A New Fossil Palm from Kondhali, District Nagpur: Maharashtra
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The Palaeobotanist, 27(2): 174-181, 1981. A NEW FOSSIL PALM FROM KONDHALI, DISTRICT NAGPUR: MAHARASHTRA T. S. MAHABALE Maharashtra Association for the Cultivation of Science, Pune-411 007, India & K. M. KULKARNI Department of Botany, University of Poona, Pune-411 007, India ABSTRACT A fossil palm wood, Palmoxylon kondhaliensis sp. nov., originally from Deccan Intertrappean beds and collected loose from a nalla near Kondhali Village has been described. The wood belonging to the Reniformia section of Stenzel (1904) has com• plete bark with marks of slightly elevated leaf scars and vertical cracks. mmr Cfi)rm~, ~ ~'fqq, ~~ ~ mqr ~~ ~ Q~~~l(1l- ~ !Ii'll<: ~ ~<i 'to ~lfo ~1 If'lO: ~'flil'l ~1rT m<:r e- ~!:nf Cf~ 'l'r.a-rm 'If'f ifitnft'l"f~~ e- ~fua ~'f'~q;a dl,,!'fiI66I~Ii, wIT<f~ CfiF~-m:r, 'IlT quf;, f'!;m i]"l:fT~ I R.~ (1904) ifi'tf.r.:oTtlPn ~ e- ~!JCf ~ 'IlT66f!ll1 'l<: ~ ,,~ ~ q-uf wIT ~ ,,~ n:rU e- ~Cf ';l;uT 'imf ~ ~ I INTRODUCTION are reniform, radially elongated. The bund• les have blunt auricular lobes. The median sinus is deep to shallow with 1-5 metaxylem elements lodged in the vascular part. FlY WELLmeasuringpreserved49 X 20 fossilcm waspalmcollectedstem A by one of us (T.S.M.) at Kondhali, ratio in these bundles is 1: 1 to 3 :2. Phloem a forest village 10 miles south-west of is rarely preserved (Text-figs 4-6). Radia• Nagpur. It is a complete piece of stem, ting parenchyma is present in 1-6 tiers all chocolate brownish in colour and shows around the vascular bundles (Text-fig. 3). well-preserved periderm, cortex, dermal, Its cells are cigar-shaped and measure sub-dermal and central zones. On its outer 62 X 32 fLm. The ground parenchyma is of side the distinct rings of leaf-scars and compact cells without intercellular spaces. vertical cracks are clearly visible (Pi. 1, Fibre bundles, 55-120 fLm, are circular to fig. 1). The specimen was not found in ~itu oval and irregularly distributed (Text-figs in the Iutertrappean beds, but was lYIng 2, 3). buried under the soil and debris in a nalla Cortex - It is 0·6 cm broad. Numerous nearby. Probably it was washed away out fibre bundles, 40-120 fLm, in diameter are from the original strata and redeposited crowded in the cortex. Leaf-trace bundles there. and small fibrovascular bundles (192 X 128 fLm) also occur in the cortex. They are regularly oriented. Their dorsal caps are DESCRIPTION reniform. Auricular lobes of the vascular Periderm - This is 0·6 cm broad, with bundles are round. The median sinus is somewhat sparse fibrovascular bundles, shallow and vascular part extruded. It in• measuring 250 X 96-960 X 440 fLm, 4-6 per cludes 2-5 meta xylem elements, 44-48 fLm sq cm, irregularly oriented. The dorsal caps (Text-figs 2, 7-10, 12; PI. 1, figs 4, 5). F/V 174 Pages 115, 116 'tABLE i-COMPARISON OF PALMOXYLON n. sp. WITH OTHER SPECIES OF PALMOXYLON CHARACTERS B. blanfordi P. indicum P. sagari P. khalsa P. intertrappeum P. geometricum P. sclerodermum P. arcotense P. chhindwarense P. dakshinense Palmoxylon kondlwliensis sp. nov. SCHENK (1882) SAHNt (1931) SAHN[ (1931) SAHN[ (1964) SAHNt (1931) SAHNI (1964) SAHNt (1931) RAMANUJAM (1953) PRAKASH (1958) PRAKASH (1958) No. 151jTSMjKNDL SHUKLA (1946) 2 -- 3 4 5 6 7 8 9 10 11 12 Region Central Dermal, subdermal, Subdermal Subdermal Complete basal part Central Dermal, subdermal Dermal, subdermal cen Dermal, subdermal cen- Dermal, subdermal Periderm, cortex, dermal, almost central of the tree tru nk tral tral subdermal, central Shape of the dorsal Reniform Reniform Reniform Reniforrn Cordate Cordate Cordate Reniform Reniform Reniform, cordate cap Fi bre bundles Absent Absent Absent Absent Present Absent Present Absent Absent Absent Present in cortex only Stegmata Absent Absent Absent Absent Absent Absent Present Absent Absent Present Absent Radiating parenchyma All around the fibro- Present Present around the Present arounj the Absent Absent Present only around the Absent Absent Present in dermal zone Absent vascular bundles vascular part vascular part vascular part of leaf- only trace bu ndles TabuJar parenchyma A few layers around J-2 layers 2-3 layers over the Absent Absent 1-2 layers Absent Absent 1-2 layers around the Present in dermal zone Absent the vascular bundles dorsal cap dorsal caps only Ground Tissue Lacunar, cells cylindri Not compact, slightly Cells oval, air spaces Lacunar, cells rod-like, Compact in dermal Very lacunar, cells of Compact Highly lacunar, cells nar Dermll compact, sub Compact, thin-walled L%s compact - lacunar cal, slightly stellate lacunar small sometimes branched zone, lacunar in various geometric shapes row, rectangular of dermll-lacunar, Cen round - oval cells in cells oval-cigar-shaped other zones various shapes forming tral lacunar, thin-walled dermal zone and slightly loosely fitted meshes cells lacunar in subdermal with conspiwous inter zone, cells in central cellular spaces zone of various shapes forming loose meshes Special character Metaxylem elements Usually 3-4 layers of G round tissue cells of re Radiating parenchyma Highly lacunar consisting Metaxylem elements 3-5 metaxylem elements gular geometric forms, around the vascular of narrow, more or less mostly one, rarely two in leaf trace bundles rod-shaped & Y-shaped part of leaf-trace bundle, rectangular cells of fibre bundles in dermal various shapes forming zone loose meshes Locality & Geological Near Jhansi, unknown Sagar, Eocene; Deccan Unknown Sindhi Vihira, Wardha Sind, Tertiary Seoni, M.P. Eocene South Arcot, CUddalore, Chhindwara, Eocene, Kondhali, M.S. Eo~ene. horizon traps Unknown Dis!., Eocene, Deccan Deccan Traps Tertiary, Sandstone Deccan Traps Deccan Traps Traps series, Miocene-Pliocene MAHABALE &, KULKARNI - A NEW FOSSIL pALM FROM NAGPtJR 177 ratio is 1: 1 to 1·3: 1. Ground parenchyma elements (Text-figs 11, 28-31; PI. 1, figs is not well-preserved but shows round and 10, 13). Ground parenchyma is less lacu• elongated cells. nar, made up of thin-walled cigar-shaped Dermal Zone - This zone is distinct cells, 28 X 18-120X 30 [Lm (Text-figs 31, 39). from the cortical zone and is about 1·5 cm They form at some places regular polygonal broad (Text-figs 1, 12). The fibrovascular meshes (Text-fig. 39; PI. 1, fig. 11). bundles are elliptic, 495 x 360-880 x 512 [Lm, In longitudinal section the cells are conti• closely packed, laterally compressed and guous and lie in vertical rows with small regularly oriented, their vascular part being intercellular spaces (PI. I, figs 12, 15). towards the centre. The dorsal caps are Metaxylem elements, 160-190 [Lm,have 6-7 reniform to cordate, auricular lobes round vertical rows of pits (Text-fig. 34; PI. 1, and the median sinus is deep. Yascular fig. 16). The end walls are oblique with part has a single large vessel, 108 X 128 [Lm, 4-8 transverse bars, sometimes forked (Text• rarely two. Phloem is in the form of a figs 35, 37, 38; PI. 1, fig. 18). The pro• single triangular patch (Text-figs 13-19; toxylen elements are 30-50 [Lm and have PI. 1, figs 6, 8). The frequency of vascular annular thickenings (Text-fig. 36). bundles on the outermost part of the peri• Leaf-trace Bundles - These are present phery is 190-220 per cm2• FlY ratio is throughout the cross section but are seen I: 0·75 to 3: 1. Crowding of the fibrovas• mostly in the subdermal and centra! zones. cular bundles in this part makes a sort of They are 864 X 688-960 X 650 [Lm and are continuous sheath of sclerenchyma around easily distinguished by their long and far the stem leaving only a little space for the protruding vascular part which includes ground tissue. A small amount of compact a pair of large vessels and 2-4 medium-sized ground parenchyma, composed of oval and vessels, 36-56 [Lm in diameter (Text-figs 22, thin-walled cells, 40 x 28-60 X 32 [Lm, has 23, 32, 33; PI. I, figs 14, 17). scarcely any intercellular spaces (Text-fig. 13). Subdermal Zone - It is 2·5 cm broad. AFFINITIES The fibrovascular bundles of this zone merge imperceptibly with fibrovascular bundles of The specimen belongs to the Section the subdermal zone. They lie farther apart, , Reniformia' of Stenzel (1904) as the more or less circular and irregularly oriented, fibrovascular bundles have reniform dorsal their distribution in this region being 50-70 caps. In a few bundles in the subdermal . per cm2 (Text-figs 1, 20; PI. 1, figs 2, 7). zone the caps have a slight tendency towards Dorsal caps are reniform, auricular lobes cordate form. They are, however, distinctly round and median sinus deep. They have reniform in the central region. Ground one partly excluded metaxylem element, parenchyma is less lacunar to lacunar. Its 80-160 [Lm, 2-3 protoxylem elements and dorsal pa't is somewhat lacunar. Ground single patch of phloem (Text-figs 21, 24-26; parenchyma a'-e comparable with some PI. 1, fig. 7). FlY ratio is I: 1 to 3: 2. The of the previously described Palmoxyla but ground parenchyma is less compact, com• distinct from them all in many respects (see posed of more or less thin-walled oval cells. Table 4). For example, it shows simi• The cells are irregularly ellipsoidal; those larities with Palmoxylon blanfordi Schenk near the main bundles, tangentially flattened (1882), P. indicum Sahni (1931), P. sagari measuring 40 X 29-60 X 32 [Lm(Text-fig. 21; Sahni (1931), P. intertrappeum Sahni (1931), PI. 1, fig. 9). P. geometricum Sahni (1931), P. scleroder• Central Zone - The fibrovascular bundles mum Sahni (/931), P.