1 Flora Malesiana ser. 11. Vol. 2 (1991) 1-132 Tectariagroup R.E. Holttum t, Kew)* Polypodiaceae subfam. Dryopteridoideae section A, auct.: C. Chr. in Verdoorn, Man. Pteridol. (1938) 543, p.p. Aspidiaceae tribe Aspidieae auct.: Ching, Sunyatsenia 5 (1940) 250, excl. Lomariopsis — of Ctenitis Gen. Fil. 153. and related genera. Aspidiaceae, group Copel., (1947) Aspidiaceae auct.: Pichi Sermolli, Webbia 31 (1977) 460—468, p.p. Dennstaedtiaceae subfam. Tectarioideae Holttum, J. Linn. Soc. Bot. 53 (1947) 152; Revis. Fl. Malaya 2 (1955) 494; Studies fern genera I, Fern Gaz. 12 (1984) 313—319; Ibid. VI, Gard. Bull. Sing. 39 (1986) 153—167. Caudex in almost all cases erect or suberect, always with a radially organized dictyo- stele; scales narrow and rather firm, marginal teeth (if present, except in Cyclopeltis) al- most always formed at the junction of two cells; i.e., the wall separating the two adjacent cells is elongated at right angles to the margin. Vascular structure of stipe consisting of small subequal vascular strands arranged in a U-formation as seen in transverse section (except in Pleocnemia where the arrangement ismore complex), the two on the adaxial side Fronds variously enlarged. amply divided with free veins, or with broader divisions in which veins anastomose variously, in a few species simple, in most (except Heterogoni- um) the basal pinnae or lobes longest with elongate basal basiscopic lobes or pinnules; costules of ultimate lamina-elements costae or ± prominent on the upper surface, branch- ing directly from the prominent upper surface of the rachis bearing them, the margins of lamina of of the decurrenton the sides the rachis. Hairs consisting several cells, not inter- grading with scales, variously present on most parts of the frond, the prominent upper surface of of in of costae lamina-segments a majority cases (at least near the base) covered with short erect hairs of several cells, the outer cell-wallsthin and collapsing on drying (in other hairs in this firm cases position may remain on drying); unicellular glands usually ± cylindric, colourless or red to yellow, variously present on surfaces of leaflets, on and stalks of in Sori indusia, on sporangia some genera. usually orbicular, covered with reniform or peltate indusia, or exindusiate, in the latter case sometimes spreading along veins. Fertile leaflets in pinnae or some species much contracted, with sporangia borne all along the veins to produce an acrostichoid appearance. Spores in most cases with a peri- foldedinto spore wings or crests, the wings variously anastomosing, the perispore in other cases spinulose or with obtuse projections. Base chromosome number 40 or 41. Distribution — with in the Old World; about 20 Pantropic greatest diversity genera. — In the 19th form Taxonomy century the of sori and conditionof venation (free or anastomosing) were by most authors regarded as the most important bases for classifica- tion. Thus the free-veined members of the present group were associated with Dryopteris and free-veined and exindusiate Thelypteridaceae, species were separated generically. This led to confusionsof various kinds. *) Dr. Holttum submitted the manuscript of his revision of the Tectaria Group for publication in Flora Malesiana not before he in long passed away September 1990. Some distributional data were added by the Editor. The illustrations are by P.J. Edwards, Kew. 1 2 Bora Malesiana ser. 11, Vol.2 (1991) The first major work in the 20th century was Christensen's subdivision of the unnatu- of under in his Index Filicum which included all ral aggregate species Dryopteris (1905) free-veined ferns withreniform indusiate sori and their obvious exindusiate relatives. For the first time he distinguished Ctenitis fromDryopteris, pointing out the relationship ofthe formerto Tectaria and also the distinctive characters of thelypteroid ferns (some of which have anastomosing veins). In his last major survey of the classification of all ferns (1938) with he retained a major family Polypodiaceae Dryopteridoideae as one subfamily; this included, in section A, Dryopteris and Tectaria with other generarelated to them, with Thelypteridaceae in section B. In 1940 Ching divided Christensen's Polypodiaceae into several families, one being Aspidiaceae, similar to Christensen's Dryopteridoideae section A of 1938. Ching divided it into two tribes, Aspidieae and Dryopterideae. In 1947 Holttum accepted Ching's two tribes, with minorchanges, but placed them as subfamilies in a major family Dennstaed- tiaceae, with the ideathatPolypodium and its immediateallies form a very different group of ferns. Copeland, writing independently in 1947, recognized a large family Aspidiaceae, and its also and the including Thelypteris allies, Athyrium/Diplazium Lomariopsis group of In his the here dealt with allies of genera. conspectus (1947: 153) genera appear as Ctenitis; to them shouldbe addedCyclopeltis which he associated withPolystichum, and Dryopolystichum excluded. Pichi Sermolli (1977) included both dryopteroid and tectar- ioid genera in his family Aspidiaceae and did not accept a division of it into two groups. Holttum (1984) discussed the above history in more detail, still retaining separate associated with and Tectaria and the groups Dryopteris objecting to Tryons' arrangement in their book of 1982 in which the two groups are confused. In 1986 Holttum presented a ofall Old World ofthe with of conspectus genera Tectaria alliance, comments on those the New World, pointing out the peculiar characters of Dryopsis Holttum & Edwards [Kew which Bull. 41 (1986) 171-204] perhaps connects the two groups. Most species of Dry- opsis are in MainlandAsia but two are Malesian. The structure of the junction of the bases of leaflets and the rachis thatbears them is here presented as the most clear distinction between the genera allied to Dryopteris and those allied to Tectaria. This is seen best in Lastreopsis, Ctenitis and Pteridrys (see fig. 311 in Holttum 1955: 524). In Lastreopsis the relationship is exactly as in Davallia; Ctenitis only differs in the margins of the lamina which are not thickened where they are decurrent on the rachis-wing. In Cyclopeltis the relationship of pinna-base to rachis is evident the of the frond. An close Davallia is also shown only near apex arrangement to by Rumohra, a genus included by several authors in Aspidiaceae. But Rumohra differs from all the here included in its dorsiventral rhizome- genera strongly structure, compar- able to that ofDavallia though not identical with it, and also in its scales. [Pichi Sermolli (1977: 465) cites Chandra's study of the vascular structure in the caudex of Maxonia as evidence of the dorsiventrality in a ally of Dryopteris ; but dorsiventrality in Maxonia is only a slight modificationof the normal dictyostele ofDryopteris, very different from that in Rumohra.] Rumohra differs from Davallia in its distribution(widely in South America, also in southern Africa its and Australasia) and in spores. In Malesia, it only occurs in New Guinea. It is link between Davallia and the perhaps a connecting Tectaria group; it needs a comprehensive new morphological study. Holttum Tectaria Group 3 Pichi Sermolli(I.e. 1977: 238) has stated that there are four different types of rachis- with the of main rachis with structure in Aspidiaceae but he deals only junctions pinna- rachises, not with the relationship between lamina-elementsand the smallerdistal rachises which I believe to be significant. I have expressed disagreement with himin 1984 (I.e.: 314). KEY TO THE GENERA teeth 1a. Teeth present at the bases of sinuses between pinna- or pinnule-lobes, the pro- jecting out of the plane of the lamina 2 b. Teethof this kind lacking 3 2a. Fronds simply pinnate with free veins; no unicellularglands on lamina or in sori Pteridrys (p. 4) b. Fronds mostly bipinnate, their veins forming at least costal areoles; cylindric glands Pleocnemia present (p. 8) least clathrate 3a. All axes of the frond bearing copious scales, the smaller ones at partly with isodiametric cells Ctenitis (p. 21) b. Smaller axes of the frond bearing few scales which are not thus clathrate 4 4a. Veins in sterile fronds anastomosing copiously; free veinlets in areoles (including those along costae) variously directed and in most species forked 5 b. Veins anastomosing to form costal areoles which lack free veinlets, or all veins free 7 5a. Fertile fronds greatly contractedand bearing indusia 6 if indusia b. Fertile fronds not greatly contracted, or so lacking Tectaria sect. Tectaria (p. 59) reniform 6a. Sterilefronds simple; fertile ones irregularly deeply lobed; indusia Tectaridium (p. 36) b. Sterile fronds pinnate; pinnae of fertilefronds linear, with continuous indusia along each side of the costae Chlamydogramme (p. 37) 7a. Some thick multicellularhairs between veins the least present on upper surface, at near sinuses between lobes 8 b. thick hairs veins surface 11 No present between on upper 8a. Basal basiscopic lobe or pinnule of basal pinnae longer than the other lobes or pinnules 9 b. Basal basiscopic lobe of basal pinnae much reduced, these pinnae widest at about mid-length Heterogonium (p. 105) 9a. Fronds not greatly longer than wide 10 b. Fronds than wide, with greatly longer many pinnae gradually increasing in size downwards Aenigmopteris (p. 102) 10a. Veins in fertile if anastomosing some species; fronds, greatly contracted, not bear- ing very small pinnules Tectaria sect. Sagenia (p. 42) b. Veins all free; fertile fronds bipinnate with very small pinnules, exindusiate Psomiocarpa (p. 100) 11a. Pinnae articulate to the rachis, entire or crenate Cyclopeltis (p. 116) b. Pinnae not articulate, deeply lobed or pinnate Lastreopsis (p. 120) Flora 1 4 Malesiana ser. n, Vol.2 (1991) PTERIDRYS Gen. Pteridrys C. Chr. & Ching, Bull. Fan Mem. Inst. Biol. 5 (1934) 129; Copel., Fil. (1947) 126; Holttum, J. Linn. Soc. Bot. 53 (1947) 153; Revis. Fl. Malaya 2 (1955) 529; Copel., Fem Fl. Philipp. (1960) 298; Pichi Sermolli, Webbia 31 (1977) 465. — Type species: Pteridrys syrmatica (Willd.) C.
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