­ma tidae from Kachuga dhongoka .Proc. 15 Ind. Sci . Congr. P. 200.

9) MEHRA , H. R. (1937): Certain new and already known distomes of the family Lepoder· matidae ODH NER (Trematoda), with a discus­sion on the classification of the fami ly. Zeitschr. Parasit . , 9 (4), 429-469.

10) ODHNER , T . (1911): Zum naturlichen System der digenen Trematoden. Zool. Anz. , 37 (8-9), 181-191.

11) PARK, J. T . (1940) : Trematode parasites of reptilia from T yosen 1. Three digenetic trem-

atodes, E ncyclometra koreana sp. nov., Neo­mic1'oderma elongata gen. nov., sp. nov. (Plagi­orchidae) and Proalarioides kobayashii sp. nov. (Strigeidae). K eijo,]. M ed. , 10 (3), 113-123.

12) PRATT, H. S. (1902) : Synonpsis of North America n Invertebrates XII. The trematodes part II. The Aspidocotylea and the malaco­cotylea, or digenetic forms. Illustrations in Part III. A m. Nat ., 36, 887-910, 953-979.

13) SHARMA, P . N. a nd GUFTA, A. N. (1970): Review of genus Clossimetra MEHRA, 1937 and proposed synonymy of C. tamiensis DWI VEDI , 1967 and C. narmadi DWI VEDI , 1967 with C. orientalis MEHRA, 1937. Res. B ull. M eg uro Parasi t. M us., N o.5, 6-13.

14) SKRJABIN , K. I. (1964) : Keys to the trema-todes of animals and man. University of Illinois Press, Urbana.

15) YAMAGUTl , S. (1958): Systema Helminthum Vol. I. The trematodes of vertebrates. Int. Sci. Pub. Inc. , New York.