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THREE NEW FRONDS FROM THE GLOSSOPTERIS FLORA OF

P. K. MAITHY Birbal Sahni Institute of Palaeobotany, Lucknow-226007

ABSTRACT of dates, Damudopteris becomes synonym A new of Neomariopteris and a new to Neomariopteris, because the former form species of Dichotomopteris is recorded. In addition has been published one month later. to this a new Santhalea is instituted.

INTRODUCTION Neomariopteris khanU sp. novo

Diagnosis - Fronds large, at least tri• the from the Lower knowledge on the morphology of pinnate; catadromic, rachis winged, secon• OURof India has been advanced consider• dary rachis broad, emerge alternately at an ably from the recent work of Maithy (1974a, angle of ± 60°; pinnae lanceolate; attached 1974b, 1975), Pant and Misra (1976) and alternate, sub-opposite or opposite from Pant and Khare (1974). Recently Maithy secondary rachis; lateral pinnules ovate, has revised the Lower ferns from 1'0 cm long and 0'4 mm broad at base, i.e. India. On the basis of his revision, he has the length and breadth ratio of the pinnules instituted two new genera Neomariopteris is 2·5: I, lateral pinnules alternately and Dichotomopteris and an unrecorded form arranged, standing at right angles to rachis, Dizeugotheca. Pant and Khare (1974) and decurrent, attached by broad bases, lateral Pant and Misra (1976) have reported two fusion of two pinnules margin is ± 1/4 length new genera Damudopteris and Asansolia from of the pinnules from the base; apex acute; the Raniganj Coalfield. margin entire; both the margins show out• The present paper deals with three new ward curvature; terminal pinnules smaller fern fronds collected recently from than lateral pinnules, triangular in shape. Handappa, Dhenakal, Orissa and the village apex pointed; venation sphenopteroid, Tatti, on the north bank of Bansloi River, median vein distinct, emerge at 45° from Santhal Pargana, Bihar. The materials are the point where the lower margin of pin• preserved in the form of impressions. nules join the pinnae rachis, course straight, Sincere thanks are due to Dr K. R. median vein gives fine lateral nervules Surange and Dr Shaila Chandra for passing which dichotomises once before reaching on the Handappa collection for investiga• the margin, 10-12 nervules recorded in tion. one pinnule. Holotype-No. 35237, Birbal Sahni Insti• tute of Palaeobotany, Lucknow. Neomariopteris Maithy, 1974 Locality - Handappa, Orissa. Horizon - Kamthi Formation (Upper N eomariapteris waS proposed by Maithy ). (1974) for the Indian Lower Gondwana Description - A large incomplete frond fern fronds with sphenopteroid venation, has been figured in PI. I, fig. 1. The decurrent pinm,les and winged rachis. Sub• median rachis is thick, 7 mm at the in• sequently in 1975, Maithy recorded the complete base and 4 mm at the incomplete fertile pinnules and emended the diagnosis. apex. Surface of the rachis shows fine Pant and Khare (1974) published a new striations. The rachis is narrowly winged. genus Damudopteris with same morphologi• Secondary rachises are arranged alternately cal characters of N eomariopteris. Even both on both the sides of main rachis at a dis• the authors have chosen the same specimen, tance of 0·8 to 1·5 cm from apex to base. i.e. Sphenopteris poZymorpha IFeistmantel The distance in between alternating pair (1880), as the genotype for their proposed of secondary rachises decrease as we mea• genus. Therefore, on the basis of priority sure from base to apex of the frond. The 96 MAITHY _ THREE FERN FRONDS FROM GLOSSOPTERIS FLORA OF INDIA 97

TEXT-FIG. 1 - Neornariopteris khanii sp. nov., a pinnae enlarged to show venation of pinnules x 4.

secondary rachises are attached at 60° on (1974)has obovate pinnule and N. talchirensis the main rachis. The basal most secondary Maithy (1974) is a frail species. rachis is 18 em long and 14 pinna are Derivation 0/ Name - The species is named arranged on it. Secondary rachis is dis• after late Mr A. M. Khan of Geological tinctly winged. Pinnae are attached, alter• Survey of India, Calcutta who first dis• nate to one other at the basal portion of covered this locality. secondary rachis, sub-opposite in the median portion and opposite at the terminal portion or near it. Pinnae are attached at + 90° Santhalea gen. novo to secondary rachis, due to this a fairly Generic Diagnosis - Fronds large, impari• good distance (5'5-6'5 em) is observed in pinnate, tripinnate; rachis winged; pinnules between succeeding secondary rachises. decurrent, attached to rachis by broad base, Pinnae lanceolate in shape measuring 2-3·5 venation pecopteroid; single midvein per• em in length. Lateral pinnules 5 to 8 on either side of pinnae rachis. Later pinnules sistent up to apex, lateral veins towards apical part, simple, whereas in basal part are alternately arranged and attached divides into two, three or four veinlets; ± right angles to the rachis. The basal when three, the distal one divides into two margin of pinnules are longer drawn than and the proximal remains undivided, and the apical end of margin. As a result of when four the proximal remains undevided this th.e pinnules apex is oblique in position and in the distal one the proximal one to pinnae rachis. A midvein is persistent divides into two veinlets and distal one up to 1/3 from base which diffuses into remains unforked. R.eproductive structures secondary veins by dich.otomy. Margin unknown. of the pinnules entire. Terminal pinnule is triangular and smaller than the lateral pinnules. Fertile organs are not known. Genotype - Santhalea bansloiensis sp. novo Comparison - The frond is characterised by its large size and robust look, hence it Comparison - The identification of ferns differs from all the known species of from the Glossopteris flora are based upon Neomariopteris. Neomariopteris polymorpha the morphological characters and the pat• (Feistm.) Maith'y, 1974 compares due to tern of venation. Previous studies have strong winged rachis, but differs in the demonstrated that the ferns from the shape of pinnules, apex and right angle Lower Gondwanas, viz., Neomariopteris, alignment of pinnules. Neomariopteris Dichotomopteris and Dizeugotheca show a hughesii (Feistm.) Maithy, 1974 compares uniform type of venation in all pinnules. in the oblique alignment of pinnules to Similar uniformity in the pattern of vena• pinnae rachis, but differs in the presence of tion is also known in the modern ferns, extremely narrow winged rachis. Moreover, viz., Pteris, Goniophlebium, Gymnogramma in N. hughesii the pinnule margins are and Microlepia. There are other modern serrate. Other species, N. lobi/olia Maithy ferns where the pattern of venation varies 98 THE PALAEOBOTANIST

in different pinnules. The veins are simple Diagnosis - Sterile fronds imparipinnate, in nature in the apical pinnules, while they tripinnate frond, rachis broadly winged, 5 are dichotomous once or more than once in mm broad with two distinct ridges; pinnae basal pinnules. Such type of venation is lanceolate, arranged alternately, at an angle seen in Diplazium, Lindsaea, Alsophila and of 450; pinnules attached to pinnae rachis Cyathea. The present frond Santhalea be• at wide angle, 80°-90°, contiguous to each longs to the second type and it shows other by base, cleft between pinnules deep, variation in the pattern of venation in oblong in shape with obtuse apex, midvein different pinnules from apex to base. But distinct and persistent upto apex, lateral this too is characteristic in the genus as veins arranged alternately; simple or divides detailed below. into 2, 3 or 4 veinlets; when 3, the proximal The frond of this genus is identified by one remains undivided and the distal one winged rachis and characteristic venation divides into 2; and when 4, the proximal pattern, which is from simple to dichoto• remains undivided, while the distal divided mous into 2, 3 or 4 veinlets. The dichotomy into two and lastly the vein of proximal. of veins is also characteristic. The present side divides into two and the distal one frond shows its closest resemblance to remains unforked. Pecopteris Brongniart, but it differs from Holotype - No. 35238, Birbal Sahni Insti~ Santhalea gen. novo in the absence of basal tute of Palaeobotany, Lucknow. contiguity of the pinnules and winged Locality - On the north bank of Bansloi rachis. Alethopteris Sternberg agrees due River near the village Tatti, Pachwara to basal contiguity of pinnules, but differs Coalfield, Santhal Pargana, Bihar. in the presence of veins from pinnae rachis Horizon -? Raniganj. in the basal region of pinnules. Dizeugo• Description - The identification of frond theca Archangelsky & Sota (1960) compares is based upon number of incomplete speci• morphologically but differs due to presence menS collected from the above mentioned of only simple veins. Dichotomopteris Maithy locality and the specimens described by (1974b) differs in the venation pattern. Maheshwari and Prakash (1965). The speci• In Dichotomopteris the mid vein is evane• men figured here in PI. 2, fig. 3 is a portion scent whereas in Santhalea it is persistent of bipinnate frond. The primary rachis is upto apex. Moreover the lateral veins in distinctly winged with two distinct vertical Dichotomopteris is always divided into 2 or ridges in the middle region. Veins in the 3 veinlets, whereas in Santhalea the veins pinnules present at the apical part of pinnae are simple and divided into 2, 3 or 4 vein• are simple and rarely dichotomous, whereas lets. Further, in Santhalea the rachis is the veins in the pinnules present in the basal winged whereas in Dichotomopteris the rachis part of fronds are either divided into two is non-winged. Lobatopteris Wagner (1958a) or three or four veinlets. All the variations and Polymorphopteris Wagner (1958b) com• of the venation patterns are seen in the pares somewhat morphologically, but dif• specimen figured by Maheshwari and fers in having the basal veins forked into Prakash (1965, pI. 1, fig. 9). In this speci• two. In Santhalea the veins are forked. men, the pinnules towards the apical end Derivation of Name - After the district of frond show simple veins or veins divided Santhal Pargana, Bihar. into two veinlets, whereas the pinnules in the basal portion of frond show that the veins are either divided into two, three or Santhalea bansloiensis sp. novo four veinlets (see Pl. 2, figs. 3, 4, 5; Text• figs. 2 A-C). Pl. 2, figs. 3-6; Text-figs. 2A-C Comparison 0- Discussion - The present Synonymy: form shows characteristic arrangement of venation in the entire frond. A careful 1965-Pecopteris sp., Maheshwari & Prakash; examination of the specimens described by pI. 1, fig. 1; text-fig. 4. Maheshwari and Prakash (1965) under 1965 - Alethopteris sp. A, Maheshwari & Pecopteris sp., Alethopteris A and Aletho· Prakash; pI. 1, fig. 8; text-fig. 4. pteris B show that they are different por• 1965 - Alethopteris sp. B, Maheshwari & tions of the same frond. The specimen Prakash; pI. 1, fig. 9; text-fig. 5. described Alethopteris A represents the MAITHY - THREE FERN FRONDS FROM GLOSSOPTERIS FLORA OF INDIA 99

A

.'. ,.'

c

TEXT-FIG. 2 -;,A-C, Santhalea bansloiensis gen. et sp. nov.; A. a pinnule enlarged to show simple an.d dIchotomous veins X 4; B. a pinnule enlarged to show simple and dichotomous veins into 2 or. 3 vem endmgs X 4; C. a pinnule enlarged to show dichotomous veins dividing into 2, 3 or 4 vem endings.

apical portion of frond, Pecopteris sp. re• Dichotomopteris Maltby, 1974 presents the middle portion and Aletho• pteris B represents the basal portion. Dichotomopteris ovata sp. novo Hence, all of them have been transferred PI. 2, fig. 7; Text-fig. 3 here under one species. Lacey and Huard-Moine (1966) reported Synonymy: Cladophlebis ct. nibbensis from Wankie, R.hodesia. This specimen appears alike to 1960 - M erianopteris sp. Archangelsky & the present form. Sota, p. 118; pI. 4, fig. 19; text-figs. 74-75. 100 TH,E PALAEO BOTANIST

L(Jcality - Near the Tatti Village on the north bank of Bansloi River, Pachwara Coalfield, Santhal Pargana, Bihar. Horizon - ?Raniganj. Comparison - Till now only three species of Dichotomopteris, viz., D. major Maithy (1974b, 1975), D. lindleyii Maithy (1974b, 1975) and D. falcata Maithy (1975) are known from the Lower Gondwanas of India. Morphologically the present form agrees to the above mentioned species but differs due to characteristic vena1ion, i.e. the veins are flexuosus and the lateral veins show outward radial curvatuH' parallel to pinnule margin. Moreover, D. lindleyii and D. falcata differs in the shape of pinllules. D. major compares in shape but differs in the course of veins and also the alignment of pinnules on the pinnae rachis. TEXT-FIG. 3 - Dichotomopteris ovata, pinnules Archangelsky and Sota (1960) described enlarged to show venation x 4. Merianopteris sp. (figs. 74-75; pI. 4, fig. 19) from the Permian of Patagonia, which agrees morphologically to the present form Diagnosis - Fronds bipinnate, rachis non• and are alike. winged; pinnae alternate, perpendicular to rachis; lateral pinnules alternate, attached obliquely, ± 50° from rachis, oblong in GENERAL REMARKS outline, 8-12 mm long and 6-9 mm broad, apex obtuse, base broad and decurrent; Earlier the Indian Lower Gondwana fern lateral fusion ± 1/2 length from the base of genera have been classed under Sphdno• pinnules; venation catadromic, single dis• pteris, Pecopteris, Alethopteris and Meriano• tinct midvein arises just at the line of pteris. Recent studies have rightly demons• pinnule base, which passes to pinnule with trated that the Lower Gondwana ferns, strong radial curvature; mid vein persistent though superficially alike to northern 1/2 length of the pinnule from base and then forms, but differs consider• dissolving into secondary veins by repeated ably. This has also been supported by dichotomy. Lateral veins commonly two the record of their fertile fronds. A com• pairs, arranged alternately, dichotomise mon feature noticed in all the Indian forms always into two, course of veins characteri• that the pinnules near the bases are laterally stic, they show strong curvature parallel to contiguous, though they differ in their pinnule margins. The first lateral vein of venation pattern. Therefore, the generic the proximal side arises just at the point of identification of ferns are based on the emergence of midvein from pinnae rachis, pattern of venation. The specific identi• its direction is more or less parallel to fications are based on the morphology of pinnule margin; while the lateral vein of pinnules (shape and apex). This approach distal side emerges distinctly away from of identification appears to be satisfactory, the first basal vein, subsequent veins are because, often only the sterile parts of closely arranged; course of veins ftexuosus. fronds are found in Palaeozoic strata and Holotype - No. 35239, Birbal Sahni Insti• these are the specimens with which the tute of Palaeobotany, Lucknow. palaeobotanical stratigrapher works.

REFERENCES

ARCHANGELSKY,S. & SOTA,E. D. L. (1960). Contri• FEISTMANTEL, O. (1880). The fossil flora of butional conocimients de las Filices Permicas Gondwana system. II. The) flora of Damuda de Patagonia Extraandina. Acta geol. liUoana Panchet Division. Mem. geol. surv. India 3: 85-126. Palaeont. indica. Ser. 12. 3 (2): 1-77. THE PALAEOBOTANIST, VOL. 24 MAITHY - PLATE 1 MAITRY - PLATE 2 THE PALAEOBOTA:-!IST, VOL. 24 MAITHY - THREE FERN FRONDS FROM GLOSSOPTERIS FLORA OF INDIA 101

LACEY, W. S. & HUARD-MOINE,D. (1966). Karroo PANT, D. D. & KHARE, P. (1974). Darnudopteris floras of Rhodesia and Malwai. Part 2. The gen. novo a new genus of ferns from the Lower Glossopteris flora in the Wankie District of Gondwanas of the Raniganj Coalfield, India. Southern Rhodesia. Symposium on Floristic Proc. R. Soc. London. 186: 121-125. and Stratigraphy of Gondwanaland. Birbal Sahni PANT, D.D. & MISRA, L. (1976). Compressions of Institute of Palaeobotany, Lucknow: 13-25. a new type of Pteridophyll Asansolia gen. novo MAITHY, P. K. (1974a). A revision of the Lower from the Lower Gondwana of the Haniganj Gondwana Sphenopteris from India. Palaeo• Coalfiled, India. Palaeontographica. 155 (5-6): botanist. 21 (1): 70-80. 129-139. IDEM (1974b). Dichotomopteris, a new type of WAGNER, R. H. (1958a). Some Stephanian Peco• fern frond from the Lower Gondwana of India. pleris from N.W. Spain - Meded. geol. Sticht. Ibid. 21 (3): 365-367. (N.S.). 12: 5-23. IDEM (1975). Some contribution to the knowledge IDEM (1958b). Pecopteris psuedobucklandi Andrae of Indian Lower Gondwana Ferns. Ibid. 22 (1): and its general affinities. Ibid. 12: 25-30. 29-38.

EXPLANATION OF PLATES

PLATE 1 4. Pinnules enlarged to show simple and single dichotomous veins. X 4. B.S.I.P. specimen no. 1. Neornariopteris hhanii sp. novo X 2/3. B.S.I.P. 32851. specimen n0. 35237. 5. Two pinnules enlarged to show their lateral 2. A pinnae of the above specimen enlarged to contiguity at base and persistent midvein. X 4. show venation. X 4. Lateral veins simple or dichotomous into 2 or 3 veinlets. B.S.I.P. specimen no. 35238. 6. A pinnule enlarged to show dichotomy of lateral veins into 2, 3 or 4 veinlets. X 4. B.S.I.P. PLATE 2 specimen no. 32853. Santhalea bansloiensis gen. et sp. novo Dichotornopteris ovata sp. novo

3. A specimen showing the attachment of pinnae 7. A pinnae enlarged to show venation. X 4. to winged rachis. X 1. B.S.I.P. specimen no. 35238 B.S.I.P. specimen no. 35239.