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A NEW MICROSPORANGIAtE FRuCTIFICAtION FROM THE TRIASSIC OF NIDPUR, INDIA

SHYAM C. SRIVASTAVA Birbal Salmi Institute of Palaeobotany, Lucknow

ABSTRACT axis elongated, rectangular; sporophyll A carbonized -bearing fructification under cuticle amphistomatic, stomata longitudi• Bosea indica gen. et sp. novo has been described nally or obliquely orientated, subsidiary here from Nidpur beds. It consists of an axis cells papillate, 5 or 6 in number, papillae with rnicrosporophylls arranged in opposite or overhanging stomatal pit, sporangial wall sub-opposite order. The rnicrosporophyll is flat• tened and elongated, along the margin of which membranous with rectangular or rhom• sporangia are borne pendant on its under surface. boidal cells, striate, non-saccate, Each sporangium contains Weylandites-type of circular or oval with transverse striations on spore. proximal face and distally vertically striated. Bosea indica, in its sporophyll cuticle, resembles Type species - Bosea indica gen. et sp. Lepidopteris indica Bose & Srivastava. In its novo spore-type, it is distinct from all the so far known pteridosperrnic fructifications. Bosea indica gen. et sp. novo INTRODUCTION PI. 1, Figs. 1-12, Text-figs. 1A-F

Diagnosis - Male fructification 3.6 em. fructifications have been recorded RECENTLY, some male and female long, consisting of axis with elongate, flat, from the Triassic sediments of opposite or sub-opposite microsporophylls Nidpur, namely, Nidistrobus, Nidia, Sat• showing distinct parallel veins, sporangia sangia and Pteruchus (See, Bose and all along the margin on the under surface Srivastava, 1973a & b; Srivastava and of microsporophyll, sporangia near the Maheshwari, 1973; Pant and Basu, 1973 basiscopic side 1.5-2 mm. long and 1 mm. and Srivastava, 1974). Associated with broad, sporangia usually conical or oblong, these, a new microsporophyll, preserved sometimes more or less lanceolate with in the form of compression has been orbicular, blunt or pointed apex, sporangia collected by Dr. M. N. Bose to whom I am perhaps partially fused in basal portions; grateful for entrusting me the specimen sporophyll cuticle 2.5 [.I, thick, epidermal for description. Though the specimen is cells rectangular or polygonal, lateral- and imperfect from base and apex and also end-walls straight, at places undulated, none of the microsporophylls is complete papillate, papillae oval or round; stomata yet it provides sufficient data not to refer lesser on one surface than the other, irreg• it to any of the existing form genera. In ularly distributed, stomatal apparatus more view of its importance as the only specimen or less circular with papillae overhanging from India and in having characteristic stomatal pit, guard cells sunken, thickly spore contents which were described in cutinized all round, aperture slit-like; spor• dispersed condition as Weylandites by angium wall cells polygonal in basal region; Bharadwaj and Srivastava (1969), it is sporangia unilocular, apical dehiscence; being designated here under a new generic spores 25.5-60 [.I, X 12.5-35.5 [.1" distally ver• name Bosea. tical striations present on each side of biconvex sulcus, on proximal face exine Bosea gen. nov microverrucose with numerous horiwntal striations, striations on both the faces con• Diagnosis - Male fructification, micro• tinuous with each other, sometimes irre• sporophylls attached on axis at an acute gularly distributed curving in oblique angle, opposite or sub-opposite; micro• direction. sporophylls narrow, flattened, elongated and Holotype - No. 35154 of the Birbal Sahni sporangia pendant along margin; cells of Institute of Palaeobotany, Lucknow. 19 20 'IRE P ALAEOBOT ANtST

TEXT-FIG. 1 - Bosea indica gen. et sp. novo A, a branched fructification, showing arrangement of microsporophylls and longitudinally ribbed surface, of axis. Rolotype No. 35154. x 3. B, showing epidermal cells of axis in between minor folds. Slide No. 35154-1. x 250. C, sporophyll cuticle showing stomata 011 both the surfaces. Slide No. 35154-6. X 100. D, cells along the fringe of head. Slide No. 35154-1. X 100. E, a macerated pendant sporangium with its membranous wail through which spores are visible. Slide No. 35154-8. X 70. F, a piece of sporangium wall associated with a few spores. Slide No. 35154-1. X 500.

Locality - Near Nidpur, Gopad river sporophyll. In one case partial fu.sion of Valley, Sidhi District, Madhya Pradesh. two sporangia in the basal region was Age - Triassic noticed. Either all sporangia were fused Remarks - So far only one specimen of with each other in their basal parts or some Bosea indica gen. et sp. novo has been were fused and the rest were free. discovered. It is a male organ built on Inside a sporangium, spores are not the pattern of a frond. It consists of an uniform in size because some are appreci• axis bearing branches right and left which ably smaller in size having minor folds on are really the sporangia bearing micro• the proximal face. These spores are ellip• sporophylls. A eletached, flatiened young tical in shape. Sometimes folds are irregular microsporophyll was lying very close to and overlapping. On distal side vertical the type specimen which showed sporangia area is present. These spores have been projecting out from its under side along marked mostly confined to the marginal the periphery. The sporangia were, there• region of a sporangium ane1 on the middle fore, pendant on the margin of the micro- part they surround the mature spores giving SRIVASTAVA - MICROSPORANGIATE FRUCTIFICATION FROM NIDPUR 21

somewhat mesh-like appearance to an under e.g., in L. indica, upper surface is non-papil• macerated sporangium. late and subsidiary cells are usually 5 in Generally a sporangium contains Weylan• number whereas in Bosea indica both the dites-type of spores described by Bharadwaj surfaces are papillate and the subsidiary and Srivastava (1969) but associated with cells are usually 6. However, these differ• these some oval spores which show branched ences are minor and could be expected transverse striations with vertical partitiofls in two distinct morphological organs of have also been isolated from the same one such as a vegetative and a sporangium. In these types, striations con• microsporophyll. There is, therefore, a verge towards both the ends and all the strong possibility of Bosea indica being the striations are united by a continuous and spore-producing male organ of Lepidopteris sub-equatorial striation. On their distal indica. face longish area is distinct. Such spores L. indica and B. indica belong to the were put under the Awnancisporites Triassic in age whereas L. Storm• by Bharaowaj and Srivastava (1969) in bergensis and L. ottonis are known to dispersed condition from Nidpur shale. occur from Middle Triassic (Africa, Australia, But their association in one sporangium Argentina) and Upper Triassic (Green Land indicates that these would have been the and Rhaetic of Scania, Sweden) respectively. variable forms of Weylandites-type of spore. Another type of male organ Antevsia is Simultaneously, it may also be speculated ascrieed to Lepidopteris by Harris (1937) that such forms must have emerged during and Townrow (1960). Antevsia is charac• the successive stages of development of the terized by having pinnately J.,ranched genus Weylandites. microsporophyll with groups of sessile pollen Comparison & Discussion - Bosea indica sacs, attached on the apex of· ultimate gen. et sp. novo is a male reproductive branches, bearing monosu1cate pollen grains. organ. The epidermal features of its In Bosea indica the microsporophyll is sporophyll closely agrees with the epidermal directly attached on the axis with pendant features of a vegetative leaf described under sporangia along the margin, having verti• Lepidopteris indica Bose & Srivastava cally and horizontally striated spores. (1972). In both, general shape and arrange• Hence, in view of these facts, it can be ment of epidermal cells, stomatal distri• safely inferred that both the male organs, bution and structure of stomatal apparatus namely, Bosea and Antevsia were borne on are quite similar to each other but there different kinds of which bore Lepi• exist minor differences between the two, doptens-type of leaf.

REFERENCES

BHARADWA], D. C. & SRIVASTAVA, SHYAM C. Sound East Greenland. Pt. 5. Meddr. Grq,n• (1969). A Triassic mioflora from India. land. 112(2): 5-114. Palaeontographica. 125: 119-149. PANT, D. D. & BAsu, N. (1973). Pteruchus indicus BOSE, M. N. & SRIVASTAVA, SHYAM C. (1972). sp. novo from the Triassic of Nidpur, India. Lepidopteris indica sp. novo from the Lower Palaeontographica. 143. Triassic of Nidpur, Madhya Pradesh, India. SRIVASTAVA,SHYAM C. (1974). Pteridospermic J. palaeont. Soc. India. 15: 64-68. remains from the Triassic of Nidpur, Madhya Idem (1973a). Nidistrobus gen. nov., a pollen• Pradesh, India. Geophytology. 4(1): 54-59 bearing fructification from the Lower Triassic SRIVASTAVA,SHYAM C. & MAHESHWARI, H. K. of Gopad river valley, Nidpur. Geoph)"ology. (1973). Satsangia, a new plant organ from the 2(2): 211-212. Triassic of Nidpur, Madhya Pradesh. Ibid. Idem (1973b). Some micro- and megastrobili 3(2): 222-227. from the Lower Triassic of Gopad River Valley, TOWNROW,J. A. (1960). The Peltaspermaceae, a Nidpur. Ibid. 3(1): 69-80. pteridosperm family of Permian and Triassic BARRIS, T. M. (1937). The fossil flora of Scoresby age. Palaeontology. 3(3): 333-361, 22 THE PALAEOBOTANIST

EXPLANATION OF PLATE

Bosea indica gen. et sp. novo Slide No. 35154-1. x 100. 5. A stoma from basal region of sporangial wall. Slide No. 35154-9. x 500. 1. Holotype No. 35154. x 1. 6-9. Spores showing variation in shape and size. 2. A.portion of fertile axis enlarged under liquid (Figs. 6, 7; proximal and distal views). Slide paraffin, to show emergence of microsporophylls No. 35154-10. x 1000; (Figs. 8, 9). Slide Nos. from longitudinally ribbed axis and pendant 35154-2 & -1 respectively. X 1000. sporangia from the lower fringe of head. No. 10. A partly broken sporangium, showing dis• 35154. x 7. tinct epidermal cells towards its basal part. 3. A broken sporangium magnified from apical Slide No. 35154-8. X 100. region to show distinct spores. Slide No. 35154-10. 11. An under macerated sporangium, showing x 500. apical dehiscence. Slide No. 35154-2. x 500. 4. Epidermal cells from the fringe region of 12. A stoma magnified from sporophyll cuticle. elongated head associated with prominent fold;. Slide No. 35154-1. X 500. THE PALAEOBOTANIST, VOL. 22 SRIVASTAVA - PLATE 1

12 1

2 8

1 1